Siam Physics Congress 2017

24 May 2017, 07:00 → 26 May 2017, 19:00 Asia/Bangkok

Rayong Marriott Resort & Spa

--- Physics Beyond Frontier ---

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Wednesday 24 May

Registration

Opening ceremony

Group photos

Plenary Talk I: Prof. Dr. Matthias Steinmetz

1 The Milky Way as a cosmological laboratory

The Milky Way is the galaxy we can dissolve in its indivudual constituents and thus study in most detail. The abundances of individual chemical elements in stars reflect the chemical composition of the gas at the location and time of their formation. The combined stellar record of the Galaxy can thus be used to analyze its resolved star formation history. The motions of the Galaxy’s stars can be used to study the accretion history and thus allow to identify remants of accreted and tidally disolved dwarf galaxies. The motions also allow to weigh the various components of the Milky Way and are thus of critical importance to analyze the distribution of dark matter.

The past decade has seen several major efforts to measure chemical abundances for more than a Million stars by means of large spectroscopic surveys, complemented by information of the positions, motions and distances of stars provided by ESA’s astrometry satellite Gaia, which was launched in 2013. The combined data sets thus provide us with an integrated view on the chemical and kinematical history of the Galaxy and its various stellar populations. Combined with the results of cosmological gas dynamical simulations we thus can disentangle the various physical processes that have shaped the Galaxy's structure, get a detailed view of the complex structure of the Milky Way and its convoluted formation history, and, eventually derive interesting constraints on the underlying cosmological paradigm.

Speaker: Prof. Matthias Steinmetz (Leibniz-Institut für Astrophysik Potsdam (AIP))

11:15 Coffee break

Plenary Talk II: Prof. Jürgen Rö​del

2 Physics and Politics in the Development of Lead-free Piezoceramics

While the traditional materials of choice for piezoelectric devices over the past 60 years were lead-based perovskite ceramics, the environmental- and health-concerns, supported by governmental regulations, triggered the search for new lead-free alternatives [1]. This is embedded into a view of annual usage of lead as compared to other metals and the efforts to reduce lead in various commercial products in the last decades. During the past 10 years the research output rose from 10 to 400 publications per year with China and Japan leading, Europe accounting for 10 % of the total quantity and the US only showing very select activities.

In addition, a number of companies invested large sums into research and they aim at solid financial return. Some of them produced material reproducibly in 100 kg batches and select areas were identified, where lead-free piezoceramics have an advantage to lead-containing piezoceramics. As a result, the first products started to appear at the market place.

The aim of this contributions is to review the global situation and present scientific challenges and advancements, which have been made by introducing the three main competitors based on different chemistry and different salient phase diagrams. I will highlight achievements and remaining challenges in physics and will point to fruitful fields for the near future [2].

[1] Jürgen Rödel, Wook Jo, Klaus Seifert, Eva-Maria Anton, Torsten Granzow and Dragan Damjanovic, “Perspective on the Development of Lead-Free Piezoceramics”, J. Amer. Ceram. Soc., 92 [6] 1153-1177 (2009)

[2] J. Rödel, K.G. Webber, R. Dittmer, W. Jo, M. Kimura and D. Damjanovic, „Transferring lead-free piezoceramics into application”, J. Eur. Ceram. Soc., 35, 1659-81 (2015)

Speaker: Prof. Jürgen Rödel (Institute of Materials Science, Technische Universität Darmstadt, Alarich-Weiss-Straße 2, Darmstadt, Germany, 64287)

12:30 Lunch

A1: Biological

Conveners: Prof. Jirasak Wong-ekkabut (1.Department of Physics, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand 2.Computational Biomodelling Laboratory for Agricultural Science and Technology (CBLAST), Faculty of Science, Kasetsart University, Bangkok 10900, Thailand), Dr Pongsakorn Jantaratana (Department of Physics, Faculty of Science, Kasetsart University), Thana Sutthibutpong

3 Effects of Relaxation on Drag Force and Diffusivity of Highly Charged Spherical Particles in Cylindrical Pores

Diffusion of macromolecules through nanopores of comparable sizes is affected by an interaction between the particle and the confining entities including both hydrodynamic and electrostatic interactions. The particle-pore hydrodynamic interaction causes an increase in the drag force exerted on the particle, resulting in the reduction of its diffusivity. If the particle is charged and submerged in an electrolytic solution, the particle motion creates a distortion of the electrical double layer, resulting in an excess retarding force added to the usual enhanced hydrodynamic drag. This is commonly known as the relaxation effect. In the present work, the excess force due to relaxation was evaluated from the finite element solution of the governing equations including Stokes equation, Poisson's equation and Nernst-Planck equations. The regular perturbation scheme involving the Peclet number was employed, considering the particle translocation as a perturbation on equilibrium state. The enhanced drag due to relaxation and the particle diffusivity are obtained for spherical particles confined in cylindrical pores where the particle and pore wall are of like charge and the electric potential of the system is high enough that the Poisson-Boltzmann could not be linearized. The obtained results are compared to effects of relaxation on drag force and diffusivity of macromolecules calculated by employing the perturbation involving the dimensionless surface charge density.

Speakers: Kittipitch Yooprasertchuti, Dr Panadda Dechadilok

4 Blood type screening on polymeric strip test for clinical samples

The point of care (POC) blood group typing has been developed for conveniently and immediately tests by polymeric strip test. Poly (methyl methacrylate (PMMA)) substrate was chosen and then designed the functional group layer to establish whether person is A, B, AB, or O blood type by naked eye. The substrate was modified by chemical bonding via carboxyl-methyl dextran to immobilize ABO antibody in the range of 2.5-60% v/v concentration. Clinical samples both red blood cell and EDTA blood were tested by our strip test and compared with a standard agglutination method. The result was found that there was consistent with standard method for all 80 samples. Red blood cell blood group typing is 100% precision detection and EDTA blood group typing is 97.5% precision for blood typing detection.

Speaker: Mr Chanwit Kataphiniharn

5 Unpinning of spiral waves from regtangular obstacles by stimulated wave trains

Pinning phenomena emerge in many dynamical systems. They are found to stabilize extreme conditions such as superconductivity and superfluidity. In cardiology, lengthened tachycardia correspond to propagating action potential in forms of spiral waves pinned to anatomical obstacles including veins and scares. Thus, elimination such waves is important particularly in medical treatments. We present study of unpinning of a spiral wave by a wave train initiated by multiple stimuli at a given location. The spiral wave is forced to leave the rectangular obstacle when the frequency of the wave train is higher than a threshold funpin. We found that funpin increases with the appearent length of obstacle,i.e., the projection of obstacle in the wave train direction. It implies that the orientation of the obstacle, with respect to the propagation of the wave train, plays an important role in the unpinning of the spiral wave

Speaker: Ms Benjamas Ponboonjaroenchai (Kasetsart University)

6 Improvement of electrocardiogram by empirical wavelet transform.

Electrocardiogram (ECG) is a crucial tool in the detection of cardiac arrhythmia. It is also often used in a routine physical exam, especially, for elderly people. This graphical representation of electrical activity of heart is obtained by a measurement of voltage at the skin so that the signal is always contaminated by noise from various sources. For a proper interpretation, the quality of the ECG should be improved by a noise reduction. In this article, we present a study of a noise filtration in the ECG by using an empirical wavelet transform (EWT). Unlike the traditional wavelet method, EWT is adaptive since the frequency spectrum of the ECG is taken into account in the construction of the wavelet basis. We show that the signal-to-noise ratio is increased after the noise filtration for the cases of different artifacts.

Speaker: Ms Vikanda Chanchang (Kasetsart University)

7 Pesticide Detection Based on Ion Sensitive Field Effect Transistor

Development of pesticide sensor based on the ion sensitive field effect transistor (ISFET) was investigated by using acetylcholinesterase which is an enzyme that catalyzes the hydrolysis of acetylcholine to acetate and choline. The ISFET can measure the inhibition reaction of acetylcholinesterase enzyme by the carbaryl pesticide through the pH changed in solution. The acetylcholinesterase was coated on ISFET’s surface by varying the enzyme concentration from 0.01 to 0.5 unit to select the optimum concentration for carbaryl detection. The pH effect of buffer solution was studied in the range of 6-10 to find the suitable pH for enzyme function which provides high sensitivity. The results showed that buffer solution pH 7 was the optimum pH for enzyme reaction and provided a good response for carbaryl detection in the range of 10$^{-6}$ to 10$^{-5}$ M. Moreover, the sensor stability was tested by comparison of the detection signal from ISFET that were kept at the different time.

Speaker: Mr Supanat Sasipongpana (College of Nanotechnology, King Mongkut’s Institute of Technology Ladkrabang, Bangkok, 10520 Thailand)

8 Electrical based harvesting of microalgae: Type electrodes

We investigate the harvesting of microalgae, living in a culture fluid, by an application of constant electrical current via planar electrodes are made from different materials: aluminum, stainless steel, and graphite. All of these electrodes produce similar fine sub-millimeter bubbles which can levitate the microalgae to the top surface. Unlike graphite, metal sheets are cheap and convenient to handle but both of them are prone to erosion and cause metal contamination when used as positive electrodes. To minimize the metal contamination as well as the production cost, we combine the advantage of the different materials by using metal and graphite sheets as negative and positive electrodes, respectively. A usage of the combined electrodes in a large container to harvest Dunaliella Salina microalgae for beta-carotene production is demonstrated.

Speakers: Mr Piyachat Wungmool (Kasetsart University), Mr Wu Zhe (Kasetsart University), Mr Nakorn Kumchaiseemak (Kasetsart University), Ms Sirinaree Supansomporn (Kasetsart University), Mrs Malee Sutthiopas (Kasetsart University), Mr Niran Jantawong (Kasetsart University)

A2: Phys Ed, Plasma, and Nuclear Fusion

Conveners: Prof. Pornrat Wattanakasiwich, Prof. Teerasak Veerapaspong (Kasetsart University)

9 Design Steps for Physics Stem Education Learning Activity in Secondary Education

This research aimed to provide solutions for secondary school teachers on physics who were incapable of designing decent stem education for their own learning activity contexts, and experts did not agree that it did not conform to the concept of STEM Education. It was, then, to develop steps on physics STEM Education learning system activity in secondary school education for further application.
Design steps were as follows 1. Study on research and other relevant literature reviews 2. Interview the 5 targeted instructors and experts on physics teaching and STEM Education 3. Design steps and have examination and assessment by experts for further improvement 4. Have 7 instructors design stem education learning following the steps and make teaching test on their own students.
During this moment, researcher teams were collecting data to analyze and effectively improve the design steps.
The result contributed to an emergence of 5 steps which are 1. Study on an origin, meaning, and objectives of STEM Education 2. Study and comprehend engineering design process 3. Study of STEM Education lesson features 4. Design STEM Education learning activity comprising of problematic situation prescription, objective setup, knowledge setup to allow learners to design solution methods that integrate scientific, mathematic, and technological knowledge, as well as prescription on feasible solutions based on engineering design principle and lesson plan design 5. Apply designed learning activity to teaching together with assessment and improvement.
The result of having physics teachers to design steps found that the teachers were able to design STEM Education learning activity certified by the experts that it conformed to the concept of stem education and would be more effective if they were under the guidance of engineering experts or the teachers had experience on invention or taught invention projects. Satisfaction assessment result of the teachers to design steps found that it was at “high” level . The results to the learners were that learning achievement, attitudes on physics, and critical thinking skill were significantly higher at .05 and the learners were satisfied to stem education learning activity at high level.
In addition, The results also found that the moment that the teachers did not understand and comprehend engineering design process and STEM Education objectives particularly its application objectives to Thailand was a major cause making the teachers unable to design STEM Education learning activity, One of the reasons causing problems of physics stem education teaching conduct in Thailand.

Speaker: Dr Chalognchai Teevasuthornsakul (Faculty of Science and Arts, Burapha University Chanthaburi Campus)

10 Cambodian students’ prior knowledge of projectile motion

Students always bring intuitive ideas about physics into classes, which can impact how they learn and how successful they are. To examine what Cambodian students think about projectile motion, we have developed seven open-ended questions and applied to grade 11 before (N=124) and after (N=131) conventional classes. Results revealed several consistent misconceptions, for instance, many students believed that the direction of a velocity vector of a projectile follows the trajectory at every position. They also thought the direction of an acceleration (or a force) follows the direction of motion. Two objects, which freely fall from the same height, spend different time to reach the floor because of different paths of motion. The greater angle of the launched projectile creates the greater horizontal range. The hand force imparted with the ball leads the ball goes straight to hit the target. The acceleration direction points from the higher position to lower position. These misconceptions will be used as primary resources to invent instructional instruments to promote Cambodian students’ understanding on projectile motion concepts in a following work.

Speaker: Ms So Piten (Prince of Songkla University)

11 A Worksheet to Enhance Students’ Conceptual Understanding in Vector Components

With and without physical context, we explored 59 undergraduate students’conceptual and procedural understanding of vector components using both open ended problems and multiple choice items designed based on research instruments used in physics education research. The results showed that a number of students produced errors and revealed alternative conceptions especially when asking to draw graphical form of vector components. It indicated that most of them did not develop a strong foundation of understanding in vector components and could not apply those concepts to such problems with physical context. Based on the findings, we designed a worksheet to enhance the students’ conceptual understanding in vector components. The worksheet is composed of three parts which help students to construct their own understanding of definition, graphical form, and magnitude of vector components. To validate the worksheet, focus group discussions of 3 and 10 graduate students (science in-service teachers) had been conducted. The modified worksheet was then distributed to 41 grade 9 students in a science class. The students spent approximately 50 minutes to complete the worksheet. They sketched and measured vectors and its components and compared with the trigonometry ratio to condense the concepts of vector components. After completing the worksheet, their conceptual model had been verified. 85% of them constructed the correct model of vector components.

Speaker: Umporn Wutchana (Ramkhamhaeng University)

12 A guided note taking strategy supports student learning in the large lecture classes

In higher education, lecturing has been found as the most prevalent teaching format for large classes. Generally, this format tends not to give the effective learning outcomes. Therefore, to support student learning in the large lecture classes, we developed guided notes containing quotations, blank spaces, pictures, and problems. A guided note taking strategy was selected and has been used in our introductory physics courses for many years. In this study, we investigated the results of the implementation of the guided notes taking strategy to promote student learning on electrostatics. The samples were three groups of first-year students from two universities: 163 and 224 science students and 147 engineering students. All of them were enrolled the introductory physics course in the second semester. To assess students’ understanding, we administered the pre- and post-test to the students by using the electrostatics test. The questions were selected from the conceptual survey (CSEM) and some leading physics textbooks. The result of students’ understanding was analyzed by the average normalized gains. The normalized gain of each group was 0.61, 0.55, and 0.54 respectively. Furthermore, the students’ views on learning with the guided note taking strategy were explored by interviews. Most students perceived that the strategy helped support their learning engagement in the lectures.

Speaker: Dr Jintawat Tanamatayarat (Department of Industrial Physics and Medical Instrumentation, Faculty of Applied Science, King Mongkut's University of Technology North Bangkok)

13 Assessing student understanding of measurement and uncertainty

The objectives of this study were to develop and assess student understanding of measurement and uncertainty. A test has been adapted and translated from the Laboratory Data Analysis Instrument (LDAI) test, consists 20 questions focused on three topics including measures of central tendency, experimental errors and uncertainties, and fitting regression lines. The test were evaluated its content validity by three physics experts in teaching physics laboratory. In the pilot study, Thai LDAI was administered to 93 freshmen enrolled in a fundamental physics laboratory course. The final draft of the test was administered to three groups—55 freshmen taking fundamental physics laboratory, 20 sophomores taking intermediated physics laboratory and 18 juniors taking advanced physics laboratory at Chiang Mai University. As results, we found that the freshmen had difficulties in all topics. Most sophomores and juniors had problems with experimental errors and uncertainties and fitting regression lines. These results will be used to improve teaching and learning physics laboratory for physics students in the department.

Speaker: Mr Sumit Jirungnimitsakul (Department of Physics and Materials Science, Faculty of Science, Chiang Mai University)

14 Simulation of Gamma Rays Attenuation Through Matters Using the Monte Carlo Program GEANT4

This research focuses on simulation of the radiation attenuation using a Monte Carlo program called GEANT4. In the simulation, properties and geometries of the shielding system, which are the thickness, shape and element of the shielding material, can be varied. The radiation in gamma rays regime is considered to be emitted from the isotropic radioactive sources that are Cs-137, Co-60 and I-131. The count rate of the gamma photons at specific energy is calculated to compare the ability of radiation attenuation for different shielding materials with variable thickness and shape. The study results show that the higher atomic number material can attenuate the radiation better than the material with lower atomic number. Moreover, the attenuation rate of gamma rays depends greatly on the thickness and shape of the shielding system. This is agree well to the theoretical suggestion. The results from Monte Carlo simulation using GEANT4 can be used to design the radiation shielding system for radioactive laboratories, particle accelerator institutes, radiotherapy area in hospitals, nuclear power plants, etc.

Speaker: Supasin Sukara

Physics Project Competition

TNAM2017 (NARIT)

Meeting

15:00 Coffee break

15:00 Coffee break

15:00 Coffee break

Poster Presentation I

15 Effect of Planar Electrode Shapes on Paramecium Cell Lysis Performance in Microfluidic Systems

Electrical cell lysis is an important technique in obtaining intracellular components for further analysis. In this research, three different array of shapes; comb, triangle, rectangle; of indium tin oxide (ITO) were fabricated for cell lysis in microfluidic systems. Paramecium sp. cells were used in visualizing cell disruption due to the application of 12 V$_\text{p-p}$ AC voltage between electrodes. From the observation, Paramecium cell membrane disruptions were more pronounced in triangle and rectangle electrodes. Electric field distribution inside microfluidic systems for three electrode shapes were simulated to confirm Paramecium’s transmembrane potential. Simulation results agree with the experiments that triangle and rectangle shape produce high transmembrane potential when Paramecium cells are placed between electrodes.

Speaker: Ms Chanikan Aroonnithi (Yupparaj Wittayalai School)

16 Characterization and XPS analysis of Mn-doped calcium copper titanate thin films by a sol-gel method.

Perovskite Mn-doped CaCu$_3$Ti$_4$O$_{12}$ (CCTO) thin films were prepared by a sol-gel spinning method. The films were deposited one layer at a time and each layer was annealed at 800 $^o$C for an hour. Mn doping concentration in the films was varied in the range of 0-4 wt%. As the Mn doping concentration increases, the crystallite size decreases along with decreasing in the measured FWHM of X-ray peaks. From the FESEM micrographs, the grain size decreased to 20-30 nm with the increase of Mn content to 4 wt%. The high resolution XPS spectrum of Mn 2p of 4 wt% Mn-doped CCTO film show the existence of two different Mn ions, Mn$^{3+}$ and Mn$^{4+}$. The Ca 2p regions in the XPS spectrum suggested that there are two environments for Ca atoms in the film structure. On the other hand, the XPS spectra of Ti 2p and Cu 2p regions show only the existence of Ti$^{4+}$ and Cu$^{2+}$, respectively.

Speaker: Mr Pachara Jolutsakul (Department of Physics, Faculty of Science, Chulalongkorn University 254 Phyathai Road, Patumwan, Bangkok Thailand. 10330)

17 surface water wave reconstruction using MATLAB

Measuring surface water wave properties such as amplitude and wavelength can be difficult when the wave amplitude is very small. The digital image correlation (DIC) MATLAB program makes it possible to analyze such surface wave properties. The technique relies on analyzing of pattern displacement images due to surface perturbation of random patterns at the bottom of the water container. This method can be used to recreate surface wave either in snapshot or in motion, in which the wave’s amplitude the wavelength information can be extracted from. This method can also be used in determining surface tension of other transparent liquid media.

Speakers: Mr Nirut Pussadee (Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University), Mr Sitthipong Yapo (Department of Physics and Materials Science, Faculty of Science, Chiang Mai University)

18 A facile method for Electrospinning of Chitosan/PVA /Siam weeds Nano fibers

This research studied the optimal conditions for crafting fiber of PVA / CS / SW by electrospinning techniques. The study was divided into two parts. first, This crafting fibers PVA/CS by spinning PVA/CS ratios of 50/50, 60/40, 70/30, 80/20 and 90/10 at constant feed rate 0.3 ml/h, 10 cm and 15 cm spinning distance at 7 and 8 kV voltage respectively. Part Two, This crafting fibers PVA/CS/SW by spinning PVA/CS ratios of 48:48:4, 58/39/3, 69/29/2, 77/20/3 and 88/10/2 at constant feed rate 0.3 ml/h, 10 cm and 15 cm spinning distance at 6.5-8.5 kV voltage. Then, for analyzed their microstructure by scanning microscope (SEM). The chemical structure analyzed by Fourier transform infrared spectrometer (FT-IR).
The results showed that the Optimum conditions for artificial fiber, PVA/CS can be synthetic fibers are best ratios at 50/50 feed rate of 0.3 ml/h 10 cm spinning distance at 7 kV voltage. When adding Siam weed extract edges into synthetic fibers can be best ratio at 58/39/3 (PVA/CS/SW) feed rate of 0.3 ml/h 15 cm spinning distance at 7.5 kV voltage. The smallest fiber diameter 198 ± 51 nm. And, Results from FTIR confirmed that fiber consists of polyvinyl alcohol blend with chitosan and Siam weed their combinations do not interact. Or a new substance. the nanofibers was measured and the antibacterial behavior of the nanofibers against Escherichia coli was studied by bacterial growth inhibition halos and bactericidal kinetic testing. The chitosan/PVA/Siam weeds nanofibers possessed certain antibacterial.

Speaker: Mr piriya praneekit

19 A Nonlinear Transfer Matrix Method for Third-Harmonic Generation Modeling in a One-Dimensional Metal-Dielectric Photonic Band-Gap Structure

In this work, a nonlinear transfer matrix method, which is simple, fast, and, accurate numerical method for nonlinear optical phenomenon modeling, has been used to develop a theoretical model of a third-harmonic generation with nondepleted pump in one-dimensional metal-dielectric photonic band-gap structures for oblique incidence. The advantage of this formalism is considering multi-reflections and interferences between all forward and backward direction components of fundamental and third-harmonic waves. The fundamental and third-harmonic field intensities, which distribute along the sample structures, have been calculated for both TE and TM modes. And conversion efficiencies have been also calculated as a function of the thicknesses of metal and dielectric layers, and incident angles of fundamental wave. With optimal incident angle and layer thicknesses, the greatest conversion efficiency of third-harmonic generation can be achieved. In addition, the plasmonic enhancement of third-harmonic generation, which is occurred because of field localization between metal-dielectric interfeces, has been examined with the proposed formalism.

Speaker: Surawut Wicharn

20 A novel spectrometer based on the near-field Talbot effect

By making use of advanced technique of the near-field Talbot effect, we design a novel spectrometer. Our method provides a compact and portable spectrometer according to the characteristic of the Talbot effect. Here, we propose the idea with the simulations done with reasonable values. With vibration and temperature adjustments, the high resolution over a range of a few nanometers can be obtained.

Speaker: Mr Withun Sutham (Department of Physics, Faculty of Science, Burapha University, ChonBuri Province, 20131, Thailand)

21 A Study of Ferrofluid Shape Formation under Influence of Magnetic Field from Various Permanent Magnet Shapes

When ferrofluid is in a presence of external magnetic field, different peak patterns are formed depending upon shape and magnetic field strength of permanent magnets. In this study, 2 dimensional magnetic field distribution from different magnet shapes were mapped and compared with the simulated magnetic field distribution in order to use magnetic field strength at particular location to calculate magnetic force exerting on ferrofluid. Balance between ferrofluid surface tension and magnetic force on ferrofluid leads to a good approximation of peak pattern distribution of ferrofluid.

Speakers: Mr Tananut Sanghong (Chiang Mai University Demonstration School), Mr Tanabodee Kaewwichian (Chiang Mai University Demonstration School)

22 Adsorption study of gas molecules on ZnO decorated carbon nanotubes

Carbon nanotubes (CNTs) and zinc oxide (ZnO) are one of the most popular materials for gas sensing applications due to its their high electron transfer rate, large specific surface area, promising electronic and structure properties. However, gas sensor based on ZnO nanocluster decorated CNTs is still limited. In this work, we have simulated the models the formation of ZnO nanocluster decorated CNTs and investigated the theoretical study of adsorption of gas molecules (such as methanol, ethanol and isopropanol ) on ZnO nanocluster decorated CNTs gas sensor for the first time by using self-consistent charge density functional tight-binding (SCC-DFTB) method. To find the most favorable adsorption configuration, gas molecules were placed at various distances (d) above ZnO surface decorated CNTs. Its interaction energy (𝜟E) is calculated by the following equation:
𝜟E=E(gas molecules+ZnO-CNTs)-E(ZnO-CNTs)-E(gas molecules), where E(gas molecules+ZnO-CNTs), E(ZnO-CNTs)and E(gas molecules) are the total energies of gas molecules+ZnO-CNTs, ZnO-CNTs and gas molecules systems, respectively. The highest interaction of methanol-ZnO decorated CNTs is found to be -13.28 eV at the distance of 2.60 Å while those of isopropanol-ZnO decorated CNTs and ethanol-ZnO decorated CNTs are -12.75 eV and -12.72 eV at the distance of ~2.40 Å and ~2.60 Å, respectively. It can suggest that the ZnO decorated CNTs sensor owns high selectivity to methanol comparising with isopropanol and ethanol. The electronic structures of the ZnO nanocluster decorated CNTs gas sensor before and after gas adsorption will be discussed in more details. The sensing mechanism related to methanol detection will be highlighted.

Keyword: CNTs sensor, ZnO sensor, SCC-DFTB method, ZnO decorated CNT, Gas Sensor, Methanol Sensor

Speaker: Mr Yotsarayuth Seekaew (Department of Physics, Faculty of Science, Kasetsart University, Chatuchak, Bangkok 10900, Thailand)

23 Application of atmospheric-pressure argon plasma jet for bread mold decontamination

Atmospheric-pressure plasma (APAP) is a promising non-thermal technology for microbial control and prevention minimally affecting quality of foods. Effect of APAP jet on the growth of bread molds, including Aspergillus sp., Rhizopus sp., and Penicillium sp., isolated from white bread were investigated. The molds were isolated, verified, cultured to fully grown on potato dextrose agar (PDA), and subsequently treated with APAP jet using plasma generating power at 24 W for 5, 10, and 20 min, respectively. The inhibition of mold growth was investigated by comparing fungal dry weights and the effect on fungal cell structure was observed using compound light microscope. The results indicated that the 20-min treatment time is most effective in retarding the growth of the three bread molds. However, this level of generating power did not lead to destruction of the cellular structures for all the three fungi. Plasma generating power and treatment time are significant parameters determining the success of bread mold decontamination and further investigation on real bread matrix is needed.

Speaker: Dr Panakamon Thonglor

24 Application of Silver Nanoparticles for Natural Rubber Latex

Antibacterial activity of silver nanoparticles (AgNPs) has been attracted many interests in several applications such as food packaging, medical devices, wastewater treatment and textile fabrics. In this work, antifungal activity of AgNPs for natural rubber latex has been investigated. A technique of green AgNPs synthesis route has been presented based on aqueous silver nitrate (AgNO$_3$) and Pistiastratiotes L. extracts acted as reducing agent. The antifungal activities of the AgNPs against Fusarium oxysporum, Geotrichum sp., Aspergillus oryzae, Rhizopus oligosporus, Penicillum sp. and Trichoderma sp. (fungi in natural rubber latex) were analyzed by disc diffusion method. The synthesized AgNPs were characterized by a UV/Visible spectroscopy (UV-Vis) and Transmission Electron Microscopy (TEM). The results exhibited the surface plasmon resonance at 395 nm. The average diameter of synthesized AgNPs was about 14-20 nm and spherical in shape. The synthesized AgNPs exhibited activity against fungi.

Speaker: Ms Pranlekha Traiwatcharanon (Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand)

25 Application of tapered glass capillary microbeam in MeV-PIXE mapping of longan leaf for elemental concentration distribution analysis

The aim of this study was to understand elemental concentration distribution in local longan leaves for revealing whether and how the plant was affected by the environment or agricultural operation since longan trees were normally heavily sprayed with fertilizer and pesticide and chemical residues might be long lasted on the leaves. The analysis was carried out using the MeV-microbeam particle induced X-ray emission (PIXE) mapping technique which was achieved by a home-developed tapered glass capillary microbeam system based on the 1.7-MV tandem accelerator and its ion beam analysis beam line at Chiang Mai University. The microbeam was coming from the capillary with a 100-µm-diameter exit and the ion beam was of 2-MeV proton. This study was interested in difference in the elemental concentration and distribution between the leaf midrib and lamina areas. In the measurement, the micro proton beam after the tapered glass capillary analyzed the leaf sample at a fixed spot of about 150 µm in diameter for 1000 seconds, while the leaf held on the sample stage was translated step by step over a 1,350-µm range across the leaf midrib edge to the leaf lamina area, resulting in total 9 data requisition spots to realize a scanning of the interesting area. The resulting data were colored to form a map of the elemental concentration distribution. Analysis from the map revealed 7 dominant elements, which were Al, S, Cl, K, Ca, Sc and Fe. It was interestingly found that in the midrib region, Al, S, Cl, K, Ca, Sc were relatively higher in concentration than in the lamina area, while the Fe concentration was in an opposite trend to that of the others. The only indication of fertilizer and pesticide elements detected in the leaf sample was of K.

Speakers: Liangdeng Yu (Thailand Center of Excellence in Physics), Dr Nirut Pussadee (Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thiland ), Mr Sirawut Natyanun (Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai, 50200, Thailand)

26 Biocompatibility of TiO2, TiN and TiNO Thin Films Deposited by DC Reactive Magnetron Sputtering

Titanium dioxide (TiO2), Titanium nitride (TiN) and Titanium oxynitride (TiNO) are considered as promising material for the medical biology applications. In this study, The properties of biocompatibility on TiO2, TiN and TiNO thin film deposited by dc reactive magnetron sputtering on glass substrate were investigated. The material characterized techniques such as x-ray diffraction (XRD), atomic-force microscopy (AFM), contact angle measurement were used to analyze crystal structure, surface morphology and wettability, respectively. The standard toxicity test method (Assay based on cell cultures) was employed on the various films and observed the number of cell on the film surface by scanning electron microscopy (SEM). It’s was found from the XRD spectra that TiO2 thin film shows the amorphous structure, whereas the TiN and TiNO thin films exhibit the polycrystalline structure. The surface roughness (Ra) of the films obtained by AFM is in the range of 1.77 - 4.17 nm that Ra increase from TiNO, TiO2 to TiN thin film. The contact angle of the films is between 20.37 - 61.60° and decreases from TiO2, TiNO to TiN. The various films are non-toxicity on the tissue cells. But TiNO spread cell is mainly shows on TiNO indicating the ratio of reactive gas affects the biological response of cells.

Speaker: Ms jita vachabuskorn

27 Characteristic of sputtered Co75Ag25 film on various under-layer and polyimide substrate

The Co75Ag25 films were deposited on Co, Ni, Cr and Al under-layers and polyimide substrate by RF-sputtering. All of films exhibited soft perpendicular anisotropy with HCP-Co (201), (220) and FCC-Ag (111), (200) structures. The Co75Ag25 film on Co under-layer showed regular grain distribution and maximum grain size of about 32.2 nm whereas the film on Ni under-layer showed minimum grain size and surface roughness of about 9.8 and 1.3 nm, respectively. The film deposited on Cr under-layer showed maximum perpendicular coercivity and highest squareness ratio about 181 G and 0.112, respectively while the film on Co under-layer showed maximum saturation and remanent magnetization in both of parallel and perpendicular measurement. All results implied that magnetic properties and surface roughness and morphology of sputtered Co75Ag25 film are dependent on under-layer material.

Speaker: Nittaya Sanganan

28 Characterization of Ag doped WO3 synthesized by electrospinning

SEM technique was assisted to selected the best condition of 5 wt% Ag doped WO3 nanofiber which synthesized by electrospinning method and calcined at 550 ๐C for 2 hours then were investigated the characteristic via X-ray diffraction, Raman spectroscopy, photoluminescence, UV-visible, FTIR and TEM technique. The results show that is product of orthorhombic Ag-WO3 nanofiber with 60 nm diameter and 2.53 eV photon energy gap semiconductor.

Speaker: Mr Jananan Kamsri (Author)

29 Charge Mobility of Organic Solar Cells using Low Cost Pulsed Laser for photo-CELIV

Charges mobility is the key factor to determine the performance of bulk heterojunction organic solar cells. Many relevance approaches have been utilized to investigated the charges mobility. Charge extraction by linearly increasing voltage (CELIV) is one of the famous technique. However, the excitation light source is limited to the commercial short pulse laser or LED which is rather high cost. Herein, the simple <100 ns pulse generator circuit to drive the cheap laser diode have been developed and used as the light source in photo-CELIV. The set-up has been performed with the standard bulk heterojunction organic solar cells. Then the charges mobility of such device is carried out and compared with the literature.

Speaker: Mr Sorawit Changsalak

30 Charge Mobility of Organic Solar Cells using Low Cost Pulsed Laser for photo-CELIV

Charge Mobility of Organic Solar Cells using Low Cost Pulsed Laser for photo-CELIV

Sorawit Changsalak1, Wachirawit Srisa-nga1, and Yingyot Infahsaeng1*
1Division of Physics, Faculty of Science and Technology, Thammasat University, Klong Nueng, Klong Luang, Pathum-Thani, Thailand

*E-mail: yingyot.infahsaeng@gmail.com

Abstract
Charges mobility is the key factor to determine the performance of bulk heterojunction organic solar cells. Many relevance approaches have been utilized to investigated the charges mobility. Charge extraction by linearly increasing voltage (CELIV) is one of the famous technique. However, the excitation light source is limited to the commercial short pulse laser or LED which is rather high cost. Herein, the simple <100 ns pulse generator circuit to drive the cheap laser diode have been developed and used as the light source in photo-CELIV. The set-up has been performed with the standard bulk heterojunction organic solar cells. Then the charges mobility of such device is carried out and compared with the literature.

Keywords: photo-CELIV, charge mobility, organic solar cells, short pulse circuit

Speaker: Mr Sorawit Changsalak

31 Cholesterol Effect on Physical Properties of Niosome Bilayers: A Molecular Dynamics Study

Molecular dynamics simulations were employed to investigate the cholesterol concentration effect on the physical properties of niosome bilayers such as area per molecule, membrane thickness, hydration structure, fluidity and diffusion coefficient. All simulations were carried out at a constant temperature of 300 K by using Gromacs package 5.1.2. We found that increase in cholesterol numbers to form niosome bilayers results increase in area per molecule and compressibility, but decrease in the membrane thickness. These results suggest that the cholesterol concentrations cause significant change in the phase formation of niosome bilayers.

Keywords: Niosome Bilayer, Molecular Dynamics, Cholesterol Concentration, Membrane Thickness, Diffusion

Speaker: Mr Likit Temprom

32 Classical Nuclear Simulations of the $\pi^{+}({^3}He,ppn)\pi^{+}$ Reactions with Quantum Corrections

We investigated quantum corrections to classical nuclear simulations of the $\pi^{+}({^3}He,ppn)\pi^{+}$ reactions.These simulations are often used to describe nuclear reactions which lead to many final states.The ratio of the quantum multiple scattering to the classical cross section for the same process is used as a correction to the classical model calculation.The single,double,triple and all scatterings for the scattering protons of different angles are presented.

Speaker: Dr Rachen Ratanarojanakul

33 Conceptual Study of Possibility for Droplets to Achieve Superheated in Edge Tokamak Plasmas

Molten droplets are probably generated in a fusion tokamak through splashing of molten layers of plasma-facing surfaces, during transient events such as disruptions and edge localized modes (ELMs) at which surface melting is unavoidable, and melting of solid wall-material debris, i.e. dust/flakes, by heat flux of an energetic fusion plasma. Molten droplets are allowed if plasma-facing materials are made of metals except carbon (C). As ITER is now planning to use tungsten (W) for its divertor and beryllium (Be) for its main wall, dust and droplets should mostly consist of both wall materials. As mentioned that a fusion plasma is so energetic, it is possible to have droplets staying in the plasma long enough before a fusion operation terminates. The assumption is strengthen by the existences of many spherical dust, caused by surface tension of liquid phase. This suggests that to study metallic dust transport, some phenomena occurring especially in liquid phase should be focused on. By adapting the derivation of floating potential determination, such as Orbital Motion Limited (OML) theory, we are permitted to determine ion and electron momentum fluxes. This results in actual pressures on dust and droplet in a plasma. Moreover, net pressure on a droplet does matter because it determines boiling temperature of the droplet materials. This should influence on behaviors of dust/droplet transport in tokamaks. We conduct this preliminary study to consider whether or not superheating by depressurization can be achieved on a droplet in a fusion plasma. We believe superheating should occur if a droplet encounters steep number density and temperature profiles in tokamaks, i.e. edge transport barrier in H-mode. If such steep plasma profiles allow droplet superheating, this should suggest further effects, for example localized impurity deposition by electrostatically-enhanced vapor explosion, superheating rocket force for abnormal high speed droplet etc., which should be never found for non-liquid C dust.

Keywords: misty plasma, plasma-surface interactions, dust, tokamak, Orbital Motion Limited (OML), Edge Localized Modes (ELMs), disruption, superheating.

Speakers: Dr Nopparit Somboonkittichai (Department of Physics, Faculty of Science, Kasetsart University), Dr Michael Coppins (Blackett Laboratory, Imperial College London, South Kensington, London SW7 2AZ, United Kingdom)

34 Construction of 3D Image of Surface Coated with Micro-Scale Transparent Layer by Analyzing Speckle Interferogram with Fast Fourier Transform

Light interferometry is one of great non-destructive tools for making a surface profile image of materials. Because of phase difference analyzing method as a Fast Fourier transform (FFT), 3D surface profile image can be constructed from a speckle interferogram of He-Ne laser.[ref] However, 3D image of a surface coated with micro-scale transparent layer cannot be structure by using He-Ne laser as a light source of Michelson Interferometer (MI). In this research, 3D image of groove surface of standard gauge block, coated with transparent layer, is constructed by using FFT for analyzing the speckle image taking form MI with a low coherence light source as Superluminesent diode (SLD). The constructed surface image of the coated surface well agrees with the one of uncoated surface built from the same method. It also agrees with the one of uncoated surface analyzing the interferogram of He-Ne laser as a light source of MI by using FFT, as well.

Speaker: Mr Parinya Duangklang (Chulalongkron University)

35 Control the Crystal Growth of Al-doped ZnO Thin Film Prepared by Pulsed Laser Deposition and The Influences on Its Optical and Electrical Properties

Transparent conducting thin film is an important layer determining the efficiency of optoelectronic devices. Materials shown the wide-range transparency together with high conductivity are of interest. Among materials providing such optical and electrical properties, metal-doped ZnO is a promising material that gain tremendous attractions. In this work, highly transparent and highly conductive thin films of Al-doped ZnO (AZO) are achieved by pulsed laser deposition (PLD). By changing the substrate temperature in the range of room temperature to 500 $^\text{o}$C during the deposition process, the preferential growth direction of AZO crystal is controlled and, as a consequence, the surface morphology, optical and electrical properties of AZO thin film are able to be manipulated. X-ray diffractrograms as a function of substrate temperature clearly illustrate the ability to control the preferential growth direction of AZO. At the low substrate temperature, the growth along [002] direction corresponding to c-axis of hexagonal ZnO is only observed. By elevating substrate temperature, not only crystallinity of AZO thin film is further improved but also the competition of crystal growth along the [002], [001] and [101] directions are occurred due to the increase of total energy and surface mobility of adatom. The AZO films obtained by all preparation conditions exhibit an n-type semiconducting characteristics, furthermore, the carrier concentration and the carrier mobility of AZO thin films can be optimized to reach 4.10×10$^\text{20}$ cm$^\text{-3}$ and 7.53 cm$^\text{2}$/Vs, respectively. The excellences in both carrier concentration and mobility of AZO thin film lead to very low resistivity of 2.08×10$^\text{-3}$ $\Omega$ cm. In addition, the wide optical band gap of ~3.50 eV together with the high transparency over 85% is obtained from the AZO thin films. The exceptional optical and electrical properties of AZO thin film demonstrate that such material has enough potential to become a promising candidate using in optoelectronic applications.

Speaker: Mr Narathon Khemasiri (College of Nanotechnology, King Mongkut’s Institute of Technology Ladkrabang, Chalongkrung Rd., Ladkrabang)

36 Dead and living yeast cells analyzer using electrical force induction

The present project had been a collaborative project fully supported from Singha Beverage Company to invent the novel equipment that could both determine dead and living cells with the rapid real-time analysis for on-site operation and most importantly offer the prospect of effective separation of dead vs. live cells. We employed the principle of cell polarizations in AC non-uniform electric fields with the exact theoretical calculation of the lower critical frequency (LCF) analyzed using the RC model for a spheroid to separate dead and living yeast cells. The successful identification and separation of live vs. dead cells was achieved by a combination of a sequential signal generator (SSG) (to be patented) equipped with a tablet touch screen computer interface for prompt commands. Dead and living yeast cells were completely separated by tuning electric field frequencies at the unique value (concealed). Percentages of both dead and living cells were analyzed throughout the image processing protocol.

Speaker: Prof. Sakshin Bunthawin (Biotechnology of Electromechanics Research Unit, Science of Physics, Faculty of Technology and Environment, Prince of Songkla University, Phuket 83120, Thailand)

37 Dependence of contact angle on deposition time for superhydrophobic carbon nanoparticles films

We investigated superhydrophobic carbon nanoparticles (CNP) films coating on glass slides. The films were deposited by candle soot layers from combustion flames. Contact angle for water droplets increase dramatically from 44.8±4.7˚ for clean glass slides to 157.6±6.6˚ when the glass slides coated by CNP films for 10 seconds. The contact angle of water droplets on CNP samples decreases with films deposition time. It tends to approach the constant angle of ~150˚ after coating for 300 seconds. To examine the coating CNP films on non-flat surfaces, two types of samples, carbon nanotubes (CNT) and graphite flakes (GF) covered glass slides, were prepared for coating with CNP films. Contact angles of CNT and GF coated samples are 80.1±12.6˚ and 134.7±4.8˚, respectively. After coating CNP films for 10 seconds, they increase to 135.7±7.4˚ and 135.8±12.8˚. Also, longer deposition time causes the decrease of contact angle with deposition time, resembling to the CNP film samples. Particle size and film thickness of CNP films were measured by scanning electron microscopy. We suggested that increasing multiple scale roughness of CNP films could lead to larger contact area between droplets and CNP films, resulting in decrease of contact angles.

Speaker: Dr Sumet Sakulsermsuk (Chiang Mai Univerisity)

38 Design and performance of a laser-based weed control system

Design and performance of a laser-based weed control system
Sirinun Sirikunkiti and Amarin Ratanavis
Department of Industrial Physics and Medical Instrumentation, Faculty of Applied Science, Lasers and Optics Research Center (LANDOS), Science and Technology Research Institute, King Mongkut’s University of Technology North Bangkok, Thailand

This paper investigates the influence of CO2 laser as a non-contact tool for weed control application. The study aims specifically to the unfocused beam treatment for distant targets. The optical design was evaluated by an optical design software. The spatial profile of the laser beam was analyzed. The characteristics of the laser beams at targeted distance were explored. Based on the optical setup, the optimal expanding of the laser beam was archived. The relation between irradiation times and spot sizes was examined. These results demonstrate the potential of CO2 laser as promising alternative for an efficient weed control.

Keywords: Lasers, Weed control, Physical optics propagation

Speaker: Mr Sirinun Sirikunkitti

39 DEVELOPING CONCEPT ON ENERGY CONSERVATION USING SIMPLE EXPERIMENTS FOR GRADE 10 STUDENTS

The purpose of this research was to develop concept and retention rate on energy conservation. The activities included simple and easy experiments. This experiments looks at energy transformation from potential to kinetic energy. The samples were 30 students which were purposively selected from grade 10 in the second semester of the 2016 academic year. The research tools consisted of learning lesson plans, learning achievement test. The results showed that the experiment set worked perfectly and can be used for learning activities. The students’ achievement score was significantly increased at statistical level of .05 and the students’ retention rate was in a high level and learning behavior was in the good level. This simple experiments was an opportunity for students to learn to demonstrate to their future friends and experience encouraged the students to use their familiar models to explain phenomena in the daily life.

Speakers: Mr Sakchai Rachniyom (Faculty of Science, Ubonratchathani University), Dr Sura Wuttiprom (Faculty of Science, Ubonratchathani University)

40 Developing dye sensitizied solar cells with natural dyes and polymer electrolytes

We have fabricated dye sensitized solar cells and improved the efficiency of the cells by doping aluminum (Al) in anodization process during synthesizing TiO2 nanotubes (Titania nanotubes). We have studied the microstructure of titania by X-ray diffraction (XRD), scanning electron microscopy (SEM) and Atomic Force Microscopy (AFM), optical property by UV-visible spectroscopy, and the effect of Al-doping on the efficiency of the solar cells. We also present the polymer electrolytes on the efficiency of the cells by comparing 2 polymers: the polyacrylonitrile-co-styrene and polyethylene oxide.

keyword: dye sensitized solar cells; polymer electrolytes;Titania nanotubes

Speaker: Wachira Seesad (Department of Physics, Faculty of Science, Ubon Ratchathani University)

41 Developing students’ learning achievement and experimental skills on buoyancy and the involvement of Newton’s third law through experimental set

The purposes of this research were: to construct packages of operations on buoyancy and the involvement of Newton’s third law, to enhance achievement score of students on buoyancy and the involvement of Newton’s third law , to enhance experimental skills on buoyancy and the involvement of Newton’s third law and to evaluate students’ attitude towards the packages of operations on buoyancy and the involvement of Newton’s third law using inquiry method. The samples were 42 Mattayomasuksa V students in academic year 2016 at Hatyaiwittayalai School, Hatyai, Songkla. The research method was one group pretest-posttest design. The research tools consisted of experimental set on buoyancy and the involvement of Newton’s third law, the learning achievement test on buoyancy and the involvement of Newton’s third law and the students’ attitude questionnaires. The experimental skills of most students was in a good level . The satisfaction of most students was in a good level. The research showed the learning achievement after instruction higher than that before instruction using experimental set at the significant level of .05 and the class average normalized gain is in the medium gain

Speakers: Mr Chokchai Jaewijarn (Ubonratchathani University), Dr Sura Wuttiprom (Ubonratchathani University)

42 Development of Dielectric Barrier Discharge for Reducing Microbial Contamination in Pepper (Piper nigrum) and Sesame (Sesamum indicum Linn.) Powder

This research is designed to determine the efficacy of DBD plasma to reduce the microbial contamination of pepper and sesame powder. The AC high voltage power supply was used with voltage up to ±20 kV and the frequency of 5.5 kHz is applied to DBD. The gap of DBD electrodes was set at 5 mm. In raw initial samples, The total aerobic count of pepper (Piper nigrum) was found at quite high level of 5.40 x105 CFU/g. Coliform bacteria were also found both in sesame (Sesamum indicum Linn.) powder and pepper. Both kinds of samples were treated with plasma for 2, 4, 6 and 10 minutes. Results indicated that plasma treatment at 2-10 minutes reduced the total aerobic count of pepper allowed to achieve the acceptable microbial level for spices. The plasma treatment times in this experiment were effective in reduced coliform bacteria both in pepper and sesame powder (MPN/g <3). Plasma from dielectric barrier charge can reduce Staphylococcus epidermidis in sesame which was artificially contaminated with 3.50 x 102 CFU/g resulting in 0.15-0.5 log cycle reduction of microbial load.

Speaker: Jiraporn Promping

43 Development of Neutron Imaging System for Neutron Tomography at Thai Research Reactor TRR-1/M1

The neutron imaging is a powerful non-destructive technique to investigate the internal structure and provides the information which is different from the conventional X-ray/Gamma radiography. By reconstruction of the obtained 2-dimentional images from the taken different angle around the specimen, the tomographic image can be obtained and it can provide the information in more detail. The neutron imaging system at Thai Research Reactor TRR-1/M1 of Thailand Institute of Nuclear Technology (Public Organization) has been developed to conduct the neutron tomography since 2014. The primary goal of this work is to serve the investigation of archeological samples, however, this technique can also be applied to various fields, such as investigation of industrial specimen and others. The conventional technology of neutron image recorder has been replaced by a digital camera coupled with a fluorescence screen to get a higher performance and provide more convenience. The shielding wall of neutron imaging room has been renovated and a neutron shutter has been renewed for physical and radiation safety purposes. Moreover, the new rotation stage has been designed to support the specimen turning for this system.
This research paper presents the performance study of a high-efficiency and high-resolution neutron camera manufactured by Neutron Optics and shows the obtained tomographic images. Furthermore, the updated status of the neutron imaging room renovation is described.

Speaker: Dr Sarinrat Wonglee (Thailand Institute of Nuclear Technology (Public Organization))

44 Development of the teaching sound frequency with Sing Sharp mobile phone and pipe pressure for KARAOKE subject

In practice pronunciation, volume and frequency in the course of karaoke. Student in classroom training in class hour cannot be trained to look for suitable projects. The project looks to fit the mouth to get the frequency and volume of demand at home because there is no volume and frequency of the sound to the uninitiated.
Sing sharp leach program is able to tell the minister that the volume and frequency of the vocal was able to study the structure of the mouth, voice characteristics required.
In this research, teaching various aspects of oral utterance garage. The volume and different frequencies. The working class has to be able to learn at home.
In the test, the student has to study the various aspects mouth to mouth, frequency and volume, "OU" voiced.
To maintain the level of articulation The results of training Found that 122 people have voiced the threshold to 90 percent

Speaker: Mr thienchai ounsumran

45 Development of X-ray fluorescence technique for tin oxide analysis

The purpose of this work was to develop technical analysis of X-ray fluorescence (XRF) and compare with technical neutron activation analysis (NAA). In this study, three samples of tin oxide (SnO) were used to be the reference materials. The results from NAA show the content of tin were 79.39, 77.48 and 73.35 wt%. While the XRF analysis in unnormalized mode show the content of tin were 68.77, 67.42 and 61.60 wt% and normalized mode were 72.44, 77.95 and 68.71wt%, respectively. The SnO were mixed with borax that use as a binder. The borax contents were varied from 30 to 70 wt%. The XRF in normalized mode result show the sample that mixed with borax 70 wt% has the highest accuracy of tin were 75.71, 74.61 and 71.01wt%. Our study demonstrated that improved using XRF technique in normalized mode and mixed with borax 70wt% to analyses the content of tin use instead NAA technique. From the experiment could be apply to determine the concentration of tin in various industry.

Speaker: Chalongwut Boonpratum (Department of Physics, Faculty of Science, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand)

46 Diamond-like carbon films prepared by RF magnetron sputtering

Diamond-like carbon thin films were prepared by RF magnetron sputtering. Different deposition conditions were experimented. The main variable parameters were the argon flow rate, RF power and bias voltage. The carbon films were characterized by photoemission spectroscopy and soft X-ray absorption spectroscopy. In this report, the results from the measurements will be reported and discussed.

Speakers: Ms Jidapa lomon (Suranaree University of Technology), Ms Ponthip Chaiyabin (Suranaree University of Technology)

47 DIY Low Cost Thick Lenses kit Applied Teaching of Parallel light rays passing through lenses in either direction in Physics

The Thick lenses was developed and fabricated by DIY (Do it yourself) Low Cost process that applied teaching the focal length for parallel light rays passing through lenses in either direction in Physics, to increase good achievement and attitude of students. This instrument kit was made form transparent acrylic Perspex thickness of 2 mm. It was cut rectangle form an area the size 2x15 cm2 and bent by heat air blower. Next, two plastic bend which have two spherical surfaces with radii of curvature R1 and R2 of about 3-4.5 cm were composed to be the thick lenses form base on acrylic platform. Next, liquids such as Ice (H2O), water, oil, glycerin and gasoline that have the liquids index of refraction (n) 1.31, 1.33, 1.40, 1.47 and 1.50, respectively, were poured into thin lenses form of acrylic form. The 36 students in grade 10 at Mengraimaharaj Witthayakhom School, Chiang Rai, Thailand, were tested by this instrument. The 5Eenter code heres model of teaching and the one group pretest-posttest design were used to study of education through learning activities. To determine the effectiveness of instrument and learning achievement of students were evaluated by the satisfaction analysis. While the attitude of the students was interpreted by the observation and recording of results from other activities. In this research, it was found that the instrument kit using of 5Es model with this instrument has very useful. The students can be easy understood about the light rays passing through lenses in either direction. The results have shown that the 83.33 percent of students were satisfied to learn. Meanwhile, the enhancing of learning achievement in grade 10 students are 80.92/78.61 percent and the sample was found that the attitude of students increase.

Speaker: Dr Meechai Thepnurat (Chiang Rai Rajabhat University)

48 Effecst of Dielectric Barrier Discharge Plasmas Treatment on Egg Shell

Dielectric Barriers Discharge (DBD) plasmas is a cold plasma that can be generated in atmospheric pressure, thus allows it to be used on various applications. In this work, DBD plasmas will be used for treating egg shell. The results in terms of surface modification will be presented.

Speaker: Dr Nopporn Poolyarat (Physics department,Faculty of Science and Technology, Thammasat University)

49 Effect of annealing conditions on polycrystalline silicon produced by the inverted aluminum induced crystallization of amorphous silicon films on glass substrates.

The effect of various annealing treatments on the structure properties of crystalline silicon (c-Si) produced by the inverted aluminum induced crystallization of amorphous silicon (a-Si) films was studied. The surface morphology and grain size of c-Si films were observed by optical microscope, SEM and AFM. X-ray diffraction and Raman spectroscopy were used to study quantity of Si crystallization due to thermal annealing. Results showed that the c-Si with average grain size of 27 nm in a (111) orientation were obtained by the thermal annealing at 300 oC for 1 h. Prolonged heat treatment improved Si crystallite quality and increased the average grain size.

Speaker: Ms Kanyarat Kesrisom (Department of Physics, Faculty of Science, Kasetsart University, Bangkok, Thailand, 10900)

Abs ID299_spc2017.pdf

50 Effect of Copper Oxide Nanoparticles as a barrier for Efficiency Improvement in ZnO Dye-Sensitized Solar Cells

CuO nanoparticles (CuO NPs) were used as a barrier layer in ZnO dye-sensitized solar cells (DSSCs) to obtain high power conversion efficiency. The barrier layer was investigated in terms of the size of CuO NPs by varying power of pulsed Nd:YAG (1064 nm) laser ablation. Morphological and optical properties of CuO NPs were characterized by transmission electron microscopy (TEM), UV-visible spectrophotometry (UV-vis) and dynamic light scattering (DLS). It was found that the CuO NPs are rather spherical in shape with diameter in between 20 - 132 nm. In addition, the energy gap of CuO decreases with the increase of CuO NPs size. The power conversion efficiency of ZnO DSSCs was measured under illumination of simulated sunlight obtained from a solar simulator with the radiant power of 100 mW/cm$^2$. The results showed that the ZnO DSSC with the CuO NPs with size of 37 nm exhibits the optimum power conversion efficiency of 1.01% which is higher than that of one without CuO NPs. Moreover, the power conversion efficiency of the ZnO DSSCs decreases with the increase of CuO NPs size.

Keywords: CuO nanoparticles, dye-sensitized solar cells, laser ablation, ZnO DSSCs

Speaker: Ms Anongnart Sonthila

51 Effect of Electromagnetic Fields on oil Palm Germination

Oil palm has widely been grown in Southern Thailand. Nowadays, it has been become an important economic plant. The oil from different varieties are used for bio-energy and industrial uses and also for human consumption. However, production of young oil palm trees is still limited and the plants are expensive because it takes up to 8 months for germination to occur and the germination percentage is only about 60 %. The slow germination rate and the high failure rate leads to additional costs because it makes disease control much more difficult. Electromagnetic Fields (EMFs) are known to increase overall percentage germination and shortens the incubation time of several plant species. We therefore present a physical method to stimulate oil palm germination by treating seeds with EMF. Oil palm seeds were exposed to EMF fields of 100mT to 250 mT and compared to controls. The treatments also were done for different period of times varying from 30 min to 5 hrs. The treated seeds were placed in germinators and sprayed with magnetically treated water. Germination percentages improved on seeds exposed to EMF and the time before germination decreased compared to the controls. The seeds which were exposed to EMFs at of 200 mT for 4 hrs started initial primary root at 8 days after magnetic treatment. There was 30% germination after 8 days incubation and 100% germination after 35 days. The results indicated that electromagnetic fields significantly shorten the time taken for oil palm seeds to germinate and greatly increases the proportion of seeds that do germinate. It reduces germination time of oil palm seeds from 8 months to 8 days and provides very high percentage of germination.

Speaker: ผศ.ดร. ชดาภัษท สุดศิริ (Prince of Songkla University)

52 Effect of Membrane Tension on Physical Properties of Niosome Bilayers: A Molecular Dynamics Study

Molecular dynamics simulations of niosome bilayer were performed to investigate its physical properties such as area per lipid, volume, thickness, lateral diffusion coefficient, and lipid structural order. The physical properties were computed in the membrane tension ranging from 0 to 15 dyn/cm. All simulations were carried out at the constant temperature of 300 K by using Gromacs package 5.1.2. We found that an increase in membrane tension results in a decrease in the bilayer thickness, area per lipid, volume and lateral diffusion. These results suggest that membrane tension causes significant change not only in the physical properties but also in the stability of noisome formation.

Keywords: Niosome Bilayer, Molecular Dynamics, Surface Tension, Membrane Thickness, Diffusion

Speaker: Ms Saowalak Somjid

53 Effect of MnO$_2$ morphology on electrochemical capacitance of supercapacitor electrode

In this study, different surface morphologies of MnO$_2$ (rod, wire, urchin and tube-like MnO$_2$) with an $\alpha$-phase crystalline structure were synthesized via a hydrothermal process by adding various reagents. The crystalline structure and morphology were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. In addition, the electrochemical properties were measured using cyclic voltammetry (CV) and galvanostatic charge/discharge (C.D.) in 1 M Na$_2$SO$_4$ aqueous solution. The specific capacitance of rod, wire, urchin and tube-like MnO$_2$ were about 110.20, 73.49, 53.80 and 64.31 F g$^-$$^1$. Especially, the rod-like MnO$_2$ exhibits a highest capacitance of 110.2 F g$^-$$^1$ at the current density of 0.5 A g$^-$$^1$ due to its smallest size.

Speaker: Mr Authit Phakkhawan (Khon Kaen University)

54 Effect of sputtering power on the properties of co-sputtered Zr-Ti-W metal alloy thin films

The Zr-Ti-W metal alloy thin films were fabricated by co-sputtering technique at room temperature. The effect of sputtering power on the thin film properties was investigated by varied power as 100, 200 and 300 W at the constant deposition time. The thickness and surface morphology of thin films were characterized by field-emission scanning electron microscope (FE-SEM) and atomic force microscope (AFM), respectively. The composition of Zr-Ti-W thin films was also analyzed by energy diffraction spectroscopic (EDS). Moreover, the crystallographic of the samples was determined by X-ray diffraction technique (XRD). The results showed that the Zr-Ti-W metal alloy thin films exhibited low surface roughness, amorphous structure, and the compositions of the element were related with the sputtering power.

Speaker: Mr Rattanachai Kowong

55 Effect of Surfactant Concentration to Aggregations of Nanogold Particles.

This research presents a study of aggregation of colloidal gold nanoparticles using 400 nm diameter gold nanoparticles mixed with a surfactant (Plantacare 2000) at various concentrations. When observed under a microscope, we found that the nanoparticles aggregated to form nearly spherical clusters at the beginning of the formation, and then sedimented to the bottom of the container. These clusters moved with Brownian’s motion and collided with each other in the horizontal plane, forming branch-like clusters in 2D. The appearance and size of the clusters were different depending on the concentration of surfactant. The clusters’ size and appearance were rarely changed after mixing with surfactant for 90 minutes, and we found that the cluster’s shapes were nearly spherical at low surfactant concentration (c = 0.25%). At surfactant concentration between 0.50% - 5.00%, the aggregates formed branch-like clusters with skinnier branches and smaller sizes at higher surfactant concentration. Moreover, we also found that, at surfactant concentrations between 2.50% - 5.00%, nanoparticles and aggregates stuck to the bottom of the glass container quickly and rarely moved after 10 minutes. At c = 0.25%, the 2D fractal dimension of the aggregates was measured to be D = 1.88 ± 0.04, since the aggregates were nearly spherical. The fractal dimension decreased to the minimum of D = 1.50 ± 0.12 at c = 1.50%, similar to D ~ 1.45 found in diffusion-limited cluster aggregation (DLCA). At surfactant concentration above 1.50%, the fractal dimension increased until it reached the value of D ~ 1.66 at c = 5.00%.

Speaker: Ms Methawee Duangthanu

56 Electrical properties and gas sensing properties of TiO$_2$/GO nanocomposites for CO$_2$ sensor application

Titanium dioxide (TiO$_2$) nanostructures were prepared by microwave assisted and varying time. The morphology of TiO$_2$ nanostructures were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD), electrical and gas sensing properties. SEM images revealed nanoparticles cluster of prepared products. XRD patterns showed anatase phase of TiO2 with peak of (101), (004), (200), (105), (211) and (204). The I-V characteristics exhibited the behavior of the ohmic and diodes materials. The sensitivity was measured under CO$_2$ atmosphere showed high sensitivity of TiO$_2$/GO composites in 60 second at 2.54.

Speaker: Ms Pitchanunt Chaiyo

57 Electrical Properties of Ultra-thin TiO$_2$ Compact Layer on FTO for Perovskite Solar cells

A TiO$_2$ compact layer or blocking layer plays a crucial role in a hybrid organic-inorganic lead halide perovskite solar cells because it can prevent the carrier recombination at the interface of fluorine-doped tin oxide (FTO) and perovskite layers. There are many methods to fabricate this layer such as spray pyrolysis or spin-coating which is solution-based synthesis that is difficult to avoid pinholes in the surface of the blocking layer. In this work, TiO$_2$ blocking layers are fabricated by radio-frequency (RF) magnetron sputtering using Ti metallic target with O$_2$ partial pressure in Ar atmosphere on FTO coated glasses. The controlled parameters for the deposition of TiO$_2$ compact layer are RF power, O$_2$ partial pressure, deposition time and annealing time. The optimization of the TiO$_2$ compact layers are found from the diode I-V characteristics between the TiO$_2$/FTO interfaces. The FESEM images as well as optical spectroscopy are used to observe the physical appearance and the optical transmission, respectively.

Speaker: Ms Ramon Songtanasit (Department of Physics, Faculty of Science, Chulalongkorn University)

58 Enhance of hydrophilicity property for gas separation membrane by DC plasma

Preparation and surface modification of Polysulfone (PSF) membranes by DC plasma were conducted in order to improve membrane hydrophilicity and gas permeation efficiency. Different type of oxygen (O$_2$), Argon (Ar), Argon (Ar)/oxygen (O$_2$) mixture plasma and plasma sequence of O$_2$ and Ar gasses were employed to modify the membrane surfaces. Characteristics of membrane samples were evaluated through various analytical techniques. Membrane hydrophilicity was determined by water contact angle (WCA) measurement while Fourier transform infra-red (FTIR) spectroscopy was used to analyze the functional groups on the modified surface membrane. We studied the aging condition by measuring the WCA of the plasma-treated surface membrane that recovering to the original condition. For gas separation, the result shows that the permeability of CO$_2$ is higher than of CH$_4$ that were explained by electronic properties, polarizability and quadrupole moment. Result also indicated that while the gas permeability of the treated membrane by DC plasma was enhanced but the selectivity of CO$_2$/CH$_4$ show a lower performance.

Speaker: Mrs Soraya Ruangdit (-)

59 Fabrication and Physical Properties of Titanium Nitride/Hydroxyapatite Composite on Polyether Ether Ketone by RF Magnetron Sputtering Technique

Titanium nitride coatings have been used very successfully in a variety of applications because of their excellent properties, such as the high hardness meaning good wear resistance and also used for covering medical implants. Hydroxyapatite is a bioactive ceramic that contributes to the restoration of bone tissue, which together with titanium nitride may contribute to obtaining a superior composite in terms of mechanical and bone tissue interaction matters.
This paper aim to optimize deposition conditions for films synthesis on PEEK by varying sputtering parameters such as nitrogen flow rate and direction, deposition time, d-s (target-to-substrate distance) and 13.56 MHz RF power. The plasma conditions used to deposit films were monitored by the optical emission spectroscopy (OES). Titanium nitride/Hydroxyapatite composite films were performed by gas mixture with nitrogen and argon ratio of 1:3 and target-to-substrate distance at 8 cm. The gold color, as-deposited film was found on PEEK with high hardness and higher surface energy than uncoated PEEK.

Keyword: Titanium Nitride, Hydroxyapatite, RF magnetron sputtering, Polyether ether ketone

Speaker: Wasin Nupangtha (Chiang Mai University)

60 Fabrication of carbon sphere film as a supercapacitor electrode

In this work, carbon sphere films at different growth temperature of 180, 200 and 220°C were synthesized by 10 hrs hydrothermal process from glucose to apply for supercapacitor electrode. The carbon sphere films were washed and filled by DI water for several times. Finally, they were kept it in an oven at 80°C to dry. Crystal structure and film morphology were analyzed by X-ray diffraction, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Supercapacitor performance were studied by cyclic voltammetry (CV), charge-discharge (CD) and electrochemical impedance spectroscopy (EIS). The specific capacitance of carbon sphere electrode grown at 180, 200and 220°C are about 12.6, 3.3 and 2.9 F/g, respectively. The highest specific capacitance was achieved at 180°C. The dependence of growth temperature on film specific capacitance will be discussed in detail later.
Keywords: carbon sphere, supercapacitor, glucose, charge/discharge

Speaker: Ms Suklitta Thongkhem (Khon Kaen University)

61 First-principles study of H$_2$ adsorption on two-dimenstional C$_2$N sheet

First-principles calculations based on density functional theory (DFT) have been performed to study the adsorption of molecular H$_2$ on the graphene-like material C$_2$N. The possible adsorption sites on top of bonds, on carbon atom and nitrogen atom and the center of C-C hexagon and the C-N hexagon are considered. The adsorption energies for each site are calculated and are found to be in the physisorption regime. We find that the most favorable site of H$_2$ is above the center of C-N hexagon. In addition, we demonstrate that inclusion of the Van der Waals interactions through the DFT-D2 method via the generalized gradient approximation (GGA) functional gives the consistent trend of H$_2$ adsorption with that obtained via the local-density approximation (LDA) functional. The effects of Van der Waals interactions on the adsorption energies and equilibrium distance between H$_2$ and C$_2$N sheet are discussed.

Speaker: Mr Pongdet Netrattana (Department of Physics, Faculty of Science, Kasetsart University)

62 Fission Product Behavior in High-Temperature Water: CsI vs MoO$_4$

Fission product behaviors of Cs, a major element released in a severe nuclear accident, still remain unclear. The question frequently addressed is whether Cs released will be in the form of CsMoO$_4$ or CsOH. This is a challenging issue since it has been demonstrated that the reaction between CsMoO$_4$ and water leading to CsOH production is thermodynamically favored. The present research aims at investigation of CsOH generation through this chemical channel. A high-temperature setup with a flow system based on the cooling system of a water-cooled nuclear reactor has been assembled. The reaction between aqueous solutions of CsI and NaMoO$_4$ in a high-corrosion-resistant hot cell (Hastelloy) has been studied up to 80$^o$C both in air and deoxygenated system. The products have been characterized using XRD and FTIR.

Speaker: Dr Kotchaphan Kanjana (Thailand Institute of Nuclear Technology)

63 Flipped Classroom Enhances Students’ Performance in Physics Learning

A flipped classroom is an instructional strategy and a type of blended learning that reverses the traditional learning environment. Instead of spending entire periods watching a lecture, students watch lectures online outside of class time and use class time to do activities. The 35 pre-engineer students had been taught by flipped classroom on the topics of work and energy in Physics course. The study shows that the use of the flipped classroom in the learning process enhances students’ motivation and improves their performance more than traditional classroom

Speaker: Mr Prakasit Changsuphan

64 Fractal dimension of synthesized sound wave

An important aspect of musical structure that allows discrimination between different sounds is the timbral characteristic. Although, there has been significant interest in the application of fractal theory as a tool for the analysis of musical structure, no such study has been done to investigate timbre on physical modeling sound synthesis. In this paper, we examine the changes of timbre and estimate fractal dimension of musical signals which synthesizes by three physical modeling methods: Karplus-Strong algorithm, functional transformation, direct numerical simulation. The results indicate that fractal analysis can identify the timbral characteristic regarding the underlying physical factors that distinguish the different between sounds.

Speaker: Mr Manorth KANJANAPEN (Department of Physics, Faculty of Science, Kasetsart University)

65 Frequency Distribution of Specific Activities and Radiological Hazard Assessment in Surface Beach Sand Samples Collected from Bangsaen beach in Chonburi Province, Thailand

The specific activities of natural radionuclides ($^4$$^0$K, $^2$$^2$$^6$Ra and $^2$$^3$$^2$Th) in 50 surface beach sand samples collected from Bangsaen beach in Chonburi province in the easthern region of Thailand, were measured and evaluated. Experimental results were obtained by using a high-purity germanium (HPGe) detector and gamma spectrometry analysis system in the special laboratory at Thailand Institute of Nuclear Technology (Public Organization). The IAEA-SOIL-375 reference material was used to analyze the concentration of $^4$$^0$K, $^2$$^2$$^6$Ra and $^2$$^3$$^2$Th in all samples. It was found that the specific activities of $^4$$^0$K, $^2$$^2$$^6$Ra and $^2$$^3$$^2$Th were ranged from 510.85 - 771.35, 8.17 - 17.06 and 4.25 - 15.68 Bq/kg. Furthermore, frequency distribution of the specific activities were studied, analyzed and found to be the asymmetrical distribution by using a statistical computer program. Moreover, four radiological hazard indices for the investigated area were also calculated by using the median values of specific activities of $^4$$^0$K, $^2$$^2$$^6$Ra and $^2$$^3$$^2$Th. The results were also compared with the Office of Atoms for Peace (OAP) annual report data, Thailand and global radioactivity measurement and evaluations.

Speaker: Nopparit Changkit

66 Gamma Ray Evaluation of Fast Neutron Irradiated on Topaz from Sri Lanka by HPGe Gamma Ray Spectrometry

The purpose of this study was to evaluate the radionuclide concentrations of London blue topaz after fast neutron irradiation. The London blue topaz was obtained from Sri Lanka which classified into dark and light colors in the shape of an oval and rectangle with small, medium and large size. The optical property and radionuclide concentrations of London blue topaz have been examine by UV - Visible spectroscopy and HPGe gamma ray spectrometry, respectively. The UV - absorption spectra of topaz was taken in the range of 300 to 800 nm at room temperature. The results showed that the absorption peak of topaz was observed with only broad peaks in the range of 550 to 700 nm and 630 nm that correlated to the O - center in hydroxyl sites which substitutes for fluorine in topaz structure. The radioactivity of dark and light colors in the shape of an oval and rectangle London blue topaz was in the range of 1.437 $±$ 0.014 to 21.551 $±$ 0.037 nCi/g (oval dark), 2.958 $±$ 0.031 to 6.748 $±$ 0.054 nCi/g (oval light) and 2.350 $±$ 0.014 to 43.952 $±$ 0.088 nCi/g (rectangle dark), 1.442 $±$ 0.023 to 6.748 $±$ 0.054 nCi/g (rectangle light), respectively. The decay rates of $^4$$^6$Sc, $^1$$^8$$^2$Ta and $^5$$^4$Mn isotopes created by irradiation showed that the time decay of the radioactive element depended on the size of the topaz so increased with decreasing the size of topaz. Moreover, the size of topaz also affect the absorption coefficient. This study is applied to predict time of residue dose of topaz for enhancement colorless topaz by neutron radiation treatment.

Speaker: Ms Kanokwan Boonsook (Department of Physics, Faculty of Science, KMUTT)

67 Gas Sensing Response of Nickel Doped Calcium Copper Titanate Thin Films Synthesized by Sol-gel Method

Nickel-doped calcium copper titanate (CaCu₃Ti₄O₁₂: CCTO) thin films were synthesized by a sol-gel method. All films were spin-coated with four layers on silicon and alumina substrates, and each film layer was annealed at a fixed annealing temperature of 800 °C. The obtained samples with different doping concentrations (0-7.27 wt%) were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), energy dispersive X-ray spectroscopy (EDX), and X-ray photoe-lectron spectroscopy (XPS). From XRD patterns, CCTO and Ni-doped CCTO films were cubic perovskite phase with small amount of impurity phases of TiO₂. The film thickness of approximately 320-600 nm were obtained using FE-SEM. In addition, 7.27 wt% Ni-doped CCTO film showed more porosity than other films. The film gas sensors were probed to measure gas sensing responses towards different types of gases such as NO₂, H₂, NH₃, H₂S and ethanol gas. All samples performed the best selectivity towards H₂S. Compared with other films, the 7.27 wt% Ni-doped CCTO film sensors exhibited the highest response of 112 for 10 ppm of H₂S with the optimum temperature of 250 °C.

Speaker: Ms Arisara Boontum (Department of Physics, Faculty of Science, Chulalongkorn University 254 Phyathai Road, Patumwan, Bangkok Thailand. 10330)

68 Hardness Enhancement on Stainless Steel Surface by Coating Graphene Film Using Thermal Chemical Vapor Deposition

Stainless steel is steel alloy consisting of many elements including iron (majority), chromium, nickel and sulfur. Stainless steel has been widely utilized because it is more effective in terms of resistance of corrosion, rust or stain than ordinary steel. However, the electrical conductivity and surface hardness of stainless steel are not high. These disadvantages limit the engineering application of stainless steel from wide range to some range. Graphene is an allotrope of carbon, in which carbon atoms are arranged into a one-atom-thick honeycomb lattice. Graphene has a variety of exotic properties such as great electronic properties and excellent mechanical properties. In this report, therefore, we have investigated hardness enhancement on stainless steel surface after coating graphene film by thermal chemical vapor deposition. The results show the hardness of stainless steel after coated with graphene is ~10 times higher than original stainless steel.

Speaker: Akkawat Ruammaitree

69 Hydrophobic thiol-ene surfaces fabricated via plasma activation and photo polymerization

Alumina, such as glazed alumina for electrical insulator, operated in an open field subjects to a very harsh condition; resulting in lifetime shortening. Coating hydrophobic layer on alumina surface can help prolonging its lifetime. In this study, 25x25 mm alumina sheets were used as substrates. The hydrophobic composite polymers were prepared by (3-mercaptopropyl) trimethoxysilane (MPTMS), 2,4,6,8-tetramethyl-2,4,6,8 tetravinylcyclotetrasiloxane (TMTVSi), pentaerythritoltetra(3-mercaptopropionate)(PETMP), 2,2-dimethoxy-2-phenylaceto phenone(photoinitiator) and heptadecafluorodecylmethacrylate(HEFDMA) via the thiol-ene reaction. The alumina sheets were first activated by dielectric-barrier discharge plasma to improve its adhesion.All the polymers were found to optimize at the ratio of (MPTMS:TMTVSi:PETMP:HDFDMA) to 4:2:1:2 for coating on the alumina substrate. To enhance polymerization, 2,2-dimethoxy-2-phenylaceto phenome was also used as a photoinitiator A proper mixing sequence in the thiol-ene reaction results in film with excellent surface retention after prolong soaking in solvent such as acetone. FTIR shows that S-H and C=C functional groups have significantly changed after photopolymerization and thermally cured. The static contact angle increase from mere 53.0$^{\circ}$$\pm$1.5$^{\circ}$ of the uncoated substrate to 120.0$^{\circ}$$\pm$1.2$^{\circ}$ after coating. SEM shows the film with clear appearance of a few-micron thick. Under AFM, the coated surface roughness was about 9.3 nm with evenly distributed spikes of a few nanometer in height. The cross-cut test also confirmed the film was very smooth and none of the square of the films detached.

Speaker: Peera Champathet

70 Improved Efficiency of Polymer Solar Cells by mean of Coating Hole Transporting Layer as Double Layer Deposition

Polymer solar cells is one of the promising technologies that gain tremendous attentions in the field of renewable energy. Optimization of thickness for each layer is an important factor determining the efficiency of the solar cells. In this work, the optimum thickness of Poly(3,4-ethylenedioxythione) : poly(styrenesulfonate) (PEDOT:PSS), a famous material widely used as hole transporting layer in polymer solar cells, is determined through the consideration of device’s power conversion efficiency (PCE). The structure of ITO/PEDOT:PSS/PCDTBT:PC$_\text{71}$BM/Tio$_\text{x}$/Al was employed to fabricate the solar cells by rapid convective deposition. The thickness of PEDOT:PSS layer was varied via the deposition speed. Furthermore, double layer deposition of PEDOT:PSS was introduced as an approach to improve solar cell efficiency. To confirm the enhancement of solar cell efficiency, PEDOT:PSS films were characterized by the combinations of microscopic and spectroscopic techniques. The results obviously reveal that, with the optimized thickness, the PCE of the device reaches 4.03%. Interestingly, using double layer deposition of PEDOT:PSS shows the ability to enhance the performance of the solar cells to 6.12% under simulated AM 1.5G illumination of 100 mW/cm$^2$.

Speaker: Ms Teantong Chonsut (College of Nanotechnology, King Mongkut’s Institute of Technology Ladkrabang)

71 Improving of QRS complex detection in ECG signal Using Combination of Fourier Transform and Wavelet method

Electrocardiography (ECG) signal is very important signal for identifying heart disease. It composes of five main characteristics which can be specified by the P-QRS-T signals. One of the most important segment in the signal is the QRS complex because it is the heart activity that electricity run all over heart which can tell many heart disease. There have been many studies on identifying the complex location and interval in the ECG. For instance, in field of physics, electronic circuit simulations were used to image QRS complex for identifying heart disease. However, in complex simulation, there requires primitive knowledge where the location of QRS complex, which is unknown parameter and has to guess from visual inspection. On the other hand, in the field of signal processing area, a regular used technique to achieve this QRS characteristic is the application of the wavelet transform to identify QRS signal. Although, this technique has proved that it has high accuracy in detecting QRS complex, it too bases mainly on trial and error method where one firstly need to estimate and guess where about the QRS is and how long the QRS interval lasts. Therefore, to overcome this problem, this study aim to provide an automate technique to replace the estimating module by firstly coarse scanning for QRS complex position using Fourier Transformation. After that, the wavelet transform will be used as fine scanner to specify more precise QRS complex position. Twenty ECG signals with various characteristic, such as shockable rhythms and non-shockable rhythms, were investigated in this work. To detect QRS complex, Fourier Transform was used to identify fundamental frequency range of ECG by choosing the ones with comparatively high amplitudes. After that, these frequencies were added to Wavelet method to identify the range of interest for extracting Wavelet coefficients. After that, the Wavelet function was used to transform ECG signal and mark the position of QRS complex. From our preliminary results, the Fourier Transform can extract unique frequencies for each type for the Wavelet to locate QRS complex position, where more than 98% accuracy on the results was obtained. Note that without our proposed Fourier Transform part, using only Wavelet Transform in some ECG type gives less than 80% accuracy. This implies that our combined Fourier and Wavelet Transforms technique in detecting QRS complex position in normal and abnormal ECG signals, and may help to specify heart diseases with more reliability and efficiency. Therefore, one can elaborate our proposed module to design automatic heart disease diagnostic system, which can benefit medics outside heart diagnostic field for initialize emergency treatment of sudden heart attack.

Speaker: Jutarop Reungyos

72 In-house development of neutron moisture gauge for field measurement

The measurement of moisture content in soil is based on the principle of neutron back scattering. In this principle, when fast neutrons emitted from a radioactive source collide with hydrogen atoms their energies are much greater reduced than colliding with other atoms. The number of slowed down neutrons, hence, represents the number of hydrogen atoms present in the vicinity of the source. As water is the main contributor of hydrogen atoms in a soil medium, the moisture content in soil, therefore, can be measured based on this principle. An in-house developed probe containing a source of fast neutrons and a slow neutron detector was inserted into soil at different depths under the ground level. The probe was made of high density polyethylene and connected to a suitably calibrated detection system by a single cable. The moisture content was determined from the slow neutron count rate. The results of field measurement tests were reported and discussed.

Speaker: Ms Parichat Sinkaew (Department of Physics, King Mongkut’s Institute of Technology Ladkrabang)

73 Influence of Thermal Annealing Process on Vanadium Oxide Thin Films for Metal-Insulator Transition Enhancement

Metal-insulator transitions (MIT) are reversible changes in the conductivity of materials when the temperature above or below the transition point, which are the smart transitions in advanced material. Vanadium oxide (V$_\text{x}$O$_\text{y}$) demonstrated excellent MIT characteristics at the transition temperature (T$_\text{c}$) due to the lattice distortion. However, V$_\text{x}$O$_\text{y}$ has many phases such as V$_\text{2}$O$_\text{5}$, V$_\text{2}$O$_\text{3}$, VO$_\text{2}$, VO, which have the different transition temperature. In this work, we study the influence of an annealing process to improve the MIT of V$_\text{x}$O$_\text{y}$ thin film on glass substrates. V$_\text{x}$O$_\text{y}$ thin films were prepared by the pulsed DC magnetron sputtering technique at room temperature by various gas ratios between Ar and O$_\text{2}$. Then, the crystal structures of V$_\text{x}$O$_\text{y}$ thin films were investigated by X-ray diffraction. X-ray diffractrograms of as deposited V$_\text{x}$O$_\text{y}$ thin films did not show the crystallinity index of material. To improve the MIT or the crystalinity of V$_\text{x}$O$_\text{y}$ films, the controlled ambient annealing process was applied to deform grains and recrystallize of the material. Consequently, as deposited V$_\text{x}$O$_\text{y}$ thin films were annealed under control N$_\text{2}$ pressure, and the temperature was set at 400$^°$C to avoid the deformation of thin film at the high annealing temperature. After annealing process, the MIT characteristics of V$_\text{x}$O$_\text{y}$ thin films were measured by four points probe technique between 30-150 $^°$C. Surprisingly, the V$_\text{x}$O$_\text{y}$ thin films exhibit the MIT behavior in two orders of magnitude. We found the formation of V$_\text{2}$O$_\text{5}$ from XRD patterns of thin films, and other phases such as V$_\text{2}$O$_\text{3}$, VO$_\text{2}$ also discovered. Moreover, the Raman spectra of thin films show the vibration modes of V$_\text{2}$O$_\text{5}$ to confirm the effect of annealing process on the V$_\text{x}$O$_\text{y}$ crystal formation. Our preliminary study is promising method to improve the crystal formation of V$_\text{x}$O$_\text{y}$ thin film and enhance the MIT for further electronics applications.

Speaker: Mr Sukittaya Jessdaluk (College of Nanotechnology, King Mongkut’s Institute of Technology Ladkrabang, Chalongkrung Rd., Ladkrabang, Bangkok 10520, Thailand)

74 Influence of Under-layers morpholgy on Structural and Magnetic Properties of Sputtered Co81Pd19 Film.

Sputtered Co81Pd19 films with thickness of about 60 nm were deposited on various under-layers (Al, Co, Cr, Cr and Ni) and on glass substrate. Structural, morphological and magnetic properties of Co81Pd19 films were investigated. All of prepared films showed CoPd (FCC) phase in (111) plane. Co (HCP) phase in (200) direction was observed in the films deposited Al, Cr and Ni under-layer and on glass substrate whereas the film on Co-under-layer exhibited Co (HCP) phase in (201) plane. AFM images revealed that the film on Al and Co under-layers exhibited the maximum roughness with highest grain size and the minimum roughness with lowest grain size, respectively. Both parallel and perpendicular maximum coercive field were found in the film on Ni under-layer and the film on Co-under-layer film showed the highest saturation magnetization both in-plane and out-of-plane measurements. These results confirmed that the structural and magnetic properties of sputtered Co81Pd19 film was affected by under-layer surface roughness and morphology by virtue of particle size and distribution on the under-layer film surface.

Speaker: Pairin Ponchaiya

75 interference of two vortex beams with different topological charge numbers

Optical vortex is a mode of light whose phase distribution varies as e$^{im\phi }$, where m is called the topological charge of the vortex and ${\phi}$ is an azimuthal angle in the plane perpendicular to the propagating direction. The vortex beam of charge m carries an orbital angular momentum of mℏ and has its application in manipulating micrometer-sized particles. A common method to detect topological charges of optical vortices is interference with a tilted Gaussian beam. In this work, we study the interference pattern of two vortex beams with different topological charges, created by spatial light modulators (SLMs). We find fork-like fringes similar to those observed from the interference between a vortex and a Gaussian beam. The fringe difference between the top and the bottom of the fork equals the difference between the topological charges of the two vortices, as predicted by the theory. When the topological charges are the same, the fork pattern disappears. We suggest the result can be used to detect topological charges of vortex beams.

Speaker: Ms Suvipak Chumdaeng (Department of Physics, Faculty of Science, Kasetsart University)

76 Investigating Student understanding of Simple harmonic motion

This study aimed to investigate students’ understanding and develop instructional material on a topic of simple harmonic motion. Participants were 80 students taking a course on vibrations and wave on the 2nd semester of an academic year 2016. A 20-question conceptual test and tutorial activities had been developed from previous research findings and evaluated by three physics experts in teaching mechanics before using in a real classroom. Data collection included both qualitative and quantitative methods. Item analysis and whole-test analysis were determined from student responses in the conceptual test. As results, most students had misconceptions about restoring force and they had problems connecting mathematical solutions to real motions, especially phase angle. Moreover, they had problems with interpreting mechanical energy from graphs and diagrams of the motion. These results were used to develop effective instructional materials to enhance student abilities in understanding simple harmonic motion in term of multiple representations.

Speaker: Pornrat Wattanakasiwich

77 Investigation of L-H-L Transitions Criteria and Hysteresis Based on Bifurcation Concept

Investigation of L-H-L Transitions Criteria and
Hysteresis Based on Bifurcation Concept

A. Dang-Iad$^{1*}$ , T. Onjun$^2$ and B. Chatthong$^1$ ,
1Department of Physics, Faculty of Science, Prince of Songkla University,
Hat Yai, Songkhla, Thailand
2 Former Sirindhorn International Institute of Technology, Thammasat University, Pathum Thani, Thailand

This research aims to study the criteria for the forward L-H transition and backward H-L back transition as well as hysteresis depth in tokamak fusion plasmas based on bifurcation concept. Three transport equations including thermal, particle and toroidal momentum density are solved simultaneously, resulting in the prediction of plasma pressure, plasma density and toroidal velocity profiles at steady state. The transport effects include both neoclassical and anomalous transport with velocity shear dependent suppression function. The results show that the flux (thermal/particle/momentum) versus gradient (pressure/density/velocity) space exhibits s-curve bifurcation nature in which a forward L-H transition requires higher flux than that of the backward H-L transition, hence hysteresis behaviors. In addition, it is found that ratio of the plasma flux at the forward L-H transition over the backward H-L transition depends sensitively on thermal, particle and toroidal momentum neoclassical and anomalous transports.

Keyword: bifurcation, hysteresis, transport barrier

Speaker: Mr APISIT DANG-IAD

78 Isotopic Composition of Precipitation at Ongkharak District, Nakhon Nayok Province

In this work the utilization of nuclear hydrological instruments using Liquid Scintillation Counter (LSC) and laser absorption spectrometer (Cavity Ring-Down Spectrometer, CRDS) were employed. All samples from the precipitation were treated for isotopic instruments. Tritium values were analyzed with electrolytic enrichment and LSC while deuterium and oxygen-18 were calculated on CDRS. As a result, tritium values ranged 0.6-13.3 TU (tritium unit), deuterium values are between -76.44 and -7.5 ‰ (per mil) and oxygen-18 values show -10.67 to -2.42 ‰. The data of tritium and stable isotope can be used to input data for studying the dynamics of groundwater in Ongkharak area.

Keywords: Isotope hydrology, tritium, stable isotope

Speaker: Mr Chakrit Saengkorakot

79 Learning Particle Physics with DIY Play Dough Model

The scientists once believed an atom was the smallest particle, nothing was smaller than this tiny particle. Later, they discovered an atom which consists of protons, neutrons and electrons, and they believed that these particles cannot be broken into the smaller particles. According to advanced technology, the scientists have discovered these particles are consist of a smaller particles. The new particles are called quarks and gluons which we called fundamental particle. Atomic structure cannot be observed directly, so it is complicated for studying these particles. The aim of the study are (1) to help students get more understanding, the researcher made particles model from “Play Dough”, (2) to develop creativity in students and cooperative learning among students.

Speaker: Ms Thittima Thunyaniti (Faculty of Science, Ubonratchathani University)

80 liposomes fabrication using vortex rings generated microfluidic device

Liposomes are phospholipid vesicles enclosing aqueous solution. Liposomes are used in many biomedical applications such as drug delivery and artificial cell models. Giant unilamellar vesicles (GUVs) fabrication using vortex ring in microfluidic device offers advantages over traditional GUVs fabrications such as rapid fabrication and controllable uniform vesicle sizes distribution. The phospholipid bilayer interface inside microfluidic reservoir is disturbed by collision of vertex rings producing by pulse injection in microchannel, leading to formation of droplet enclosed by phospholipid bilayer. Computational fluid dynamics simulation was carried out to vary phospholipid bilayer interface area and injection pulsing parameters in order to achieve desirable vortex ring sizes.

Speaker: Mr Sorawit Sanin (Department of Physics and Materials Sciences Chiang Mai University)

81 Liquid absorption using 3D carbon nanofiber scaffolding derived from bacterial cellulose

ABSTRACT
3D carbon nanofiber scaffolding was produced from the pyrolysis of freeze-dried (FD) bacterial cellulose (BC). The thermogravimetry and differential thermal analysis (TG/DTA) showed the weight loss of BC during the pyrolysis process. The X-ray diffraction technique showed the high crystallinity of the FD-BC and the high amorphousness of the carbon nanofibers. Both FD-BC and the pyrolyzed carbon nanofibers consisted of tiny fibers with the size of<100 nm. The liquid absorption capacity using FD-BC and carbon nanofibers was tested by measured the weight before and after absorption. It was found that the FD-BC was good for water absorption due to the hydrophilic nature of the sample. For the organic solvent, ethanol, methanol, benzene, and palm oil, the hydrophobic carbon nanofibers had the absorption capacity of nearly hundred times of their own weight.

Speaker: Mr Surachat Sombat (Khon Kaen University)

82 Low Cost and Disposable Lab on a Chip

In this research, a low cost and disposable lab on a chip was designed and fabricated by screen printing. The chip was designed with integrated digital microfluidic microchip and electrochemical detector on single plate substrate. For the design, the chip consist of T-junction EWOD digital microfluidics microchip for merging buffer reagent and analyze droplets and an electrochemical detector at the end of T-junction EWOD. Both parts were fabricated by screen printed technique for supporting low cost manufacturing process. The EWOD microchip consists of silver paste for electrodes layers and PDMS for dielectric and Teflon® AF hydrophobic layers. Three electrodes of electrochemical detector consists of a carbon paste working electrode and a carbon paste counter electrode, and silver/silver chloride paste reference electrode for rapid analysis with minimal reagent consumption. In experiment, the electrochemical detector combine with EWOD microchip was tested to study possibility of moving (merging and transporting) ionized droplet and samples (buffer and analyzed droplet) on the microchip. For analysis, the EWOD chemical detector was analyzed for nicotinamide adenine dinucleotide for rapid analysis with minimal reagent consumption.

Speaker: Mr Anan Saenkhamai

83 Measurement and Analysis of Specific Activities of Radionuclide 40K, 226Raand 232Th in Beach Sand Samples from Talo kapo beach Yaring DistrictinPattani Province using Gamma Ray Spectrometry

The Specific Activities of $^{40}$K, $^{226}$Ra and $^{232}$Th were determinet for 30 beach sand samples collected from Talo kapo beach Yaring District in Pattani Province. Experimental results were obtained by using a high-purity germanium (HPGe) detector and gamma spectrometry analysis system. Gamma ray radioactive standard sources $^{137}$Cs and $^{60}$Co ware used to calibrate the measurement system. The IAEA-SOIL-6 reference materials obtained from the International Atomic Energy Agency Were also used to analyze and compute the 40K, $^{226}$Ra and $^{232}$Th specific activity in all 30 beach sand samples, respectively. The measuring time of each samples is 10,000 seconds. It was found that specific activity range from 1805.37 – 3,323.05 Bq/kg for $^{40}$K, 40.96 – 2,137.36 Bq/kg for $^{226}$Ra and 38.63 – 4,329.28 Bq/kg for $^{232}$Th with mean values of 2,242.79 ± 117.40 Bq/kg, 250.18 ± 8.21 Bq/kg and 458.42 ± 7.68 Bq/kg respectively. Moreover, the results were compared with research data in the south of Thailand, the Office of Atoms fror Peace (OAP) annual report data and the recommended values which were proposed by United Nations Scientific Committee on the Effects of Atomic Radiation (UNSEAR, 1988. 1993, 2000)

Speakers: Ms Yameela Mhudchudchu (Department of Physics and General Science, Faculty of Science and Technology, Songkhla Rajabhat University), Ms Areeya Tamat (Department of Physics and General Science, Faculty of Science and Technology, Songkhla Rajabhat University), Ms Masae Masae (Department of Physics and General Science, Faculty of Science and Technology, Songkhla Rajabhat University), Ms Supeeya Pao-oh (Department of Physics and General Science, Faculty of Science and Technology, Songkhla Rajabhat University)

84 Mechanical properties of cement paste containing iron powder

Mechanical properties of cement paste containing iron powder
Nattapong Chuewongkam1, Panjasil Payakaniti2,Supree Pinitsoontorn1,2,3
1Department of Physics, Faculty of Science, KhonKaen University, KhonKaen 40002 THAILAND
2 Materials Science and Nanotechnology Program, Department of Physics, Faculty of Science, KhonKaen University, KhonKaen 40002, Thailand
3Integrated Nanotechnology Research Center, Department of Physics, Faculty of Science, KhonKaen University, KhonKaen 40002 THAILAND

Abstract
This research project studied the mechanical properties of the iron paste containing metal powder. The amounts of the iron powder additives were 10, 20, 30, 40, 50, 60 and 70% by weight of cement. Water to cement ratio was controlled by measuring workability. The universal testing machine as used to measure mechanical property. Which showed that adding iron powder enhanced the compressive strength of the cement paste. The microstructure was studied by using a scanning electron microscope. The correlation between microstructure and strength was discussed.

Keywords: Cement paste; Iron powder; Compressive Strength

Speaker: Mr Nattapong Chuewongkam (Department of Physics)

85 Microfluidic System for E.coli Electroporation

Electroporation is the technique in which external electrical field is applied across cells of interest to create pores on cell membrane when the voltage across the cell membrane is high enough. Electroporation is commonly used to deliver exogenous reagents such as genes, drugs, and nanoparticles for therapeutic purposes. In this work, microfluidic device was fabricated using Printed Circuit board technique. Several planar Indium Tin Oxide (ITO) electrodes shapes were attached on glass slide and microchannel was place between two electrodes in the longudinal direction. E.coli was used as a cell model in electroporation experiment. The 12- 50 AC voltage with 1,000 Hz frequency. Fluorescence dye was used for real time electroporation monitoring.

Speaker: Jongrak Sanglao (Chiangmai University)

86 Microstructure of CaCu$_3$Ti$_4$O$_{12}$/SrTiO$_3$ and CaCu$_3$Ti$_4$O$_{12}$/BaTiO$_3$ multilayered thin films grown on LaAlO$_3$ (100) substrates for dielectric tunability

CaCu$_3$Ti$_4$O$_{12}$(CCTO)/SrTiO$_3$(STO) and CaCu$_3$Ti$_4$O$_{12}$(CCTO)/BaTiO$_3$(BTO) films multilayered heterostructures were successfully synthesized on LaAlO$_3$ (LAO) (100) substrates via a sol-gel method. The annealing temperature was fixed at 800 °C for one hour for each deposition. Our films were deposited with conditions as follows; CCTO/CCTO/CCTO/CCTO, STO/STO/STO/STO, CCTO/STO/CCTO/STO (1L-CCTO/STO), CCTO/CCTO/STO/STO (2L-CCTO/STO), CCTO/CCTO/BTO/BTO (2L-CCTO/BTO) and CCTO/BTO/CCTO/BTO (1L-CCTO/BTO) on LAO substrates. From X-ray diffraction patterns, it was concluded that the CCTO, STO films and their multilayers deposited on LAO (100) substrates tend to be predominantly (h00) oriented, whereas BTO and its multilayers show polycrystalline orientations. Based on our analysis, CCTO films have a cubic structure with estimated lattice parameters of 7.376 Å (3.688 Å) and for STO with estimated lattice parameters of 3.888 Å, while LAO has a pseudo-cubic structure with a calculated lattice constant of 3.790 Å. Interestingly, the TiO$_2$ commonly presented as an impurity phase in CCTO films was suppressed in CCTO/STO multilayered films. The surface morphology and the interface layers of the films were characterized by FE-SEM technique. For electrical measurement, 1L-CCTO/STO and 2L-CCTO/STO have dielectric constants of 1000 and 820 at 100 kHz, respectively. The loss tangent values measured at the frequency above 10 kHz of both 1L and 2L-CCTO/STO films are approximately 0.07. Despite being stacked up with non-tunable dielectric materials, 1L-CCTO/STO thin films can be tuned in range of 1.6% at 10 kHz.

Speaker: Mr Wiwittawin Sukmas (Chulalongkorn University)

87 Minimization of the synthetic androgen 17Alpha-methyltestosterone hormone for sex reversal of Nile tilapia eggs using electrical technique

With the realization of widespread use of large quantities of sex reversal hormone of the synthetic androgen 17Alpha-methyltestosterone (MT) affect on the environment and the inefficiency and cost of the conventional techniques, the hormonal sex reversal of economic fish needs to modified to avoid the excess use of MT, lessen the duration of treatment and lower the cost of MT hormone used relative the conventional technique of sex reversal by the feed-fry hormone treatment. This work employs our expertise in electroporation of cells to enhance sex reversal in Nile Tilapia eggs to minimize 2,000 times consumption of the treatment and androgen hormone dose (less than 3,600 times) compared to the conventional feed-fry treated and immersion techniques. This novel technique using the transient high-intensity electric fields has potential since it is non-invasive, with no-stress acting on the membrane. The technique could be used to load cells with a variety of different molecules, either through simple diffusion in the case of small molecules, or through electrophoretically driven processes allowing passage through the destabilized membrane. The technique and equipment was designed for large-scale inductions of eggs suspensions (commercial farm in Thailand had requested order more than 1 million-induction eggs/week) rather than for individual eggs aimed at commercialization.

Speaker: Prof. Dr.Sakshin ฺBunthawin (Biotechnology of Electromechanics Research Unit, Science of Physics, Faculty of Technology and Environment, Prince of Songkla University, Phuket Campus )

88 Modification of Calcium Copper Titanate Thin Films by Adding Ag Compounds and their H2S Gas Sensing Response

Ag-doped CaCu₃Ti₄O₁₂ (CCTO) thin films with different doping concentrations were prepared by a sol-gel technique. Films were grown by depositing four layers of CCTO on alumina substrates followed by sputtering Au/Cr interdigitated electrodes to fabricate gas sensors. The films were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDX). The films have predominantly the perovskite CCTO crystal phase with very small amount of TiO₂ secondary phases. In this work, both undoped CCTO and Ag-doped CCTO thin films were tested for selective sensing to H₂S gas relative to NH₃, H₂, NO₂ and ethanol vapor. For characterizing gas sensing properties of the films, gas concentrations in the range of 0.2-10 ppm were used with operating temperatures ranging from 150 to 350 °C. When compared to undoped CCTO sensor, the Ag-doped CCTO sensors presented much higher response. The best sensitivity towards H₂S was found in 0.9 wt% Ag-doped CCTO film and at the optimum operating temperature of 250 °C. The highest response of the sensor based on the 0.9 wt% Ag-doped CCTO film to 10 ppm of H₂S is approximately ten times than that of a sensor based on undoped CCTO film. The doped film sensor also showed stability and relatively short response and recovery times. Therefore, Ag-doped CCTO films with small doping concentration constitute an excellent candidate for developing H₂S sensors operating at low-temperatures.

Speaker: Mr Aukrit Natkaeo (Department of Physics, Faculty of Science, Chulalongkorn University)

89 Observation of Spin Seebeck Effect in Bulk Strontium Ferrite

ABSTRACT
Spin Seebeck effect (SSE) can be observed in magnetized ferromagnetic materials when subjected to a temperature gradient.In this work, the results on the SSE in the bulk strontium ferrite were demonstrated for the first time. The SSE measurement was developed in our lab and calibrated with a Y3Fe5O12 standard sample. The bulk strontium ferrite was characterized for the crystal structure and magnetic properties. It was then cut, ground and polished, before the Pt film was deposited on the surface. When subjected to the magnetic field and temperature gradient, the strontium ferrite showed the SSE signal which could be measured via the inversed spin Hall effect (ISHE). The SSE voltages measured across the Pt film showed the dependence on the magnetic field, the temperature gradient, and the Pt thickness, with the maximum signal of about 200 nV/K.

Speaker: Mr Champ Suksawat (Khon Kaen University)

90 One dimensional two-body collisions experiment based on LabVIEW interface with Arduino

The purpose of this work is to build a physics lab apparatus that is modern, low-cost and simple. In one dimensional two-body collisions experiment, we used the Arduino UNO R3 as a data acquisition system which was controlled by LabVIEW program. The photo gate sensors were designed using LED and LDR to measure position as a function of the time. Aluminum frame housewares and blower were used for the air track system. In both totally inelastic and elastic collision experiments, the results of momentum and energy conservation are in good agreement with the theoretical calculations.

Speakers: Parinya Saphet (CRRU), Dr Anusorn Tong-on (CRRU), Dr Meechai Thepnurat (Chiang Rai Rajabhat University)

91 One step hydrothermal synthesis of CNTs-NiS films for counter electrodes in dye-sensitized solar cells

Nickel sulfide (NiS) nanoparticles were grew on multiwall carbon nanotube (CNTs) and coated onto FTO-glass by the one step hydrothermal method at 160°C. These films were applied as counter electrodes (CE) for dye-sensitized solar cells (DSSCs). In the present work, electrocatalytic activity and electron-charge transfer resistance are investigated though cyclic voltammetry and electrochemical impedance spectroscopy measurements, respectively. Likewise, an effective surface area of counter electrode is presented and analyzed. Power conversion efficiency (PCE) enhancement of up to 24% (7.48% efficiency) from pure NiS (6.21% efficiency) is demonstrated for a CNTs-NiS DSSC.

Speaker: Dr Wasan Maiaugree (Khon Kaen University)

92 Optical and Structural Properties of Dye Sensitized Composite Semiconductor Photoanode

ZnS, a wide band gap semiconductor and good candidate for dye sensitized semiconductor solar cell (DSSC) photoanode was doped with aluminum. However, the role of ZnS and Al-doped ZnS in DSSC is lack of knowledge. Herein, we studied the effect of ZnS and Al-doped ZnS in TiO$_2 photoanode using a simplest preparation. The thin film was prepared by doctor blade technique using a mixture of TiO$_2 paste with ZnS and ZnS:Al. Structural property and the relevance of each elements in all anode thin films was characterized by means of X-ray diffraction. The Ru-based dye, N719 was used for semiconductor sensitization. The absorption and photoluminescence of TiO$_2 /N719 ,TiO$_2∶ZnS/N719 , TiO$_2∶ZnS:Al/N719 photoanodes were investigated. Then the role of ZnS and Al-doped ZnS in dye sensitized TiO$_2 photoanode is discussed.

Speaker: Ms Kamonchanok Wangcharoen (Division of Physics, Faculty of Science and Technology, Thammasat University, Klong Nueng, Klong Luang, Pathum-Thani, Thailand)

93 Optical properties of DC sputtered titanium dioxide/gold thin films

Titanium dioxide (TiO$_2$) thin films have been generally accepted as an important material in the fields of photocatalysis, photovoltaic and photochromic. The efficiency of TiO$_2$ films as an active layer in various applications strongly depends on their optical properties. In this present study, the optical properties of sputtered TiO$_2$ thin films were modified using nanoparticles gold (Au) underlayer. TiO$_2$ thin films with 100 nm thickness were prepared by DC magnetron sputtering on gold-coated glass substrate with the estimated thickness approximately 2, 6 and 10 nm. The deposited TiO$_2$/Au films were characterized using UV-Vis spectroscopy and photoluminescence (PL) spectroscopy. The transmittance of TiO$_2$/Au film in the visible region decreased from 87% to 50% when thickness of gold underlayer increased from 0 to about 10 nm. In addition, energy gap of TiO$_2$/Au film from Tauc’s plot decreased with the increase of the thickness of gold underlayer while the wavelengths of peak emission spectra obtained from PL were found to be increased. The modified optical properties indicated the probability of light absorption which leaded to the increase in electron-hole pair generation in this composite film.

Speaker: Mr Manas Sittishoktram (Department of Physic, Faculty of Science, King Mongkut’s University of Technology Thonburi)

94 Optical tristability Investigation in Two Coupled Ring Resonators

The microring resonators have potential applications for the photonic integrated circuits. The dynamical phenomena of the two coupled microrings require a simple and efficient numerical formalism for solution of the system. We present a simplified theory of the optical tristability inside the two coupled microrings that take into account Kerr nonlinearity and the effect of loss. We also compare the analytical results with the results from 3D finite-difference time-domain simulation. Besides, we show it is possible to obtain configurations which can tune the tristable region. This could be useful for designing optical logic applications.

Speaker: Dr Santhad Pithakwongsaporn

95 Optimization of Copper Surface as a Substrate for CVD growth of Graphene

Copper (Cu) foil substrate is the most widely used as a substrate for graphene growth by chemical vapor deposition (CVD). It is known that the suitable morphology and crystal orientation of Cu foil substrate, which are crystal plane of Cu (111), low roughness and large grain size, are required for the growth of good film uniformity of graphene. The purpose is to investigate the evolution of surface morphology and crystal orientation of Cu foil substrate, after various chemical treatment and annealing at high temperatures (800 – 1000$^o$C). Before a real growth of grapheme, we firstly focus on a preparation the Cu foil substrate by pretreatment in hydrochloric acid (HCl) and electro-polishing in phosphoric acid (H$_3$PO$_4$) in order to removing impurities on Cu foil surface. To increase the grain size of the (111) domains on the Cu foil substrate, after chemical cleaning process, the Cu foil substrates were annealed under nitrogen gas atmosphere. Scanning electron microscopy (SEM), optical microscopy (OM), atomic force microscopy (AFM) and x-ray diffraction spectroscopy (XRD) were utilized to investigate surface morphology and crystal orientation of the Cu foil substrate, that need to be optimized for the CVD growth of graphene. OM, SEM and AFM images illustrated an improvement surface of Cu foil substrates after pretreatment in HCl with the optimized concentration of 37% and etching time of 40 s. The conditions of electro-polishing was adjusted to be 50% H$_3$PO$_4$, voltage of 10 V, and polishing time of 60 s for achieving the smoothest Cu foil substrate surface. Furthermore, the strongest X-ray diffraction intensity ratio between the (111) reflection to other reflections, such as (200), (220) and (311) reflections, was observed for the Cu foil substrate annealed at 920 $^o$C and 2 mbar for 5 min. In addition, heat increasing rate, cooling rate and N$_2$ flow rate were 1 $^o$C /s, 5 $^o$C /s and 20 sccm, respectively. Graphene growth and its characterization results will discussed during presentation.

Speaker: Taworn Intaro

96 Performance of ZnO-doped recycled window glass as a thermoluminescence dosimeter

Thermoluminescence properties of Thai commercial window glass provided by Guardian Industries Corporation (denoted as WG) were studied. WG was doped with varying concentrations of ZnO The composition of glass is 90WG-10Na2O-xZnO (where x = 0.000, 0.001, 0.010, 0.100, 1.000 mol%). Glass samples were recycled by using melt quenching technique and cut into the dimensions of 6×6×1 mm3. After irradiated glass samples with X-ray at photon energy 160 keV in absorb dose rang 0-14 mGy, the glow curve structure, TL sensitivity, linearity and minimum detectable were investigated.

Speaker: Ms Thanaporn Thumsa-ard (Ubon Ratchathani University)

97 Permeation of Beta Cyclodextrin and its Derivatives into the Lipid Membrane

Beta cyclodextrin (βCD) and its derivatives such as methylated βCD (MEβCD) and hydroxypropyl βCD (HPβCD) have been widely used to improve the solubility and the stability of poor water soluble drugs. Most drugs are completely bound inside the hydrophobic cavity interior of the βCDs. In the present work, we studied the pre-step of drugs releasing based on drug-βCDs complexes. The interaction of three different types of βCDs i.e. βCD, 2,6-DMβCD and 2,6-HPβCD) with phospholipid bilayer was investigated using molecular dynamics (MD) simulations. The influence of chemical function groups and the orientation of βCDs interacting with bilayer surface on βCDs' permeation was studied. Our results showed that all βCDs passively adsorbed on the POPC bilayer surface via hydrogen bonding with different permeation depth and orientation. The order of permeation depth of βCDs was βCD > 2,6-DMβCD > 2,6-HPBCD. The βCD was permeated deeper when interacting with lipid bilayer by facing its secondary rim toward the bilayer's center. In contrary, the 2,6-DMβCD and 2,6-HPβCD adsorbed into the deeper part with turning its primary rim toward the bilayer's center. The molecular details of the interactions of βCDs and phospholipids are helpful to the selection of the appropriate βCDs in the pharmaceutical applications.

Speakers: Ms Wasinee Khuntawee (Department of Physics, Faculty of Science, Kasetsart University, Bangkok), Ms Pornkamon Nalakarn (Department of Physics, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand 
)

98 Preparation of aluminum doped zinc oxide thin films on glass substrate by sparking process and their optical and electrical properties

Aluminum doped Zinc Oxide (AZO) nanoparticle thin films were deposited on glass substrates by double tips sparking process which is a simple, low cost method and can be done at room temperature. The effect of Al doped ZnO was studied in order to improve electrical and optical transmittance properties. The doping ratios of Al into ZnO were controlled by different sparking power using different capacitor paralleled Al doping tips and were investigated by EDS. The surface morphologies and cross-section images were observed by scanning electron microscope (SEM). The thickness of the films was approximately 600-900 nm. The EDS results showed that Al content into ZnO increased when the capacitance paralleled Al tips increasing. The Al doping ratios were 3, 5, 7, 13 and 22 at.% when capacitances paralleled Zn : Al tips were 40:0.5, 40:1.1, 40:1.5, 40:3.1 and 40:4.7 nF, respectively. SEM images indicated agglomerated particle size increased after annealing treatment. The crystalline structure was characterized by X-ray diffraction and Raman spectroscopy. UV-Vis spectroscopy was used to measure the optical properties. The optical transmittance spectra of the AZO thin film exhibited greater than 50 % in the visible region. Also, their electrical properties were measured by Van Der Pauw technique for transparent conducting oxide glass application.

Speaker: Mr Anupong Sukee

99 Preparation of strontium- and/or zinc-doped hydroxyapatite nanoparticles and their polycaprolactone composite fibrous scaffolds

In this work, hydroxyapatite (HA) and hydroxyapatite doped with Sr (HA-Sr), Zn (HA-Zn) and both Sr-Zn (HA-SrZn) were synthesized by a sol-gel method and combined with polycaprolactone (PCL) to make HA/PCL composites using an electrospinning technique. The synthesized nanoparticles and their composite fibers were investigated using various techniques. The X-Ray Diffraction (XRD) result showed the characteristic peaks of the hydroxyapatite structure; whereas the scanning electron microscopy (SEM) and transmission electron microscopy (TEM) results revealed that the synthesized nanoparticles were successfully incorporated into the randomly interconnected and highly porous PCL matrix.

Speaker: Mr Teeranat Pantasri (Materials Science and Nanotechnology Program, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand)

100 Quantum reflection in the linearly downward potential

In this work, the motion of a particle in one dimension, under the influence of the potential well that is modeled as the linear downward of length $L$ with a finite depth $|V_{0}|,$ is studied within the context of the non-relativistic quantum mechanics. The attention is paid on the paradoxical phenomenon of the reflection of a particle that is in contrast between classical and quantum physics. Classically, the reflection effect occurs only at a potential
barrier. To demonstrate such counterintuitive phenomenon, the Schr$\ddot{\rm{o}}$dinger equation is solved to obtain the reflection coefficient in the scattering state by considering an incident particle with an energy $E>0,$ that is represented by a monochromatic plane wave, propagates freely from left to right, pass through the potential well. The continuity conditions at boundaries give the desired result that is expressed in terms of the Airy functions which
depends on the incident energy $E,$ the strength $|V_{0}|$ and the range $L$ of the well. The value of the reflection coefficient $R$ lies in the interval $0\leq R<1,$ and its behavior is the decreasing function with respect to the range $L.$

Speakers: Mr Noppasin Chamnan (Burapha University), Dr Boonlit Krunavakarn (Burapha Univesity)

101 Selected Screen for Engaging Students in Projectile Motion

Connecting physics concepts with that interest activities or with activities that interest. Thought will allow students strong to build a foundation. When an event of interest to the students, it will contribute to the students' responses, engaged and enthusiasm for learning. Learning activities resulting from things that interest and have found on a regular basis can have a lasting and memorable. Both can help enhance the learning experiences of students. One such activity that can be described in this paper, the learning activity through a film as an application of basic projectile motion. So that students understand the nature of the motions. There is also aimed to develop critical thinking skills of the students.

Speaker: Mr Ar-si Dramae (Department of Physics Faculty of Science , Ubon Ratchathani University)

102 Selective area growth behavior of ZnO nanorod arrays in hydrothermal synthesis

ZnO nanorod arrays have become to attract much attention because the uniform and symmetry of ZnO nanorods can provide great optical and electrical potential in many nanodevices. Here, we have controlled nucleation sites using electron beam lithography technique and grown ZnO nanorods via hydrothermal synthesis to observe growth behaviors. We have measured diameter of nanorods and density of each aperture area. The results presented that the aperture size and distance between adjacent apertures strongly affected the growth of ZnO nanorods such as nucleation layer and growth rate. There is no nanorod grown on the aperture area when aperture size is large and distance between apertures is small. On the other hand, there are several nanorods grown through large aperture size with large distance between apertures. These phenomena show the growth behavior of ZnO nanorods corresponding to the different aperture sizes and distances. This is very useful to enhance the properties of ZnO nanorods and also can achieve high performance of nanodevices.

Speaker: Nantarat Srisuai

103 Simple Harmonics Motion experiment based on LabVIEW interface with Arduino

In this work, we developed an innovative physics lab apparatus that is modern, cheap and simple. The ultrasonic sensor was used to measure the position of a mass attached on a spring as a function of time. The data acquisition system and control device were developed based on LabVIEW interface with Arduino. The experimental was designed to explain the simple harmonics motion similar to the wave propagation. The simple harmonic system (mass and spring) was observed and the motion can be realized using curve fitting to the wave equation in Mathematica. We found that the spring constants provided by Hook’s law and the wave equation fitting are in good agreement.

Speakers: Dr Anusorn Tong-on (Chiang Rai Rajabhat University), Parinya Saphet (CRRU), Dr Meechai Thepnurat (Chiang Rai Rajabhat University)

104 Simulations of induced transmembrane potentials of tilapia’s egg using Hen egg RC-model

The present study proposes another alternative approach to model the geometry of Nile tilapia egg for evaluation of the induced transmembrane potential. The actual shape of tilapia egg is an asymmetrical prolate spheroid with a short prolate spheroid bottom and a more elongate prolate spheroid at the top with a common equator rather than a symmetrical prolate spheroid. Unfortunately, the precise model of such non-spherical bioparticle does not exist as yet. In the past, the closest available model was as a shelled symmetrical prolate-spheroid which gave the large error to calculate transmembrane potential. This work proposes the complete “hen egg RC-model” to analyze the implicit value of electrical breakdown transmembrane potential. The two semi-minor axes are set to equal one another. The ratio between the semi-major and semi-minor axes is 1.0-1.5. We keep the volume of the egg constant throughout our analysis which is equivalent to that of the “hen-egg model” possessing the effective values of the semi-major and the semi-minor axes so that the polarization of the egg can be assumed to be the same over the whole egg volume. In the case of the egg possessing a single dielectric shell, it was also analyzed as the equivalent tri-phases of RC-circuit using three pairs of resistors and capacitors to represent the conductive and capacitive properties of the egg’s shell, the inner part of the egg and the suspending medium, respectively. The complex specific impedances of each compartment and induced transmembrane potentials of tilapia’s egg were finally analyzed.

Speaker: Prof. Dr.Sakshin Bunthawin (Biotechnology of Electromechanics Research Unit, Science of Physics, Faculty of Technology and Environment, Prince of Songkla University, Phuket Campus )

105 Single-mirror, off-axis schlieren system’s sensitivity determination

Schlieren photography is a technique used to visualize density gradient of fluid medium, which is due to a linear relationship between fluid density and refractive indices. In this study, a single mirror off-axis schlieren system was employed to observe minimum temperature difference between room and heated object, vacuum flask.The tracker program was used in measuring relative light intensities. It was found that the minimum difference temperature observed was 0.9 $^o$C.The theoretical minimum air density gradient is 0.128 kg/m$^4$, while the observed one is 2.98 kg/m$^4$. When using fluid dynamics computer simulation, the location where the light intensity data was acquired, the air density gradient was 0.0682 kg/m$^4$.

Speaker: Mr Kittisak Ketaiam (Yupparaj Wittayalai School)

106 Stability and Electronic property of Vacancy Defects in Silicon Carbide Nanosheet based on DFTB

Silicon Carbide (SiC) is the chemical compound of carbon and silicon. Recognized as a perfect semiconductor with superior characteristics, SiC is widely used in high-temperature, high-power, and high-frequency electronic applications. Defects in a semiconductor have become a primary important issue since they can damage and change the unwanted electrical properties. The study of geometric and electronic properties of the defects in SiC nanosheet is crucial to understand the effects on an electronic device. In this research, we present a study of the energy gap and formation energy of the defective SiC nanosheet (Si$_1$$_4$$_4$C$_1$$_4$$_4$) based on self – consistent charge density functional based tight binding (SCC- DFTB) method including van der Waals dispersion corrections. The geometric and electronic properties of defective SiC nanosheet related to the number of vacancy defects in SiC nanosheet have been studied systematically. The defective SiC nanosheet was made by removing Si atoms and C atoms around the central region of SiC nanosheet. The energy gap of pristine SiC nanosheet exhibited 1.060 eV. The energy gap of defect SiC nanosheets were in range of 0.049 to 0.811 eV when Si atoms were removed more than C atoms and 0.028 to 0.753 eV in case of the same rate of removal Si atoms and C atoms. However, when Si atoms were removed less than C atoms, the energy gap showed the less of 0.005 to 0.482 eV. The stability of the SiC nanosheet was investigated by using the calculated normalized formation energies. By increasing vacancy atoms, the defect stability has produced an identical result which is a decline from 75.321 to 87.453 eV. On the other hand, the defect stability has increased (67.722 to 75.504 eV) when vacancy atoms are added to the SiC nanosheet by removing Si atoms less than C atoms. The highest formation energy (87.453 eV) has been found after one single C atom vacancy defect was withdrawn from SiC nanosheet (Si$_1$$_4$$_4$C$_1$$_4$$_3$) while the lowest formation energy was 67.722 eV when one Si atom was removed (Si$_1$$_4$$_3$C$_1$$_4$$_4$). We have found that the ratio between the number of silicon atoms and the number of carbon atoms is of the great importance to the stability and electronic properties of the vacancy defect in SiC nanosheet.

Speaker: Ms Onsuda Arayawut (Department of Physics, Faculty of Science, Kasetsart University, Thailand)

107 Stoichiometry and Performance in PCDTBT:Perylene Solar Cells

Stoichiometry and Performance in PCDTBT:Perylene Solar Cells

Wannakan Sathongsang1, Kanyaporn Thubthong1, Pisist Kumnorkaew2, Vinich Promarak3,
and Yingyot Infahsaeng1*
1Division of Physics, Faculty of Science and Technology, Thammasat University, Klong Nueng, Klong Luang Pathum-Thani, Thailand
2National Nanotechnology Center (NANOTEC), National Science and Technology Development Agency (NSTDA), Pathumthani, Thailand
3Vidyasirimedhi Institute of Science and Technology, School of Molecular Science and Energy, Wangchan, Rayong, Thailand

*E-mail: yingyot.infahsaeng@gmail.com

Abstract
The bulk heterojunction solar cell has been developed for many decades. The electron acceptor is one of the key performance in this solar cells, typically using fullerene derivatives. However, the free fullerene solar cell has been proposed using difference acceptor molecule. Herein, the morphology in bulk heterojunction PCDTBT:Perylene thin films of varied stoichiometry (1:1, 1:2 and 1:4 PCDTBT:Perylene) and PCDTBT:PC70BM thin films is investigated and compared using Atomic Force Microscopy (AFM). PC70BM and a novel Perylene are electron acceptor and transporting molecules in polymer based solar cells. This Perylene derivative have been firstly used as electron acceptor in solar cells. The optical and energetic properties of perylene suggest that this molecule may be a good candidate for electron acceptor. The solar cell performance of varied electron acceptor and stoichiometry is reported and correlated with the morphology of thin films.

Keywords: polymer solar cells, perylene, stoichiometry, bulk heterojunction

Speaker: Ms Sathongsang Wannakan

108 Stoichiometry and Performance in PCDTBT:Perylene Solar Cells

The bulk heterojunction solar cell has been developed for many decades. The electron acceptor is one of the key performance in this solar cells, typically using fullerene derivatives. However, the free fullerene solar cell has been proposed using difference acceptor molecule. Herein, the morphology in bulk heterojunction PCDTBT:Perylene thin films of varied stoichiometry (1:1, 1:2 and 1:4 PCDTBT:Perylene) and PCDTBT:PC70BM thin films is investigated and compared using Atomic Force Microscopy (AFM). PC70BM and a novel Perylene are electron acceptor and transporting molecules in polymer based solar cells. This Perylene derivative have been firstly used as electron acceptor in solar cells. The optical and energetic properties of perylene suggest that this molecule may be a good candidate for electron acceptor. The solar cell performance of varied electron acceptor and stoichiometry is reported and correlated with the morphology of thin films.

Speakers: Ms Wannakan Sathongsang (Division of Physics, Faculty of Science and Technology, Thammasat University, Klong Nueng, Klong Luang Pathum-Thani, Thailand), Ms Kanyaporn Thubthong (Division of Physics, Faculty of Science and Technology, Thammasat University, Klong Nueng, Klong Luang Pathum-Thani, Thailand)

109 Stretchable strain sensor based on metal nanoparticles-Polydimethylsiloxane nanocomposites

The preparation of nanocomposites materials by using Polydimethylsiloxane (PDMS) with metal nanoparticles (gold and silver) and metal oxide nanoparticles (Zinc oxide and Titanium dioxide). Then, Characterization of the films was carried out by atomic force microscope (AFM) and fourier transform infrared spectroscopy (FTIR) after that the film creates to the electrodes on the film for applying an strain measurement devices. The maximum current output increased as a result of the metal nanoparticle that composites with an improved electrical conductivity of PDMS strain sensor.

Speaker: Dr Thutiyaporn Thiwawong (College of Nanotechnology)

110 Study Motion of PVC-Cylindrical on Incline Plane using g-Sensor Compare with Motion Simulate

The g-sensor with a wireless, using to study motion of hollow PVC-cylindrical on incline plane.This sensor will packed inside PVC-cylindrical. For experimental,We drop the PVC-cylindrical on the top of incline plane length 1.2 m.By changed high of plane at 3.5, 4.5, 5, 5.5, 6 and 6.5 cm relate to angle 0.0318, 0.0409, 0.0454, 0.0499, 0.0545 and 0.0590 rad respectively. The signal from the sensor will send pass wireless to computer and show in hyper-terminal. The data will be compare with simulate signal to determine speed and angular speed various with time.For result data at high 3.5, 4.5, 5, 5.5, 6 and 6.5 cm compare with simulate data motion has error are 3.12%, 3.89%, 4.71%, 6.28%, 9.36% and 18.20% respective. From experiment, we can find limit of this sensor for this experiment at high 8 cm.Because clock frequency limit of sensor.

Speaker: Mr Dusit Ngamrungroj (KMUTNB)

111 Study of formaldehyde molecule adsorption on pristine, defect and functionalized carbon nanotubes by self-consistent charge density functional tight-binding method

We aim to fabricate formaldehyde gas sensors for identifying formalin contamination of fresh raw food materials, especially seafood. Carbon nanotubes (CNTs) are one of materials widely used for fabrication of gas sensors because of their unique electronic properties. Unfortunately, pristine CNTs exhibit very low sensitivity for formaldehyde molecule adsorption. In this research, we have used self-consistent charge density functional tight-binding (SCC-DFTB) method to model the various CNTs including pristine, defect and N2 functionalization for finding the best structure for formaldehyde sensing. Pristine CNTs (9,0) containing 180 carbon atoms were built and their two ends were capped with hydrogen atoms to avoid the boundary effects. Then, the CNTs were made a vacancy defect and functionalized by N2 molecules. Interaction between a CNTs surface and formaldehyde molecule was investigated. Total energy of interaction was calculated. The primary results showed the total energy of pristine, defected and N2 functionalized CNTs was 0.13, 0.14 and 0.21 eV, respectively. The functionalization on CNT surfaces with N2 molecules improved a better interaction between formaldehyde molecules and CNTs.

Speaker: Mr Kriengkri Timsorn (Department of Physics, Faculty of Science, Kasetsart University, Chatuchak Bangkok, 10900, Thailand)

112 Study of the efficiency calibrations of HPGe detector for the PGNAA system

One of the most important part of the Prompt Gamma Neutron Activation Analysis system (PGNAA) is the High Purity Germanium detector (HPGe). In this paper, the calibrations of an HPGe detector were made with the isotopic source $^{152}$Eu. The same detector was modelled in the MCNP5 and simulated. The thickness of the dead layer was determined. The simulated and experimental efficiency over the energy range of the $^{152}$Eu are compared observing a satisfactory agreement.

Speaker: Mr Wichian Ratanatongchai (Thailand Institute of Nuclear Technology (Public Organization))

113 Study of tilapia’s egg permeabilization with the optimized electrical parameters

On the basis of electrical induction of eggs for sex reversal, the egg membrane exposed to a very short high-intensity electric field pulses can be temporarily permeable in specific regions of the egg. During the destabilization period, the membrane is highly permeable to exogeneous molecules present in the surrounding medium. Optimization of protocols has led to a situation where high egg viability can be combined with high percentages of egg permeabilization and hormone transfection. The present study achieved to have over 90% of eggs permeabilized with less than 5% egg death. Conditions traditionally used to achieve this are 1-5 square pulses of 50-1,000 micro-second duration using electric field strengths 0.25-87.50 kV/m. Some issues that might be concerned when performing in vitro electroporation were taken into account. Optimization for each egg clutch is necessary. A good result increases with homogeneity in egg size and conversely that for egg with very large variations in egg size. Eggs size of the semi-major axis of 1.5 mm and semi-minor axis 1.0 mm were selected for electrical inductions throughout this work.

Speaker: Prof. Dr.Sakshin Bunthawin (Biotechnology of Electromechanics Research Unit, Science of Physics, Faculty of Technology and Environment, Prince of Songkla University, Phuket Campus )

114 Study on Inverse Laplace Transform of NMR relaxation signal of Sticky rice.

In this study, the composition of sticky rice was studied using NMR relaxometry. Because the rice seeds have several elements, the NMR signal is multiexponential decay. However, its components that yield NMR signals can be separated by using Inverse Laplace Transform method. This method is data analyze by from least squares algorithms. The Downhill Simplex method was used to find the variable values faster. Numerical results of signals analysis are comprised of discrete spectrum of T$_1$ and T$_2$. These spectrums of sticky rice samples are shown separation of the peak composition. In this work the resulting spectrum has two peaks, each peak has a value of T$_2$ is 0.31 and 1.29 ms, respectively.

Speaker: Mr Nattawoot Maleelai (Khon Kaen University)

115 Surface study of irradiated sapphires using AFM

The irradiation is one of the gemstone enhancements for improving the gem quality. Typically, there are many varieties of irradiated gemstones in the gem market such as diamond, topaz, and sapphire. However, it is hard to identify the gemstones before and after irradiation. The aim of this study is to analyze the surface morphology for classifying the pre- and post- irradiated sapphires using atomic force microscope (AFM). In this study, the sapphire samples were collected from Thailand and Sri Lanka based on their different geological origins. The samples were irradiated by high energy electron beam for a dose of ionizing radiation at 40,000 kGy. As the results, the surface morphologies of unirradiated sapphires show regular atomic arrangement, whereas, those of irradiated sapphires show the nano-channel observed by the 2D and 3D AFM images. The atomic step height and root mean square roughness have changed after irradiation due to the micro-structural defect on the sapphire surface. Therefore, this study is the frontier application for sapphire identification before and after irradiation.

Speaker: Natthapong Monarumit

116 SYNTHESIS OF CaCu$_3$Ti$_4$O$_1$$_2$ BY MODIFIED SOL-GEL METHOD WITH HYDROTHERMAL

CaCu$_3$Ti$_4$O$_1$$_2$ powders were synthesized by modified Sol-gel method with Hydrothermal using Ca(NO$_3$)$_2$• 4H$_2$O, Cu(NO$_3$)$_2$• 3H$_2$O, Ti(OC$_3$H$_7$)$_4$ and freshly extracted egg white (ovalbumin) in aqueous medium. The precursor was calcined at 800, 900 and 1000 °C in air for 8 h to obtain nanocrystalline powders of CaCu$_3$Ti$_4$O$_1$$_2$. The calcined CaCu$_3$Ti$_4$O$_1$$_2$ powders were characterized by XRD, TEM, and EDX. The XRD results indicated that all calcined samples have a typical perovskite CaCu$_3$Ti$_4$O$_1$$_2$ structure and a small amount of CaTiO$_3$, CuO and TiO$_2$. TEM micrographs showed particle size 100 – 500 nm and EDX results showed elements of CaCu$_3$Ti$_4$O$_1$$_2$ powders have calcium, copper, titanium and oxygen.

Speaker: Dr Chivalrat Masingboon

117 The determination of the energy values and the composition analysis of M-16 rifle black powders

The determination of the energy values, specifically the heat of combustion of various M-16 black powders werethe important part of the bulletefficiency investigations. The calorimetric bomb is commonly used for these determinations. Four M-16 black powders from the differences sources were used as samples for this research. It was found that,after using calorimetric bomb technique, the gross heating value in Joules/g of sample 1-4 were 10,647, 10,416, 5,281 and 3,878 respectively. The CHNS chemical composition have also been studied. The result found that, Carbon and Nitrogen compositions of sample 1 shown the highest values and provided a few differences with sample 2 while sample 3 and 4 shown lowest Carbon and Nitrogen percentages composition. The hydrogen composition of all samples were equally values, however only sample 3 and 4 displayed Sulfur values while none Sulfur values of sample 1 and 2. Since M-16 black powders consist of the chemical part that provided energy, particularly the Carbon, Hydrogen and Nitrogen, it would be possible to comparison the energy values of various M-16 black powder samples by estimating the C and N of CHNS analysis results in the sample.

Speaker: Ms Rewattee Satee

118 The effects of Fe-doping concentration in Ba$_{(1-x)}$Fe$_{x}$TiO$_{3}$ thin films on their microstructure and magnetic properties

The effects of Fe-doping concentration in Ba$_{(1-x)}$Fe$_{x}$TiO$_{3}$ (x=0, 0.02, 0.04, 0.06 and 0.08) thin films prepared by a sol-gel method on their microstructure and magnetic properties were systematically studied. From X-ray diffraction measurements, the full width at half maximum (FWHM) of peaks were increased as the doping concentration increased. The thickness of the films measured from FESEM micrographs was about 400 nm and the grain size decreased with increasing in the Fe-doping concentration. The EDX analysis approach shows that Fe ions are substituted into Ba sites. The oxidation state of Fe in Ba$_{(1-x)}$Fe$_{x}$TiO$_{3}$ films was examined by X-ray absorption spectroscopy near the edge structure (XANES) using a synchrotron source. The ferromagnetism was observed in undoped BaTiO$_{3}$ and
Ba$_{(1-x)}$Fe$_{x}$TiO$_{3}$ films and found to be dependent upon Fe-doping concentration. The saturation magnetization is enhanced to a maximum value of 5.13x10$^5$ emu/m$^3$ at x=0.02.

Speaker: Mr Witheetat Amatyakul (Department of Physics, Faculty of Science, Chulalongkorn University 254 Phyathai Road, Patumwan, Bangkok Thailand. 10330)

119 The evaluation of laser cleaning of silica nanowires

The aim of this work is to investigate the laser cleaning of contaminants from surfaces of silica nanowires. Experimental parameters affected particle removal were explored using pulsed Nd:YAG laser radiation at a wavelength of 1064 nm. The laser beam was focused and scanned across the surfaces of the nanowires. The interaction between laser radiation and a certain thickness in the contaminant layers was analyzed. The results suggest that low laser fluences allow greater control over the removal depth reducing the risk of damage. The cleaning efficiency was determined. The laser cleaning technique can open up completely challenges in applications of nanophotonics.

Speaker: Chonticha Chunhakit

120 The investigation of high school student's energy concept by using analogies

Alternative energy tends to be more widespread in Thailand because the advanced technologies enhance the potential of equipment which becomes more economically rather than setting in laboratory likes in the past. For this reason students should understand profoundly about the characteristic of energy before they learn about alternative energy. To help students get more comprehension about the characteristic of energy, we need to investigate the idea about energy. There are two main reasons for the investigation (1) to identify the misconception about energy (2) to find out the most frequent analogies that are used by students. Students were given a task to write their analogies after doing the activity (STEM) about energy in class. The answers were categorized into four terms of scientific context: energy can be accounted, can change forms, can be lost and can be transferred. In general answers can be analyzed in more than four or five terms which depend on the scientific content.

Speaker: Mr Khanti Toedtanya (Ubon Ratchatani University)

121 The Measurement of Thermal Diffusivity in Conductor and Insulator by Photodeflection Technique

The purpose of this study is to compare and estimate thermal diffusivities of conductor and insulator material by using photothermal deflection which varies frequency. The experimental setup consists of 2 laser lines: 1) a pump laser beams through a modulator, varied frequency, controlled by lock-in amplifier then focused beam at sample surface by lens. 2) a probe laser which is perpendicular with the pump laser beam skims the sample surface. The probe laser deflection signal is obtained by a position sensor controlled by lock-in amplifier. Thermal diffusivity is calculated by measuring the amplitude and phase of the Photodeflection signal and compared with the thermal diffusivity of standard value. The results of thermal diffusivities, calculated by amplitude and phase, are slightly different from the standard value.

Speaker: Uthed Achathongsuk

122 The pre-service teachers understanding about moon phase.

Interactions in the Sun-Earth-Moon System are common misconception. Pre-service teacher should be developed in the Sun-Earth-Moon system to prepare for professional experience in school. So in this work revisit understanding of pre-service teacher in the Sun-Earth-Moon system, this emphasize moon phase concept compose of observe moon phase (shape) and position of the moon in the orbit about the earth respect to the sun. This research instrument is open ended question. Their responses were interpret and categorized into level of understanding and considerate key-word; the earth, the moon and the sun. The results found from this studied bring to pre-service teacher to design lesson plan and tools for improve concept about the moon phase.

Speaker: Nudchanard Saenpuk

123 The sound education by applying mathematica program.

This study was to develop instruction media title the sound education by applying mathematica program. The objective of study are as follows compare achievement before and after learning of students received from activities of learning by instruction media title the sound education by applying mathematica program and study satisfaction of student to organize learning activities by instruction media title the sound education by applying mathematica program. The sample is student class m.4/3 Triamudomuksanomklao Nakornratchasima school , second semester , academic year 2016 , total 33 people. Get by purposive sampling. The instrument used in the study include instruction media title the sound education by applying mathematica program , learning management plan , achievement test and satisfaction questionnaire. The statistics used to analyze data include the percentage , standard deviation and compare achievement before and after learning by t-test. The study we find that the achievement after learning activities by instruction media title the sound education by applying mathematica program higher than the achievement before learning activities by instruction media title the sound education by applying mathematica program on statistical significance at .05. The study satisfaction of student to organize learning activities by instruction media title the sound education by applying mathematica program is most level.

Speaker: Mr Thanapon Premkamon

124 Torque Induced on Lipid Microtubules with Optical Tweezers

Chiral Phospholipids are found self-assembled into cylindrical tubules of 500 nm in diameter by helical winding of bilayer stripes under cooling in ethanol and water solution. Theoretical prediction and experimental evidence reported so far confirmed the modulated tilt direction in a helical striped pattern of the tubules. This molecular orientation morphology results in optically birefringent tubules. We investigate an individual lipid microtubule under a single optical trap of 532 nm linearly polarized laser. Spontaneous rotation of a lipid tubule induced by radiation torque was observed with only one sense of rotation caused by chirality of a lipid tubule. Rotation discontinued once the high refractive index axis of a lipid tubule aligned with a polarization axis of the laser. We further explored a lipid tubule under circularly polarized optical trap. It was found that a lipid tubule was continuously rotated confirming the tubule birefringent property. We modified the shape of optical trap by cylindrical lens obtaining an elliptical profile optical trap. A lipid tubule can be aligned along the elongated length of optical trap. We reported an investigation of competition between polarized light torque on a birefringent lipid tubule versus torque from intensity gradient of an elongated optical trap

Speaker: Dr Nattaporn Chattham

125 Tuning of Preparational Factors Affecting the Morphological Structure and Gas Separation Property of Asymmetric Polysulfone Membranes

Abstract: The aim of this work was to study the effect of preparational factors such as solvent type, polymer concentration, evaporation time (ET) and non-solvent additive, on the morphological structure, physical and gas separation properties of the prepared membrane samples by tuning of these parameters. Flat sheet asymmetric polysulfone (PSF) membranes were prepared by the dry/wet phase inversion process incorporated with the double coagulation bath method. The alteration of the prepared membranes were analyzed through the several scientific techniques such as; contact angle, Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and Dynamic Mechanical Thermal Analysis (DMTA). Furthermore, gas separation performance of membrane samples was measured in term of gas permeation and ideal selectivity of CO2/CH4. The results showed that the change of preparational factors can affect to the gas permeation of asymmetric PSF membranes. For example, the selective layer thickness increased with increasing of ET and polymer concentration. This lead to increase significantly of ideal selectivity of CO2/CH4. The CO2/CH4 ideal selectivity was also increased with increase of non-solvent additive concentration in casting solution. In summary, the tuning of preparational factors affected to morphological structure and physical and gas separation properties of PSF membranes.

Speaker: Dr Chalad Yuenyao (Department of Physics Faculty of Science and Technology, Phetchabun Rajabhat University, Sadiang-subdistrict, Muang, Phetchabun 67000, Thailand)

126 Vacuum Vaporization Technique for Latent Fingerprints Development on Thermal Papers using Lawsone Natural Products

The vacuum vaporization is a technique of thin-film deposition. This process is widely used in the semiconductor, microelectronic and optical industries which involved the deposition thin film of metals onto surfaces. The metals used was generated into their gas phases and deposited to substrate for a thin film. Currently, this technique is used to develop of visualized latent fingerprints on banknotes for forensics investigation using vacuum metal deposition of copper and gold. However, in this study, we reported the first utilization of lawsone instead of metals in the vacuum vaporization technique. The lawsone was sublimation in vacuum and showed the detected latent fingerprints on thermal papers.
The method involves hanging the thermal paper samples 5, 10, 15 cm above a heating source with dispersed lawsone solids in a vacuum chamber. The optimized condition for lawsone sublimation are 50, 100, 150 mg with low-vacuum (0.1 mbar) and vaporizing temperature at 40-60°C. The sample fingerprints was left for 1, 3 and 7 days before examination comparison between lawsone and fingerprint ink pad using an Automated Fingerprint Identification (AFIS).
The resulted showed that using 50 mg lawsone sublimation on thermal paper at the range of 10 cm evidenced the clear, detectable minutiae which can be used for visualization and identification of latent prints without the background black staining known. Thus, This study might be interested application for developing latent fingerprints as a solvent free technique and non-hazardous materials.

Speaker: Mr Noparat Phungyimnoi

127 Verification of electrical inductions of O.niloticus egg with physiological membrane pores

The analysis of electrical inductions of O.niloticus egg’s membrane is based on the transmembrane potential, induced due to applied electric field. The implication of the analytical model has been interpreted in terms of understanding the influence of egg size, pulse duration and electro-physical conditions of eggs on the E-field parameters (strength and duration) required for electroporation. Increasing electric field strengths resulted in increased values of the induced transmembrane potential reaching to the limit of critical values. For the controlled egg (no-induction), pore densities and pore sizes appearing on the shell surface were revealed and observations were carried out through SEM micrographs. The local pores were randomly distributed over the surface. They were volcano-shape pores. For the induced experiments, several deep and sharp pores and some partially open can easily be observed in the E-face following the application of pulse of 87.50 kV/m electric field strength, 50 µs pulse-duration and single-square wave pulses. Pore densities of both cases of the controlled and induced eggs were equal. In the case of five-square wave pulses, it was very interesting that the pore diameter of the induced eggs was larger than that of the control; where electroporation of Nile tilapia eggs clearly occurred. Pore densities of the both cases for the controlled and electroporated eggs had no different.

Speaker: Prof. Dr.Sakshin Bunthawin (Biotechnology of Electromechanics Research Unit, Science of Physics, Faculty of Technology and Environment, Prince of Songkla University, Phuket Campus )

128 Viability determinations of yeast cells using translational dielectrophoretic speeds

Living yeast cells in the brewery industry are active cells. They have different responses to AC electric field if they possess different dielectric properties. Electrical parameters which are used to determine health of yeast cells are the conductivities of the cytoplasm (CC), the cell membrane (MC), dielectric constant of the membrane and the cytoplasm, respectively. These parameters affect cell translational speeds of positive dielectrophoresis. We measured yeast velocities during their movement towards the electrode tips, under various AC field frequencies. The value of LCF, where yeast cells were repelled (i.e. negative force) from the tip after being attracted, was recorded against the conductivity of the solution (SC). It was observed that as the SC was increased the LCF was shifted towards a higher frequency value. Yeast velocity spectra were reduced significantly under greater SC value. When the increased SC reached a critical value the attractive force became negligible, implying equivalence to the cytoplasmic conductivity. Our experiments showed that yeast cells of 1.15 x 10$^5$ cell/ml displayed the initial positive dielectrophoresis at LCF of 60-90 kHz, when using SC of 6 microS/m. The velocity spectrum of yeast suspensions were affected by SC of which the cells were suspending during the experimentation. An abrupt change in the velocity pattern was explained in terms of the dielectric properties of cell membrane and cytoplasm of yeast cells which reflect their metabolic health status. By iterative curve-fitting methods, we achieved to determine the health of yeast suspensions expressed in terms of the cytoplasmic and the membrane conductivity values.

Speaker: Prof. Sakshin Bunthawin (Biotechnology of Electromechanics Research Unit, Science of Physics, Faculty of Technology and Environment, Prince of Songkla University, Phuket 83120, Thailand)

129 Yttrium doped TiO$_2$ nanotubes prepared by anodization method

In this paper, we aim to characterize the microstructure of Yttrium doped TiO$_2$ nanotubes. These were successfully synthesized by anodization method on Ti sheets. The electrolyte was composed of ethylene glycol (EG), ammonium fluoride (0.3 % wt NH$_4$F) and deionized water (2% vol H$_2$O) with different concentrations of dopant Y$_2$O$_3$. A constant DC power supply of 50 V was used during anodization with anodizing times of 2 hours. The samples were investigated using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The structural and morphological studies showed that TiO$_2$ nanotube arrays were highly ordered and the Yttrium ion dopant may be incorporated into interstitial positions of the TiO$_2$ sheets.

Speaker: Ms Watchareeya Chaiyarat (Ubonratchathani University)

Poster Presentation I

Poster Presentation I

A3: Optics and Photonics

Conveners: Prof. Nattaporn Chattham, Prof. Apichart Pattanaporkrattana

130 Digital holographic 3D imaging spectrometry (a review)

This paper reviews recent progress in the digital holographic 3D imaging spectrometry. The principle of this method is a marriage of incoherent holography and Fourier transform spectroscopy. Review includes principle, procedure of signal processing and experimental results to obtain a multispectral set of 3D images for spatially incoherent, polychromatic objects.

Speaker: Prof. Kyu Yoshimori (Faculty of Science and Engineering, Iwate University, 4-3-5 Ueda Morioka, Iwate 0208551 Japan)

131 Deterministic cavity quantum dot coupling and fabrication of an ultrabright source of entangled photon pairs

Quantum dots present discreet quantum states and appear as artificial atoms in the solid state. Like an atom, a quantum dot can emit single photons, or polarization entangled photon pairs. Numerous potential applications rely on the control of the spontaneous emission of single quantum dots embedded in optical microcavities. For example, the regime of spontaneous emission enhancement (Purcell effect) allows efficient extraction of single photons emitted by the dot and to fabricate very bright sources for the field of quantum information. The strong coupling regime between the quantum dot and a cavity mode gives rise to mixed states of light and matter which can be used to entangle distant qubits. However, the actual coupling of a cavity mode and quantum dot is a significant challenge because the standard growth techniques of these emitters do not allow to control in a deterministic way their spatial and spectral characteristics.

The first result I will present is a technique which allows for the deterministic coupling of a single quantum dot to a cavity mode. This technique has been used to demonstrate the control of spontaneous emission in the weak coupling regime as well as in the strong coupling regime.

The second result pertains to the design, fabrication and characterization of an original microcavity which allows for the efficient extraction of polarization entangled photon pairs. By deterministically coupling a quantum dot to the modes of a photonic molecule, we have fabricated a source of polarization entangled photon pairs one order of magnitude brighter than any other existing source.

Speaker: Dr Adrien Dousse

132 Design of a solar-pumped frequency-doubled 532 nm Nd:YVO4 laser

This study has focused the design, development and demonstration of a frequency-doubled 532 nm Nd:YVO4 laser pumped by solar light. The solar pumped laser is consisted of the optically contracted Nd:YVO4 crystal and KTP crystal with a system of laser mirrors deposited onto crystal sides. The design is aimed to achieve the laser emission using the direct end-pumping approach. In addition, the solar tracking system is developed to orient the sunlight collecting system toward the sun. The measurement of the power distribution along the laser crystal is discussed. Furthermore, a novel design of an optical filter is proposed to diminish the heat load into the laser crystal. This solar pumped laser system is appealing for a variety applications including laser communication, imaging and defense applications.

Keywords: Lasers , Solar pumped laser, Optically pumped lasers

Speaker: Mr Phumipat Kittiboonanan

133 Silicon nitride waveguide-integrated Ge/SiGe quantum wells optical modulator

Silicon-based photonics has generated a strong interest in recent years, mainly for optical telecommunications and optical interconnects in integrated circuits. The main rationales of silicon photonics are the reduction of photonic system costs and the increase of the number of functionalities on the same chip combining photonics and electronics. Waveguide-integrated silicon based-optoelectronic modulators have been particularly studied as a key building block for silicon photonics. In term of active devices, Ge-rich Ge/SiGe quantum well (QW) waveguides are promising for compact and low power consumption electro-absorption modulators, thanks to the demonstration of direct gap related optical transitions in these structures. For passive functionalities, silicon nitride (SiN) waveguide could be studied as a promising alternative to Si waveguide for future dense wavelength division multiplexing (WDM) system. The refractive index of SiN is low enough to provide good fabrication tolerance and compact photonic circuit. Moreover, SiN thermo-optical coefficient and two photon absorption are much less significant than those of Si. Previous works focused on integration of such passive SiN component with active Germanium (Ge) optoelectronic components such as Ge photodetector through Si waveguides on SOI wafer. This paper studies a new integration approach between passive SiN waveguide and Ge/SiGe multiple quantum wells (MQWs) optoelectronic modulators. Photocurrent measurements at different bias voltages demonstrated strong optical modulation within the O-band telecommunication wavelength (1.26 – 1.36 µm) from Ge/SiGe MQWs, while 3D-FDTD calculations confirm a compact and efficient integration with SiN waveguide using butt coupling approach on Si wafer.

Speaker: Dr Papichaya Chaisakul (Kasetsart University and Université Paris-Sud)

134 Feasibility study of a dual wavelength laser cleaner

A dual wavelength laser system providing emissions of 1064 nm and 532 nm was developed for cleaning applications. In this study, cleaning of surface layers of paints with the dual wavelength laser system was demonstrated. The experiments combined with an on-line monitoring technique were carried out to investigate the removal various paint types and thicknesses. The results reveal that the laser system was able to control the depth of material removed. The cleaning efficiency was evaluated with varied conditions. With several advances, the dual wavelength laser cleaner operating in infrared and visible region will become an establish tool in non-contact cleaning applications.

Keywords: Laser cleaning, Dual wavelength laser, Paint removal

Speaker: Kanokwan Chongcharoen

135 Development of a compact transmission Raman spectroscopy for in field analysis

In this research, we describe the construction of a compact transmission Raman spectroscopy that has been developed for on-site determination of chemical analysis. The system consists of an inexpensive green laser pointer emitting less than 20 mW of 532 nm radiation used for excitation, a notch filter for blocking light around 532 nm and a portable spectrometer (Avantes, AvaSpec-ULS3648 ) for detection. The notch filter has a spectral operating range from 620 to 980 nm corresponding to Raman shift in the wave number range of 615-8797 cm$^{-1}$ with respect to 532 nm excitation. Several different samples including both solids (acrylic and polydimethylsiloxane) and liquid (limonene and ethanol) are qualitatively tested using our instrument and the results are in good agreement with literature data. The quantitative analysis of the water-ethanol binary mixture with various volume concentrations (12.5%, 37.5%, 50%, 62.5%, 75% and 100%) is also demonstrated. From this work, a reliable Raman detection capability for material analysis in the field is readily apparent.

Speaker: Mr Piyawat Kaewjaijong (Physics Department, Faculty of Science and Technology, Thammasat University)

136 Optically Remote Noncontact Heart Rates Sensing Technique

Heart rate monitoring via optically remote noncontact technique was reported in this research. A green laser (5mW, 532 ± 10 nm) was projected onto the left carotid artery. The reflected laser light on the screen carried the deviation of the interference patterns. The interference patterns were recorded by the digital camera (Canon EOS 1100D).The recorded videos of the interference patterns were frame by frame analyzed by 2 standard digital image processing (DIP) techniques, Block Matching (BM) and Optical Flow (OF) techniques. The region of interest (ROI) pixels within the interference patterns were analyzed for periodically changes of the interference patterns due to the heart pumping action. Both results of BM and OF techniques were compared with the reference medical heart rate monitoring device (Polar FT7) by which a contact measurement using pulse transit technique. The results obtained from BM technique was 74.67 bpm (beats per minute) and OF technique was 75.95 bpm. Those results when compared with the reference value of 75.46 ± 1 bpm, the errors were found to be 1.05% and 0.65%, respectively.

Speaker: Ms Waraporn Thongkongoum (Department of Physics, KMUTT)

137 Closed-form formulae of effective parameters of stacked fishnet metamaterial

A stacked fishnet metamaterial with a unit cell comprising a metallic hole-array layer and an insulator layer has been expected to exhibit hyperbolic dispersion. Here, we propose new closed-form formulae of effective parameters of the stacked fishnet metamaterial working at long-wavelength regime. These simple effective parameters are derived by applying the coupled-mode analysis to obtain the reflection and transmission coefficients which are then compared with those of a homogenized structure. The effective parameters show that the stacked fishnet metamaterial can behave as both type-II hyperbolic medium and elliptical medium depending on the filling ratio of the hole-array layer, dielectric constant of a dielectric layer, dielectric constant of a material filling the hole-array, and the excitation strength of an incident light on the hole-array. Importantly, the transition wavelength is inversely proportional to the square root of the filling ratio of the hole-array layer meaning that deep-subwavelength hyperbolic dispersion can be achieved with small filing ratio. This finding will greatly aid the design of deep-subwavelength imaging devices and optical lithography with the long-wavelength radiations.

Speaker: Dr Piyawath Tapsanit (King Mongkut’s Institute of Technology Ladkrabang)

138 Ultra-high green light transparency coating on 1D photonic crystal structure

The anti-reflective (AR) coatings have been regarded as one of the promising options to improving an efficiency of light transmission. In this research, we design the ultra-high anti-reflective layer structure. By using the specification properties of 1D photonic crystal, the periodical stack layer of tantalum pentoxide (Ta$_2$O$_5$) and molybdenum disulfide (MoS$_2$) in borosilicate glass (BK7) have been modified with a graphene as a defect layer for the wavelength selective transmission enhancement. The FDTD simulations have shown an extremely transparency for 0.283% of reflection at wavelength 505.613 nm and agreed with analytical results.

Speaker: Mr Teanchai Chantakit (Department of Physics, Kasetsart University)

A4: Plasma and Nuclear Fusion

Conveners: Dr Nopparit Somboonkittichai (Department of Physics, Faculty of Science, Kasetsart University), Dr Peera Pongkitiwanichakul (Mahidol University)

139 A Characterization of Portable HF Air Plasma Jet

A new portable low temperature plasma jet system is developed using ambient air as plasma gas. This atmospheric pressure plasma source is rich sources of reactive oxygen and nitrogen species (RONS) which play crucial roles in biomedical applications. Especially, Nitric oxide radical (NO), hydroxyl radical (OH) and ozone ($O_3$) in this plasma source have been suggested to be powerful agents in wound healing, cancer therapy, sterilization, and dentistry. By varying the air flows, the plasma source can be optimized for nitric oxide, ozone and hydroxyl radical production. Optical emission spectroscopy (OES) was used to determined OH radical in the effluent of the plasma source for varied air flows. The concentration of NO and $O_3$ has been investigated and measured by absorption spectroscopy and electrochemical detector at variable gas flows. Correlations between plasma parameters and concentrations as well as temperature of the effluent of the plasma source will be reported and discussed in this report.

Keyword: portable plasma jet, atmospheric pressure plasma, reactive oxygen and nitrogen species, biomedical applications.

Speaker: Phuthidhorn Thana

140 Effects of the temperature on the reconnection properties

In magnetized plasma systems, magnetic reconnection is the most important process in converting the magnetic energy into the kinetic energy of plasma. It is conventionally thought that the outflow speed and the reconnection rate depend only on the strength of the upstream magnetic field and the upstream plasma density. However, using fully kinetic particle-in-cell simulations of collisionless reconnection with different values of temperature, we show surprising results that, unlike the conventional belief, the outflow speed and the reconnection rate decrease when the temperature increases. The physics of these unexpected results will also be discussed.

Speaker: Dr Kittipat Malakit (Thammasat University)

141 Development of TPF-1 Plasma Focus for Education

The plasma focus is a device that uses high voltage and electromagnetic force to induce plasma generation and acceleration, in order to cause nuclear reactions. Radiation of various types (X-ray, gamma ray, electrons, ions, neutrons) can be generated using this method during the pinch phase, thus making the plasma focus able to serve as a radiation source. Material testing, modification, and identification are among the current applications of the plasma focus. Other than being an alternative option to isotopic sources, the plasma focus, which requires multidisciplinary team of personnel to design, operate, and troubleshoot, can also serve as an excellent learning device for physics and engineering students in the fields including, but not limited to, plasma physics, nuclear physics, electronics engineering, and mechanical engineering. This work describes the parameters and current status of Thai Plasma Focus 1 (TPF-1) and the characteristics of the plasma being produced in the machine using a Rogowski coil.

Speaker: Dr Roppon Picha

142 Performance Optimization of ITER and DEMO Plasmas in the Presence of Internal Transport Barrier

This work investigates performance optimization of ITER and DEMO plasmas in the presence of internal transport barrier. The optimization is carried out using simulation results of BALDUR integrated predictive modelling code. In these simulations, a combination of a neoclassical transport model NCLASS and an anomalous transport model Multimode model is used. The boundary condition is described at the top of the pedestal, which is calculated theoretically based on a combination of magnetic and flow shear stabilization pedestal width scaling and an infinite-n ballooning pressure gradient model. The toroidal flow calculation is based on NTV (neoclassical toroidal viscosity) toroidal velocity model. Time evolution of plasma temperature and density profiles of ITER- and DEMO-like (Japanese and Korean) plasmas are simulated with internal transport barrier (ITB). Several engineering parameters such as plasma current, magnetic field, ion and impurity (Beryllium and Carbon) densities are varied. The aim of this study is to identify the optimization point between plasma performance i.e. central temperature, densities and total fusion power output, and impurity accumulation. Though transport barriers can improve plasma performance, the significant accumulation of impurity in plasma core can lead to an enhancement of radiation loss.

Speaker: Dr Boonyarit Chatthong (Department of Physics, Faculty of Science, Prince of Songkla University)

143 Predictive Simulations of Pellet Injection in ITER and DEMOs

The impacts of pellet mass ablation and deposition that consider the effect of the

particle drift due to the gradient of magnetic field are investigated for

International Thermonuclear Experimental Reactor (ITER) and Demonstration

Nuclear Fusion Power Stations (DEMOs). In the core area, the plasma profiles are

predicted by the TASK/TR code in which the core transport models consist of a

combination of the MMM95 anomalous transport model and NCLASS neoclassical

transport. The pellet ablation in the plasma is described using neutral gas

shielding (NGS) model with inclusion of the $\nabla B$-induced $E\times B$ drift

of the ionized ablated pellet particles. These models are implemented in the HPI2

code that is coupled with the TASK/TR code. It is found that the high-field-side

(HFS) injection can deposit the pellet mass deeper than the injection from the

low-field-side (LFS) due to the advantage of the $\nabla B$-induced drift. The

optimized injection scenarios for achieving the highest fusion performance for

these reactors are also reported in this study.

Speaker: Mr Rungsin Kongkerd (Department of Physics, Faculty of Science, King Mongkut’s University of Technology Thonburi, Bangkok, Thailand)

144 Investigation of plasma performance and formation of transport barriers based on bifurcation concept

This research study plasma performance in fusion Tokamak system by investigating parameters such as central plasma pressure and particle density in the presence of an ETB (edge transport barrier) and an ITB (internal transport barrier). The plasma is modeled based on bifurcation concept using a suppression function that can result in formation of transport barriers. In this model, thermal and particle transport equations, including both neoclassical and anomalous effects, are solved simultaneously in slab geometry. The neoclassical coefficients are assumed to be constant while the anomalous coefficients depend on gradient of local pressure and density. The suppression function, depending on flow shear and magnetic shear, is assumed to affect only on the anomalous channel. The flow shear can be calculated from the force balance equation, while the magnetic shear is calculated from the given plasma current. It is found that as the position of driven current peak is moved outward from the plasma center, the central pressure is increased. But at some point it starts to decline, mostly when the driven current peak has reached outer half of the plasma. The higher pressure value results from the combination of ETB and ITB formations. The drop in central pressure occurs because ITB starts to disappear.

Speaker: Ms Jintana Pakeewanich (Prince of Songkla University)

J.Pakeewanich fullpaper spc2017.docx

J.Pakeewanich fullpaper spc2017.pdf

145 Calculate Argon Plasma Density Generate by UNU/ICTP Plasma Focus Device

A plasma focus (PF) device is device to generate plasma which is applied in ion acceleration, material surface modification and fusion reaction source. For plasma fusion is interest topic to study. Calculating plasma parameters such as plasma density and plasma temperature is importance to find the optimum condition for their applications. In this research uses Lee model code to calculate the plasma parameters under the 3.3 kJ UNU/ICTP configurations, and the operating pressure is 1.0 mbar, 1.5 mbar, and 2.0 mbar. These parameters were predicted at the position 7 cm, 9 cm, 11 cm and 13 cm respectively. From the results, plasma temperature are between 1.57 × 105 to 4.50 × 105 K and plasma density are between 2.11 – 7.55 g/m3. The results are shown that the density is depended directly with the operating pressure, but the plasma temperature isdepended inversely with the pressure. The dynamics of plasma is affected by Lorentz force is causes of these results because both the plasma temperature and plasma density in each position varied with this force directly. The further work, studying the plasma dynamics must be included collision between particles in the plasma that is close to the real phenomena.

Speaker: Mr Dusit Ngamrungroj (KMUTNB)

146 Energy transfer between particles & electromagnetic fields in laser-produced plasma simulations.

Laser-produced plasma experiments are widely conducted for several purposes ranging from using for initial confinement plasma to the comparison with supernovae. The experiments themselves cannot tell the underlying microscopic phenomena therefore we use particle-in-cell simulations to demonstrate the dynamics of particles and electromagnetic fields. In this work, we focus on the energy transfer between particles and fields. The results show that the characteristics of the energy transfer depend greatly on particles’ gyro-radius.

Speaker: Peera Pongkitiwanichakul (Kasetsart University)

147 Understanding roles of neutrons in advanced fusion reactors

The Deuterium-Tritium (DT) reaction is the key reaction in fusion reactors; leading to neutron and helium production. Most of the fusion energy (>80%) in such reaction is carried away by neutron. Conversion of neutron kinetic energy to any other usable form is very important for power generation in fusion reactors. The successful reactor design is thus highly dependent on this energy conversion. Only a few nuclides are effective for such purpose. On the other hand, neutrons as uncharged particle does not feel the Coulomb interaction and hence undergo nuclear reactions with materials surrounding the reactors, namely, the innermost wall which facing DT plasma, structural materials, vacuum vessel, magnets, etc. Some of these reactions lead to hydrogen and helium production in the materials. With the reactor working conditions, bubbles are formed accordingly, and embrittlement takes place in turn; therefore, shortening the lifetime of reactor materials. With the neutron fluence reaching 10$^{22}$ n/m$^2$ in many advanced reactor design, these adverse effects cannot be simply ignored. Understanding its roles will help balancing the two faces of neutrons; thus better energy conversion and extending the materials performance. This contribution summarizes some of the latest updates about energy-converted materials and activation reduced materials.

Speaker: Dr Dangtip Somsak (Mahidol University)

Physics Project Competition

A5: Nanoscale and Surface

Conveners: Prof. Sirikanjana Thongmee (Department of Physics, Kasetsart University), Prof. Weeraphat Pon-on (Department of Physics, Kasetsart University)

148 Recent Development of Nanoparticle Thin Films Prepared by Sparking-off Metal Wire Tips

Nanoparticle thin films have a vast range of applications in various fields due to their superior properties. There are a number of methods for nanoparticle thin film coatings, for example spray pyrolysis, electrodeposition, spin coating and sol-gel process. However, these methods are either a multistep synthesis or require the use of toxic substances. The sparking method is a onestep, simple and cost-effective process. It can be used to prepare nanoparticles and nanoparticle-thin films by applying a high voltage across any two metal wire tips. This talk will cover effects of electric and magnetic fields on film morphology and crystalline phase formation. Preparartion and characterisation of various noble metals, metal oxides and binary oxides nanoparticle thin films will be presented. It was found that the electric and magnetic fields enhanced the growth rate and uniformity the films while the magnetic field also altered a phase formation. Review of the sparked nanoparticles or nanoparticle thin films for some potential applications will be addressed.

Speaker: Dr Pisith Singjai (Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand)

149 Colorimetric plasmon sensor for mercury ion detection using gold nanoparticles

In this research, we demonstrate a colorimetric plasmon sensor for the determination of mercury ions, which are toxic heavy metal ions. Colorimetric detection by the naked eye is certainly the most simple and convenient diagnostic method, especially when it does not require any complex optical or electrical systems. Colorimetric method using gold nanoparticles (AuNPs) is based on changes in the resonance wavelengths of localized surface plasmon resonance (LSPR) that exhibit different colors depending on their size and shape. AuNPs in an average size 18 nm are mixed with urea in a proper ratio, which exhibits selective response to mercury ions as a result of color change from red to violet. The reason for the color change is due to the aggregation of AuNPs induced by the coordination complex between mercury ions and urea on the surface of nanoparticles. The results in an inter-particle plasmon coupling effect are followed by a shift in the LSPR absorption band in the visible region of spectra from 521 nm to 547 nm. Therefore, the change in the color of the LSPR band of AuNPs is used as a colorimetric sensing probe to monitor the concentration of mercury ions in the samples. The results show a linear relationship between absorbance intensity of AuNPs and the concentration of mercury ions which can be translated the detecting behaviors into color changes discernible by the naked eye. In addition, the detection limit of our method is 250 $\mu$M.

Speaker: Ms Thananan phetkongtong (Physics Department, Faculty of Science, Thaksin University)

150 Study of the Mechanism how Carbon Nanoparticles Can Improve the Mechanical Properties of Natural Rubber using Multi-scale Molecular Dynamics Simulation

Pure natural rubber (NR) has low durability and elasticity, which become a major bottleneck for practical use. To overcome the limitation, in general, the adding of carbon black and silica particles is applied$^{1,2}$, but carbon black has an effect of polymer cracking. Interestingly, the fullerene (C60) and carbon nanotube (CNT) can be used as rubber additive, resulting in the significant improvement of rubber mechanical properties as well as the thermal properties$^3$. However, the mechanism of how the carbon nanoparticles reinforce rubber is still unclear. None of proper microscopic picture is provided to explain such filler reinforcement. Here, we study the molecular mechanism of how carbon nanoparticles improve the mechanical properties of NR. The atomistic and coarse-grained (CG) MD simulations are performed. The CG model of polyisoprene (the major component of NR) was developed based on MARTINI force field using "hybrid approach" which both structural and thermodynamic properties are used as a target during the parameterization. The advantages in time and length scales of CG modeling allow us to investigate the interactions between carbon nanoparticles in the NR at various concentrations and their size. The dispersion and aggregation of nanoparticles in the NR are expected to play an important role in improving mechanical properties of NR composite. The understanding of how C60 and CNT alter the physical NR properties is useful to produce more well-designed rubber composites preparation technique and develop rubber applications.

References:

1. Hundiwale, D. G.; Kapadi, U. R.; Desai, M. C.; Bidkar, S. H. Journal of Applied Polymer Science 2002, 85, 995-1001.
2. Heinrich, G.; Klüppel, M.; Vilgis, T. A. Current Opinion in Solid State and Materials Science 2002, 6, 195-203.
3. Sae-Oui, P.; Thepsuwan, U.; Thaptong, P.; Sirisinha, C. Adv Polym Tech 2014, 33.

Speaker: Mr Jiramate Kitjanon (1. Department of Physics, Faculty of Science, Kasetsart University, Bangkok, 10900, Thailand 2. Computational Biomodelling Laboratory for Agricultural Science and Technology (CBLAST), Faculty of Science, Kasetsart University, Bangkok 10900, Thailand )

151 Novel atmospheric process for large area perovskite solar cells via modified 2 step method

Lead halide perovskite solar cells (PVSCs) have been exhibiting high efficiency by using abundant materials and availability on flexible substrates with easy fabrication process. However, to fabricate the perovskite devices for large area are facing many problems such as surface coverage and quality of perovskite crystalline thin film. Here, we report the way to fabricate perovskite solar cell outside glovebox (humidity less than 40%) for small and large scale area by modifying the 2 step method with structure FTO/TiO$_2$Perovskite/spiro-oMeTAD/Au. The modification of 2 step method is based on the “spin-washing” during the second step: methylammonium iodide solution dipping. The films after dipping were washed with IPA at difference spin speed in order to remove non-reactive material on the surface of perovskite thin film. We observed perovskite crystalline morphology was changed when we change the washing spin speed. Finally, we succeeded to fabricate perovskite solar cell outside glovebox and observed the maximum PCE for small devices (0.09 cm$^2$) at 12.7% and large area devices(1 cm$^2$) at 10.3%.

Speaker: Atthaporn Ariyarit (Keio University)

152 Optical properties of Cu(In,Ga)Se$_2$ thin films with ultra-thin $\beta$-Cu(In,Ga)$_3$Se$_5$ capping layer

The presence of $\beta$-Cu(In,Ga)$_3$Se$_5$ phase on Cu-poor Cu(In,Ga)Se$_2$ thin film surface could play an important role in the efficiencies of Cu(In,Ga)Se$_2$ thin film solar cells. The $\beta$-Cu(In,Ga)$_3$Se$_5$ with various thicknesses were deposited after a completion of the three-stage co-evaporation process of Cu(In,Ga)Se$_2$ films. The optical absorption measurement is used to obtain their optical band gap energies. The optical band gap energy of the $\beta$-Cu(In,Ga)$_3$Se$_5$ and Cu(In,Ga)Se$_2$ thin films, themselves, are 1.44 and 1.15 eV, respectively. The absorption edges of CIGS thin films with $\beta$-Cu(In,Ga)$_3$Se$_5$ layer shift towards shorter wavelengths. As a result, the band gap energy increases as the thickness of Cu(In,Ga)$_3$Se$_5$ increases. Likewise, the temperature-dependent and excitation power-dependent photoluminescence (PL) spectra for CIGS with various thicknesses of $\beta$-Cu(In,Ga)$_3$Se$_5$ are identified as donor-to-acceptor pairs (DAPs) and free (conduction band) -to-bound (acceptor) transitions. The higher PL transition energy is found with $\beta$-Cu(In,Ga)$_3$Se$_5$ less than 80 nm thick. These minimal defect layers results in larger band gap energy.

Speaker: Ms Boonyaluk Namnuan (Department of Physics, Faculty of Science, Chulalongkorn University)

153 Microspheres pattern forming using self-assembly template prepared by convective deposition

Stacks pattern of microspheres and nanoparticles can be deposited by layer-by-layer coating with several methods. In this work, we fabricated two monolayers of polystyrene microparticle by convective horizontal deposition. For initial layer, glass substrate was dragged with velocity of 25 $\mu$m/s, and applied horizontal vibration with frequency of 50 Hz in order to supply higher kinetic energy for better assembly. Size of polystyrene microparticles was 3.2 micrometer for this initial template coating and for the second layer microparticle size was varied with 0.93, 1.00, and 1.50 micrometer. The packing of second layer was investigated by scanning electron microscope. The filling quality of second coating layer strongly depend on particle size and dragging velocity. For the same dragging speed, the microparticle of 0.93 micrometer trended to be well arrangement on the initial template with honeycomb pattern.

Speaker: Nonthanan Sitpathom

154 Characteristics and Magnetic Properties of Anchored Fe$_3$O$_4$ Nanoparticles in Bacterial Cellulose Scaffold

In this work, bacterial cellulose (BC) was biosynthesized by Glucanobacter xylinum bacteria. Fe$_{3}$O$_{4}$ nanoparticles under different concentrations were ex-situ impregnated into the BC structure. The BC pellicles in both never-dried and freeze-dried states were used as the templates to form BC-Fe$_{3}$O$_{4}$ nano-composites. Morphological studies of the samples indicated that the 3-dimensional networks of fine fiber structure were enveloped by Fe$_{3}$O$_{4}$ nanoparticles. Moreover, the Fe$_{3}$O$_{4}$ nanoparticle was dispersed without any obvious agglomeration. The FTIR and XRD analysis showed that both never-dried and freeze-dried samples have almost similar results. Nevertheless, the saturation magnetization (M$_{s}$) of the never-dried samples was found to be higher than the freeze-dried samples, at the same Fe$_3$O$_4$ concentration. It was attributed to infiltration ability of the nanoparticles in the never-dried environment.

Keywords: bacterial cellulose; nanoparticles; characteristics; magnetic properties

Speaker: Nipaporn Sriplai (Khon Kaen University)

Thursday 25 May

A7: Astronomy I

Conveners: Dr Maneenate Wechakama (Kasetsart University), Dr Peera Pongkitiwanichakul (Mahidol University)

155 Search for Galactic Dark Matter from Gamma-ray Spectral Lines with Fermi-LAT Data

Most of the matter in the universe is invisible and is known as dark matter (DM). Weakly Interacting Massive Particles (WIMPs) are possible theoretical candidates to explain DM. Hypothetically, WIMPs can be detected indirectly by their annihilation or decay products. A possible product is gamma ray. Many DM profile models predict higher density of WIMPs near the Galactic center. In this work, we consider monochromatic gamma-ray emission from the Galactic center region measured by the Large Area Telescope (LAT), the main instrument onboard the Fermi Gamma-ray Space Telescope. We present preliminary results of the analysis of gamma-ray spectral lines to search for DM annihilation or decay signals using the latest version of the LAT data.

Speaker: Ms Natthakan Thanapreechanan

156 Simulations of the South Pole Neutron Monitors

Cosmic rays are high energy particles traveling nearly the speed of light through space. When cosmic rays enter the earth’s atmosphere, they interact with nucleons and start a chain reactions that produce showers of secondary particles, including neutrons, that can reach the surface These neutrons are detected by neutron monitors placed around the globe. The number of neutrons recorded by a neutron monitor depends on the state of the earth’s magnetosphere, which can be modulated by solar activity. In this sense neutron monitors observe space weather. UW-River Falls maintains neutron monitors at the South Pole, McMurdo Station, and on campus. To better understand the data from neutron monitors, Monte Carlo simulations are done. A response function, which characterizes the rates of particles detected, can be used to compare different configurations of neutron monitors. Simulations of different types of neutron monitors with the same incident flux of cosmic rays and same atmospheric conditions are used to investigate the response functions. We determined the response function of five different types of neutron monitors without simulating the buildings housing them. We then extended the simulations to explore the effects the physical environment has on the count rates of twelve neutron monitors tubes at the Amundsen-Scott Station at the South Pole. Results of the simulated response functions of five types of neutron monitors tubes along with the preliminary results of environmental effects on twelve neutron monitors at the South Pole will be presented.

Speaker: Mr Mitchell Ahlswede (University of Wisconsin-River Falls )

157 Time Variations of Oxygen Emission Lines and Solar Wind Dynamic Parameters in Low Latitude Region

Aurora phenomenon is an effect of collision between precipitating particles with gyromotion along Earth’s magnetic field and Earth’s ionospheric atoms or molecules. The particles’ precipitation occurs normally around polar regions. However, some auroral particles can reach lower latitude regions when they are highly energetic. A clear emission from Earth’s aurora is mostly from atomic oxygen. Moreover, the sun’s activities can influence the occurrence of the aurora as well. This work studies time variations of oxygen emission lines and solar wind parameters, simultaneously. The emission’s spectral lines will be observed by Medium Resolution Echelle Spectrograph (MRES) along with 2.4-m diameter telescope at Thai National Observatory, Intanon Mountain, Chiang Mai, Thailand. Oxygen (OI) emission lines will be calibrated by Dech-Fits – spectra processing program and Dech95 – 2D image processing program. The correlation between oxygen emission lines and solar wind dynamics will be analyzed. This result could be an evidence of the aurora in low latitude regions.

Speaker: Ms Paparin Jamlongkul (Graduate School, Chiang Mai University)

A6: Condensed Matter and Accelerators

Conveners: Dr Papichaya Chaisakul (Kasetsart University and Université Paris-Sud), Prof. Pakpoom Reunchan (Kasetsart University)

158 Non-centrosymmetric CePt$_3$Si and CePt$_3$B and their mechanical properties

The first non-centrosymmetric heavy fermion superconductor CePt$_3$Si [1], crystallizing with CePt$_3$B -type, without an inversion symmetry (one of the key symmetries for Cooper pairing) shows a number of novel physical properties. In order to get insight into the pressure dependence of the strong electron correlations in these materials the present paper provides mechanical property data (elastic moduli and hardness both at room temperature as well as thermal expansion in the range from 4.2 to 670 K) for both single and poly-crystalline CePt$_3$Si and its prototype compound CePt$_3$B.
The experimental data are backed by first-principles (ab-initio) calculation. Resonant ultrasound spectroscopy was used to determine elastic properties (Young’s elastic modulus E and Poissons ratio $\nu$) via the eigenfrequencies of the sample and the knowledge of sample mass and dimensions. Bulk modulus and shear modulus were calculated from E and $\nu$, and with Anderson’s equation the respective Debye temperatures were derived. In addition, ab-initio DFT calculations were carried out for both compounds. A comparison with parameters evaluated from these first-principles computations with the experiments revealed, in general, good agreement.
Positive and negative thermal expansion values obtained from CePt$_3$Si single crystal data are fairly well explained in terms of the crystalline electric field model, using CEF parameters derived recently from inelastic neutron scattering. The DFT calculations, in addition, demonstrate that the atomic vibrations keep almost unaffected by the antisymmetric spin-orbit coupling present in systems with crystal structures having no inversion symmetry. This is opposite to electronic properties, where the antisymmetric spin-orbit interaction has shown to distinctly influence features like the superconducting condensate of CePt$_3$Si.

[1] E. Bauer, G. Hilscher, H. Michor, C. Paul, E.W. Scheidt, A. Grybanov, Yu. Seropegin, H. Noel, M. Sigrist and P. Rogl; “Heavy Fermion Superconductivity and Magnetic Order in Non-centrosymmetric CePt$_3$Si”, Phy. Rev. Lett., 92, 027003 (2004)1-4.

Speaker: Dr Gerda Rogl (Christian Doppler Laboratory Univ. and Univ of Technology, Vienna, Austria)

159 The structural phase transition of Ga(Mn)N under high pressure

Gallium nitride doped with small concentration of manganese (Ga_xMn_1-xN) is one of the most diluted magnetic semiconductors which used for the spintronic applications. In this work, the Ga₃₁Mn₁N₃₂ in the zinc-blende (ZB) and rocksalt (RS) structures were investigated. We employed the ab-initio density functional theory (DFT) within the generalized gradient approximation (GGA) to study electronic and magnetic properties, such as the band structure, the density of state and the magnetic moment. The structural phase transitions under pressure up to 60 GPa were also studied. We found that the Ga₃₁Mn₁N₃₂ in ZB phase is stable at ambient pressure, and change to the RS phase about 42 GPa. Finally, our calculations are in consistent with other experimental and theoretical literature.

Speaker: Mr Akkarach Sukserm (Chulalongkorn University)

160 Suppression of two-dimensional electron gases at oxide surfaces across the ferroelectric transition

The discovery of a two-dimensional electron gas (2DEG) at the LaAlO3/SrTiO3 interface has set a new platform for all-oxide electronics which could potentially exhibit the interplay among charge, spin, orbital, superconductivity, ferromagnetism and ferroelectricity. In this work, by using angle-resolved photoemission spectroscopy and conductivity measurement, we have studied the behavior of photon-induced 2DEGs at the bare surfaces of ferroelectric oxides. We found that the onset of ferroelectric polarization induces a delocalization transition for the quantum well states at the surface. We propose that this suppression could be due to that the ferroelectric polarization makes the quantum well states become spatially delocalized along the direction perpendicular to the surface and hence changes the conductivity nature. This finding suggests an opportunity for controlling the 2DEG at a bare oxide surface (instead of interfacial system) by using both light and ferroelectricity.

Speaker: Worawat Meevasana (School of Physics, Suranaree University of Technology)

161 ETCHING BEHAVIORS OF TUNNELING MAGNETO RESISTIVE (TMR) MATERIALS BY ION BEAM ETCHING SYSTEM

In microelectronic industry, lithography and patterning by using ions bombard on the surface to remove atoms of material is a very important process. In data storage manufacturing, ion etching process is chosen to prepare a specific pattern under the read-write head of the hard disk drive (HDD) to form an “air bearing surface” or ABS. This makes the HDD head can float or slide over the surface of the hard disk platter. In this work, we use the Monte Carlo-based simulation package to calculate the etching yield of different materials in the head’s structure. The plasma characteristic in the industrial-size ion beam etching (IBE) system has been studied by the special plasma diagnostic. Plasma parameters such as floating potential, plasma potential, electron temperature and ion current density are obtained from plasma I-V curve characterization. The sputtering yields of materials are maximum when an incident angle is about 70 degree to the normal surface. The floating potential of plasma in the system with the ion\electron compensation from plasma bridge neutralizer (PBN) is calculated. Other results will be more discussed further.

Speaker: Mr Napakan Wongpanit (Chulalongkorn University)

162 Thermoelectric Half Heusler phases to harvest waste heat

Thermoelectric materials have the ability to convert a heat flow into an electrical charge carrier flow (energy flow). TiNiSn-based thermoelectric half-Heusler phases (noncentrosymmetric, cubic MgAgAs-type) have proven to be excellent thermoelectrics. The large-scale production and particularly nanostructuring of materials by preferably system-inherent phases need a profound knowledge not only of isothermal phase relations, temperature dependent solubilities but also of the solidification behavior.
The present paper covers a detailed experimental investigation of the constitution of the [Ti,Zr]-Ni-Sn systems including a liquidus projection and a Scheil diagram, as well as a CALPHAD calculation of the entire constitution diagrams. For the binary systems TiNiSn-ZrNiSn and TiNiSn-HfNiSn, thermodynamic spinodal/binodal curves have been determined from solubility data and DFT calculations. With the relevant elastic moduli also the corresponding critical points of coherent spinodal demixing were calculated.
From a series of compounds Ti$_\text{1-x-y}$Zr$_\text{x}$Hf$_\text{y}$NiSn and respective Sn/Sb substituted alloys the thermoelectric behavior was characterized in the temperature range from 4.2 to 875 K. Due to a particularly low thermal conductivity at a high Seebeck coefficient, Hf-containing n-type alloy reached a figure of merit ZT = 1.5 at 850 K whereas for Hf-free, n-type Ti$_\text{0.5}$Zr$_\text{0.5}$NiSn$_\text{0.98}$Sb$_\text{0.02}$ a ZT ~ 1.2 at 850 K was found yielding an thermoelectric leg-efficiency of $\eta$ ~ 11$%$. These excellent TE data on spinodally demixed alloys prove that Hf-free and therefore cheap half-Heusler alloys can be promising materials for a large scale production route. The experimental data (backed by SEM/TEM analyses) are compared with DFT calculations and discussed.

Speaker: Prof. Peter Rogl (1Christian Doppler Laboratory for Thermoelectricity at the Institute of Materials Chemistry and Research, University of Vienna)

163 Theoretical investigation of hybrid organic-inorganic perovskite

The light shone upon hybrid organic−inorganic perovskite (HOIP) has never been brighter. Many researchers have claimed that this material could hold the key to the new era of photovoltaic technology, owing to its efficiency, both energetically and economically. Despite all its merits, perovskite solar cell is plagued by an indispensable draw back; it degrades precipitously under sunlight. Not only sunlight that has destructive effects on perovskites, humidity and high temperature also cause the compound to disintegrate. In this seminar, we present a review on structural properties of the archetypal perovskite, the methylammonium lead iodide perovskite, as reported by various experiments. The correlation between the ion disorder and structural instability, which ultimately leads to phase transition, is eminent. We also cover the most up-to-date reports on pressurization experiments. The effects of pressure on the material characteristics will be discussed.

Speaker: Vichawan Sakulsupich (Department of Physics, Faculty of Science, Chulalongkorn University, Bangkok THAILAND)

164 Helium separation of monolayer $C_2$N membrane under uniform strain

An efficient membrane for helium separation from natural gas is quite crucial for cryogenic industries. However, most experimentally available membranes fail in separating He from small molecules in natural gas, such as Ne, $H_2$, $O_2$, CO and $N_2$. Recently, a new 2D graphene-like sheet: $C_2$N was synthesized via a simple wet-logical reaction. $C_2$N has more advantage than among other porous 2D materials because it has large pore size of 5.52 Å. In this work, we calculated the energy barrier of gas molecules (Ne, $H_2$, $O_2$, CO, $N_2$) passing through the porous $C_2$N membrane by using first-principles calculations. The energy barrier of He, Ne, $H_2$, $O_2$, CO and $N_2$ are 0.029 eV, 0.070 eV, 0.067 eV, 0.128 eV, 5.817 eV and 0.070 eV, respectively. We found that energy barrier of He molecules is lowest among other gas molecules. This means $C_2$N can possibly separate He gas from natural gas. To reveal efficiency of membrane, the selectivity of He over Ne, $H_2$, $O_2$, CO, $N_2$ molecule has been calculated. The selectivity of He over Ne, $H_2$, $O_2$, CO, $N_2$ molecules respectively are 92.9, 32.4, 547, 1.46x$10^7$, and 4.37x$10^9$, respectively. Although energy barrier of He is lowest, selectivity clearly states that the $C_2$N membrane is not powerfully separate He gas from natural gas, especially from $H_2$ and Ne molecule. Moreover, we study the effect of applied uniform strain to the energy barrier and selectivity of membrane. We found that the energy barrier and the selectivity of gas molecule are exponentially lower as function of strain.

Speaker: Klichchupong Dabsamut

A7: Astronomy I

Conveners: Dr Maneenate Wechakama (Kasetsart University), Dr Peera Pongkitiwanichakul (Mahidol University)

165 Transmission spectroscopy analysis of inflated exoplanets

At present, over 3,500 exoplanets have been discovered. In addition to the discovery of new exoplanets, the characterization of planetary atmosphere is a rapidly developing area. One method that is used to study planetary atmosphere is transmission spectroscopy, which measures the variation of transit depth with wavelength. Inflated exoplanets are favorable for transmission spectroscopy, due to their large atmospheric opacities. GJ3470b, a hot inflated Neptune exoplanet, was observed using Thai telescopes between 2013 and 2016. The GJ3470b transmission spectroscopic result favour an H/He-dominated haze (mean molecular weight 1.08 $\pm$ 0.20) with high particle abundance at high altitude and methane in its atmosphere. Moreover, the primary photometric results of our 2016-2017 observation season targets will also be provided.

Speaker: Dr Supachai Awiphan (National Astronomical Research Institute of Thailand (NARIT), Thailand)

166 Reverberation Mapping of Hamburg/ESO Catalog Quasars

Quasars are a type of AGN with extremely bright luminosities in the optical region of the spectrum which are powered from the accretion process of in-falling matter into the SMBH near the center. This process creates notable features in the AGN spectrum including very broad emission lines which are emitted from the Broad-Line Region (BLR) outside of the SMBH. Although the geometry and the kinematics of the BLR are still not well understood, we are able to infer some basic information from the emission lines alone. Reverberation mapping is a method used to study the kinematics and geometry of the BLR and can also estimate the mass of the SMBH inside. This technique has been constantly improved and new spin-off techniques were created such as photometric reverberation mapping (PRM). In this study, we aim to use spectroscopic reverberation mapping and narrow band photometric reverberation mapping (PRM) to determine the BLR size of quasars through observing the H-beta emission line. Our quasar sample is drawn from the Hamburg/ESO catalog (HES) and photometric data is obtained from an on-going photometric monitoring program using the Thai Southern Hemisphere Telescope (TST). Data analysis is done using custom made python pipelines and publicly available software.

Speaker: Mr Bovornpratch Vijarnwannaluk (Chulalongkorn University)

167 Bare Neutron Counter and Neutron Monitor Response to Cosmic Rays during a 1995 Latitude Survey

Neutron monitors are ground-level detectors of cosmic ray-induced atmospheric secondary particles (mostly neutrons) that are employed world-wide to study variations in the flux of galactic cosmic rays and solar energetic particles in the GeV regime. The neutron monitor standard design (NM64) minimizes detector response to neutrons below $\sim$10 MeV produced by cosmic ray interactions in the ambient medium. Increasingly, however, such neutrons are of interest as a means of obtaining spectral information on cosmic rays, for studies of soil moisture, and for nuclear threat detection. Bare neutron counters, which lack the lead and polyethylene of NM64 monitors, can detect such neutrons, but comparatively little work has been done to characterize the dependence of their count rate on cutoff rigidity. We analyze data from three bare neutron counters operated on a ship together with a 3-tube NM64 monitor from November, 1995 to February, 1996 over a wide range of magnetic latitude, i.e., a latitude survey. When the ship was near land, the bare/NM64 count rate ratio was dramatically higher. Considering only data from open sea, the bare and NM64 pressure coefficients are not significantly different. We determine the response function of these bare counters, which is weighted to Galactic cosmic rays of lower energy than the NM64. This measurement of the response function may improve determination of the spectral index of solar energetic particles and Galactic cosmic rays from a comparison of bare and NM64 count rates.

Speaker: Dr Waraporn Nuntiyakul (Chandrakasem Rajabhat University)

168 Spectral detection of Oxygenic and Anoxygenic Photosynthesis on Extrasolar Planets like Proxima Centauri b.

Proxima Centauri (type – M5.5V, 3050K) is a red dwarf only 4 light yr away, whereas the Sun is type G2V (5780 K). Could oxygenic and/or anoxygenic photosynthesis exist on planet Proxima Centauri b and would we be able to detect it? The light regimes on Earth and Proxima Centauri b are compared to estimate the planet’s suitability for Chlorophyll a (Chl a) and Chl d-based oxygenic photosynthesis and for Bacteriochlorophyll (BChl)-based anoxygenic photosynthesis. Proxima Centauri b has low irradiance in the oxygenic photosynthesis range (400–749 nm: 64 to 132 $\mu$mol quanta m$^{-2}$ s$^{-1}$) but larger amounts of light is available for BChl-based anoxygenic photosynthesis (350–1100 nm: 724 to 1538 $\mu$mol quanta m$^{-2}$ s$^{-1}$). Remote sensing techniques are routinely used to monitor algal blooms and terrestrial vegetation on earth. Their spectral properties are well documented. If Proxima Centauri b can be visualized is should be possible to detect Chl a based photosynthesis on the planet based on the reflectance properties of any algae and vegetation present and the signatures of oxygenic photosynthesis such as the presence of oxygen and ozone. An integrating sphere spectrometer has been used to prepare reflectance spectra of oxygenic photosynthetic organisms (Synechocystis PCC6803, a blue green alga with only Chl a; the Chl a + b green alga Chlorella vulgaris, the diatom Chaetoceros sp with Chl a + Chl c1+c2 and the unusual Chl d+a organism, Acaryochloris marina. Estimates are made of what their reflectance spectra would look like irradiated by Proxima Centauri. Anoxygenic photosynthetic organisms are much less familiar to astronomers, astrobiologists and biologist in general. Evolutionarily it is known that anoxygenic photosynthesis predated oxygenic photosynthesis and so it is likely to be more common in the universe than anoxygenic photosynthesis. Rhodopseudomonas palustris (BChl a), Afifella marina (BChl a), Thermochromatium tepidum (BChl a), Chlorobaculum tepidum (BChl a + c) and Blastochloris viridis (BChl b) were used as representative anoxygenic photosynthetic organisms to estimate their reflectance. Chlorophylls (Chl) absorb blue and red light but BChls use blue and infrared light for photosynthesis. The difference in their reflectance spectra could be used to distinguish oxygenic from anoxygenic photosynthesis.

Speaker: Dr Raymond J. RITCHIE (Technology & Environment, PSU-Phuket)

169 SEARCHING FOR NEW MILLISECOND PULSARS WITH THE GBT INFERMI UNASSOCIATED SOURCES

The launch of the Fermi satellite in 2008 revolutionized gamma-ray pulsar astronomy
by enabling the discovery of many new millisecond pulsars (MSPs). The Fermi
Pulsar Search Consortium (PSC) has organized hundreds of radio observations of
pulsar-like Large Area Telescope (LAT) unassociated sources. Over the past seven
years, the PSC has discovered more than 70 new MSPs, compared to the 75 MSPs found in the 25 years prior to Fermi. The National Radio
Astronomy Observatory's Robert C. Byrd Green Bank Telescope (GBT) has played
the key role in the project by discovering almost half (34) of the new MSPs.
In this talk, I present the discovery and analysis of 16 new MSPs, 10 of which were uncovered by me personally.
The pulsars were found in GBT searches within the positional error boxes of 266
Fermi LAT sources, both at high Galactic latitudes and closer to
the Galactic plane. All new pulsars have phase-connected radio timing solutions,
and for 12 of them, gamma-ray pulsations were detected.
Twelve MSPs have Helium white dwarf (He-WD) companions and the other four are in so-called "spider" systems with
compact orbits and non-degenerate companions. We investigated
the relationship between radio and gamma-ray flux densities for all MSPs, confirming that there is almost no correlation between the two. We also investigated the
orbital period vs. companion mass relation for MSPs with He-WD companions
using a simple Monte Carlo technique, and found that the distribution of binary inclination angles is not random but possibly leans towards lower inclinations. For the four MSPs in compact orbits,
we examined flux density variability, as well as their optical light curves. We found that all four MSPs are eclipsing and that two of them exhibit strong diffractive scintillation. Finally, we found optical counterparts for two MSPs, one of which shows ellipsoidal modulations in its light curve, suggesting that the companion is filling its Roche lobe.

Speaker: Dr Siraprapa Sanpa-arsa (National Astronomical Research Institute of Thailand)

170 Massive gravity in higher dimension

Since Einstein’s general relativity or GR cannot explain our universe completely, physicists have tried to find the theory which can describe the dynamic of the universe. One of attempts is modification of GR or modified gravity. We are interested in two models of modified gravity. The first one is the higher dimensional gravity theory which explains the nature by considering GR with extra dimensions, and the second one is massive gravity in which graviton mass is given to GR. In this presentation, we consider the four-dimensional theory which is obtained from the dimensional reduction of the massive gravity in five dimensions. This theory is the one type of massive scalar-tensor theory. Interestingly, we found that the theory resembles the combination of quasi dilaton and mass varying theory of massive gravity. The cosmological models due to this theory are explored.

Speaker: Mr Ratchaphat Nakarachinda (The institute for fundamental study, Naresuan university)

171 Traversable Wormholes in Massive Gravity theory

Traversable wormhole or Morris-Thorne wormhole is one of wormholes to which human can travel. However, an exotic matter, the matter with negative pressure, must be included in order to construct such the wormhole. By introducing the cosmological constant into general relativity, it was found that one can minimize the existence of the exotic matter to a thin shell. In this presentation, we investigate possibility to construct the wormhole without the exotic matter in a modified gravity theory namely “massive gravity theory”. Massive gravity theory is a modified gravity theory in which a graviton acquires non-zero mass. For a class of solutions, we found that it is possible to obtain traversable wormhole without the exotic matter.

Speaker: Mr Nopadhol Kamma (the Institute for Fundamental study)

172 Constraints on Dark Matter Annihilation by Synchrotron Emission based on Planck Data

Synchrotron emission is a good probe for dark matter (DM) particles in the Universe. We search for DM annihilation signals in the Milky Way by using Planck data of synchrotron emission in the microwave bands. We investigate the production of dark matter annihilation into electrons and positrons by studying different channels. We look for upper limits of the mass of dark matter particles on the relevant cross-section obtained by Planck data at different wavelengths. According to our results, the dark matter annihilation cross-section into electron-positron pairs should not be higher than the canonical value for a thermal relic if the mass of the dark matter candidate is smaller than a few GeV. In addition, we also look for constraints on the inner slope of dark matter density profile in the Milky Way. Our results indicate that the inner slope of dark matter profile is between 1 to 1.5.

Speaker: Mr Chalit Muanglay (Department of Physics, Faculty of Science, Kasetsart University )

173 Radial velocity observations of OB1d association in NGC 1977

Radial velocity observations for members of the Ori OB1d association in the nebula NGC 1977 were obtained using the MRES spectrograph with the 2.4 m telescope at Thai National Observatory. Radial velocities of 2MASS J05352174-0453118, HD37059, HD294264 are detectable for the first time with a value of 30.02, 32.19 and 60.27 km/s, respectively. Combining the obtained radial velocities from this research with database proper motion, it was found that all observed star are moving in a different direction. This might be a result from the fact that Ori OB1d is dynamically young with active ongoing star formation. The association are small and loose. Members are less gravitationally bound and the cluster are expanding.

Speaker: Mr Watunyoo Patwong (Chiang Mai University)

A8: Instrument I

Conveners: Prof. Wiwat Wongkokua (Kasetsart University), Prof. Chatchawal Wongchoosuk (Kasetsart University)

174 Ultrasonic and Molecular Interaction Studies of Nanofluids

Nano fluids are engineered colloidal suspensions of nanoparticles in a base fluid. These nanoparticles are typically made of carbides or carbon nanotubes, metals, oxides and so on. Nanofluids are potential heat transfer fluids with enhanced thermo physical properties and heat transfer performance can be applied in many devices for better performances (i.e. energy, heat transfer and other performances). Nanofluid in solar collectors is another application where nanofluids are employed for their tunable optical properties. Using sonication, the dispersion of nano particles in the base fluid is made uniform. Ultrasonic velocity in a nanofluid depends on material density and elasticity. It can be measured using nanofluid Interferometer The viscosity of nanofluids can be determined BROOKFIELD viscometer. The density studies are made using Pyknometric method. Refractive index studies are done using Abbe Refractometer. Various molecular interaction parameters [1-3] like adiabatic compressibility, viscous relaxation time, inter molecular free length, free volume, internal pressure, etc can be analysed with the knowledge of ultrasonic velocity, viscosity and density and the results are discussed in the light of solute-solvent interaction. This kind of study helps to understand the behavior of nano-molecules with respect to changing concentration. Molecular interaction studies of Zinc oxide nanofluid will be discussed in this paper.

Keywords: Adiabatic Compressibility, Free volume, Nanofluids, Sonication, Ultrasonic velocity

Speaker: K Venkatramanan (Sri Chandrasekharendra Saraswathi Viswa Mahavidyalaya)

175 Non-Contact Radius Measurement Method of Spherical Standards

The diameter measurement of sphere is very important in dimensional metrology. The measurement of diameter is generally carried out by a comparison method or direct method using 1D linear measuring system. The probes touch both sides of the workpiece and the diameter is determined from displacement of the probes. The contact force is generally operated at 1N which yield deformation due to force of approximately 1 $\mu$m with uncertainty of ±0.1 $\mu$m. This system provides good performance but has a limitation when workpiece is made from soft matter or sensitive to scratch.
National Institute of Metrology (Thailand) developed a laser interferometer system which is equipped with reference spherical lens in order to non-contact radius measurement of spherical objects possible. Radius of completed sphere and partial sphere with radius range from 1 mm up to 50 mm can be measured with accuracy of ±2 $\mu$m.

Speaker: jariya buajarern (National Institute of Metrology (Thailand))

SPC2017_Jariya_ppt.pdf

176 Confirmation of the relative gravity measurement by the absolute gravimeter at NIMT

The local gravity measurement using relative gravimeter was confirmed to the reference absolute gravity station by National Institute of Metrology (Thailand); NIMT. Five known absolute gravity value stations were used in this confirmation. By applying the A-B-A measurement pattern, the time dependent of the relative gravity value at the reference station was calculated. Then the short term drift correction was introduce to the relative gravity reading of the loop. The relative gravity difference ($\Delta $g$_{rel}$ ) was compared to the absolute gravity difference ($\Delta $g$_{abs}$ ) between A-B stations. Five measurement loops were given the maximum difference between $\Delta $g$_{rel}$ and $\Delta $g$_{abs}$ of 0.012 mGal which is less than the absolute gravity uncertainty value of the station in that measurement loop. Therefore, the relative gravimeter is confirmed to report the local gravity value rely on the reference absolute gravity station using daily measurement loop with A-B-A pattern.

Speakers: Nattanan Woradet, Tasanee Priruenrom (National Institute of Metrology (Thailand))

177 Characteristics of Linear Variable Differential Transformer(LVDT) Probe for Gauge Blocks Calibration.

The LVDT probe is a very important component used in gauge blocks calibration via a mechanical comparative method. The probe is used to determine the central length difference between a reference gauge block and gauge block under-tested (UTC). Typically, an UTC and a reference gauge block have the same nominal length. However, some gauge blocks UTC are specially made for specific purpose where the reference gauge blocks with the same nominal length are not commercially available. Various reference gauge blocks are wrung in order to provide nominal length the same as that of the UTC. Wringing process is the troublesome step and causes larger measurement uncertainty. The lower accuracy is higher number of gauge block used to create reference gauge block, in order to improve accuracy of measurement, the LVDT probe was used at the longer range where the reference gauge block and the UTC don’t need to be the same nominal length. In this paper, characteristics of LVDT probe was investigated as it is related to the accuracy of the measurement result. Errors of LVDT probe came from non-linearity, calibration factor, retrace error, repeatability and maximum difference in length. A pair of gauge block, calculated by the Twyman-Green interferometer, length different range 5 $\mu$m to 250 $\mu$m was used in the study. Non-linearity of LVDT is evaluated by a simple linear regression model. The non-linearity of LVDT probe, calibration factor, retrace error, repeatability and maximum difference in length are 25 nm, 1.0003, 3 nm, 6 nm and 80 $\mu$m, respectively. Therefore, by using this technique, central length difference between the 2 gauge blocks up to 80 $\mu$m can be calibrated with the uncertainty due to non-linearity of 15 nm The experiment shows the large error of retrace closes to 0.15 $\mu$m at 250 $\mu$m. This can be determined the maximum difference in length to calibrate gauge blocks at difference nominal lengths. The measurement uncertainty of non-linearity is evaluated and it is close to 15 nm.

Speaker: Mr Samana Peingbangyang (National Institute of Metrology (Thailand))

SPC2017 ID2494385.pdf

SPC2017 ID2494385.pptx

178 A New Proficiency Testing (PT) Evaluation for Conformity Assessment of Roughness Measuring Instruments

Surface finishing is an important process for manufacturing industries. Precise surface roughness measurement is crucial as it has a direct effect on surface quality. In Thailand, the National Institute of Metrology of Thailand (NIMT) provides reference roughness standards and roughness measuring instruments. NIMT also conduct Proficiency Testing (PT), which is an important process for conformity assessment. PT assesses a laboratory's ability to perform a measurement and is one way to improve the measurement quality of laboratories. In this work, PT was conducted based on a portable roughness tester as a standard measuring instrument. There were seven calibration laboratories from Thailand that participated in the PT with a technical protocol that was designed by NIMT. The roughness tester was provided by NIMT. Two roughness standards with different roughness values (Ra $\leq$1 and Ra >1) were prepared by each calibration laboratory. The PT measurands were common roughness parameters such as Ra, Rz and Rsm. As the roughness measuring instrument is based on LVDTs, we propose here a new proficiency testing evaluation which involves the calibration of the measuring instrument in the PT evaluation procedure. The PT results, according to ISO/IEC 17043, shows that six out of the seven participating laboratories indicated satisfactory performance (|En| $\leq$ 1) where the measurement uncertainty was based on a 95% confidence level. The PT results and evaluation procedure for conformity assessment of the roughness measuring instrument are presented. Finally, measurement techniques to improve measurement quality are recommended.

Speaker: Dr Achaya Teppitaksak (National Institute of Metrology (Thailand))

179 Fabrication on Prototype of Depth Calibration Standard Machine for Elastomer Hardness Tester

The prototype of depth calibration standard machine was fabricated to calibrate the depth of indentation for elastomer hardness tester. According to ISO 18898, ASTM D2240 and ASTM D1415, the measurement of indentation depth by a measuring device comprising a length-measuring system shall be in reference with the pressure foot of the elastomer hardness tester. Nation Institute of Metrology (Thailand); NIMT develop the depth calibration standard which can measure the indentation depth with always reference at the surface level of pressure foot of the hardness tester at each hardness scale. The calibration of the prototype of depth calibration standard machine was performed to provide the accuracy of the measurement of the machine which can be a suitable standard machine for depth of indentation within 1 µm complied with the requirement of ISO and ASTM standard. Furthermore, the prototype of depth calibration standard machine was validated to another NIMT method, which used the two length-measuring systems. The comparison results between 2 methods showed in a good agreement within 2 µm.
Therefore, the NIMT prototype of depth calibration standard machine can be used as a depth calibration standard for elastomer hardness tester provided the required accuracy of measurement complied with ISO 18898, ASTM D2240 and ASTM D1415.

Speaker: Dr Kittisun Mongkolsuttirat

180 Capacitively Coupled Contactless Conductivity Detection (C4D) technique for flow cytometry application

Capacitively Coupled Contactless Conductivity Detection (C4D) technique for particle detection or flow cytometry has been increasingly interested. This detection technique in microfluidic system utilizes two electrodes, excitation and pick-up electrodes, which are not directly in contact with solution in microchannel. In this study, Particulate of different sizes suspended in DI water were performance and were used in testing the C4D flow cytometry detection. Computational simulation were also carried out to investigate how the detected signal changes with the present of the suspended particulate.

Speaker: Korkuson Masaen (Chiangmai University)

ThEP

ThEP meeting

10:45 Coffee break

A10: Astronomy II

Conveners: Dr Maneenate Wechakama (Kasetsart University), Dr Peera Pongkitiwanichakul (Mahidol University)

181 The physical and pulsational parameters of oEA star AS Eridani: results from ground based analysis

AS Eridani is a 2.664152 day, semi-detached Algol type binary system. Gamarova, Mkrtichian & Kusakin (2000) discovered a short-period 24 min pulsation in a primary mass-accreting component. The oscillation spectrum has been investigated by Mkrtichian et al. (2004), they suggested that AS Eri is a promising pulsating star for further detailed investigations.
We started a new campaign of observations of AS Eri in order to get accurate orbital and pulsational parameters. We carried out a 42-day long space photometric observational data of AS Eri with the Canadian MOST-space telescope. We also collected 66 nights of a follow-up ground-based observations of AS Eri with robotic telescopes PROMPT and 308 echelle spectra of AS Eri were acquired using the fiber fed Medium Resolution Echelle Spectrograph (MRES) at the 2.4meter Rithchey-Chretien Telescope of Thai National Observatory (TNO). Here we present results of the ground based observations of AS Eri. We used the Least Square Deconvolution (LSD) code to construct the LSD profiles and to measure the radial velocities of both components. The physical parameters of binary system were obtained from a simultaneous solution of the photometric and the radial velocity data using the PHOEBE code. We found an accurate parameters of the system and the low-amplitude pulsation spectrum.

Speaker: Ms Khemsinan Gunsriwiwat (Chiang Mai University)

182 High redshift Quasars selection with deep Optical & Near-IR photometry and Photo-z technique for EoR study

We present the technique for selecting high redshift quasar candidates, $z \approx 6 – 11$, suitable for studying the Epoch of Reionization (EoR). Such technique is important for deep and resource-intensive spectroscopic follow-up to confirm the final identification of the sources as well as studying the Inter Galactic Medium (IGM) and its environment. We employ deep optical and near-infrared photometry from the 3.6-m Canada-France-Hawaii Telescope (CFHT) and the European Southern Observatory (ESO) 4.1-m VISTA telescope, respectively. The reduced data and catalogues are taken from the CFHT Legacy Survey (CFHTLS) D2 field and the public UltraVISTA survey Ultra-Deep stripes which have significant overlap on the COSMOS field, i.e. around RA=10:00:28 DEC=02:12:30. The sample of candidates are also pre-selected to avoid spurious detection from artefacts induced by bright stars (J < 16). We then apply a Photometric redshift (Photo-z) analysis on the samples of optical dropout sources based on the g, r, i, z (CFHTLS) and Y, J, H, K (UltraVISTA) photometry. The final sample of high redshift quasar candidates in the Ultra-Deep stripes (total area $\approx 1$ deg$^2$) and their photo-z’s are then reported with their likelihood estimations.

Speaker: Mr Narenrit Thananusak

183 Squeezed bispectrum for multi-fields inflationaly model with constant metric in field space

We study non-Gaussianities in primordial perturbations by using the Delta-N approach to avoid the complexity of solving differential equations for non-linear perturbations directly. we have shown, for the case of the double massive inflation with the arbitrary constant metric in the field space, even the mass of two scalar fields are equal, the non-Gaussianity parameter may not vanish. Furthermore, for some appropriate forms of the field metric, we can get the large non-Gaussianity parameters for squeezed mode.

Speaker: Sakdithut Jitpienka (The Institute for Fundamental Study, Naresuan University)

184 Disformal coupling between dark energy and dark matter and the dynamics of the universe

We consider a cosmological model where the coupling between dark energy and dark matter is motivated by disformal transformation. We consider the case where conformal coefficient depends only on scalar field while disformal coefficient depends both on the scalar field and its kinetic energy. We found that there exist new two classes of fixed point when disformal coefficient depend on both scalar field and kinetic. These two classes of the fixed point can describe accelerated expansion of the universe at late time. The first class of the fixed points can exists only when the disformal coefficient depends on the kinetic of scalar field. The fixed point in the second class are able to be stable fixed point within the parameters ranges that correspond to the accelerated expansion of the universe. These fixed point can take two different values of the fixed point for the same values of the parameters of the model.

Speaker: Mr Stharporn Sapa

185 Camera technologies overview and Applications in Astronomy imaging

Andor is a global leader in the development and manufacturing of high performance scientific imaging cameras, spectroscopy solutions and microscopy systems to match your application needs in research and OEM.
The prsentation will brief introduce camera technologies, including Electron Multiplying CCD (EMCCD) cameras, Scientific CMOS (SCMOS) cameras, CCD cameras and Intensified cameras .We will also provide an overview of the key high-sensitivity, high-temporal-resolution detector technology types, used in astronomy applications such as adaptive optics wavefront sensing, solar exploration, high-time-resolution astrophysics, transit exoplanet discovery, gravitational lensing and even customized guide cameras. Furthermore, we will introduce Andor iKon-XL , the camera uniquely uses patent-pending ‘ColdSpace™’ technology to thermoelectrically cool a back-illuminated 16.8 Megapixel Very Large Area CCD sensor (e2v) down to -100 °C, circumventing the need for liquid nitrogen or cryo coolers. Extended Dynamic Range technology, facilitates lowest noise and maximum well depth within one scan, complemented by up to 18-bit digitization.

Speaker: Sean Chen (Andor Technology Ltd., 7 Millennium Way, Springvale Business Park, Belfast, BT12 7AL, United Kingdom )

A11: Instrument II

Conveners: Prof. Chatchawal Wongchoosuk (Kasetsart University), Prof. Wiwat Wongkokua (Kasetsart University)

186 Optimization parameters of installation automatic die bonding machine for integrated circuit packaging

In this paper, installation automatic die bonding machine and optimization parameters were studied in die attach process for integrated circuit (IC) packaging. Die attach process is one that is very important IC packaging manufacturing. This process is attaching a die or chip take to leadframe or substrate using die bonding machine. After installation machine, the parameters of equipment effect to performance of die attach process due to properties of die onto leadframe. For installation, the components of equipment were set up such as wafer table, stack loader, work holder, optical system, dispensing, and bond head before optimization parameters of die attach process. In experiment, the parameters of die bonding machine were optimized such as bond force, bond height, and bond time. The results showed that these parameters lead to optimize performance of die attach process that depend on properties of die bonding such as bond line thickness, fillet height, die tile, and die shear.

Speaker: Mr Tanatpol Nanthavittayaporn

187 The prototype of high stiffness load cell for Rockwell hardness testing machine calibration according to ISO 6508-2:2015.

The Rockwell hardness test penetrated depth normally not more than 0.260 mm. Using commercial load cell cannot achieve the force calibration proposed. For these reasons, the high stiffness load cell fabrication, HSL is subject. Its obviously advantage is deformed less than 0.020 mm at 150 kgf maximum load applied. The HSL prototype was designed in concept of direct compression then confirmed with finite element analysis, FEA. The results showed that it meet class 1 accuracy according to ISO 376:201. And maximum deformation lower than 0.012 mm at capacity. It is satisfactory to use for test force calibration of Rockwell hardness testing machine according to ISO 6508-2:2015[1] properly.

Keywords: Rockwell hardness testing machine, Test force calibration, High stiffness load cell.

Speaker: Dr Montree PAKKRATOKE (Metrologist)

SPC paper HSL-2017.pdf

SPC paper HSL-2017.pptx

188 The development of 1-D nest bar measurement system

The nest bar, or length bar, is a standard bar with two kinematic seats. The center-to-center length between seats is used as standard length for detecting geometric and thermal errors of an articulated arm coordinate measuring machine (Arm CMM) according to the guidance of ISO 10360-12:2016. Each seat shall be a kinematic seat where the center of the ball probe may be repeatedly positioned in the kinematic seats. A kinematic seat could also be a trihedral seat, conical seat or chamfered hole seat. Nowadays, a common technique for measuring the center-to-center distance is based on high accuracy CMM with 2-3 micrometer accuracy. In this paper, we introduce a new measurement method based on a combination of a 1-D length measuring machine and a He-Ne laser interferometer. The laser interferometer was aligned with the axis of a nest bar in order to eliminate the Abbe error from the measurement. A spherical probe was attached to 1-D machine’s arm to represent the center point of seats when the probe was seated. The distance of bar was measured when probe was placed in each kinematic seatsby laser interferometer with compensation of the refractive index of air. The system canbe measured the nest bar with sub-micrometer accuracy.

Speaker: Dr Narin Chantawong (National Institute of Metrology (Thailand))

189 Preliminary of spindle axial and angular motions measurement using plane mirror interferometer

The industrial processes for high-precision engineering and metrology require the fine quality control of products. The precision of rotary spindle is also required to enhance the accuracy of spindle motions to the nanometer and sub-µradian levels. Spindle measurements by conventional methods will have contributions from the spindle motion error and the form error of the target artifact. In the conventional methods to measure axial and angular motions, a complicated artifact is required. Small volume artifact is favorable from the viewpoint of the accurate and practical measurement. This paper describes a method of spindle axial and angular motions using plane mirror interferometer. In the method, the plane mirror is a reference artifact, and it is installed on top of the spindle of interest. Three optical sensors are fixed above the plane mirror to observe the proper positions of the mirror. The optical sensor consists of a laser as a light source, and an interferometer. The interferometer observes an interference fringe between a reflection light form a fixed mirror and a reflection light from the plane mirror for vertical displacement measurement. Using three optical sensors, three vertical displacements of the mirror can be measured. From these measured displacements, axial and angular motions of the mirror, i.e. the spindle, can be calculated concurrently. In the paper, a measurement principle, instrumentation and experimental results are discussed.

Speaker: Muhummad Madden (National Institute of Metrology, Thailand)

190 Design and Implementation of a Measurement System for Inspection of Magnetic Force Microscopy Probes

The development of a measurement system for non-destructive testing of magnetic force microscopy (MFM) probes is discussed in this paper. Typical MFM probes are characterized by equipped in a conventional atomic force microscope (AFM). Test parameters are the resonance frequency of MFM probes and its response to a magnetic stray field from a standard test sample. This procedure involves tapping a MFM probe across the surface of the test sample which sometimes can cause damage and wear on the test MFM probes. The operating principle of the implemented system is similar to that used in standard AFMs/MFMs. An optical beam deflection technique is used to measure the oscillation of MFM probes corresponding to driving frequencies. The system employs a solenoid coil as a source for generating the out-of-plane magnetic field. The profile of magnetic field intensity was characterized by a gauss meter. Several commercial available MFM probes with different coating materials and ones developed in-house were used as a test sample. Measurement results were also compared with a standard AFM/MFM machine.

Keywords: MFM tip inspection, non-destructive testing, NDT, AFM, MFM, magnetic probes

Speaker: Mr Natthawat Phanchat (Silpakorn University)

A9: Condensed Matter and Accelerators

Conveners: Prof. Pakpoom Reunchan (Kasetsart University), Dr Papichaya Chaisakul (Kasetsart University and Université Paris-Sud)

191 Extreme doping in complex oxides

Complex oxides host a wide variety of interesting physical properties, including charge localization in the form of small polarons, magnetism,ferroelectricity, giant magnetoresistance, and high-Tc superconductivity. In this presentation we discuss how doping can modify the properties of complex oxides, for instance by transforming a band insulator into a Mott insulator. We discuss results of first-principles calculations for the evolution of the electronic structure of complex-oxide heterostructures as a function of the thickness in quantum-well heterostructures. More specifically, we show how a two-dimensional electron gas becomes a Mott-insulator as the thickness of the quantum well is decreased. The onset of charge localization is analyzed in terms of electron density in octahedral distortions at the interface. We compare our results to available experimental results.

Speaker: Dr Anderson Janotti (University of Delaware)

192 Microanalysis study on ancient Wiangkalong Pottery

Wiangkalong is one of major ceramic production cities in northern of Thailand, once colonized by the ancient Lanna Kingdom (1290 A.D.). Ancient Wiangkalong potteries were produced with shapes and designs as similar as those of the Chinese Yuan and Ming Dynasties. Due to the complex nature of materials and objects, extremely sensitive, spatially resolved, multi-elemental and versatile analytical instruments using non-destructive and non-sampling methods to analyze theirs composition are need. In this work, micro-beam X-ray fluorescence spectroscopy based on synchrotron radiation was firstly used to characterize the elemental composition of the ancient Wiangkalon pottery. The results showed the variations in elemental composition of the body matrix, the glaze and the painting, such as K, Ca, Ti, V, Cr, Mn and Fe.

Speaker: Dr Pisutti Dararutana (Royal Thai Army Chemical Department)

193 Beam Dynamics Simulation of Photocathode RF Electron Gun at the PBP-CMU Linac Laboratory

Photocathode RF electron guns are widely used at many laboratories because of the high quality of the produced electron beams. By using a short-pulse laser to induce the photoemission process, the electrons are emitted with low energy spread. Moreover, the photocathode RF guns are not suffered from the electron backbombardment effect, which can cause the limited electron current density. In this study, we aim to develop the photocathode RF gun for the linac-based THz radiation source. The gun consists of a one and a half cell S-band RF cavities with a maximum electric field of about 60 MV/m at the full cell. We study the beam dynamics of electron traveling through the electromagnetic field inside the RF-gun by using the particle tracking program ASTRA. In addition, the laser and beam properties are optimized for low-emittance beam generation. The solenoid magnet is applied for beam focusing and emittance compensation. The proper solenoid magnet current is then investigated.

Speaker: Ms Khachiwan Buakor (Chiang Mai University)

194 Development of Linac-based MIR/THz Free-electron Laser Facility in Thailand

A linac-based MIR/THz free-electron laser facility is under the development at the Plasma and Beam Physics Research Facility, Chiang Mai University. The ultimate goal of the project is to generate the infrared radiation covering wavelengths from about 10 to 125 micron. The main applications of the radiation in this wavelength range involve MIR/THz imaging and spectroscopy. The future FEL facility will consists of an injector system, an experimental station for coherent transition radiation, two magnetic bunch compressors and two undulator magnets and their corresponding optical cavities for generation of MIR and THz FELs. The injector system combines an RF-gun, an alpha magnet, a travelling-wave linac structure and other associated components. The magnetic bunch compressors compress the electron bunches to have a bunch length in the ps regime with energy spread preservation. An expected electron beam energy is between 10 to 20 MeV. Two undulator magnets with maximum undulator parameters of 1 and 0.95 will be used for THz-FEL and MIR-FEL, respectively. In this paper, we present the status of the design and construction of this future FEL facility.

Speaker: Sakhorn Rimjaem (Chiang Mai University)

ThEP

ThEP meeting

12:15 Lunch

A12: High Energy Physics

Conveners: Prof. Auttakit Chatrabhuti, Sitthichai Pinkanjanarod (Department of Physics, Kasetsart University)

195 Supersymmetrizing a Quantum Mechanical System.

Supersymmetry (SUSY) is one of the most active fields of research in high-energy physics and particle physics. However, SUSY is not so easily accessible for students wishing to get started on this field of research due to complexities often associated with quantum field theories. In this talk, I'll discuss some aspects of SUSY in the context of quantum mechanics. In particular, I'll demonstrate how to supersymmetrize a familiar quantum system such as a harmonic oscillator and a square well.

Speaker: Patipan Uttayarat

196 Review of Proton Radius Puzzle

Our ability to completely understand the size of the proton has come into question. This puzzle is presently unsolved. It has been building up since 2010 when a measurement of the Lamb shift in muonic hydrogen yielded a very precise value$^1$ for the electric charge radius of the proton equal to $\langle$r$^2$$_E$$\rangle$$^{1/2}$ = 0.84087(39) fm with an amazing 0.1% uncertainty. This precision measurement, however, is 4% smaller than the accepted value$^2$ of the radius of the proton of $\langle$r$^2$$_E$$\rangle$$^{1/2}$ = 0 .8751(61) fm. This latter measurement has been the standard and determined from a combination of electron data either by scattering from protons or by analyzing the fine structure splitting in hydrogen energy spectra using the Lamb shift. This disagreement is significant and very important to reconcile, not only for our understanding of the structure of the proton, but also for understanding of the predictions of quantum electrodynamics. A short review of these measurements, recently published re-analysis$^3$ of old data, possible corrections, and selected new experiments will be presented to help solve the puzzle.

1. R. Pohl et al. Nature 466, 213–216 (2010), A. Antognini et al., Science 339, 417 (2013)
2. P.J. Mohr et al., Rev. Mod. Phys 84, 1527-1603(2012), CODATA 2010
3. D.B Higinbotham et al., Phys Rev C93, 055207(2016)

Speaker: Prof. Richard A. Lindgren (University of Virginia, Dept. of Physics, Charlottesville, VA, 22903,USA)

197 Inflation from Supergravity with Gauged R-symmetry in de Sitter Vacuum

We study the cosmology of a recent model of supersymmetry breaking,
in the presence of a tuneable positive cosmological constant, based on a
gauged shift symmetry of a string modulus that can be identified with
the string dilaton. The minimal spectrum of the ‘hidden’ supersymmetry
breaking sector consists then of a vector multiplet that gauges the shift
symmetry of the dilaton multiplet and when coupled to the MSSM leads
to a distinct low energy phenomenology depending on one parameter. Here
we study the question if this model can also lead to inflation by identifying
the dilaton with the inflaton. We find that this is possible if the Kahler
potential is modified by a term that has the form of NS5-brane instantons,
leading to an appropriate inflationary plateau around the maximum of
the scalar potential, depending on two extra parameters. This model is
consistent with present cosmological observations without modifying the
low energy particle phenomenology associated to the minimum of the scalar
potential.Talk based on hep-ph/1608.02121.

Speaker: Dr Rob Knoops (Chulalongkorn University, Bangkok)

198 Quantum criticality from Ising model on dynamical simplicial geometries

We argue the classical Ising model coupled to 2d dynamical simplicial geometries and show that even though the Ising model is classical, the Curie
temperature can reach the absolute zero by tuning a parameter
controlling simplicial geometries. This talk is based on a work in
progress with Tomo Tanaka in Rikkyo University, Japan.

Speaker: Dr Yuki Sato

199 Holographic non-Gaussianities in general single-field inflation

We use holographic techniques to compute inflationary non-Gaussianities for general single-field inflation, including models with a non-trivial sound speed. In this holographic approach, the inflationary dynamics is captured by a relevant deformation of the dual conformal field theory (CFT) in the UV, while the inflationary correlators are computed by conformal perturbation theory. In this paper, we discuss the effects of higher derivative operators, such as $(\partial_{\mu}\varphi\partial^{\mu}\varphi)^m$, which are known to induce a non-trivial sound speed and source potentially large non-Gaussianities. We compute the full inflationary bispectra from the deformed CFT correlators. We also discuss the squeezed limit of the bispectra from the viewpoint of operator product expansions. As is generic in the holographic description of inflation, our power spectrum is blue tilted in the UV region. We extend our bispectrum computation to the IR region by resumming the conformal perturbations to all orders. We provide a self-consistent setup which reproduces a red tilted power spectrum, as well as all possible bispectrum shapes in the slow-roll regime.

Speaker: Dr Hiroshi Isono (Chulalongkorn University)

200 Identification of top quark pair event from dileptonic decay channel by machine learning

To measure the properties of top quark, it is crucial to identify events containing top quark pair first by using discriminators. Currently cut-based discriminators are used to identify such events. This, however, may lead to inaccuracy due to the fact that cut-based discriminators might exclude collision events including top quark pair, or, even worse, include background events in which top quark pair is not present. Thus, we believe machine learning (ML) techniques can be applied to make a more sophisticated discriminator, which can lead to more accuracy on top quark pair identification. A discriminator with a purpose of classifying collision events into signal events including top quark pair and background events in dilepton channel has been developed based on ML techniques. In this project, available Monte-Carlo simulated datasets at CERN Open Data Portal, including signal ($t\bar{t}$ dilepton) and background (Drell-Yan, single top, and diboson), are used to train the discriminator with various ML techniques, such as Boosted Decision Tree, Support Vector Machine, etc. The performance of the discriminator after being trained with several ML techniques are then compared in this project, and are used to classify collision events from data collected by CMS in pp collisions at $\sqrt{s}$ = 7 TeV, also available from CERN Open Data Portal. The result of top quark mass reconstruction where ML-based discriminator is used are also compared to the result where cut-based discriminator is used.

Keywords: ttbar, dilepton channel, machine learning

Speaker: Vichayanun Wachirapusitanand

201 $\Lambda_{c}$ baryon production in effective Lagrangian approach

In the near future, experimental studies of charmed baryon productions will be carried out at $\bar{\text{P}}\text{ANDA}$ and J-PARC. In the $\bar{\text{P}}\text{ANDA}$ experiment, charmed baryon productions will be studied in proton-antiproton annihilation reactions. At J-PARC, the spectroscopy study of charmed baryons via the pion induced reactions at a high-momentum beam line will be investigated. Therefore, it is a great opportunity to perform a theoretical study of charmed baryon production reactions systematically while these experimental facilities are now under investigation. In this work, charmed baryon production reactions (for example, $p\bar{p} \to \Lambda_{c}\bar{\Lambda}_{c}$ reaction) will be investigated by using effective field theory. We start from the construction of the effective Lagrangian satisfying $SU(2)$ flavor symmetry, heavy-quark symmetry, and large-$N_{c}$ analysis. Then, cross sections of charmed baryon production reactions will be computed from the effective Lagrangian. Our predictions may be tested by the $\bar{\text{P}}\text{ANDA}$ and J-PARC facilities in the future.

Speaker: Mr Thanat Sangkhakrit (School of Physics, Institute of Science, Suranaree University of Technology)

A13: Material Physics

Conveners: Adisak Boonchun, Dr jiraroj T-thienprasert (Kasetsart University)

202 Mechanical and Electrical Properties of Fly Ash Geopolymer Composited with Short Carbon Fibre

Workability, compressive strength and electrical properties of high calcium (Class C) fly ash geopolymer composited with short carbon fibre (CF) were investigated. The liquid to ash (L/A) ratio was kept at 0.4, while the carbon fibre concentration, curing temperature and age of the specimens were varied. The fibre content was in a range of 0-0.5%CF. The curing temperature was 25°C and 60°C and the specimens were tested at the age of 7, 14 and 28 days. The workability of freshly mixed geopolymer paste was tested by miniature slump cone testing method. The workability decreased when higher content of CF was added. However, the compressive strength was improved and reached the maximum value of 31.3 MPa at 0.5%CF. I-V curve measurement and cyclic voltammetry (CV) techniques were used for electrical properties determination. The alternative current, with the maximum current of 100 mA, was applied to the specimens. It was found that the CF concentration significantly affected the electrical resistivity. The lowest resistivity was obtained with 0.5%CF addition. For 25°C curing, longer curing day led to the increase in electrical resistivity whereas it was almost unchanged for 60°C curing temperature. In the case of CV measurement, the measurement was carried out at 28 days age. The CV curves showed the dependence on curing temperature, CF content and scan rate. X-ray diffraction pattern and Fourier transform infrared spectra confirmed that CF addition did not change the chemical structure of the geopolymer.

Keyword: fly ash geopolymer; geopolymer composite; carbon fibre; electrical properties; mechanical properties

Speaker: Ms Panjasil Payakaniti (Khon Kaen University)

203 Giant dielectric properties with excellent temperaturestability of (Ga0.5Nb0.5)xTi1-xO2 ceramics

In this work, we investigate the giant dielectric properties of (Ga0.5Nb0.5)xTi1-xO2(where x=0.01, 0.025, 0.05 and 0.1) prepared by a solid state reaction method.The phase composition,microstructure,and oxidation statesare characterized by X-ray diffraction, field-emission scanning electron microscopy and X-ray photoelectron spectroscopy, respectively.The single phase of rutile-TiO2with dense microstructure are obtained in all sintered (Ga0.5Nb0.5)xTi1-xO2ceramics. The existence of Ti3+ and oxygen vacancies are confirmed. The dielectric constant increased with increasing co-doping (Ga+Nb)concentration. Excellent dielectric properties are obtained in the (Ga0.5Nb0.5)xTi1-xO2ceramic with x= 0.1 sintered at 1550oC for 1h.Low dielectric loss tangent (< 0.05) and very large dielectric constant (e = 41267) with excellent temperature coefficient (<15%) in the range of -70 to 170 oC are achieved. The giant dielectric response over a broad temperature range of the (Ga0.5Nb0.5)xTi1-xO2ceramics is primarily attributed to the interfacial polarization at internal insulating interfaces.

Keyword: TiO2, Giant dielectric permittivity, Temperature coefficient, Electron-pinned defect-dipole.

Speaker: Mr Wattana Tuichai (KhonKaen University)

204 Fabrication and Properties of polyacrylic acid by ionic surfactant disturbance method

The formation of polymeric materials can be achieved by several methods such as melting and casting, screw extrusion, cross-linking of resin or rubber in a mold, and so on. In this work, the polyacrylic acid is formed by using the emulsion disturbance method. Despite extensively used in the colour painting and coating industries, acrylic emulsion can be processed into a foam and powder configuration by a reaction between acrylic emulsion and salt. The solidification hardly changes the volume between liquid emulsion and solidified polymer which means the final structure of polyacrylic acid is filled with opened air cells. The opened air cell structure is confirmed by the result from scanning electron microscopy. The chemical analysis and crystallography of acrylic powder and foam are examined by Fourier-transform infrared spectroscopy and X-ray diffraction respectively. The phase transformation and stabilization are studied by differential scanning calorimetry and thermo gravimetric analysis. Moreover, the mechanical properties of acrylic foam were observed by tensile, compressive and hardness test. In addition to the basic property analysis, acrylic foam was also used in the particle filtration application.

Speaker: Suriya Lawan (Mahidol University)

205 Effects of Co‒Doping on Dielectric and Electrical Responses of CaCu$_3$Ti$_4$$_-$$_x$(Nb$_1$$_/$$_2$In$_1$$_/$$_2$)$_x$O$_1$$_2$ Ceramics

In this work, CaCu$_3$Ti$_4$$_-$$_x$(Nb$_1$$_/$$_2$In$_1$$_/$$_2$)$_x$O$_1$$_2$ ceramics with x = 0, 0.025, 0.05, 0.10, and 0.20 were prepared by a conventional solid state reaction method. Changes in crystal structure, microstructure, dielectric, and electrical properties were systematically investigated. The main phase of CaCu$_3$Ti$_4$O$_1$$_2$ ceramic was clearly observed in all the samples. The average grain size of CaCu$_3$Ti$_4$O$_1$$_2$ decreased by (Nb$^5$$^+$+In$^3$$^+$) doping. The dielectric permittivity of CaCu$_3$Ti$_4$$_-$$_x$(Nb$_1$$_/$$_2$In$_1$$_/$$_2$)$_x$O$_1$$_2$ ceramics was slightly dependent on frequency as co-doping concentration increased, which was due to a decrease in grain size. Dielectric behavior can be well described by the internal barrier layer capacitor (IBLC) model based on the interfacial polarization at grain boundaries. By using an impedance spectroscopy analysis at various temperatures, it was found that the grain boundary resistance and potential barrier height at the grain boundary of CaCu$_3$Ti$_4$O$_1$$_2$ were reduced by co‒doping with (Nb$^5$$^+$+In$^3$$^+$) ions, resulting in an enhancement of dc conductivity and the related dielectric loss tangent.

Speaker: Mr Jakkree Boonlakhorn (Khon Kaen University)

206 Characterization and Electrochemical Properties of Cu$_2$P$_2$O$_7$ Nanoparticles Prepared by Hydrothermal Method

Copper phosphate (Cu$_2$P$_2$O$_7$) nanostructures were synthesized by hydrothermal method. The precursor products were calcined at 500, 600 and 700 oC in air for 3 h. Thermogravimetric/differential thermal analysis (TG/DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) were used to study the phase formation, crystalline structure, morphology and functional group of samples. Electrochemical properties were measured by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD). XRD analysis confirms a monoclinic crystal structure of Cu$_2$P$_2$O$_7$ with space group C2/c. SEM micrographs of calcined samples show a fused grain structure for smaller crystals with more porous and rough surfaces. The CV results show the redox peaks in all curves, exhibiting reversible electron-transfer for Faradaic redox reactions with the largest CV areas for sample calcined at 600°C. The Cu$_2$P$_2$O$_7$ positive electrodes show a maximum high specific capacitance. In addition, the result of the electron-active sites participated in the Faradaic redox reaction indicat a valence interchange or charge hopping of cations

Speaker: Mr Attaphol Karaphun (Khon Kaen University)

207 Hydrothermal synthesis and characterization of hyperbranched BiVO$_4$ microstructure and its applications

Bismuth vanadate (BiVO$_4$) microstructures were successfully synthesized by a hydrothermal method at 200 °c for 24 h. The phases and morphologies of the products were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and photoluminescence (PL) spectroscopy. BiVO$_4$ microstructures were self-assembled from bismuth nitrate and ammonium vanadate solutions by controlling pH of the precursor solutions without adding surfactant. The XRD results show that the products were pure monoclinic BiVO$_4$ phase at the pH 1. At pH 1 and 2, the morphologies of the products were hyperbranched and spherical microstructure, respectively. The PL spectra were determined by an excitation wavelength of 275 nm. They showed the similar peaks at 420 nm (2.95 eV) and 365 nm (3.40 eV) for those of the products synthesized at the pH 1-2. In addition, the anti-bacterial properties of the as-synthesized BiVO$_4$ were investigated. The result shows that BiVO$_4$ synthesized at the pH 1 can play the role in inhibiting of S. aureus (3.5×10-5 CFU) more than E. Coli (a large number of counts).

Speaker: Dr Nuengruethai Ekthammathat (Program of Chemistry, Faculty of Science and Technology, Bansomdejchaopraya Rajabhat University)

A14: Environment

Conveners: Prof. Weeraphat Pon-on (Department of Physics, Kasetsart University), Prof. Chatchawal Wongchoosuk (Kasetsart University)

208 effect of chemical composite, puffing temperature and moisture content on physical properties of puffed apple and potato

Puffing technique is the process that can improve physical properties of fruit and vegetable. However, the effect of chemical composite in foods on puffing characteristics is still lack of study. Therefore, potato and apple slices were comparative study on physical properties. Potato and apple were sliced into 2.5 mm thickness and 2.5 cm in diameter. Potato slices were treated by hot water blanching for 2 min while apple slices was not treatment. After that, they were dried in 3 steps. First step, they were dried by hot air at temperature of 90C until their moisture content reached to 30, 40, and 50 % dry basis. Then they were puffed by hot air at temperature of 130, 150, and 170C for 2 min. Finally, they were dried again by hot air at temperature of 90C until their final moisture content reached to 4% dry basis. The experimental results showed that chemical composite of food affected on physical properties of puffed product. Puffed potato had higher volume ratio than those puffed apple because potato slices contains starch that could be generated sealed surface layer and therefore it potentially escape vapor during puffing. The higher starch content provided more hard texture and higher initial slope of potato than those apple. Puffing temperature and moisture content strongly affected on color, volume ratio, and textural properties of puffed potato slices. Increasing of puffing temperature and intermediate moisture content induced higher volume ratio and then lower hard texture. In addition, increasing of puffing temperature and moisture content provided higher drying rate of puffed product.

Speaker: Mr Surapit Tabtiang

209 Observation of Cosmic Ray Variation with Atmospheric Water Vapor at Doi Inthanon

Neutron monitor (NM) and Bare (lead-free) neutron counters are ground-based detectors to detect the variation of intensity in cosmic rays. In addition, the bare detector to neutron monitor count rate ratio (Bare/NM) provides information on the cosmic ray spectrum. In the present work, we utilized data from the Princess Sirindhorn Neutron Monitor station at Doi Inthanon, Thailand, with the world’s highest cutoff rigidity of 16.8 GV to observe variations in cosmic rays with time. We also found that variation in Bare/NM is strongly anti-correlated with surface atmospheric water vapor (Ew), with a nonlinear relationship.The water vapor pressure data can be inferred from the Global atmospheric Data Assimilation System (GDAS) and Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2). From these database we derive precipitable water vapor (PWV), i.e., the column density of water throughout the atmosphere. The results of comparison of PWV from the two database, from balloon data, and from GPS detectors in Chiang Mai Province will be discussed, and we will examine whether the Bare/NM count rate ratio at Doi Inthanon has a more linear relationship with PWV.

Speaker: Pradiphat Muangha (Mahidol University)

210 Non-chemistry coupled PM10 modeling in Chiang Mai City, Northern Thailand: A fast operational approach for aerosol forecasts

An optimum cumulus parameterization scheme was determined for the Weather Research and Forecasting (WRF) model for Northern Thailand. This was then applied to model PM10 data in Chiang Mai city for 10-days during a high haze event using an updated WRF version (v. 3.7) and updated land use categories from the Moderate Resolution Imaging Spectroradiometer (MODIS). A higher resolution meteorological lateral boundary condition (from 1 degree to 0.25 degree) was also used from the NCEP GDAS/FNL Global Tropospheric Analyses and Forecast Grid system. A 3-category urban canopy model was also added and the Thompson aerosol-aware microphysics parameterization scheme was used to model the aerosol number concentrations that were later converted to PM10 concentrations. Aerosol number concentration monthly climatology was firstly used as initial and lateral boundary conditions to model PM10. However, this could not capture the variability, underestimated the high PM10 spikes and overestimated low PM10 values (R = 0.29) during the period studied when compared to surface data obtained from the Pollution Control Department (PCD). The authors then added satellite data to the aerosol climatology that improved the comparison with observations (R = 0.45). The authors then tried to use the ERA-Interim meteorological lateral boundary conditions to model the PM10. This captured the variability better (R = 0.4830) and the low PM10 concentrations. However, this setup underestimated the high PM10 spikes. In all cases, the simulations were not able to model one high PM10 spike. This is due to a local emission source that the meteorology, aerosol climatology and satellite data failed to pick up as proven by adding a hypothetical source upstream of the measurement site.

Speaker: Dr Ronald Macatangay (National Astronomical Research Institute of Thailand)

211 Drying of paddy rice by using two series of screw conveyor dryer

Two series screw conveyor dryer potentially dries agricultural product especially paddy rice. However, the effect of screw speed, drying temperature and drying cycle on decreased moisture content and energy efficiency is non-previous literatures. In this study, the paddy rice was carried into dryer at 4.8 kg/batch under screw speed 35, 50 and 75 rpm and drying temperature of 50, 70 and 90°C. The results showed that drying temperature and screw speed affected on decreased moisture content and specific energy consumption (SEC). Increasing of drying temperature provided higher amount of moisture content loss. However, the lower screw speed could be increased amount of moisture content loss because lower screw speed increased retention time of paddy rice in drying chamber. In addition, the amount of moisture content loss in the first drying cycle had higher than those second drying cycle then the first drying cycle had higher SEC than second cycle. In addition, the SEC decreased as lower drying temperature and lower crew speed.

Speaker: Mr Aswin Yodruk

212 Comparison of spectral ultraviolet irradiance measured from ground-based and satellite instruments at Nakhon Pathom province

In this study, comparison of spectral ultraviolet irradiance at 305, 310, 324 and 380 nm at satellite overpass time retrieved from OMI/AURA satellite with that from ground-based measurement was performed at Nakhon Pathom (13.82 N, 100.04 E), Thailand. The analyzed data period comprises from 1 January 2010 to 31 December 2015. The comparison results clearly show the overestimation of satellite data with root mean square difference (RMSD) between 22.9 and 48.9% and mean bias difference (MBD) between 5.3 and 39.8% for all sky conditions, and reduce to 10.6-40.5% and 0.18-34.9% for clear sky conditions. Further results show that the differences between the two data sets depend on atmospheric aerosol loads and clouds.

Speaker: Ms Juthatip Sriwongsa (Laboratory of Tropical Atmospheric Physics, Department of Physics, Faculty of Science, Silpakorn University)

213 An investigation of cloud base height in Chiang Mai

Clouds play very important role in the variation of surface solar radiation and rain formation. To understand this role, it is necessary to know the physical and geometrical of properties of cloud. However, clouds vary with location and time, which lead to a difficulty to obtain their properties. In this work, a ceilometer was installed at a station of the Royal Rainmaking and Agricultural Aviation Department in Chiang Mai (17.80 N, 98.43 E) in order to measure cloud base height. The cloud base height data from this instrument were compared with those obtained from LiDAR, a more sophisticated instrument installed at the same site. It was found that the cloud base height from both instruments were in reasonable agreement, with root mean square difference (RMSD) and mean bias difference (MBD) of 19.21% and 1.58%, respectively. Afterward, a six-month period (August, 2016-January, 2017) of data from the ceilometer was analyzed. The results show that mean cloud base height during this period is 1.5 km, meaning that most clouds are in the category of low-level cloud.

Speaker: Ms Sahussa Peengam (Laboratory of Tropical Atmospheric Physics, Department of Physics, Faculty of Science, Silpakorn University)

ThEP

ThEP meeting

15:05 Coffee break

A15: Atomics

Conveners: Sutee Boonchui (Department of Physics, Kasetsart University), Bumned Soodchomshom

214 Generation of spiral waves pinned to obstacles in a simulated excitable system

The dynamics of pinned spiral waves, whose tips trace the boundary of obstacles, are of interest due to the impact on human health. In heart, such pinned waves cause longer lifetime tachycardia. In this article, we present two methods for generating pinned spiral waves in a simulated excitable system. In method A, an obstacle is set in the system prior to an ignition of a spiral wave. This method may be suitable only for the case of large obstacles since it often fails when used for small obstacles. In Method B, a spiral wave is generated before an obstacle is placed at the spiral tip. With this method, a pinned spiral wave is always obtained, regardless the obstacle size. We demonstrate that after a transient the dynamics of the pinned spiral waves generated by the methods A and B are identical. Pinned spiral waves in both two- and three-dimensional systems are illustrated.

Speaker: Ms Metinee Phantu (department of physics, Kasetsart university)

215 Effect of a modified sinusoidal forcing on spiral waves in a simulated reaction-diffusion system.

Spiral waves are often found in excitable media and they are abnormal forms of action potential propagation in the case of hearts. Under an external forcing, the spiral waves drift and are subsequently terminated at the boundary. Spiral waves can be studied in simulations using a discrete reaction-diffusion system, thereby the time step must be less than a numerical stability limit (ts). In this article, we present the dynamics of spiral waves in a simulated system under an external forcing as a modified sinusoidal function of time. An optimization of the time step provides the optimal time step of 0.2ts. The spiral waves under the sinusoidal forcing drift along a straight line with a velocity independent on the forcing period. In addition, these spiral waves drift faster than those under a constant forcing with a magnitude equal to the root-mean-square value of the time-varying forcing.

Speaker: Ms Kritsana Khaothong

216 Investigation of transmission properties of a simple quantum Tesla valve

We investigate theoretically the transmission properties of a single atom passing through simple Tesla valve structures operated in a quantum mechanical regime. Our simple structure were made up of a few static equiangular triangles that allow a high and low transmission efficiency in one direction and not the other. Our best value of the extinction ratio, the ratio between forward and backward transmission, of the quantum valve exceeded 50. The variation of extinction ratio in both classical and quantum regime were compared and discussed over changes in geometrical arrangement inside the valve.

Speakers: Mr Jirayu Mongkolkiattichai, Mr Sorawich Maichum

217 Ab initio study on the effect of phenyl substitution on the binding of carbon dioxide to salcomine

Metal-organic complexes, such as metal-porphyrins, can function as homogeneous catalysts for electrochemical reduction. In this work we present ab initio electronic structure calculations for a reaction involving carbon dioxide and salcomine, a coordination complex consisting of a salen ligand and a cobalt (II) atom. Changes to the binding energy due to substitutions on the phenyl ring by different functional groups are also studied. Cases where a shrinking HOMO-LUMO gap decreases the overpotential and increases the catalytic efficiency of the complex are analyzed. This study provides a theoretical basis for possible salen complex candidates as electrocatalyst for the reduction of carbon dioxide.

Speaker: Mr Meliton Chiong III (Materials Science and Engineering Program, College of Science, University of the Philippines, Diliman, Quezon City, Philippines)

218 Molecular dynamics study of the elastic properties of copper-silver alloys using embedded atom model potentials

The elastic properties of copper-silver alloy were determined for different atomic compositions by molecular dynamics simulations using an embedded atom model (EAM) potential. The elastic constants (c$_{11}$, c$_{12}$, c$_{44}$) that describe the Young’s modulus, bulk modulus, and shear modulus, were obtained from the stress-strain curves using strains applied at a constant rate. The temperature dependence of the elastic properties from 300K to 600K is also reported.

Speaker: Mr Jan Fronimarc Viloria (National Institute of Physics, University of the Philippines Diliman, Quezon City)

219 Ionic effects on the DNA denaturation and DNA unzipping

The double-stranded DNA (dsDNA) that is separated and unwound changes its structure to the single-stranded DNA (ssDNA) in response either to the thermal energy or to the external forces. For the former the thermally induced dsDNA-to-ssDNA transition, called DNA denaturation, occurs in the polymer chain reactions. For the latter the force induced dsDNA-to-ssDNA transition, called DNA unzipping, separates two strands and opens a room for RNA polymerase to transcribe the sequence of base pairs. In DNA denaturation increasing the temperature higher than melting temperature, $T > T_{m}$, results in ssDNA. In DNA unzipping pulling the strands with the force stronger than critical force, $F > F_{c}$, also results in ssDNA. In the temperature-force phase diagram the critical force $F_{c}(T)$ is a boundary between the low temperature, small force phase of dsDNA and the high temperature, large force phase of ssDNA. The Na$^{+}$ concentration dependence of $T_{m}$ and $F_{c}(T)$ is studied by using the correspondence between the statistical mechanics and the time imaginary quantum mechanics. In the language of quantum mechanics the ssDNA emerges naturally as a delocalized state. Both melting temperature $T_{m}$ and critical force $F_{c}(T)$ are found to rise with increasing the Na$^{+}$ concentration in qualitative agreement with the calorimetric experiments measuring $T_{m}$ and the single molecule experiments measuring $F_{c}$. The enhancement of DNA stability in the presence of Na$^{+}$ ions establishes a notion of the electrostatic stiffening.

Speaker: Dr Sitichoke Amnuanpol (Physics department, Thammasat University)

A16: Magnetic and Semiconductor

Conveners: Adisak Boonchun, Dr jiraroj T-thienprasert (Kasetsart University)

220 Structural characterization of ferroic materials by advanced spectroscopy techniques

The Synchrotron-based X-Ray Absorption Near-edge Spectroscopy (XANES) and Polarized Neutron Reflectivity (PNR) techniques were employed to investigate the structural properties of BiFe$_{1-x}$Mn$_{x}$O$_{3}$ ceramic and Co/CoO/Au multilayer, especially to study the local structure of Mn in BiFe$_{1-x}$Mn$_{x}$O$_{3}$ ceramic and to verify the formation of secondary phase in Co/CoO/Au multilayer. Theoretical XANES spectra calculations corroborate with the interpretation of the XANES experimental data. In addition, the Co/CoO/Au multilayer was examined to explore the degree of recovery of the untrained state after the first two field cycles. Such a recovery was expected by field cycling a reorientation field ($H_{RE }$) along a direction of orientation angle ($\Omega_{RE }$) away from the initial field cooling direction. Measurements as a function of $\Omega_{RE }$ and the strength of $H_{RE }$ (along each direction) map the influence of $\Omega_{RE }$ on the reversal mechanism in the layers and thereby the degree of recovery.

Speaker: Prof. Rattikorn Yimnirun (School of Physics, Institute of Science and NANOTEC-SUT Center of Excellence on Advanced Functional Nanomaterials Suranaree University of Technology, Nakhon Ratchasima 30000, Thailand)

221 Magnetic properties of RF-sputtered Co71Pd29 Film on Underlayers

RF-sputtered Co71Pd29 film with the thickness of 117 nm was deposited on glass and on Al, Co, Cr and Ni under-layers. Magnetic and electrical properties were measured by VSM and 4-point probe techniques. All prepared Co-Pd film showed ferromagnetic phase at room temperature. The Magnetic anisotropy of all films excluding on Ni under-layer tended to normal to film plane. The parallel magnetic sqaureness of 0.33, 0.26, 0.27, 0.34 and 0.4 was found in the film on Al, Co, Cr and Ni under-layers and on glass, respectively. The highest perpendicular magnetic squareness of about 0.52 was observed on the Co-Pd film on Cr under-layer whereas the lowest magnetic squarenss of about 0.18 was found in the film on Co under-layer. The electrical resistance of about 30, 20, 13, 45 and 35 Ω was found in the film on Al, Co, Cr and Ni under-layers and on glass, respectively. The results indicated that magnetic squareness tended to enhance whereas electrical resistance was decreased by under-layer insertion.

Speaker: Ms Suthasinee Somboonsap

222 Response of Magnetic Force Microscopy Probes under AC Magnetic Field

In this paper, magnetic force microscopy (MFM) probes with different coating materials were characterized under AC magnetic field. A perpendicular magnetic write head similar to those used in hard disk drives was employed as the AC magnetic field generator. In order to measure a response of MFM probes to AC magnetic field, a MFM probe under test was scanned, at a scan height of 10 nm, across the surface of the magnetic write head. During MFM imaging, the write head was biased by a sufficient magnitude of AC current, approximately 30 mA. A spectral analysis for a frequency sweep from 1 kHz to 100 MHz was extracted from post-processing MFM images. As expected, a MFM probe coated with hard magnetic alloys, i.e. FePt, has the lowest response to AC magnetic fields. MFM probes coated with soft magnetic alloys, i.e. NiFe and NiCoCr, have a relatively high and flat response across the frequency range. In addition, CoCr, NiCo and pure Ni coated MFM probes show lower response than NiFe and NiCoCr probes at low frequencies; however, theirs response to AC magnetic field increase for the AC magnetic field with a frequency above 50 kHz. This can be implied that those MFM probes are a good candidate for being used to study the high-frequency performance of perpendicular magnetic write heads. Noting that response of all MFM probes significantly decreased when driven frequencies above 1 MHz due to the limitation of the hardware, i.e. response of quadrant photodiode and op-amp in a pre-amplifier.

Keywords: MFM tips, MFM, magnetic write heads, frequency response

Speaker: Ms Adiwan Sungthong (Silpakorn University)

223 Magnetic Force Microscopy Characterization of Perpendicular Magnetic Writers with Wrap-around Shield

Magnetic force microscopy (MFM) was employed to characterize the magnetic field distribution of two different designs of perpendicular magnetic writers with fully wrap-around shield (WAS). Typical magnetic write heads, located on a slider at the so-called air bearing surface (ABS), are composed of a magnetic write pole and a magnetic return pole. The write pole has a much small cross section area at the ABS than the return pole which is connected to magnetic shield. The write pole and the shield are separated by a non-magnetic gap layer. The shield structure is designed in such a way that it can confine the magnetic fields without significantly degrading field strength. In this work, MFM imaging was used to investigate the relationship between the gap structure and magnetic field strength/gradient. Magnetic field distributions of two different head designs were compared and discussed in detail. Experimental results revealed that the magnetic field intensity is linearly proportional to pole dimensions, especially the pole width. The field gradient, however, is dependent on not only spacing gap between shields and the write pole, but also the pole widths and thicknesses

Keywords: magnetic field gradient, perpendicular magnetic recording heads, phase contrast MFM

Speaker: Ms butsaporn saelim (Silpakorn University)

224 Structural, optical, electronic and magnetic properties of Fe-doped ZnO nanoparticles synthesized by combustion method and first-principles calculation

In this work, Zn$_1$$_-$$_x$Fe$_x$O (x=0.000, 0.0625 and 0.125) materials have been investigated in both experimental and theoretical aspects. The pure and Fe-doped ZnO nanoparticles were prepared by a combustion method. The crystal structures were characterized using the X-ray diffraction (XRD), morphology by the transmission electron microscopy (TEM) techniques, magnetic behavior by vibrating sample magnetometer (VSM), and optical band gap by ultraviolet-visible (UV-Vis) spectroscopy. In first-principles calculation, density of states (DOS) and electronic band structure of the Zn$_1$$_-$$_x$Fe$_x$O supercell have been calculated using general gradient approximation with Hubbard model scheme (GGA+U), packaged in the Vienna Ab initio Simulation Package (VASP). The calculation was performed using self-consistent projected augmented plane wave (PAW). From the study, the prepared nanoparticles of pure ZnO and 6.25 and 12.5% by mole of Fe-doped ZnO show different magnetic behavior from diamagnetism of ZnO. In the presence of the calculation results, the density of states of dopant systems shows state difference of spin up and spin down electron also an intermediate band, induced by d orbital of iron atoms, located near the valence band is observed. From these, it’s interesting that small amount of iron doping can engineer the band structure, and induce both intermediate band and magnetism in nonmagnetic ZnO material.

Speaker: Ms Pornsawan Sikam (Khon Kaen university)

A17: Statistical and Theoretical Physics

Conveners: Prof. Surasak Chiangga (Department of Physics, Kasetsart University), Dr Papichaya Chaisakul (Kasetsart University and Université Paris-Sud)

225 Applications of Fokker-Planck equations in liquid crystal physics and quantum optics

Fokker-Planck equations are partial differential equations that describe stochastic processes. Two applications will be discussed: liquid crystal physics and quantum optics. Liquid crystals can show different aggregate phases that can be used in commercial applications. These phases are self-organized equilibrium states and are characterized by order parameters such as the Maier-Saupe order parameter for nematic crystals. Using mean field theory, it is shown how the Fokker-Planck equation formalism can capture the self-organization character and the emergence of an order parameter. In the second application, it is illustrated how quantum optical systems can be described in terms of stochastic processes defined by Fokker-Planck equations. In this context, the quantum mechanical expectation values become expectation values of ordinary stochastic processes and can conveniently be determined by means of numerical simulations.

Speaker: Till Daniel Frank (University of Connecticut, USA)

226 Role of Mutual Information in Discrete and Continuous Time Markov Chains

There are some limitations of discrete-time Markov processes modeled as approximations to continuous-time Markov processes. In discrete-time simulation models, time is discretised into uniform steps and transitions between states are discribed by transition probabilities whereas, in continuous-time Markov processes, state changes are driven by transition rates. In our research, we focus on adaptive epidemic networks which consist of two main processes, i.e., infection and rewiring. Mutual information is used to quantify how correlate these two epidemic processes are to one another. We observe the similarities and discrepancies of discrete-time and continuouse-time via computer simulations, and show how discretisation of time affects mutual information.

Speaker: Ms Suwakan Piankoranee (Department of Physics, Faculty of Science, Chulalongkorn University)

227 On the discrete-time two coupled harmonics oscillators

We take an assumption about the time variable in physics that actually the continuous time flow constitutes from in finite tiny discrete time steps resulting in different behavior of the system between these two time scales. To proof the assumption, the two coupled harmonic oscillators is studied as a toy model both in classical and quantum realms. In classical level, the discrete equation of motion is obtained as a discrete mapping. Under the continuum limit, a standard equation of motion is retrieved. In quantum level, the discrete wave function is obtained and interestingly the probability distribution is a bit broader than the usual one. Furthermore, the uncertainty principle in discrete-time case is modified by an extra-term containing a discrete-time parameter. Entanglement of the system is also studied by using the linear entropy in this discrete-time scale. The result shows that entanglement between two particles depends on the size of the discrete-time step and the coupling constant. As expected, the standard entanglement behavior is recovered under the continuum limit. We find that the system evolves differently in discrete-time scale comparing to the continuous-time scale.

Speakers: Dr Sikarin Yoo-kong (King Mongkut's University of Technology Thonburi ), Mr Watcharanon Kantayasakun (Department of physics , King Mongkut's University of Technology Thonburi )

228 Kinetic Monte Carlo simulations of uniform islands on flat and pillar-like substrates in heteroepitaxial thin film growth

The fabrication of uniform island nanostructures on heteroepitaxial thin films is a crucial step toward improving the efficiency of optoelectronic and solar cell devices. In this work, we investigate a strained heteroepitaxial thin film system in two dimensions using the kinetic Monte Carlo simulation method. The strain arising from the lattice mismatch is incorporated into the system using an atomistic ball-spring model. Films are grown onto flat and pillar-like substrates. For films on a flat substrate, growth condition dependence of film surface morphology, critical thickness, and island size is presented. For films on pillar-like substrates, uniformity of islands is investigated as a function of patterned substrate parameters. In contrast to the flat substrate, pillar-like substrates provide preferred sites for island formation and enhance island size uniformity. We found three types of island configurations with regular islands located on the top of filled windows, on the top of pillars, and at the bottom of windows. An island configuration diagram as a function of patterned substrate parameters is shown.

Speaker: Dr Manit Klawtanong (Department of Physics, Faculty of Science, Chulalongkorn University)

229 Born approximation in linear-time invariant system

Linear-time invariant (LTI) oscillation systems such as mechanical vibration,
series RLC and parallel RLC circuits under external driving force can be solved by using simplest initial conditions or
employing of Green's function of which knowledge of initial condition
of the driving force term is needed. Here we show a mathematical connection of the LTI system and the Helmholtz equation.
Time-independent Schr\"{o}dinger equation in quantum mechanical scattering problem, as in undergraduate physics course, can be written in form of the Helmholtz equation.
We apply Born approximation used in quantum mechanics
to obtain LTI general solution in form of infinite Born series which can be expressed as a series of one-dimensional Feynman graphs.
Conditions corresponding to the Born approximation and slow-roll approximation are given for the case of harmonic driving force.
We show that by transforming the second-order LTI system into Helmholtz equation, the Born-approximated general solution can be found
(at least to first order approximation) for any form of driving force, given the driving force initial value.

Speaker: Dr Burin Gumjudpai (IF Naresuan University)

230 An advantage of greater diversity

We find greater genetic diversity in a Penna model when the mutation threshold is less than the reproductive age, for the case of individuals reproducing only once in their lifetime. This greater diversity is obtained at the cost of decreased saturation population. An increased mean lifespan was obtained for the population with greater genetic diversity. We interpret this longer lifespan as a benefit that supports the idea that it is better to have greater genetic diversity.

Speaker: Mr Amancio II Manceras (University of the Philippines Diliman)

ThEP

ThEP meeting

Poster Presentation II

231 Determining the Relationship of Atmospheric CO2 Concentrations to Vehicular Traffic

This research aims to investigate the relationship between atmospheric carbon dioxide (CO2) concentrations, traffic count, vehicle type and meteorology at three study sites in Amphoe Muang Lampang in Thailand. Initial measurements were conducted since December 2016 from 2:00-4:00 PM. Since CO2 concentrations also depend on biospheric processes (photosynthesis and respiration), the chosen measurement time period corresponded to stable CO2 concentrations with a minimum amount of variability. This ensured that the measured CO2 concentrations primarily come from traffic. Multiple regression analysis will then be utilized to determine which factors contribute significantly to the measured CO2 emissions.

Speakers: Ms Laksika Chumphuin (Lampang Rajabhat University), Ms Suthima Fankrea (Lampang Rajabhat University)

232 Low Temperature Reduction of Graphene Oxide by Plasma Processes

Graphene oxide (GO) is graphene sheet laced with oxygen-containing functional groups that located at edge of the lattice. The properties of GO can be modified depending on the degree of reduction of oxygen-containing functional groups. Typical methods to reduce GO include wet chemical processes and thermal annealing in which hazardous chemical substances and high temperature are applied. In this work, plasma processes are conducted to reduce GO. GO films on silicon substrates are exposed to argon plasma generated by a radio frequency (RF) discharge. By superimposing pulsed negative voltage at 5 kV to the substrate holder, argon ions in the plasma can be accelerated to interact with GO. The duty cycle of the pulse will be varied therefore GO samples undergo plasma treatment and ion implantation alternately. Changes in atomic compositions and structure are analyzed using X-ray photoelectron spectroscopy, atomic force microscope and Raman spectroscopy. Reduced GO can be obtained with a hybrid process at low temperature.

Speaker: Mr Krisada Soonthornnant (Department of Physics and Materials Science Faculty of Science, Chiangmai University Chiangmai, Thailand)

233 Spectroscopic properties for identifying sapphire samples from Ban Bo Kaew, Phrae Province, Thailand

Gemstone commercial is a high revenue for Thailand especially ruby and sapphire. Moreover, Phrae is a potential gem field located at the northern part of Thailand. The studies of spectroscopic properties are mainly to identify gemstone using advanced techniques (e.g. UV-Vis-NIR spectroscopy, FTIR spectroscopy and Raman spectroscopy). Typically, UV-Vis-NIR spectroscopy is a technique to study the cause of color in gemstones. FTIR spectroscopy is a technique to study the functional groups in gem-materials. Raman pattern can be applied to identify the mineral inclusions in gemstones. In this study, the natural sapphires from Ban Bo Kaew were divided into two groups based on colors including blue and green. The samples were analyzed by UV-Vis-NIR spectrometer, FTIR spectrometer and Raman spectroscope for studying spectroscopic properties. According to UV-Vis-NIR spectra, the blue sapphires show higher Fe$^{3+}$/Ti$^{4+}$ and Fe$^{2+}$/Fe$^{3+}$ absorption peaks than those of green sapphires. Otherwise, green sapphires display higher Fe$^{3+}$/Fe$^{3+}$ absorption peaks than blue sapphires. The FTIR spectra of both blue and green sapphire samples show the absorption peaks of –OH,-CH and CO$_{2}$. The mineral inclusions including zircon, feldspar, rutile and ferrocolumbite in sapphires from this area were observed by Raman spectroscope. The spectroscopic properties of sapphire samples from Ban Bo Kaew, Phrae Province, Thailand are applied to be the specific evidence for gemstone identification.

Speaker: Jidapa Mogmued (Department of Earth Sciences, Faculty of Science, Kasetsart University)

234 Production of dried shrimp mixed with turmeric and salt by Spouted Bed technique enter the rectangular chamber.

Today, dried shrimp in the market were refused food coloring and drying until shrimp are colorful and tasty. Meanwhile, Community groups, women's health trying to produce food products come from herbs. As an alternative to consumers. The production process is also a traditional way to dry. In order to extend the shelf life longer. Sometimes, potential risks, both in quality and quantity of products. As a result, consumers are enormous. Thus, this research aims to study the possibility to produce shrimp dried mixed with turmeric and salt. Then dried shrimp mixed with turmeric and salt to keep up the quality criteria of the Food and Drug Administration-FDA It can reduce the risk of the consumer and can keep up in a kitchen Thailand. When buying shrimp from the fisherman's boat Will be made clear, clean impurities and shaking the sand to dry. Prepare a mixture of turmeric and salt. The shrimp were dipped into a beef with stirrer for 3 minutes. And scoop up shrimp salad with dried jerky. Measurement of initial moisture content averaging 83%wb. Then drying technique Spouted enter the rectangular chamber a continuous manner. Until average moisture content to 17%wb. The air temperature in the drying chamber at 180 oC and hot air speed 4.3 m/s, a state heat transfer Mass and moisture within the shrimp.In chamber when drying, the shrimp have moved freely behavior can spit water out faster does not burn.
Shaving legs of shrimp shell fragments lightweight is sorting out the top of drying chamber. Private shrimp were dried out to the front of the quad drying chamber. Power consumption 27.5 MJ / kg, divided into electrical energy 12.3 MJ / kg and thermal energy is 15.2 MJ / kg. The hot air comes from burning LPG gas burner with dual automatic. And can adjustable to room temperature drying characteristics Modulation setting.

Speaker: Mr PISUT THANTONG (KMUTNB)

235 Design and construction of portable survey meter

This work was aimed to design and construction of portable survey meter for radiation dose measuring. The designed system consists of 6 parts including GM-tube radiation detector, low voltage power supply, high voltage power supply, pulse conditioning, processing and display on android phone. The test results indicated that the ripple voltage of low and high voltage power supply were less than 1%. The maximum integral counts were found to be 3×105 cps. It was found that the developed system had small size and light weight for portable measuring system.

Speaker: Mr Warut Singseeta (Ubon Ratchathani University)

236 2D Seismic Wave Forward Modeling by Finite-Difference Method

The purpose of this work is to study and develop a forward modelling computer program of 2D seismic wave by using finite-difference method. Forward modeling is a method that shows how seismic wave propagates through particular subsurface area, and also one of the schemes in Inversion method which is used for modeling the prospect area from the acquired seismic field data. Despite the fact that this method can be done by various techniques, this work will focus on using finite-difference approximation to solve the wave equation. To clarify this, the subsurface model is built and divided into grids and nodes which represent the physical properties corresponding with seismic wave propagation. After that, the equation of motion will be solved spatially and temporally on each node by finite-difference method with the consideration of initial and boundary condition to obtain its displacement value; the displacement on the surface in a period of time can be shown as "Synthetic seismograms". In stability and accuracy test, the program will be conducted on various kinds of subsurface models, and its results will also be compared with that of the existed program. Furthermore, different value of the number of grid points per wavelength and stability constant will be tested in order to find the optimum value of each interested model.

Speaker: Mr Phudit Sombutsirinun (Chiang Mai University)

237 A Comparative Study of Gunshot Residue Obtained from M16 and AK47 Rifles for Forensic Science.

The qualitative and quantitative study of gunshot residue (GSR) obtained from M16 and AK47 rifles are reported. The GSR samples were collected from various different sources of the shooter (hand, cloth, and helmet), elapsed time, and number of shooting. The scanning electron microscope with electron dispersive X-ray spectrometry (SEM/EDS) showed that the various shapes and sizes of the GSR samples as well as unique particles were observed. The unique particles have various elemental compositions such as Pb, Ba, Sb, Ti, Zn, and Sr. According to the inductively coupled plasma-Mass spectroscopy (ICP-MS) investigation, it is found that the heavy metal concentration increases as the number of shooting. The heavy metal concentrations depend on which parts of source are studied. The results showed that the heavy metal concentration and GSR particles decrease when the elapsed time increases. In this study shows that, SEM/EDS can identify the unique particles and their elemental composition, while ICP-MS can only measure the exact concentration of heavy metals in GSR.

Speakers: Ms Plaifhon Pooyooyen, Ms Saowaluk Sodchuen

238 A Molecular Dynamics Study of the Interfacial Regions Between Polymer and Carbon-Based Nanoparticle Fillers

A novel polymer composite material with high stiffness and thermal endurance can be designed by optimizing the filler content. We investigated the microscopic properties of the interfacial regions between cis-polyisoprene (natural rubber) and carbon-based fillers, e.g. fullerenes by using classical molecular dynamics (MD) simulations. The microscopic analysis shows that increasing filler concentration results in the growing of the regions containing ordered cis-PI chain at the interfacial areas. In this work, we analysed the order parameter, e.g. local density and orientation at the interfacial and confined regions which correspond to changes in mechanical and thermal properties. These results could provide the information for the parameterisation of the coarse-grained or the continuum models.

Speaker: Dr Thana Sutthibutpong (Theoretical and Computational Science (TaCS) Center)

239 A portable flat vacuum cell and the effect of its surface adsorption

In this work, we discussed about our construction of a portable flat vacuum cell and our study of the effect of surface adsorption in the cell in which thermal atoms were trapped. The cell comprised two parallel glass plates that were separated by a narrow gap in order to accentuate the dominance of collisional frequency along the glass surface’s normal. The identification and measurement of the effect of adsorption were based on variation of a distance between the glass plates, kinetic energy of the atoms, and types of material coated on the surfaces. The result was useful in designing cold atom transport inside a cell with restricted dimension.

Speaker: Mr Nakarin Jayjong (Chiang Mai University)

240 A preliminary study on identification of Thai rice samples by INAA and statistical analysis

This study aims to investigate the elemental compositions in 50 Thai rice samples using instrumental neutron activation analysis (INAA) and to identify rice according to their types and rice cultivars using statistical analysis. As, Mg, Cl, Al, Br, Mn, K, Rb and Zn in Thai jasmine rice and Sung Yod rice samples were successfully determined by INAA. The accuracy and precision of the INAA method were verified by SRM 1568a Rice Flour. All elements were found to be in a good agreement with the certified values. The precisions in term of %RSD were lower than 7%. The LODs were obtained in range of 0.01 to 29 mg kg-1. The concentration of 9 elements distributed in Thai rice samples was evaluated and used as chemical indicator to identify the type of rice samples. The result found that Cl, Al, As, Br, K and Rb concentrations in Thai jasmine rice samples are significantly different but there was no evidence that Mg, Mn and Zn are significantly different from concentration in Sung Yod rice samples at 95% confidence interval. Our results may provide preliminary information for discrimination of rice samples and may be useful database of Thai rice.

Speaker: Dr Supalak Kongsri (Thailand Institute of Nuclear Technology)

241 A review of scalar eld cosmology: Its non-linear Schrodinger-type formulation

Standard cosmological model containing barotropic fluid in arbitrary spatial curvature and scalar field under arbitrary potential can be described in the form of non-linear Schr\"{o}dinger (NLS) formulation. The formulation leads to the simpler way in obtaining exact scalar field solutions. NLS may be useful for interpretation of wave function in quantum cosmology.

Speaker: Ms Chonticha Kritpetch (The Institute for Fundamental Study "The Tah Poe Academia Institute (TPTP)")

242 A Study of Star Formation by H$\alpha$ Emission of Galaxies in the Galaxy Group NGC 4213

This research aims to study hydrogen alpha emission, corresponding to star formation of galaxies in the NGC 4213 group that has an average recession velocity of 6,821 km/s. The imaging observations with broad-band filters (B, V and R$_\text{C}$) and narrow-band filters ([S II] and Red-continuum) were carried out from the 2.4-m reflecting telescope at Thai National Observatory (TNO). There are 11 sample galaxies in this study, consisting of 3 elliptical, 1 lenticular and 7 spiral galaxies. It was found that the late-type galaxies tend to be bluer than early-type galaxies, due to these galaxies consist of relatively high proportion of blue stars. Furthermore, the equivalent width of hydrogen alpha (EW(H$\alpha$)) tends to increase as a function of morphological type. This indicates that star formation in late-type galaxies taking place more than the early-type galaxies. Furthermore, a ratio of the star formation rate to galaxy mass also increases slightly with the galaxy type. This could be due to the interaction between galaxy-galaxy or tidal interaction occurring within the galaxy group.

Speaker: Sakdawoot Maungkorn

243 A study of two qubits system with Quantum operator formalism

A two-qubit system is studied in the quantum operator formalism to analyze the open system consisting of two atoms in a cavity. The evolution of an open system is usually described in the Kraus representation which is constructed by considering a large closed system. In this work, we consider the short time scale of the evolution of systems in terms of interaction Hamiltonian. We focus on the construction of the Kraus operators, which results in the density matrix to support the master equation. This allows analyze the stability of the entanglement of two qubits system.

Speaker: Ms Siriratchanee Thammasuwan (Authors)

244 A study the period variation rate of V1292 Taurus RR Lyrae variable star

This research was aimed to study the period variation rate of V1292 Taurus RR Lyrae variable star. The observational data was obtained on 0.5 meter Reflecting Telescope with CCD photometer camera in (Blue light, B) and (Visible light, V) bands at Regional Observatory for the Public, Nakhon Ratchasima province. The data have been analyzed to plot the light curves. From the (Observed-minus-Calculated, O-C) diagram analysis, we see that the period of this variable star is 0.5714981 days and the period variation rate is increased of 4.8669436 sec/year.

Speaker: Patsakorn Prachumlek

245 Air Pollution Estimates from Vehicular Emissions in Amphoe Muang Lampang, Thailand

In this research, engine emissions from different vehicle age, type and used fuel in Amphoe Muang Lampang in Thailand were measured and studied with a portable gas combustion analyzer. Concentrations of carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), nitrogen oxides (NOx) and sulfur dioxide (SO2), as well as exhaust gas temperature (flue temperature, FT), net calorific efficiency (Effn) and gross calorific efficiency (Effg) were measured. Together with vehicle number statistics gathered from the Lampang Land Tranport Office, results from this study will be used to estimate the amount of vehicular pollution released.

Speakers: Ms Pawika Audwing (Lampang Rajabhat University), Ms Porntiwa Poutong (Lampang Rajabhat University)

246 Analysis data of sensitive layer and charge collection electrode of monolithic pixel sensors for the ALICE ITS upgrade

In this work we will present the analysis results of the explorer-0 chips which have been irradiated by 5.9 keV X-ray from $^{55}$Fe sources. The explorer-0 chip is a prototype CMOS imaging sensor designed for new Inner Tracking System of ALICE detector. Here we focus on four important parameters, the pixel pitch, the collection electrode size, the distance between the electrode and the surrounding electronics, and the reverse bias voltage on the collection diode. The optimized values of these parameters will be used in the final design of pixel chips.

Speaker: Wanchaloem Poonsawat (Suranaree University of Technology (TH))

247 Analysis of Physical Properties and Evolution of Binary System V2790 Ori

V2790 Ori is a W Uma Eclipsing Binary with an orbital period of 0.28784200 day. From the previous investigation of its light curve, it was found that this binary system has a continuous orbital period change. A light curve of V2790 Ori was analyzed using program Maxlm DL4 and its period change was also calculated. The result revealed that the orbital period of V2790 Ori was continuously decreased at rate of 3.44623820×10$^{-3}$ seconds per year to 8.67350882×10$^{-3}$ seconds per year. From the analysis of physical parameters and model, it was found that V2790 Ori had a contact characteristic had high mass ratio. This would be the evolution of V2790 Ori would be a single star due to mass transfer of the system.

Speaker: Mr Sarawut Chulok (Department of Physics and General Science, Faculty of Science and Technology, Songkhla Rajabhat University)

248 Annealing Effects on Surface Morphology of IrMn Thin Films

IrMn alloy has been intensively studied during last few years in order to improve exchange bias strength in magnetic storage. IrMn layer is usually coupling with a ferromagnetic layer to increase sensitivity in magnetic sensor due to its critical thickness. It can maintain high exchange strength even at ultra-thin layer. In this study, thermal annealing was performed at different temperatures in Ar atmosphere and air. The surface of as-deposited samples showed smooth surface and contain small grains. After annealing, surface grains exhibited flatter and larger for Ar-annealing. However for air annealing, some very large grains were developed on IrMn thin film surface. It was identified as Mn-Oxide by using micro-Raman spectroscopy. The effects of annealing temperature and annealing time on the formation of Mn-Oxide will be discussed during the presentation.

Speaker: Ms Kanogkwan Sawaengsai

249 Application of combined gas-fired infrared and air convection drying for quality and energy consumption of instant rice

As an excellent source of nutrients, riceberry has gained more intention than white rice. However, information of instant rice obtained from riceberry is scarce. An alternative technique of instant rice preparation was therefore proposed in this work. The combined gas-fired infrared burner and air convection drying at different gas-fired infrared burner intensities was investigated. Gas -fired infrared burner intensities at 350 to 550oC were combined with a 40oC temperature and 1 m/s air velocity. The result shown that the drying rate increased with gas-fired infrared intensity, hence reducing the total drying time. The total color difference (∆E) varied from 3.5 to 4.2. Increasing gas-fired infrared intensity decreased in hardness, chewiness and gumminess, but increased the rehydration of instant riceberry. The effective moisture diffusivity increased with the gas-fired infrared intensity varying from 1.37x10-11 to 3.64×10-10 m2/s. The specific energy consumption at 550oC was 2.90 kWh/kg of water removed resulting in a 76% energy saving when compared to 350oC. This study gives a method for preparation of instant rice; it would be a good choice to instant rice in the industry.

Speaker: Dr Mali Nachaisin (sanawong_14@hotmail.com)

250 Applying Isotope Techniques for Sustainable Development of Groundwater in the Upper Chao Phraya Basin (Bang Rakam area)

The upper Chao Phaya Basin is the largest Cenozoic sedimentary basin that is located in the upper central part of Thailand. The basin is a high potential area for agricultural activities, such as growing rice, sugarcane and vegetables. In each year, the groundwater level has decreased continuously about 10-30 cm/year. Groundwater levels dropped from 5-10 m. to 10-25 m below ground surface at present. The water samples from groundwater, and surface water in Bang Rakam area were collected for analysis of stable isotopes (O-18 and H-2 in water), .tritium (H-3) and Carbon-14 (C-14) as well as chemical composition such as major cat ion and anion as well. The most of groundwater samples, they have the water as of Na$^+$- Ca$^{2+}$ - HCO$_3$$^-$ type with indicating cationic exchange between Na and calcium along the flow path. The groundwater quality in this area is good quality below the maximum allowable limit of WHO(World Health Organization) for agriculture and consumer. The $\delta$$^{18}$O and $\delta$D values of the rain water samples vary from 1.71 ‰ to -13.89 ‰ and 18.30 ‰ to – 106.59 ‰ respectively. The origin of groundwater system in this area comes from local rainfall and surface water. The groundwater samples that depth less than 30 meters below the ground surface and away two kilometres from Yom river are effective on the river. The main flow direction of the groundwater system is movement from the south western of study area by means of tritium data. The average recharge rate of groundwater system were estimated by CMB (Chloride Mass Balance) using the average of chloride content in groundwater samples, the average of chloride content in rainfall sample during 2013 to 2014 as well as the effective of rainfall amount (mm/year). It is about 220 mm/year. The Chloride mass balance method shows that 10 % of the effective annual rainfall is recharge to the aquifer. Groundwater ages using tritium content can be separated into two groups. Group 1(groundwater ages is less than 50 years ago) that groundwater samples are deep above 50 meters below the ground surface and Group 2 (groundwater age is more than 50 years ago) by the depth more than 50 meters below the ground surface.

Speaker: Mr Kiattipong Kamdee

251 Atmospheric water vapor: Distribution and Empirical estimation in the Atmosphere of Thailand

Atmospheric water vapor is a crucial component of the Earth's atmosphere, which is shown by precipitable water vapor. It is calculated from the upper air data. In Thailand, the data were collected from four measuring stations located in Chiang Mai, Ubon Ratchathani, Bangkok, and Songkhla during the years 1998-2013. The precipitable water vapor obtained from this investigation were used to define a empirical model associated with the vapor pressure, which is a surface data at the same stations. The result shows that the relationship has a relatively high level of reliability. The precipitable water vapor obtained from the upper air data is nearly equal to the value from the model. The model was used to calculate the precipitable water vapor from the surface data 85 stations across the country. The result shows that seasonal change of the precipitable water vapor was low in the dry season (November-April) and high in the rainy season (May-October). In addition, precipitable water vapor varies along the latitudes of the stations. The high value obtains for low latitudes, but it is low for high latitudes.

Speaker: Mr Sayan Phokate (Applied Physics, Faculty of Engineering, Khon Kaen Campus, Rajamangala University of Technology Isan, Khon Kaen)

252 Auroral bright spot in Jupiter's active region in corresponding to solar wind dynamic

Jupiter’s polar emission, whose brightness behavior appears to be unstable. This work focuses on the bright spot in active region which is a section of Jupiter’s polar emission. Images of the aurora were taken by Advanced Camera for Surveys (ACS) on board the Hubble Space Telescope (HST). Previously, two bright spots, which were found on May 13th 2007, were suggested to be fix on location described by system III longitude. The bright spot’s origin in equatorial plane was proposed to be at distance ~80-90 Jovian radii and probably associated with the solar wind properties. This study analyzes additional data on May 2007 to study long-term variation of brightness and location of bright spot. The newly modified magnetosphere-ionosphere mapping based on VIP4 and VIPAL model are used to locate the origin of bright spot in magnetosphere. Furthermore, the Michigan Solar Wind Model or MsWim are also used to study the variation of solar wind dynamic pressure during the time of bright spots observation. We purpose that the bright spots appear nearly the same location which corresponds to the origin in magnetosphere and the solar wind dynamic pressure should probably affect to the bright spots variation.

Speaker: Suwicha Wannawichian (Department of Physics and Materials Science, Chiang Mai University)

253 Beam Dynamic Simulation of the Thermionic RF Electron Gun with Self-generated Cathode Emission

A thermionic RF-gun is an essential component in electron injector for producing a quality electron beam for a THz radiation source at Plasma and Beam Physics Research Facility, Chiang Mai University. The RF gun consists of one and a half normal conducting resonant cavities and a side-coupling cavity which operates in pi/2-mode at frequency of 2856 MHz. In 2014, the gun design was improved by changing the position of a RF input port from horizontal coupling plane to the vertical plane in order to obtain symmetry beam at the gun exit. In this work, geometry of each main accelerating cell as well as the position of the side-coupling cavity are modified to have more symmetric electromagnetic field simulated by using the CST Microwave Studio. Beam dynamic study is performed by using PARMELA. In addition, we created the initial thermionic particle distribution obeying Maxwell-Boltzmann distribution for PARMELA simulation instead of the built-in distribution. The transverse and longitudinal profiles of the beam at cathode and gun exit are compared with the case of the built-in distribution. Furthermore, this self-generated distribution can be used as an initial thermionic emission distribution for the charged particle tracking code, ASTRA. The comparison of beam profiles at gun exit which simulated by PARMELA and ASTRA is presented and discussed in this paper.

Speaker: Chaipattana Saisa-ard (Chiang Mai University)

254 Building and testing antennas wainscot from teak and para scrap woods: Built-up Column type and Spaced Column type

In the wood production manufacturing process, there are a lot of wood scraps must be left to waste. To product a pole from the wood scrap, which help to reduce cost in the production, is to use the wood scrap more efficiently. In this work, the wood poles were be designed, constructed and tested from teak and Para wood scrap by using finger joint with Polyvinyl Acetate. To constitute of these poles with being 4 inches thickness, 4 inches wide and 1 meter length were be tested in two types; built-up column and spaced column. To determination the ability of forced endurable was be acted on the vertical wainscot or compression test of wood parallel to grain by following the standard. The stipulation of the provisions of the Engineering Institute of Thailand announced that ability of forced endurable or compression test of wood parallel to grain must not less than 91 kN or 90 kg/cm2; respectively. In the results were found that ability of forced endurable of wainscots form teak and Para wood scrap has more standard value, and the maximum value of ability of forced endurable was 204 kN. The wainscot in spaced column type used less wood scraps and glue volume than the wainscot in built-up column type.

Speaker: Mr Jamon Wasuratmanee (KMUTNB)

255 Calcium oxide synthesis from cockle shells. The catalyst For the production of biodiesel from palm oil.

This research study Calcium oxide synthesis from cockle shells for catalyst in biodiesel production from palm oil. The shells are calcium is transformed into calcium oxide. This is a powerful catalyst for the transesterrifcation reaction. The research was burned cockle shells at 900 °C for 5 hours. The ratio of methanol : oil is 9 : 1 molar. The temperature reaction at 80 °C for 30 minutes. The amount of calcium oxide powder 1-5% mass of oil. Found that calcium powder 3% shown the best quality biodiesel in highest standards level and % productivity. Due to the density in the standard criteria ASTM D 1298, 860 kg/m$^3$ – 900 kg/m$^3$, the viscosity is criterion standard ASTM D 445, 3.5 cSt - 5 cSt,. The color is compliant biodiesel is transparent. and pH is be neutral.

Keywords: Biodiesel Transesterification Cockle shell calcium oxide

Speaker: Ms Subaidah A wae (Authors)

256 Characterization of Structural and Optical Properties of CsI:Tl Crystals With Different Precursor Purity

Cesium iodide doped with Thallium (CsI:Tl) is one of the most materials used for radiation detector applications. In this work, the CsI:Tl crystals that made from the material sources with different precursor purity were investigated by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), Raman scattering, UV-Vis spectroscopy and photoluminescence (PL). The purpose is to verify effects of precursor purity on structural and optical properties of CsI:Tl crystals. It is expected that type and level of impurities in the precursor is directly related the structural and optical properties. With a modified homemade Bridgman–Stockbarger technique, CsI:Tl samples were grown in two levels of CsI and TlI reactant materials, i.e., having as a very high purity of 99.999 % and a high purity of 99.9 %. XRD showed a good quality of CsI:Tl crystals. It exhibited a cubic structure with a lattice constant of 0.457 nm. From the lower-purity raw materials, the crystal was found in an orange color with a lattice constant of 0.456 nm. CsI:Tl surface morphology by SEM exhibited a smooth surface with some parallel crystal facets. By EDX measurement, elements of C, O, Al and Br were observed for both samples. The total amount of impurity in the sample with a 99.99% purity seems to higher that in the sample with a 99.999% purity. The brighter PL emission was obtained from the orange crystals suggesting impurities. Other details of investigation will be discussed during the presentation.

Speaker: Mr Poramin Sintham (Department of Physics, Faculty of Science, Chulalongkorn University)

257 Classification of Glutinous rice RD6 Grain Using Machine Vision and Support Vector Machine

We report here the use of machine vision and support vector machine for automatic identification of Glutinous rice RD6. This project is motivated from the problem of maintaining purity of RD6 seed stock, since they can mutate back to its parent KDML105. Seed stock is needed to be checked to ensure that contamination percentage does not exceed the excepted value. We use flat bed scanner to capture the image of rice seeds. The grain features, i.e. grain length and width, seed area, perimeter length, circularity, centroid position relative to the interception of length and width, are extracted. Support vector machine is used to find the hyperplane to separate the features of RD6 and its parent. Our experiments of 500 seeds of RD6 shows that the accuracy of our classification system can reach 0.5%, which satisfy the requirement of pure seed stock.

Speaker: Ms Pananya Somwong

258 Comparison of Characteristics of Hydroxyapatite Powders Synthesized from Cuttlefish Bone via Precipitation and Ball Milling Techniques

The aim of this work was to compare characteristics of hydroxyapatite synthesized by precipitation and ball milling techniques. The cuttlefish bone powder was a precursor in calcium source and the di ammonium hydrogen orthophosphate powders was a precursor in phosphate source. The hydroxyapatite was synthesized by the both techniques such as precipitation and ball milling techniques. The phase formation, chemical structure and morphology of the both hydroxyapatite powders have been examined by X-ray diffractometer (XRD), Fourier transform infrared spectroscope (FTIR) and field emission scanning electron microscope (FESEM), respectively. The results show that the hydroxyapatite synthesized by precipitation technique formed hydroxyapatite phase slower than the hydroxyapatite synthesized by ball milling technique. The CO$_3$$^-$ group appeared in the hydroxyapatite synthesized by ball milling technique, but not appeared in another. The morphology of the hydroxyapatite from the both techniques were sphere like shapes and particle size was about in nano scale. The average particle size of the hydroxyapatite by ball milling technique was less than those synthesized by precipitation technique. This experiment indicated that the ball milling technique take time less than the precipitation technique in hydroxyapatite synthesis.

Speaker: Kridsada Faksawat

259 Construction of Earth's field NMR signal transmission system

The NMR signal transmission system at earth magnetic field was constructed. The system consists of 5 important components: Arduino Mega 2560 microcontroller, frequency generator module (DDS synthesizerAD9850), switching integrated circuit (DG419), operational amplifier (THS3001) and audio-power amplifier. The microcontroller was programmed to receive the pulsed width values from computer and control the frequency generator connected to the microcontroller. The two signals from the digital pin of Arduino (square waves) and the AD9850 synthesizer (sine waves) were then mixed together using DG419 to give pulsed-audio frequencies. Afterwards the signal was sent to the op-amp circuit and continually transmitted to the audio-power amplifier to achieve 40 Watts power. It was found that, the constructed system can be performed the radio pulses in the range of audio frequencies which corresponds to the Larmor frequency for earth’ field NMR.

Speaker: Mr Klitsadee Yubonmhat

260 Correlation between Electrical Resistivity and pH of Lateritic Soil

Soil is heterogeneous medium which consist of liquid, solid and gaseous phases. Natural soils of various types have different electrical properties due to the composition, structure, water content, pH and temperature. This research aims to study the correlation of electrical resistivity for predicting pH of lateritic soil. The samples of soil were collected from farm of Kasetsart University Chalermphrakiat Sakonnakhon Province Campus in Thailand. The electrical conductivity was investigates by EC meter and converse to electrical resistivity and the pH was investigate by pH meter. Then analyzed the relationship between variables using statistical methods were the correlation coefficient Spearman Rank and simple regression found that the electrical resistivity was associated with the pH of lateritic soil.

Speaker: Mr Somkuan Photharin (Faculty of Science and Engineering)

261 Correlation between Io's lead angle and the satellite's magnetic footprint

This research studies on the nature of aurora feature on Jupiter, especially the aurora that connects to its satellite, Io. Jupiter has a large magnetosphere, as a result of strong magnetic field strength. This magnetosphere corotates with Jupiter and extends over all of Galilean satellites. The interaction between Jupiter’s rotating magnetic field and Io cause plasma particles to flow along the magnetic field line in directions toward both north and south hemispheres. Some particles will penetrate into Jupiter’s ionosphere and collide with atmosphere particles, leading to aurora emission, at the position of Io’s footprint. Io is surrounded along its path, by a cloud of plasma particles with high density, which is called Io torus. This torus enhances the effect of bending magnetic field lines when they pass Io and result in inaccuracy of the prediction of longitudinal position of Io footprint. This shift of longitudinal prediction can be mapped to the shifted position of Io, which is called lead angle. Our objective is finding the relation between all three parameters, which are magnetic field strength, Io footprint brightness and lead angle at the same Io footprint position or the same Io longitude. We use VIPAL magnetic field model, develop by Hess et al. (2011) to trace along the magnetic field line and finding magnetic field strength at any given position. This tool is vital for determination of the relation between magnetic field strength, Io footprint brightness and lead angle.

Speaker: Dr Suwicha Wannawichian (Department of Physics and Materials Science, Chiang Mai University, Chiang Mai, Thailand)

262 CuFeO$_2$ formation using fused deposition modeling 3D printing and sintering technique

CuFeO$_2$ is a metal oxide mineral material which is called delafossite. It can potentially be used as a chemical catalyst, and gas sensing material. There are methods to fabricate CuFeO$_2$ such as chemical synthesis, sintering, sputtering, and chemical vapor deposition. In our work, CuFeO$_2$ is prepared by Fused Deposition Modeling (FDM) 3D printer. The composite filament which composed of Cu and Fe elements is printed in 3 dimensions, and then sintered and annealed at high temperature to obtain CuFeO$_2$. Suitable polymer blend and maximum percent volume of metal powder are studied. When percent volume of metal powder is increased, melt flow rate of polymer blend is also increased. The most suitable printing condition is reported and the properties of CuFeO$_2$ are observed by scanning electron microscopy, and dynamic scanning calorimeter, X-ray diffraction. As a new method to produce semiconductor, this technique has a potential to allow any scientist or students to design and print a catalyst or sensing material by the most conventional 3D printing machine which is commonly used around the world.

Speaker: Mr Ahamad Salea (Advanced Material Processing Laboratory,Material science and engineering program, Faculty of science, Mahidol university, Bangkok, 10400, Thailand)

263 Deep Shear Wave Velocity of Southern Bangkok and Vicinity

Bangkok is located on the soft marine clay of the Lower Chaopraya Basin which can amplify seismic wave and affect to building shaking. Shallow shear wave velocity to depth 30 m. (V$_s$30) is widely studied recently but data of deeper layer to bedrock still absent. The missing data are useful for earthquake engineering design and ground shaking estimation.

This study aims to measure deep shear wave velocity profile down to bedrock of southern Bangkok region. Microtremor measurements with 2 seismographs using Spatial Autocorrelation (SPAC) technique were done at 8 sites. The data was collected in day time on linear array geometry varied between 5-2,000 m. Long natural wavelength at the frequency 0.2-0.6 Hz. was detected at many sites. The results show that shear wave velocity function of Southern Bangkok is between 100-2,000 ms$^{-1}$ and indicate that the bedrock depth is about 600-800 m, except at Bang Krachao. Very deep shear wave data of many sites are ambiguous due to noise and survey limitation.

Speaker: Mr Thanagrit Wongpanit (Department of Earth Sciences, Faculty of Science, Kasetsart University )

SPC 2017 Poster.pdf

264 Design and Construction of a Small Vacuum Furnace

The general high temperature furnaces are usually used in the atmosphere, a sample it consequently contacts the air that has pollutants, there makes the sample impure by exposure in a particular way to be not required and difficult to control gas that requires to an interaction within a sample. A heating technique in a vacuum environment is required to fix the referred problems. The purpose of this research is designing and construction of a small vacuum furnace. A cylindrical graphite was chosen as the material of the furnace and the cylinder aluminum sheets employed to prevent the heat radiation that transfers from the furnace to the chamber wall. Using a rotary pump, the system can be pumped down to 30 mTorr, the heating wire drives the graphite furnace to 700 °C while the temperature of the chamber enclosure remains relatively low. Heat losses from the graphite furnace by conduction, convection, and radiation were analyzed. The dominating heat loss was found to be caused by the blackbody radiation, which can thus be used to estimate the relationship between graphite furnace temperature and the drive power needed. The cylindrical graphite furnace has an inner diameter of 44 mm, the outer diameter of 60 mm and 45 mm in height, only 355.5 W of power is needed to drive the furnace to 700 °C.

Keyword: vacuum furnace, thermal analysis, graphite radiation, radiation shielding.

Speaker: Ms piroonrat peawbang (Ubon Ratchathani University)

265 Design and Development of Emittance Measurement Device by Using the Pepper-pot Technique

Transverse emittance of a charged particle beam is one of the most important properties that reveals the quality of the beam. It is related to intensity, size and angular displacement of charged particles in transverse phase space. There are several techniques to measure the transverse emittance value. One of a practical method is the pepper-pot technique. This research concentrates on development of a pepper-pot device to measure the transverse emittance of electron beam produced from a thermionic cathode RF electron gun at the Plasma and Beam Physics Research Facility, Chiang Mai University. Simulation of beam dynamics is conducted by using programs PARMELA, ELEGANT and self-developed C code. The geometry and location of the pepper-pot and its corresponding screen station are included in the simulation. The result from the study is used to design and develop the pepper-pot experimental station. Results from the measurements and the simulation prediction will be presented and discussed in this contribution.

Speaker: Ms Siriwan Pakluea (Chiang Mai university)

266 Determination of $\omega-\phi$ mixing at leading order

The $\omega-\phi$ mixing plays an important role in particle interactions involving vector mesons. The SU(3) flavor symmetry predicts the flavor mixing in vector meson nonet. The $\omega-\phi$ mixing angle was predicted by several physical processes, such as decay rate, radiative decay of $\omega$ and $\phi$. In this work, we calculated vector meson masses by using chiral Lagrangian at leading order (LO) and fitted them to the physical vector meson masses. We adjusted two low energy parameters, $m_V$ and $b_D$, at the ideal mixing angle. We found that the value of the low energy parameters can recover the $\rho-\omega$ mixing, which is the well-known property of vector meson at LO. Furthermore, when we treated the mixing angle as a free parameter, together with the $m_V$ and $b_D$, and refitted to the physical masses, we obtained the mixing angle differ from the ideal mixing angle by 2 degrees, and the vector meson masses slightly differ from their physical values.

Speaker: Mr Ruchipas Bavontaweepanya (Mahidol University)

267 Determining the appropriate altitude to improve accuracy in rainfall estimation from radar reflectivity data.

In present day, rainfall estimation by weather radar is widely used. Meteorologists use various z-r relationships to appropriate rainfall estimation for different study areas which have different factors such as topography, climate, rain pattern, types of clouds, etc. This research aims to determine the appropriate altitude of radar reflectivity (Z-Level) to provide accurate rainfall estimation. This research will use radar reflectivity data (Z) from Omkoi radar station, which is owned by the Department of Royal Rainmaking and Agricultural Aviation (DRRAA). It uses radar reflectivity data from 1.5 to 13.5 kilometers above mean sea level. We convert it to daily rainfall from radar (R) using Omkoi Z-R relationship (Z=92.4R^1.5) and compare the result to daily rainfall measured by rain gauge stations (G) from 42 rain gauge stations of Thai Meteorological Department (TMD), covering areas within radius of Omkoi radar station (240 km) in the northern of Thailand. The study will consider comparing various statistics of rainfall from radar (R) and rainfall from rain gauges (G), such as correlation coefficients, root mean square error (RMSE) and the characteristic distribution of graphs (Scatter Plot). The results show that the radar reflectivity data in altitude 3.5 km above mean sea level are the most suitable to be used to determine the Z-R Relationship. Therefore, determination of Z-R relationship of Omkoi radar station should be based on the radar reflectivity data at altitude 3.5 km above mean sea level.

Keywords : Z-R Relationship, Rainfall Estimation, Weather Radar, Radar Reflectivity, Rain gauge, Altitude, Correlation Coefficient, Root Mean Square Error, RMSE, Scatter Plot

Speaker: Mr Manot Lakkham (Kasetsart University)

268 Development of electropinning system have a hemispherical collector

This research project has developed electrospinning system for performance increasing of the system. Operating system was changed from the computer controlled to command on the machine and status of system show on display on LCD screen. Moreover, this research has developed working control programs with Arduino board. Component of electrospinning system are source of voltage, flow rate control system and metal collector which can be synthesis fiber in nano scale. Then, calibration of flow rate can be adjusted by delay value and solution injection time of 10 ml leads to relation between flow rates with delay. The system can adjust flow rate that requirements. The performance test use polyvinylpyrolidone solution for spinning fiber and analysis characteristic by using scanning electron microscope techniques (SEM).
The improvement of the flow rate has resolution at 0.1 mm/hr. Hence, the electrospinning system can be processed fiber in order nano scale. the relation between flow rate with delay was delay equal 1,255 of divided by the flow rate. The resolutions of flow rate are adjusted at 0.1 ml/hr. The fiber was fabricated from the conditions of 10 kv at distant between the tip of needle and ground collector at 15 cm. Morphology of fibers are smoothness. And, size of fibers are uniformly

Speaker: Mr piriya praneekit

269 Development of Beam Diagnostic System for Natural Rubber Vulcanization Linac

This research focuses on design and development of beam diagnostic system of an electron linear accelerator (linac) for natural rubber vulcanization at the Plasma and Beam Physics Research Facility, Chiang Mai University. The main components of the accelerator include a DC thermionic electron gun and an S-band standing-wave linac. The system will be used to produce electron beams with adjustable energy in the range of 0.5 to 4 MeV and a pulse repetition rate of 20 to 400 Hz with the maximum pulse duration of 4 μs. The maximum electron pulse current is expected to be 100 mA. Design and development of beam diagnostic instruments to measure electron beam energy, pulse current and electron dose are underway. The beam energy will be measured in ambient air after the beam exiting the linac by using a dipole magnet, a phosphor screen and a CCD camera. Measurements of current and charge of electron beam are performed by using a current transformer and a Faraday cup, respectively. This contribution will describe and discuss on the results of the design and construction of the beam diagnostic system as well as the results of the beam measurement.

Speaker: Mr Ekkachai Kongmon (Chiang Mai University)

270 Development of measurement system for gauge block interferometer

We developed a measurement system for collecting and analyzing the fringe pattern images from a gauge block interferometer. The system was based on raspberry pi which is an open source system with python programming and opencv image manipulate library. The images were recorded by the raspberry pi camera with 8 mega pixel capacity. The noise of images was suppressed for the best result in analyses. The low noise images were processed to find the edge of fringe patterns using the contour technique for the phase shift analyses. We tested our system with the phase shift pattern between a gauge block and a reference plate. The phase shift patterns were measured by a Michelson type of interferometer using the He-Ne laser with the temperature controlled at about 20 $^0$C. The results of the measurement will be presented and discussed.

Speaker: Sakchai Chomkokard

271 Development Thermoelectric Properties of Al-doped ZnO Materials for Thermoelectric Module and Power Generator

The main objective of this work is to synthesized Zn0.96Al0.04O thermoelectric materials for fabrication thermoelectric modules and invention thermoelectric generator. The Zn0.96Al0.04O sample was prepared by a conventional solid state reaction method. The formation of structure was proved by X-ray diffraction and the thermoelectric properties were measured. The results showed that the Zn0.96Al0.04O displayed thermoelectric materials and showed thermoelectric properties as higher than that of ZnO based. The Zn0.96Al0.04O thermoelectric modules displayed the power output was increase with number of module, increase difference temperature and operating at high temperature. The Zn0.96Al0.04O thermoelectric generator showed high performance for electric generator at high temperature. The sixteen Zn0.96Al0.04O legs thermoelectric generator of this work produced electric power at1.4 mW at 800 (when T = 600 ◦C). The Zn0.96Al0.04O materials can be applied for application of thermoelectric generator at high temperature.

Speaker: Mr Singkarn Chanprateep

272 Digital Lock-in Amplifier based on Soundcard Interface for Physics Laboratory

Jinda Sinlapanuntakul, Puchong Kijamnartsuk, Chanthawut Jetjamnong, S. Chotikaprakhan
Department of Physics, Faculty of Science, Kasetsart University, Bangkok, 10900 Thailand.

Keywords: Digital lock-in amplifier, RLC circuit, Physics laboratory.

The purpose of this paper is to develop a digital lock-in amplifier based on soundcard interface for undergraduate physics laboratory. Both series and parallel RLC circuit laboratory are tested because of its well-known, easy to understand and simple confirm. The sinusoidal signal at the frequency of 10 Hz – 15 kHz is generated to the circuits. The amplitude and phase of the voltage drop across the resistor, R are measured in 10 step decade. The signals from soundcard interface and lock-in amplifier are compared. The results give a good correlation. It indicates that the design digital lock-in amplifier is promising for undergraduate physic laboratory.

[1] Tepelea L, Gavrilut I, Neamtu O, Gergely E, Gacsadi A, 17th “Building Services, Machanical and Building Industry Days” International Conference, 13-14 Oct. 2011, Debrecen Hungry.
[2] Ye B, Chen F, Li M, Int. J. of Signal Processing, Image Processing and Pattern Recognition 8(4), 361 (2015).

Speaker: Jinda Sinlapanuntakul

273 Eclipsing Binary in the Field of Open Cluster NGC 2126

Eclipsing binaries with pulsating components are very crucial objects for asteroseismology. We present the results of an analysis of photometric time series observations for the intermediate-age open cluster NGC 2126 acquired during the years 2004, 2013 and 2015 with the aim to detect new variable stars and to study binary systems. The CCD photometric light curves in V band of the eclipsing binary with pulsating component named V551 Aur are presented. Our four epochs of light minimum along with others compiled from the literature were used to revise the orbital period which is 1.173 days. The Wilson-Devinney technique was used to analyze the light curves for determining a new set of the system’s parameters. According to the analysis, the solution shows that V551 Aur is a detached eclipsing binary system with a mass ratio of about 0.77 and inclination of about 73 degree. A frequency analysis of the eclipse-subtracted light curve gives a main frequency of f$_1$ = 7.713 c/d. The ratio between the orbital and pulsation periods with the value of 9.05 may indicate the existence of resonance or a possible causal relation to tidal effects suggesting that the 9th harmonic of the orbital period is excited by the tidal forces.

Speaker: Ms Nareemas Chehlaeh (Chiang Mai University)

274 Effect of Bacterial Cellulose and its Carbon Nanofiber Derivatives Addition on the Compressive Strength of Cement Paste Composite.

The mechanical properties of cementitious materials, widely applied in construction, could be improvedby reinforcement with cellulosic natural fibres. In this study, another type of natural fibers, i.e. the bacterial cellulose (BC) obtained from coconut jelly (nata de coco) was added to cement paste to form the reinforced composites. The coconut jelly was thoroughly washed and blended prior to mixing with cement pastes. Up to 15 wt% of BC was added to the cement paste. The workability of the cement composites was controlled to be the same for every mix. The samples were then tested for compressive strength at the age of 7 and 28 days. The improving trend of the properties for BC-cement composites was not clearly seen. However, when the BC was pyrolyzed, carbon nanofibers (CNF) were obtained. The cement pastes with CNF addition showed an improvement for their compressive strength. The strength increased with CNF amount and aging time. The morphology of both BC-cement and CNF-cement composites at their fracture surfaces was observed under scanning electron microscopy (SEM). The correlation between the mechanical property and microstructure was discussed.

Keywords: Bacterial Cellulose; Carbon Nanofiber; Cement; Compressive Strength

Speaker: Mr Nuttawat Parse (Khon Kaen University)

275 Effect of Carbon Fiber and Nano-Silica Addition on the Microstructure, Electrical and Mechanical Properties of Fly Ash Geopolymer

Geopolymer is an environmental friendly construction material which has a potential for replacing cement. In the present study, the addition of carbon fiber and nano-silica in geopolymer paste was studied in terms of the electrical and mechanical properties, and the microstructure. The geopolymer paste was made from fly ash by blending it in Na$_2$SiO$_2$/NaOH solution using the liquid/ash ratio of 0.4. Up to 2 wt% of nano-silica and 5 wt% of carbon fiber were added in geopolymer paste. In each mix, the workability of the paste was tested and controlled using a mini-slump test. After casting, the composite pastes were cured at 25C or 60C for 24 hr. The property and microstructure measurements were performed at 7, 14 and 28 days. For the electrical property, the I-V curve of each sample was measured using a 4-point probe method. The electrical resistivity generally increased with nano-silica addition but decreased with carbon fiber content. On the other hand, mechanical test showed that the compressive strength did not have a clear trend when any additive was mixed. The phase formation and functional groups were analysed using X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) while the fractured surface morphology after compression was investigated under a scanning electron microscope (SEM).

Keywords: geopolymer; carbon fiber; nano-silica; electrical property; compressive strength

Speaker: Mr Pichainarong Boomprasert (Khon Kaen university )

276 Effect of Cationic ions in mud and Laterite to indigo blue interactions using molecular dynamics simulation

Molecular dynamics simulations of Cationic ions in mud and Laterite, indigo blue molecules and cotton molecules have been carried out to investigate effect of Cationic ions to indigo blue interactions. The results show that appearances of cations improve both indigo blue - indigo blue interaction and indigo blue - cotton interaction. This result obey the experimental results.

Speaker: Mr Keerati Maneesai

277 Effect of doping by different transition metal oxides on the elastic and structural properties of recycled borosilicate glasses

Recycled borosilicate glass (RBSG) was used a composition in 80RBSG–20Na2O glass systems doped with different transition metal oxides (TMOs) (where TMOs = V2O5, Cr2O3, CuO, ZnO, ZrO2, Ag2O and CdO). The ultrasonic velocities (both longitudinal and shear) of glass systems were measured by using pulse echo technique. Measurements were carried out at 4 MHz frequency at room temperature. The densities of the glasses were performed by Archimedes’ principle and used n-hexane as the immersion liquid. The elastic moduli, Poisson’s ratio and micro-harness are found to be rather sensitive to the glass composition. The obtained results were showed that the properties of glasses were decreased when doped the amount of TMOs. The amount of TMOs have the effect on rigidity of the glass network structure. These results related to the number of non-bridging oxygens (NBOs) and supported by FTIR spectroscopy.

Keyword: Recycle borosilicate glasses; Elastic moduli; Pulse-echo technique

Speaker: Poonnaphob Sopapan (Department of Physics, Faculty of Science, Ubon Ratchathani University)

278 Effect of External Economic Field and Market Temperature on Stock-Price Hysteresis and Price-Return Distribution: Monte Carlo simulation on the Ising Agent-Based Model.

In this work, the stock price variation in a form of dynamic hysteresis was investigated via Monte Carlo simulation. The Ising spin Hamiltonian was considered as the level of ‘disagreement’ (in the social economic) which has to be minimized for the market sustainability. The Ising spin directions (either +1 and -1) were considered to refer to an agent’s intention to perform his action on trading (either to buy or to sell) in the stock market. The effect of economic variation in a form of periodic cycle was also considered via the external field term in the Ising Hamiltonian. The stochastic Monte Carlo simulation was performed on this Ising system to elucidate the market trends on the overall. The single spin flip Metropolis algorithm was used to update the spin directions. Waiting until the system was in steady state, the excess demand and supply were then extracted via the Ising magnetization. After that, the stock price were calculated from this magnetization to observe its variation with a function of time and external economic field. From the results, it was found that the external field parameters (the economic influence strength and period) and market temperature have significant effect on the stock price changes, resulting in different characteristic of price-return distribution. Specifically, the return distribution becomes broader in shape with increasing the external influence strength, which is due to that the higher encouragement in price changing causes larger gaps among stock-price intervals. On the contrary, the distribution becomes less broad with increasing the market temperature, which is caused by a higher level of ‘monetary’ fluctuation which inspires more frequent trading. Consequently, the price gap becomes less in size and hence the distribution broadness. This reason can also be applied to describe how the distribution evolves with changing the economic period. After that, the non-linear empirical fit was performed on judging applicability of the considered Ising model on describing real markets. However, due to available states in the Ising model are only +1 and -1 whereas there could be many more in real system, this could be the reason why the distribution was too narrow to extract diversity of time-lag in the return-distribution for drawing constructive fits (i.e. too few data points to achieve fine R-squares). However, the exponent values obtained from the fits still give suggestive results how the market reacts when changing the external influence parameter and temperature for the specified system, i.e. the system where each agent has only intention to buy or to sell with the same magnitude. For instance, these results can be used as a basis for further analysis of how external economic parameters and market temperature affect the price-distribution and its time-lag availability.

Speaker: Dr Yongyut Laosiritaworn (Chiang Mai University)

279 Effect of Lightweight aggregates prepared from fly ash on lightweight concrete performances

Lightweight aggregates were prepared from fly ash of by-products from the paper industry. The influence of the ratio of clay to fly ash and processing conditions on lightweight aggregates properties were investigated. It was found that the amount of fly ash directly affected to porosity of lightweight aggregates. Lightweight aggregates with the ratio of clay to fly ash at 80:20 wt% using the sintering temperature at 1210$^{o}$C exhibits the bulk density of 1.66 g cm$^{-3}$ and the compressive strength of 25 MPa. The replacement of coarse aggregates with lightweight aggregates at 100 wt% for concrete production showed the ultimate properties of concrete with density of 1780 g cm$^{-3}$, water absorption of 3.55%, compressive strength of 40.94 MPa and thermal conductivity of 0.77 W m$^{-1}$ K$^{-1}$. The concrete had more than 25% weight reduction while keeping a similar compressive strength to an ordinary concrete. This is revealed that lightweight aggregates could be applied into structural concrete because it was able to reduce work load and increase safety factor of construction.

Speaker: Dr Rudeerat Suntako (Department of Physics, Faculty of Liberal Arts and Science, Kasetsart University Kamphang Saen Campus, Nakhon Pathom 73140, Thailand)

280 Effect of Mg on Mechanical Properties of Mg$_x$Fe$_{(3-x)}$O$_4$ Prepared by Solid State Reaction

The synthesis of Mg$_x$Fe$_{(3-x)}$O$_4$, X = 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 and 0.9 was performed by solid state reaction with various rotating speed of ball milling (160, 240 and 320 rpm). Samples were characterized by X-Ray diffraction (XRD), scanning electron microscopy (SEM). Shrinkage and Vickers were used to determine the phase structure, physical properties and mechanical properties of magnesium ferrite. The result of XRD pattern shows that the single phase could be obtained with a rotating speed of 160, 240 and 320 rpm. Also, by using JCPDS200-002-013 showed ferrites phase and crystallize size with a range of 1.54-2.57 $\mu$m. Moreover, the maximum percentage of shrinkage, 16.641 was obtained with X=0.8 and a rotating speed of 240 rpm. The highest density of ceramic of 3.834 g/cm$^3$ was obtained with X=0.1 and a rotating speed of 320 rpm. The Vickers hardness of 7.442 x 10$^3$ kg/m$^2$ was obtained with X=0.8 and a rotating speed of 160 rpm.

Speaker: Aekasit Sutthapintu

281 Effect of Shelf Life to Void Under Die for Die Attach Process in Integrated Packaging

This research studied about reduction of void under die in die attach process. Die attach process is one that is very importance process in the integrated circuit(IC) packaging. A popular adhesive material used for attaching between die and leadframe or substrate of a package which is an epoxy. Snap cure process is also important to make a completed epoxy due to cross linking to enhance microstructure of epoxy stiffness. The shelf life before snap cure process effect to void under die of multichip package because of a long time of attaching cause risk to happen void under die.In experiment, the wait time before snap cure were varied from 0 until 8 hours with a step of 1 hour and analyzed the void under die of epoxy by die shear test, x-ray and reliability test after take the test samples out from the snap cure. The results confirmed that the wait time effect to void under die of die attach process in IC packaging.

Speaker: varunee paktramook

282 Effect of thick barrier in a gapped graphene Josephson junction

We study the Josephson effect in a gapped graphene-based superconductor/barrier/superconductor junction as using the Dirac-Bogoliubov de Gennes (DBdG) equation for theoretical prediction. A massive gap of this regime is induced by fabricating a monolayer graphene on substrate-induced bandgap and superconductivity is acquired by the proximity effect of conventional superconductor (s-wave superconductor) through top gate electrodes. This Josephson junction is investigated in case of thick barrier limit that is pointed out the effect of applying a gate voltage V$_\text{G}$ in the barrier. We find that the switching supercurrent can be controlled by the gate voltage V$_\text{G}$ and the effect of thick barrier can influence the switching linear curve. When the barrier is adjusted to manner of a potential well which is inside the range of -mv$_\text{F}$$^\text{2}$$\leq$V$_\text{G}$$\leq$0, the supercurrent in thick barrier case is examined to the same behavior as the thin barrier case. The controlling supercurrent through the electrostatic gate is suitable for alternative mechanism into experimental test.

Speaker: Tatnatchai Suwannasit (King Mongkut’s University of Technology North Bangkok)

283 Effecting aging time of epoxy molding compound to molding process for integrated circuit packaging

This research studied about effecting aging time of epoxy molding compound (EMC) that effect to reliability performance of integrated circuit (IC) package in molding process. Molding process is so important of IC packaging process for protecting IC chip (or die) from temperature and humidity environment using encapsulated EMC. For general molding process, EMC are stored in the frozen at 5 degree celsius and left at room temperature at 25 degree celsius for aging time on self before molding of die onto leadframe is 24 hours. The aging time effect to reliability performance of IC package due to different temperature and humidity inside the package. In experiment, aging time of EMC were varied from 0 to 24 hours for molding process of SOIC-8L packages. For analysis, these packages were tested by x-ray and scanning acoustic microscope to analyze properties of EMC with an aging time and also analyzed delamination, internal void, and wire sweep inside the packages with different aging time. The results revealed that different aging time of EMC effect to properties and reliability performance of molding process.

Speaker: Jirayu Tachapitunsuk

284 Effective capacitance of metallic single electron transistor

We proposed a method to calculate the effective capacitance of a metallic single-electron transistor using the quantum Monte Carlo method to describe the Coulomb blockade effect. The effective capacitance depended on the induced gate charge, temperature, and conductance of the system. Furthermore, the results can be used to calculate the effective charging energy, which can characterize the strength of the Coulomb blockade effect. In the Coulomb blockade regime, the effective charging energy was approximately equal to charging energy. In particularly, the effective charging energy decreased with an increase in the conductance and temperature.

Speakers: Dr prathan srivilai, Mr pipat harata

285 Effects of an intermediate c-GaN buffer layer on structural and optical properties of AlN films on MgO (001) substrates

Effects of an intermediate cubic GaN (c-GaN) buffer layer on structural and optical properties of AlN films on MgO (001) substrates via radio frequency plasma assisted molecular beam epitaxy (RF-MBE) were investigated with Raman scattering, X-ray diffraction, and UV spectroscopy. The samples studied in this work are AlN films grown under Al-rich condition with and without intermediate c-GaN buffer layer. There are 2 types of c-GaN intermediated layers, which are a one-step grown buffer layer with a 7-nm-thick c-GaN layer and a two-step grown buffer layer with a sequence of a 7 nm- and a 200 nm-thick c-GaN layers. Raman spectra recorded using an excitation wavelength of 473 nm of AlN films with a two-step grown c-GaN buffer layers showed the cubic phase related phonon modes at 662 cm$^{-1}$ and 902 cm$^{-1}$, which are corresponded to TO and LO, respectively. On the other hand, the AlN film directly grown on MgO (001) substrate showed only the hexagonal AlN (h-AlN) related phonon modes at 610 cm$^{-1}$, 653 cm$^{-1}$ and 884 cm$^{-1}$, which are corresponded to A$_1$ (TO) and E$_2$ (high), and A$_1$ (LO), respectively. While, the AlN film with a 7 nm-thick intermediate c-GaN layer showed a mixed vibrational modes between c-AlN and h-AlN. As a result, we found out that the structural phases of AlN can be modified from hexagonal to cubic phases with an insertion of a two-step grown c-GaN buffer layer as intermediate layer between the AlN film and the MgO substrate. This result was confirmed by X-ray diffraction measurements, both in 2$\theta$/$\omega$ scan and reciprocal lattice mapping modes. Therefore, a use of an intermediate c-GaN buffer is the key for the growth of highly pure c-AlN film. Besides, results of UV spectroscopy measurements established the Cauchy dispersion relation for reflective index, n (λ), in a range of 200 to 400 nm. For long wavelength limit, reflective index of the c-AlN and h-GaN was examined to be 2.00 and 2.15, respectively.

Speaker: Mr Nutthapong Discharoen

286 Electrical properties of two-dimensional zinc oxide in hexagonal, (4,4)-tetragonal, and (4,8)-tetragonal structures by using Hybrid Functional calculation

Two-dimensional (2D) material is a specific type of materials with its thickness being thinned down to single atomic layer. In many materials, their 2D sheets have been reported to yield very different physical properties from those of their ordinary bulk and other forms of nanostructures. For instance, the band gap of 2D semiconductor sheets can vary from zero band gap (semi-metals, e.g., graphene) to wide band gap insulator (e.g., BN sheet). Among many available metal oxide semiconductor, the monolayer zinc oxide possesses many intriguing properties, such as wide band gap, high charge carrier mobility, being flexible and inherited optical transparency, so it has become a new generation semiconductor of flexible and transparent optoelectronics. However, the growth of the 2D structure in typical semiconductors is very difficult to control as appropriate synthesized technique for such the structure is not well established yet. Specifically, the synthesis route to form the ultrathin 2D material requires breaking of crystal symmetry and fostering of anisotropies in crystal growth. However, successful epitaxial growth of ZnO monolayer in hexagonal structure on graphene substrate was recently achieved and reported to have band gap up to 4 eV. In addition, sub 100-nm-sized ZnO nanosheet in hexagonal wurtzite and tetragonal structures were also found to successfully grow in the solution synthesis using surfactant molecules as a facet at the water-air interface. These then illuminate some possibilities in nano-engineering the structure to achieve ultrathin semiconductor with desired properties. However, the guidelines to comprehend this structure-property relationship should be firstly established. Therefore, in this work, the two-dimensional zinc oxides were studied in tetragonal and hexagonal structures. The electronic calculation was performed using Heyd-Scuseria-Ernzerhof (HSE) hybrid density functional, which mixes the exact non-local exchange of Hartree-Fork (HF) theory with the local exchange and correlation potential of Perdrew-Burke-Ernzerhof (PBE) functional from generalized gradient approximation (GGA). The calculation results showed that the band gaps of 2D ZnO structures are 4.20 eV in hexagonal, 3.06 eV in (4,4)-tetragonal, and 4.59 eV in (4,8)-tetragonal structure, respectively. In term of structure stability, the hexagonal ZnO has more energetic favorable than both of (4,4)- and (4,8)-tetragonal ZnO for about 5.10 eV and 3.15 eV. The small energy differences between these 2D ZnO phases suggest that the phase transformation between these structures is reversible, suggesting band gap values appearing in range (instead of discrete). Consequently, to synthesis 2D ZnO with a single pure phase require great attention during the growth. However, the underlying band gap differences between these 2D ZnO structures open the band gap tunable opportunity (when mixing) to be implemented in optoelectronics via nano-engineering.

Speaker: Mr Chumpol Supatutkul

287 Electricity Cogenerator from Hydrogen and Biogas

This research studied about electricity cogenerator from Hydrogen and Biogas and the factors that cause that effecting Hydrogen from Aluminum which was a cylindrical features. By using a catalyst was NaOH and CaO, it was reacted in distilled water with percentage of Aluminum : the catalyst ( NaOH and CaO ) : the distilled water, which were 2 : 8 : 1, respectivety. And the percentage of Hydrogen was highest 64.73 % by flowing of constant gas at 0.56 liter/minute and brought to mix with Biogas afterwards, that have been led to electricity from generator 1 kilowatt and studied the voltage and electricity as well.
The result of study the factors that cause to the effecting Hydrogen. The research outcomes were concentration of solutions that caused amount and percent of maximum Hydrogen was to at 10 %wt and 64.73 % which rate of flowing of constant gas 0.56 liter/minute as temperature 97 degree Celsius. After that led Hydrogen was mixed by Biogas next, conducted to electricity from generator and leveled the voltage of generator at 220 Volt in the order to the voltage as the voltage an electric with in house. There after the measure of electricity current and found electricity charge would be constant at 3.1 Ampere. And rate of Biogas flowing and Hydrogen, the result were the generator used Biogas rate of flowing was highest 9 liter/minute and the lowest 7.5 liter/minute, which had rate of flowing around 8.2 liter/minute. Total Biogas was used around 493.2 liter or about 0.493 m3 and Hydrogen had rate of flowing was highest 2.5 liter/minute, the lowest 1 liter/minute.

Speaker: Wasan Pinate (Program of Physics, Faculty of Science,Rajabhat MahaSarakham University)

288 Elemental composition analysis of stony meteorites discovered at Phitsanulok, Thailand

Teerayut loylip1,2*, Suwicha Wannawichian2,3
1Graduate School, Chiang Mai University, Chiang Mai, Thailand
2National Astronomical Research Institute of Thailand (NARIT), Chiang Mai, Thailand
3Department of physics and Materials Science, Chiang Mai University, Chiang Mai, Thailand

E-mail: teerayut@Narit.or.th

Abstract

 A meteorite is a fragment of iron, stone or stony–iron rock. The falling of meteorites to Earth's surface is part of Earth’s accretion process from dust and rocks in our solar system.  When these fragments come close enough to the Earth to be attracted by its gravity, they may fall into the Earth. Following the detection of objects that fall from the sky onto a home in Phitsanulok on June 27, the meteorites were analyzed by Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD) instruments. XRD analysis shows presence of three main elements in the meteorites, which are Forsterite, Enstatite and Anorthite. The data from SEM analysis shows that the meteorites are mainly composed of Fe-Ni and Fe-s. The meteorite is Achondrite, a class of meteorite which does not contain Chondrule. The meteorites in this work are thought to be part of a large asteroid.

Keyword : Meteorite, SEM, XRD, Achondrites, Chondrule, Forsterite, Enstatite, Anorthite

Speaker: Mr Teerayut Loylip

289 F and D Supersymmetry Breaking in AdS Space

The Nelson-Seiberg arguments of the connection between supersymmetry breaking and R-symmetry breaking is determined for gauged and localized supersymmetry theories with generic superpotential. This is a study of symmetry breaking in supergravity theory. The metastable vacua of supergravity from the contribution of F and D auxiliary fields in superpotential are determined, and also anti-de Sitter vacua. One find that the cosmological constant and vacuum energy could also be lifted to a small positive value.

Speaker: Mr Sirapat Lookrak (Mahidol university)

290 Fabrication and preparation of Mg-reducing 12CaO•7Al$_2$O$_3$ cement for enhancing of electrical and optical properties

Polycrystalline Ca$_{12}$Al$_{14}$O$_{33}$ (C12A7) were synthesized by conventional solid state reaction method and were calcined/sintered at 1300˚C. The Mg powder was used to reduce oxygen inside of nano-cage to form free electron in the cage for enhancing the electrical and optical properties of C12A7 cement compound. The crystal structure of the C12A7 and Mg-reducing C12A7 were characterized by X-ray diffraction, morphology and element composition were investigated with scanning electron microscope. In addition, Optical properties were measured by UV-VIS-NIR spectrophotometer that shown transition of absorption because the samples change from white to green powder. Finally, the sample was measured electrical conductivity and carrier concentration by the Hall Effect which can be confirmed existence of electron in the structure and the enhancing properties will be reported.
Keywords: Ca$_{12}$Al$_{14}$O$_{33}$, Mg reducing agents.

Speaker: Chalermpol Rudradawong

291 First Principles Study of Structural Stability and Electronic Band Structure of Al2C Monolayer and Nanotube

Excitonic solar cells (XSC) based on heterojunction nanostructure composed of low-dimensional materials have gained a great deal of interest due to its large interface area and hence the high possibility in generating excitons. In general, the power conversion efficiency (PCE) of this XSC depends strongly on the interface band alignment between donor and acceptor materials. Therefore, low-dimensional materials with adjustable band alignment are highly desirable for achieving high PCE applications. Among many candidates, Al$_2$C monolayer(s) with band gap of 1.05 eV has been proposed as a suitable material for photovoltaic applications. The similar expectation is also paid for Al$_2$C nanotube as it possesses even higher surface area ratio. However, structural stability and band gap of the nanotube have not been reported yet, even though there has been assumption that it may be possible to tune the band gap by varying nanotube radius. Therefore, in this work, we use density functional theory based on generalized gradient approximation (GGA) and hybrid functional (HSE06) to investigate structural stability and band gap of both Al$_2$C monolayer and nanotube. From the results, both GGA and HSE06 band gaps of Al$_2$C monolayer agree well with previously reported data, which confirms the validity of our calculations. Then, for the Al$_2$C nanotube, we found that its band gap is somewhat sensitive to the size and the helicity of nanotube. Specifically, the band gap for zigzag (n,0) nanotube vanishes (i.e. the metallic state) when nanotube diameter (d) is reduced to about 8.0 Å. On the other hand, the band gap for zigzag (0,n) nanotube increased to about 1.2 eV under the decrease of nanotube diameter to 7.5 Å. Furthermore, at small diameter limit (d < 20 Å), the strain energy as a function of nanotube radius indicates that Al$_2$C nanotube is even more stable than the widely studied SiC$_2$ nanotubes. With radius dependence, the wide range and adjustable band gap of Al$_2$C nanotube provide its capability to be tuned in obtaining suitable/desired band alignment for enhancing PCE of XSC.

Speaker: Mr Sittichain Pramchu (Department of Physics and Materials Science, Faculty of Science, Chiang Mai University)

292 First-principles study of native defects in ZnRh$_2$O$_4$ spinel

Transparent conducting oxides (TCOs) are widely used for many applications. Typically, most of TCOs are intrinsically n-type semiconductors and are difficult to be doped for p-type conductivity. The spinel ZnRh$_2$O$_4$ has been recognized as a potential p-type TCO. In this work, we present energetics and electronic properties of native defects including vacancy, interstitial and antisite defects in ZnRh$_2$O$_4$ by mean of first-principles calculations. Computed pinned Fermi levels are closed to the valence band edge in any possible growth conditions. It is thus difficult to grow an n-type ZnRh$_2$O$_4$, which is consistent with experimental facts. Based on our calculated formation energies, we observe that the Zn vacancy (V$_{Zn}$) acts as a deep acceptor and has relatively high formation energy, and thus V$_{Zn}$ is unlikely to be responsible for the p-type conductivity. By contrast, we find that Zn substituting for Rh (Zn$_{Rh}$) acts as an acceptor forming a shallower transition level than that of V$_{Zn}$. Under O-rich/Rh-poor and Zn-rich/O-poor conditions, Zn$_{Rh}$ is found to be the major source of unintentional p-type conductivity in ZnRh$_2$O$_4$. To enhance hole concentration, we suggest experimentalists to grow ZnRh$_2$O$_4$ under high oxygen partial pressure with low Rh concentration.

Speaker: Ms Kodchakorn Simalaotao (Kasetsart University)

293 Forbush decreases detected at the Princess Sirindhorn Neutron monitor in the 24$^{th}$ Solar Cycle

Neutron monitors (NMs) are ground-based detector designed to measure the cosmic ray (CR) intensity, sometimes observe a sudden reduction in galactic CR intensity, the so-called Forbush decreases (FDs) event. The Princess Sirindhorn NM (PSNM) was established in 2007, an NM64-type and 3 bare tubes located at the world's highes geomagnetic vertical cutoff rigidity 16.8 GV was installed at Doi Inthanon in Thailand, 2565 m above sea level. In this work we study the FDs in CR intensity detected at PSNM that occurred during the 5 years of 2010-2015 in the 24$^{th}$ solar cycle. We analyze the FDs at the Oulu NM in Finland in order to identify and compare them. We identify 46 FDs at both PSNM and Oulu NMs then we used the student's t-test to assess difference in the mean between simultaneous or non-simultaneous of FDs event. We found that the 46 FDs, 22 are simultaneous and 24 non-simultaneous. Furthermore, we also found that student's t-test analysis reveals that FDs at PSNM have smaller intensity variation of main phase duration of main phase than at Oulu NM. The results of the present statistical analysis that support the PSNM can provide CR data of reliability comparable to that of the Oulu NM. This work also provides unique data of FDs and solar modution.

Speaker: MALIWAN DEEPROM (UBON RATCHATHANI UNVERSITY)

294 Full Characterization of Two-beam Magneto-optical Trap

In standard magneto-optical trap (MOT), three pairs of cooling beams orthogonally intersect at the magnetic field minimum produced by anti-Helmholtz coils. The degree of off-centering seriously determines the trapping velocity, lowest temperature reached, decoherence time, and the shape and density of the cold atomic cloud. Our alternative two-beam trap was designed for efficiently cooling and capturing rubidium-85 atoms while maximizing the optical accessibility to the cold gas. In contrast to the MOT, only two focused counter propagating laser beams were employed. The confocal configuration provides additional trapping force due to spatial light shift in the transverse direction with respect to the beam axis while the trap potential is still predominated by the interplay between the Doppler shift and Zeeman shift. Here, we have performed the first full characterization of the two-beam trap and discussed parameters that influence the trap efficiency. The trap number, temperature, density and geometry of the atomic cloud are compared with the standard MOT.

Speaker: Mr Nuttanan Tanasanchai

295 Gamma-ray shielding and structural properties of strontium–lead–silicate glasses

The gamma-ray attenuation coefficients of strontium–lead–silicate glasses have been measured by using a narrow beam transmission technique for gamma ray photon energies at 122, 662, 1173 keV and X-ray attenuation technique for gamma ray photon energies at 74.228 keV. These coefficients were then used to obtain the values of mass attenuation coefficients and half value layer. In order to evaluate gamma-ray shielding properties for glass samples, mass attenuation coefficients have been calculated with the WinXcom computer software. The results have been used to calculate half value layer parameters. The molar volume, FTIR, longitudinal velocity and longitudinal modulus have been used to study the structural properties of the prepared glass system.

Keywords: Glasses, Radiation shielding, Gamma-ray attenuation coefficients

Speaker: Pattaranipa Gunhakoon (Department of Physics, Faculty of Science, Ubon Ratchatani University, Warinchamrab, Ubon Ratchatani, 34190,Thailand.)

296 Geometry-Dependent Faraday Rotation in Strained Graphene

We investigate coherent single photon in the infrared regime traveling in the positive z direction passing through a single layer of strained graphene. The angle of rotation relates to space deformation by the terms of directional dependent fermi velocity. Analytical expressions of full quantum mechanics, by second-quantization approach, are obtained for components of the magneto-optical tensor.
The transmission, reflection and faraday angle can be calculated.

Speaker: Mr Phusit Nualpijit (Kasetsart University)

297 Giant Dielectric in Sb-Single Doped Rutile-TiO2 Ceramics

Sb-single doped rutile-TiO$_2$ (STO) ceramics were prepared by a conventional mixed oxide method. The high-dielectric performance with giant dielectric constant value ($\epsilon$'$\approx$10$^4$) with low dielectric loss (tan$\delta$<0.05) of STO ceramics over a wide temperature range were obtained. Scanning electron microscope coupled with energy-dispersive X-ray analysis (EDX) and X-ray diffraction technique were used to characterize the microstructure and crystal structure, respectively. The existence of Ti$^{3+}$ was confirmed using X-ray photoelectron (XPS) technique. X-ray absorption near edge structure (XANES) technique were also carried out. The origin of the observed high-dielectric performance in STO ceramics was investigated.

Speaker: Mr Apiwat Boonkhuang (Khon Kaen University)

298 Gibbs Energy Additivity Approaches in Estimation of Kinematic Viscosities of n-Alkane-1-ol

Alcohols are solvents for organic and inorganic substances. Kinematic viscosity of liquid is important transport properties. In this study model for estimating n-alkane-1-ol kinematic viscosity are correlated to the Martin’s rule of free energy additivity. Data available in literatures are used to validate and support the proposed equations. The kinematic viscosity of n-alkane-1-ol can be easily estimated from its carbon number (z) and temperatures (T). The Bias, average absolute deviation and coefficient of determination (R$^2$) in estimating of n-alkane-1-ol are -0.17%, 1.73% and 0.999, respectively. The kinematic viscosity outside temperature between 288.15 and 363.15 K may be possibly estimated by this model but accuracy may be lower.

Speaker: Suriya Phankosol

299 Identification of charm quark jets at the CMS experiment

The hadronic products that result from proton-proton collisions at the Large Hadron Collider (LHC) can give rise to jet formation that can be detected be the Compact Muon Solenoid (CMS) detector. Several interesting physics, both Standard Model (SM) and Beyond Standard Model (BSM), processes can result the final states with charm quark jets. Analyzes rely on the algorithms that try to identify the flavour of these jets, called heavy-flavour taggers. In addition to the widely used b-tagger to identify the bottom quark jets, the new algorithm is developed to identify charm quark jets while rejecting bottom and light flavour jets. Such the algorithm is consequently called c-tagger. C-tagger relies on the characterestic of charm quarks hadronizing to long lifetime D mesons. Consequently, they travel a significative distance before decaying into showers of detectable particles, called jets. These new tracks arised from this decay do not point back to the primary interaction vertex. Thus, charm jets can be distinguished by particular properties such as secondary vertices from displaced tracks with respect to the primary interaction. The algorithm to identify charm jets, c-tagging algorithm, is invented based on Combined Secondary Vertex algorithm for b-tagger. C-tagger uses a Boosted Decision Tree (BDT) as multivariate analysis (MVA) technique to study a set of jet properties in order to identify jets originated from charm quarks. It is the first of its kind at the CMS collaboration. The c-tagger is integrated into the CMS software (CMSSW). It can be used in supersymmetry (SUSY) searches for new particles such as stop, the SUSY partner of standard model (SM) top, that may subsequently decay to a charm quark and the lightest supersymmetric particle (LSP), and for SM precision measurements in the data taking at the Large Hadron Collider (LHC) in 2016 and 2017.

Speaker: Kittikul Kovitanggoon (Chulalongkorn University (TH))

300 Implementation of a Parallel Simplex Algorithm

The Nelder-Mead method or Simplex algorithm was proposed in 1965 by John Nelder and Roger Mead. It is widely used to fi?nd minimum values of speci?c functions in Mathematics and Physics. We implemented a framework for minimization algorithm
in C++ based on the non-parallel Simplex scheme and a parallel adaptation. For the
parallel simplex algorithm, we used the Message Passing Interface (MPI) which is a C language library for parallel programming. We show that this parallel Simplex method yields a higher computational efficiency than the non-parallel Simplex algorithm.

Speaker: Thanachot Nasawad

301 Instability analysis of dust acoustic solitons in dusty plasma with both trapped electrons and ions

The reductive perturbation technique is applied to obtain the dust acoustic wave equation from the governing equations for dust grains in plasma. Some electrons and ions can be trapped in the charged dust potential and the populations of these two particles will be described by the Maxewellian distribution. The growth rate can be determined by applying a long-wavelength perturbation to the perpendicular direction of the dust acoustic soliton.

Speaker: Sarun Phibanchon (Burapha University)

302 Investigating differences in light stable isotopes between Thai jasmine rice and Sung Yod rice

We report the differences in light stable isotopes between two kinds of Thai rice (Thai jasmine and Sung Yod rice). Thai jasmine rice and Sung Yod rice cultivated in the northeast and the south of Thailand. Light isotopes including 13C, 15N and 18O of Thai jasmine rice and Sung Yod rice samples were carried out using isotope ratio mass spectrometry (IRMS). Thai jasmine rice (Khao Dawk Mali 105) was cultivated from Thung Kula Rong Hai area, whereas Sung Yod rice was cultivated from Phathalung province. Hypothesis testing of difference of each isotope between Thai jasmine rice and Sung Yod rice was also studied. The study was the feasibility test whether the light stable isotopes can be the variables to identify Thai jasmine rice and Sung Yod rice. The result shows that there was difference in the isotope patterns of Thai jasmine rice and Sung Yod rice. Our results may provide the useful information in term of stable isotope profiles of Thai rice.

Speaker: Dr Chunyapuk Kukusamude (Thailand Institute of Nuclear Technology)

303 Investigation of using wavelet analysis for classifying pattern of cyclic voltammetry signals

Wavelet analysis is an excellent technique for data processing analysis based on linear vector algebra since it has an ability to perform local analysis and is able to analyze an unspecific localized area of a large signal. In this work, the wavelet analysis of cyclic waveform was investigated in order to find the distingue feature from the cyclic data. The analyzed wavelet coefficients were proposed to be used as selected cyclic feature parameters. The cyclic voltammogram (CV) of different electrodes consisting of carbon nanotube (CNT) and several types of metal phthalocyanine (MPc) including CoPc, FePc, ZnPc and MnPc powders was used as several sets of cyclic data for various types of coffee. The mixture powder was embedded in a hollow Teflon rod and used as working electrodes. Electrochemical response of the fabricated electrodes in Robusta, Arabica, blend coffee and cocoa at varied concentrations was measured with scanning rate of 0.05V/s from -1.5 to 1.5V respectively to Ag/AgCl electrode for five scanning loops. The CV of blended CNT electrode with some MPc indicated the ionic interaction which can be the effect of catalytic oxidation of saccharides and/or polyphenol on the sensor surface. The major information of CV response can be extracted by using wavelet analysis with Harr mother wavelet and then the discrimination of these wavelet coefficients of each data group can be separated by principal component analysis (PCA). The PCA results indicated the clearly separate groups with total contribution more than 90% representing from PC1 and PC2.

Speaker: Arthit Jityen

304 Low-cost standalone multi-sensor thermometer for long time measurements

We present a portable device for long-time recording of the temperature at multiple measuring points. Thermocouple wires are utilized as the sensors attached to the objects. To minimize the production cost, the measured voltage signals are amplified and sequentially relayed via a multiplexer to a single microcontroller. The observed temperature and the corresponding date and time, obtained from a real-time clock circuit, are recorded to a memory card for further analysis. The device is powered by a rechargeable battery and placed in a rainproof container, thus it can operate under outdoor conditions. A demonstration of the device usage in a mandarin orange cultivation field of the Royal project, located in the northern Thailand, is illustrated.

Speaker: Mr Nakorn Kumchaiseemak (department of physics, Kasetsart university)

305 Magnetic Force Microscopy Observation of Perpendicular Recording Head Remanence

In this work, magnetic force microscopy (MFM) was utilized to observe the magnetic write head remanence, which is the remaining out-of-plane magnetic field on magnetic write heads after a write current is turned off. This remnant field can write unwanted tracks or erase written tracks on a magnetic media. The write head remanence can also occur from device and slider fabrication, either by applying current to the write coil during the inspection or biasing the external magnetic field to magnetic recording heads. This remanence can attract magnetic nanoparticles, which is suspended in cleaning water or surrounding air, and cause device contamination. Samples used in this study were magnetic write heads that were etched with two different gas etching recipes. MFM images were used to examine locations of the remnant field on the surface of magnetic recording heads. Experimental results revealed that the remanence occurred mostly on the shield and the initial direction of magnetic dipoles has the influence on the location of the write head remanence. In addition, it was found that different etching gases have the effect on the pole tip remanence.

keywords: remnant field, pole tip remanence, perpendicular magnetic write heads, MFM

Speaker: Mr Poumin Dilekrojanavuti (Silpakorn University)

306 Magnetic Force Microscopy Study on Wide Adjacent Track Erasure in Perpendicular Magnetic Write Heads

One of significant problems limiting the performance of perpendicular magnetic write heads is wide adjacent track erasure (WATEr), causing stored data near and also far from a written track being erased. Understanding WATEr mechanisms and its locations is crucial both for design and process engineers. Typically, the presence of WATEr in magnetic write heads is monitored using a spin-stand technique; however, it cannot accurately identify sources and locations where WATEr is presented on magnetic write heads. In this paper, a phase-contrast magnetic force microscopy (MFM) was used to observe and analysis the failure of magnetic write heads due to the WATEr problem. During MFM imaging, the magnetic write head was energized by a DC current. The induced out-of-plane magnetic field was then detected by scanning a MFM probe across the surface of the magnetic write head. MFM images were then mapped with experimental results from WATEr measurement by the spin-stand. Results revealed that WATEr can be created by several factors, i.e. the structure of magnetic domains and walls from material discontinuities and the magnetic field leakage at different locations on magnetic write heads.

Keywords: far track interference, adjacent track interference, magnetic recording heads, WATEr, MFM

Speaker: Ms Poramaporn Ruksasakchai (Silpakorn University)

307 Materials selection for Repairing Case Study: Marine propeller shafts

This research studies the material’s properties which aim to analyze and evaluate the appropriateness of selection the material for repairing propeller shafts of fishing boats. The materials’ preferential ranking is used as the method of study, which uses the criterion of materials’ properties, including mechanical properties and chemical properties, as an assessment tool. The result of research specifies the most suitable material for repairing propeller shafts of fishing boats. The economic value of materials is another topic that has been implemented as another assessment tool. Consequently, this research finding will be beneficial to fishermen in choosing the right propeller shafts for their work.

Speaker: Mr Siva Sitthipong (Marine and Coastal Resources Institute)

308 Measurement of Electron Beam Energy by Using Dipole Magnet and Alpha Magnet

One of critical beam parameters for a linear accelerator is a beam energy. This research studies on measurements of energy and energy spread of electron beams produced from a thermionic cathode RF electron gun at the Plasma and Beam Physics Research Facility, Chiang Mai University. An alpha magnet is used for energy filtering by using energy slits located inside the alpha magnet vacuum chamber. These energy slits equipped with stepping motor and programmable encoder are used together with a current transformer downstream the alpha magnet to measure the electron beam energy and energy spectrum. Moreover, the electron beam energy can also be measured by using a dipole magnet for bending electrons to the screen and a CCD camera is used to capture a transverse image of electron beam. An image capture program is installed in a PC computer for recording and analyzing the transverse distribution of electron beam. Finally, beam dynamic simulation using programs PARMELA and ELEGANT are performed to compare the result with the measurement data.

Speaker: กิตติพงษ์ เตชะแก้ว

309 Measurement of Plasma Parameters of Argon DC Discharge Plasma by Mean of Double Electric Probe

Electrical double probe measurement is one of the techniques used to find plasma parameters. Plasma parameters which electrical double probe can determine are electron temperature and electron density. Plasma parameters can be extracted from I-V characteristic graph of double probe which is inserted inside plasma. A program which is responsible for all calculations and control are written in Labview 2013 environment. The program will collect current and voltage data from HP4140B and automatically analyze for plasma parameters. The experiments was held in pure argon plasma in 0.20 torr of pressure and 25.5, 27.5 and 30.0 mA of discharge current while the distance between generating plasma electrode is 7 cm. The double probe results show that electron temperature remains constant at 1 eV while electron density directly varies to discharge current in the range of 4$\times$10$^9$ – 6$\times$10$^9$ cm$^{-3}$. The comparison between double probe and single probe results shows that relative discrepancy of electron temperature and electron density are 16.55% and 26.42% respectively

Speaker: Chatchai Sirithipvanich (Chulalongkorn)

310 Measurement of Side Wall Angles of Magnetic Recording Heads with a Nano-scale Pole Tip using Magnetic Force Microscopy

Fabrication of perpendicular magnetic recording heads in hard disk drives involves many processing steps and control parameters. One of the control monitors is side wall angles of the write pole tip which is typically measured by a scanning electron microscope (SEM). SEM observation is, however, a destructive testing as magnetic recording heads were damaged by electron bombarding. This paper presents an alternative indirect method to inspect side wall angles of write head pole tips by using a magnetic force microscope (MFM). The benefit of this method is that test samples have not been damaged after inspection. During MFM imaging, magnetic recording heads under test were biased with a DC current. A high coercivity MFM probe coated with FePt was employed to ensure that a magnetic dipole moment of a MFM probe was not reversed when scanning pass through areas having strong magnetic field intensity. A MFM image was then post processed in order to calculate side wall angles of magnetic pole tips. Results obtained from MFM measurement revealed the effect of the direction of probe scanning; however, those show a good agreement with results taken by a standard SEM method.

Keywords: magnetic write heads, perpendicular magnetic recording heads, side wall angle, MFM

Speakers: Ms Achara Phuagprapun (Silpakorn University), Mr Chatchai Kerbut (Silpakorn University)

311 Mechanical and Physical Properties of Banana Fiber (Three Species) Reinforced Epoxy Resin Composite

The aim of this research was to study mechanical and physical properties of epoxy composites reinforced by the fibers of banana were analyzed. Three different specimens were made by varying the species of Musa ABB CV. Kluai “Namwa”, Musa balbisiana Colla.at and Musa (AAA group) "Kluai Hom thong" at 12% by weight. Specimens were formed by hand-layup process. The tensile strength, tensile modulus, flexural strength, flexural modulus, impact strength, density and water absorption of the composite were investigated and microstructure of the composite material with Scanning Electron Microscopy (SEM). The experimental design was 3X7 factorial in completely randomized design (CRD) with 3 replications.
Experimental results show that the tensile strength, tensile modulus, impact strength, density, water absorption and the analysis of the microstructure found that mechanical properties of the composites increased because internal bond adhesion between fiber and matrix is well formed and tensile strain associated with the ability to absorb and distribute the force evenly across the surface of the composites. Moreover, the void between the fiber and matrix, resulting in the mechanical properties of the composite, is decreased.

Speaker: CHamp Pongsathorn

312 Mechanical Properties of Cement/Bacterial Nano-Cellulose Composite

Cement is a very important material for building and construction but the main drawback is its brittleness due to high porosity. The brittleness of cement was found to be improved by reinforcing the cement matrix with celluloses extracted from plants. In present work, we studied another type of natural cellulose produced by bacteria, i.e. bacterial nano-cellulose (BNC). The BNC was obtained from the coconut jelly (nata de coco) by cleaning, blending, freeze-drying, and blending again to produce finely dispersed BNC ready to be mixed into cement paste. The liquid to cement ratio was set to 0.45 and the BNC of 0.1, 0.3, 0.5 and 0.7 wt% was added to the mixture. The workability of each mix was tested and controlled. After casting, the samples were demolded after 1 day and soaked in Ca(OH)2 solution. At 7 and 28 days age, the samples were tested for mechanical properties: compressive and flexural strengths. It was found that with the appropriate amount of BNC reinforcement, the brittleness of the cement paste composites could be improved. However, excessive amount of BNC degraded both compressive and flexural strengths. The scanning electron microscope (SEM) was used to observed the fracture surfaces of the samples after mechanical tests. The change in mechanical properties could be explained from the distribution of BNC in the cement matrix.

Speaker: Mr Dulayawit Palaporn (Khon Kaen University)

313 Micro-Raman Investigation of Selective-area Growth of Cubic GaN on [110]-Stripe Patterned GaAs (001) Substrate by MOVPE

In this work, the cubic GaN with AlGaN interlayers was selectively grown on the [110]-stripe patterned GaAs (001) substrate by metal organic vapor phase epitaxy (MOVPE). Since the cubic phase of GaN is meta-stable and hexagonal phase always exist, the structural phase and features of the film were investigated by micro-Raman spectroscopy and scanning electron microscopy (SEM), respectively. From the cross-sectional SEM images, the morphology of the film was nearly-trapezoidal shape with the flat surfaces. The (118) facet of top surface and (111)B facet of side surface were responsible for the vertical growth and lateral overgrowth, respectively. As for the results from Raman spectra observed by various excitation wavelengths: 633nm, 532nm, and 473nm, the longitudinal-optical frequency (LO) of cubic GaN, as well as the E$_2$(high) of hexagonal GaN were detected in both vertical growth and lateral overgrowth. The integrated Raman intensities of LO including E$_2$(high) were considered and then the LO/E$_2$(high) ratio were calculated in order to qualitatively compare the amount of cubic to hexagonal phase of GaN. With the same tendency in vertical growth and lateral overgrowth, the ratio of LO/E$_2$(high) presented the progressively decrease with the laser wavelength decrease. This may be indicated that, as far from the substrate, the cubic phase tended to have less quality or be transformed to hexagonal phase. Besides, at lateral overgrowth, the phonon frequencies of LO peaks shifted to the lower wavenumber which may be due to the tensile stress occurred during the growth.

Speaker: Nattamon Suwannaharn

314 Microstructural Improvement of Hydroxyapatite-ZrO2 Composite Ceramics via Thermal Precipitation Techniques.

Hydroxyapatite-ZrO$_2$ composite ceramic were synthesized using a thermal precipitation techniques. The chemical precursors were prepared from di-ammonium hydrogen orthophosphate, calcium oxide (CaO) derived from chicken eggshell, zirconium dioxide (ZrO$_2$) and distilled water. The mixture were heated at the various temperatures from 100 to 700$^o$C in the furnace with an incremental temperature of 100$^o$C. The ZrO$_2$ contents in the composite ceramic were varied from 0 to 15 percent weight of CaO. The prepared composites were then annealed at 300, 600 and 700$^o$C for 4 h in air. The crystal structure, function group and morphology of all samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) and universal testing machine (UTM), respectively. The results indicated that the undoped-ZrO$_2$ samples hydroxyapatite phase with a hexagonal structure. However, the hydroxyapatite was transformed to the tri-calcium phosphate after thermal treatment at 700$^o$C. For the doped-ZrO$_2$ samples, the hydroxyapatite and ZrO$_2$ phases were found. Moreover, the result showed that the compressive strength of hydroxyapatite-ZrO$_2$ composite ceramic increased with increasing the ZrO$_2$ content.

Speaker: Mr Aekgaran Sangmala

315 Modeling Disease Spreading Dynamic via Magnetic Ising Spins Distribution: The Stochastic Monte Carlo and Neural Network Analysis

In this work, the disease spreading under the framework of SIS (susceptible-infected-susceptible) compartment model was investigated using the magnetic Ising model, the stochastic Monte Carlo simulation, and the knowledge based Neural Network analysis. The defined systems were lattice-like and varied in sizes to observe the finite size effect, where the agents (either susceptible or infected) were represented by the directions of the Ising spins (either +1 or -1). During the Monte Carlo simulation, each agent was randomly allocated on the discrete lattice cell and interacts with its neighboring agents for disease transmission. The +1 and -1 'magnetization' profiles were recorded as well as the basic reproduction number. From the simulation results, the characteristic number of susceptible and infected agents as a function of time were found to prominently depend on the system sizes, the agent concentrations (i.e. number of agents per available cells), and the infectious period. Specifically, the basic reproduction number was found to rise more sharply with increasing population density up to some points and become saturated afterwards. Similarly, the enhancement in infectious period shifts the balance between S-I curve to the infected agent side as expected. These results imply the key factors in this disease spreading dynamic as the infectious period and the ‘incubation period’. Note that the ‘incubation’ in this sense is rather different from the traditional incubation that is defined as the time required to change from being susceptible to infected (infectious), the so called being exposed. Nevertheless, in this work, this exposed state was not directly considered but the ‘incubation’ was arisen from the population density (which reflects on the time/probability for changing from susceptible to infected agent), and the transmission probability. As is seen, quite a number of degree of freedom is associated to this study framework, the knowledge based Neural Network was then used to establish this complex relationship among parameters. The multi-layer perceptron in the form of input-hidden-output layers was used to formulate the parameter dependencies. The population density, the transmission probability, and the infectious period were used as input parameter, whereas the basic reproduction number was used as the output parameter. Up to 2 hidden layers with up to 40 nodes in each layers were used to extract the optimized network architecture, which is still in ongoing process. The preliminary results on this part show the good agreement between the predicted outputs (from Neural Network prediction) and the targeted outputs (from actual data) was found. The scattering plot between these outputs suggest a linear trend line with satisfied R-square. This therefore confirms the validity of using Neural Network for modeling the dynamic of the SIS disease spreading scope and giving profound database on the topic for future deployment.

Speaker: Dr Wimalin Laosiritaworn (Chiang Mai University)

316 Moisture Measurement in Paddy Rice

The study on measurement of moisture content in paddy rice by capacitance method, using the principle of physics is capacitance that relate with dielectric of water. The study use IC555 frequency circuit for measure moisture content. We put the paddy rice in parallel plates that replace a capacitance in circuit. The frequency will change follow by capacitance of paddy rice, by the way if the frequency is high the capacitance will low. In this paper the moisture content that measure by IC555 frequency circuit have a different from ISO method around ±1% in the range of moisture content 14% to 20%.

Speaker: Ms Panadda Klomklao (Department of Physics, Faculty of Science, Kasetsart University)

317 Monte Carlo Production Management in CMS Experiment

Monte Carlo (MC) samples are the essential components for almost all particle physics related experimental analyses. These samples are widely used for the preparations of physics analyses and for predictions regarding future experiments. The MC production for a large-scale experiment like CMS is a huge effort in which billions of simulated events for thousands of individual physics processes are produced, with different conditions (e.g. detector alignment), different inputs (e.g. parton shower v/s ME generators) and many workflows (e.g. parametrised simulation vs detailed GEANT-based simulation). In 2012, the web-based service Monte Carlo Management (McM) was developed and put in the production in order to aggregate the information needed for the configuration and prioritization of the events production, to ensure the book-keeping and all the processing requests placed by the physics analysis groups as well as to interface with the CMS production infrastructure. This talk describes the strategy followed by the CMS experiment to collect, manage, process and track MC requests, as well as the tools written and deployed to satisfy the MC needs of each physics group with automated computing operations tools.

Speaker: Gurpreet Singh Chahal (Chulalongkorn University (TH))

318 Monte Carlo simulation of cosmic radiation dosimetry to aircrews at the world highest rigidity cutoff

Galactic cosmic radiation emanates from outside the solar system, while occasionally a disturbance in the sun’s atmosphere leads to a surge in radiation particles.
Protection is provided by the sun’s magnetic field, the earth’s magnetic field, and the earth’s atmosphere. Dose rates are dependent on the altitude, the geomagnetic latitude and the solar cycle. For occupational exposure to ionizing radiation, which includes aircrew, the International
Commission on Radiological Protection recommends maximum mean body effective dose limits of 20 mSv per year (averaged over 5 years, with a maximum in any one year of 50 mSv). Radiation doses can be calculated by using a computer modeling program, FLUKA. At an altitude of commercial aircraft (about 10 kilometers above sea level), the polar regions have a radiation dose greater than the equatorial regions about three times.

Speaker: Mr dumrongsak rodphothong

319 Nature of Seismicity of the Northern Thailand

This research studies the characteristics of local earthquakes occurring in the northern Thailand during the year 2006 to 2015. 780 seismic events (ML ≥ 0.1) are recorded and analyzed from densed seismic networks in Thailand. Seisan earthquake analysis software was used to calculate the magnitudes and to relocate the earthquake locations with the seismic velocity model of Thailand (TRF, 2014).
The result of this study indicates that the earthquakes in the study area consist of small to moderate earthquake and occurred at shallow depth (range from 0-33.8 kilometer). Most earthquakes have magnitudes of 0.1-3. Relocations of these earthquakes suggest that the distribution of the earthquakes is distinctly and essentially associated with the location of the known fault zones of Northern Thailand. However, some of smaller than magnitude 1, which can be considered to be the back-ground earthquake, do not relate to any lineament on ground surface. The study can also be concluded that the most seismically active area in the Northern Thailand is located between latitude 17$^๐$0’00”- 20$^๐$30’00”N and longitude 97$^๐$0’00”- 101$^๐$30’00”E. The result of the study improve the location of seismicity and provide better understanding of seismotectonic of the Northern Thailand.

KEYWORD: Seismicity, active faults, earthquake relocation, northern Thailand.

Speaker: SUTHASINEE ANUSORNHIRUNKARN (Department of Earth Sciences, Faculty of Science, Kasetsart University, Kasetsart University)

320 Non-contact capacitive sensor for measurements of soil moisture profiles

We present a home-built sensor for measuring the soil moisture along the depth. The sensor is constructed as a vertical stack of hollow cylindrical capacitive probes, each of them separated by very thin insulators. For long-term usage purposes, the probes are equipped in a plastic tube so that they are not contact to the soil samples. At each depth position, the soil moisture is measured by a couple of probes which act as a capacitor whose dielectric material is the soil. Each capacitor is a component of an electronic circuit oscillator whose oscillating frequency depends on the capacitance which in turn altered by the soil moisture.

Speaker: Mr Nakorn Kumchaiseemak

321 Non-Minimal Derivative Coupling Gravity in Palatini Formalism: Scalar Field Phase Portraits

We present and analyze phase portraits of dynamical scalar field of Non-Minimal Derivative Coupling Gravity model in Palatini formalism.

Speaker: Somphoach Saichaemchan (Naresuan University)

322 Observation of GEO Satellite Above Thailand’s Sky

This study did observation of Geostationary Equatorial Orbit (GEO) satellite above Thailand’s sky by 0.7-meter telescope at Inthanon Mountain, Chiangmai, Thailand. The observation took place 14 nights with Sidereal Stare Mode (SSM) in which the moving object will show during the streak detection. The star identification for image calibration is based on a star catalogue. The streak detection of the satellite used matched filter and the extraction of celestial coordinates of the satellite as predicted position. Finally the orbital elements for each satellite was determined.

Speaker: Kanpatom Kasonsuwan (Graduate School, Chiang Mai University, Chiang Mai, Thailand)

323 On the $\lambda$-extended class of the canonical transformations

A new type of canonical transformations for the multiplicative Hamiltonian, which considered as a 1-parameter: $\lambda$-extended class from the standard additive form of the Hamiltonian, was found and called $\lambda$-extended class of the standard canonical transformations. The $\lambda$-extended canonical transformations could be treated as a generating function to produce an infinite hierarchy of the 4 standard types of the canonical transforms.

Speaker: Mr Saksilpa Srisukson (Sarasas Ektra School)

324 Orbital Shapes of Asteroids in Cometary Orbits based on 0.7m Telescope Imaging

The study of orbital element of Asteroids (in Cometary Orbits, ACO) is based on images taken by 0.7 m diameter telescopes to find position of asteroids and calculate their orbital elements. This work focuses on variation of position and orbit shape of ACO, which are obtained by analyzing orbital element and Minimum Orbital Intersection Distance (MOID). Each observation, those parameters are affected by the gravity from Jupiter on ACO. The accuracy of single site data is calibrated by comparing the result from this work with other observations in Minor Planet Center database.

Speakers: Mr Sittiporn Dueantakhu (Graduate School, Chiang Mai University, Chiang Mai, Thailand), Dr Suwicha Wannawichian (Department of Physics and Material, Chiang Mai University, Chiang Mai, Thailand)

325 Peltier Effect Based Temperature Controlled System for Dielectric Spectroscopy

The temperature control system was designed and built for application in dielectric spectroscopy. It is based on dual-stage Peltier element that decreases electrical power and no cryogenic fluids are required. A proportional integral derivative controller was used to keep the temperature stability of the system. Temperature of the system was measure by a Pt100 temperature sensor. Effect of vacuum isolation and water cooling on accuracy and stability of the system were also studied. With incorporation of vacuum isolation and water cooling at 18 °C, temperature of the sample under test can be controlled in the range of -40 °C to 150 °C with uncertainty ± 0.02 °C.

Speaker: Mr Teepkorn Mukda (Kasetsart University)

326 Phase Transformation, Surface Morphology and Dielectric Property of P(VDF-HFP)/MgCl$_2$•6H$_2$O Nanocomposites

Nanocomposite piezoelectric films based on the blend of poly(vinylidenefluoride-hexafluoropropylene) (PVDF-HFP) and magnesium chloride hexahydrate (MgCl$_2$•6H$_2$O) have been investigated in this work. The films incorporated with 0.5 wt% MgCl$_2$•6H$_2$O were prepared using a solution casting technique and uniaxially stretched at various ratios from 2 to 6 times in order to characterize phase transformation, surface morphology and dielectric behavior. The piezoelectric $\beta$ phase transformation and crystallinity of the stretched films were identified by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). A scanning electron microscopy (SEM) was conducted to observe the surface microstructure and porosity. The frequency dependence of dielectric properties was also measured by LCR meter at room temperature. The stretched films show the larger the stretching ratio, the greater the microdefects appear. This leads to a decrease of dielectric constant with stretching ratio. Nevertheless, the P(VDF-HFP) nanocomposites with stretching ratio of 4 times display a higher $\beta$ phase fraction of 90% than the unstretched films. Thus, this result points out that the $\beta$ phase transformation of the composite films can be enhanced by mechanically stretching process.

Speaker: Ms Jureeporn Yuennan (Department of Physics, Faculty of Science, Prince of Songkla University)

327 Phase Transition and Electrical Properties of CaCO3 Prepare by Precipitation Method.

This report studied the necessary condition to obtain different phase of synthesized CaCO$_3$ and their corresponding electrical properties. The precipitation with varied reaction temperature was performed, and the structure of product was determined by using x-ray diffraction and scanning electron microscope. The micrograph of derived CaCO$_3$ was observed as rice-grain structure as reaction temperature was raised up to 80$^o$C, while the XRD pattern of 80$^o$C sample was perfectly matched with pure vaterite (JCPDS no.00-024-0030). According to a complex impedance analyzer investigation in the frequency range of 1.0-10$^5$ Hz, a decrease in the electrical conductivity with increasing reaction temperature was observed. Therefore, the results suggested that the purified vaterite CaCO$_3$ which is the most primitive structure can be obtain as reaction temperature is increased up to 80$^o$C. In this study shows that, the electrical properties and phase transition of CaCO$_3$ powder are depend on the reaction temperature.

Speaker: Sayamon Kaewsopa (045452658)

328 Phonon frequencies, Born effective charges and LO-TO splitting of Mg-IV-N$_2$ semiconductors

Mg-IV-N$_2$ semiconductors, with the group-IV (Si, Ge, and Sn), are alternative materials beside a series of III-N, e.g. AlN, GaN and InN, which is used widely for optoelectronic devices. This work presents phonon frequencies, Born effective charges and longitudinal optical - transverse optical (LO-TO) splitting of these compounds at gamma point by using the density-functional perturbation theory. We employ the norm-conserving pseudopotential within the generalized gradient and the local-density approximation as implemented in ABINIT package. The results are compared with Cd-IV- N$_2$ and Zn-IV- N$_2$ semiconductors to predict the phonon property trend of II-IV- N$_2$ series.

Speaker: Mr Chaiyawat kaewmeechai

329 Photometric Data to Derive an Hertzsprung - Russell Diagram for the Spectral Types of Open Cluster M35

In this paper, we present using photometric data study to derive an Hertzsprung - Russell (HR) diagram for the spectral types of open cluster M35 (NGC 2168). Astrophotography data of M35 observation with a telescope prompt 8 at Chile. Download 10 photo images data of the blue and visual filter from Skynet Catalog, then the photos will be reduction to eliminate noises in order to use stack images of stars matching by the Maxlm DL5 program. All photo images to measure the photometry of the star with Aperture Photometry Tool program. The distance modulus (V-M$_\text{v}$) and the distance to star cluster (d) were obtained and compared for the main sequence turn off point of an HR diagram. The color index (B-V) and the absolute magnitude (M$_\text{v}$) were calculated the effective temperature (T$_\text{eff}$), luminosity (L), radius (R), mass (M) and age (t) of the stars of the cluster. The physical properties of star cluster were determined, that can be identified the spectrum types of stars of open cluster M35.
The results photometric solution shows that with an HR diagram illustrate that the distance modulus of 9.60, the distance to star cluster of 832.34 parsec, the average effective temperatures of 5313.268 K, the average luminosities of 0.743L$_\text{sun}$, the average radiuses of 0.847R$_\text{sun}$, the average masses of 0.743M$_\text{sun}$ and the average ages of 137.87 t$_\text{sun}$. The spectral types of stars of open cluster M35, most of spectral type G and K, which is a main sequence with similar luminosity and temperature of the sun.

Speaker: Patapong Panpiboon

330 Photometric Investigation of Novae T Pyx, BT Mon and V574 Pup

Recurrent novae (RNe) are novae with multiple recorded outbursts powered by a thermonuclear runaway. This occurs on the surface of the white dwarf in a close binary system in which a late type main-sequence or giant secondary star is filling its Roche lobe and transferring material onto the white dwarf primary star. They resemble classical novae (CNe) outbursts in several aspects and by definition, certain of CNe will join the class of RNe when a second major outburst is recorded. RNe play an important role as one of the suspected progenitor systems of Type Ia supernovae (SNe) which are used as primary distance indicators in cosmology. Thus, it is important to investigate the nature of central binary systems of CNe and RNe to determine the relation between the parameters of the central system and outburst type and finally ascertain the population of objects that might ultimately be candidates for Type Ia SNe explosions. The proposal that RNe occupy a region separated from CNe in an outburst amplitude versus speed class diagram was adopted. Since the low amplitude results from the existence of an evolved secondary and/or high mass transfer rate in the quiescent system, RNe candidates should accordingly have low amplitude. The catalog of 93 novae with observed V amplitudes given in the literature was used to select the target novae suspected to be RNe candidates via spectroscopic investigation. We selected 3 preliminary targets including T Pyx, BT Mon and V574 Pup which are suspected RNe candidates based on their low amplitudes and their visibility. We obtained their magnitudes at quiescence using ULTRASPEC spectrograph on the 2.4-m Thai National Telescope. The plots of targets on near-infrared CMD suggest that all three should have main-sequence secondary stars. This is true for T Pyx, whose secondary star has been confirmed spectroscopically to be a main-sequence star, but not yet confirmed for BT Mon and V574 Pup.

Speaker: Dr Farung Surina (Chiang Rai Rajabhat University)

331 Position Change of the Moon to showing the Lunar Mansion’s Pattern

This research was conducted to find out the pattern of the lunar mansions from the position change of the Moon. These positions were called as the lunar mansions. The lunar mansions have 27 groups with important 27 fixed stars. The Moon’s position was calculated from nearby stars by cosine formula. The smallest angular separation between the Moon and the fixed stars was the lunar mansion of the day. The graph relate with the date from 2011-2030 and the lunar mansions was showed the lunar mansion’s pattern. It was found that the lunar mansion’s pattern was a linear equation as y = (0.9882x + 15.4192) $\pm$ 0.4318.

Speaker: Mr Adisak Sukwisoot

332 Potential Increasing of Rubber Sheet Production with Fungus Displacement by Solar Tunnel Dryer.

In this study, Potential increasing of rubber sheet production with fungus displacement by solar tunnel dryer. By integrating a biomass gasifier as an assisting heat source for drying Rubber Sheet produce and its performance analysis has been investigated. Experimental study has been carried out with the stand-alone solar tunnel dryer and the dryer with the assisted biomass gasifier.
For thermal performance analysis, for wind speed 1.0 m/s , the dryer with assisted gasifier gave an average efficiency of 32.86% higher and the drying period was 31.45 % shorter than those of the unit without the gasifier. For wind speed 1.5 m/s, and for wind speed 2.0 m/s, the values are 21.49 %, 28.68 % and 33.17%, 24.54 %, respectively. From economic analysis, drying of wind speed 1.5 m/s is the most appropriated. The payback and the IRR were 1.8 years and 55.48 %, respectively. While those for wind speed 1.0 m/s were 2.74 years and 36%, respectively.

Speaker: Duangkamol Dungphontong (Program of Engineering Management, Faculty of Engineering,Rajabhat MahaSarakham University)

333 Preheating in disformal inflation

We study the preheating process in the universe after inflation for the inflationary model in which the coupling between the inflaton and the matter scalar field is a result of disformal transformation. We find that the disformal coupling between inflaton and matter scalar field can lead to efficient preheating process.

Speaker: Dr Khamphee Karwan

334 Preparation of Platinum (Pt) Counter Electrode Coated by Electrochemical Technique at High Temperature for Dye-sensitized Solar cell (DSSC) Application

Platinum (Pt) counter electrode was coated by electrochemical method as high surface area and abiding adhere to substrate. Electrochemical system consist the dc power supply control, heating to electrolyte solution and substrate holder can adjust distance of electrode. Electrolyte solution was synthesized by platinum (IV) choloride (PtCl$_4$) powder (purity, 99.9 %) dissolved in hydrochloric acid solution (HCl, 0.00156 M, purity of 99.99 %). The Pt films were deposited on the FTO substrate. Electrolyte concentration and the distance between positive and negative electrode (2 cm) were fixed under stir with magnetic stirrer continuously. The deposition time of 10, 30 and 60 minutes, the coating current of 5, 10, 15 and 20 mA and temperatures of 25, 30 and 40$^°$C, respectively were varied. The surface morphology and optical properties of the Pt film was analyzed by digital microscopic and UV-vis spectrophotometer. Results, the Pt films exhibit uniform surface area highly for the conditions the coating current of 5, 10, 15 and 20 mA, the deposition time of 30 and 40 minutes at 40$^°$C. Transmittance values of Pt films deposited on FTO substrate has approximately of 5 to 50 % show that occur high reflection corresponding to dye molecule absorption increases. DSSC device was fabricated from the TiO$_2$ standard and immersed in dye-sensitizer (N719) for 24 hours. After, the TiO$_2$ working electrode complete sandwich the Pt counter electrode and injected iodide electrolyte solution. The efficiency of DSSC cell was measured by solar simulator (AM 1.5). Efficiency value obtains as high as 5.91 % for the coating current, deposition time and solution temperature of 15 mA, 30 minutes and 40$^°$C, respectively. Summary, influence of temperature effects efficiency increasing. Pt counter electrode coated by chemical method can be prepared easily and the suitable usefully for DSSC application.

Speaker: Mr Tanachai Ponken (Program of Physics, Faculty of Science and Technology, Rajabhat Mahasarakham University)

335 Principle chiral models and integrable systems

Principle chiral models and their deformations are interesting systems with QCD-like behaviour. Furthermore, their integrable structure makes them potentially tractable. I discuss quantum mechanical theories arising in various limits of the models, with a view to analysing the non-perturbative dynamics.

Speaker: Dr Benjo Fraser (Chulalongkorn University)

336 Production and Ratio Analysis for The Production of Charcoal Briquettes from Bamboo(Dendrocalamus Asper Backer)

The bamboo is highest growth rate plant in the world. Bamboo can grow 10 cm. in the days. Moreover it is environmental friendly and easy to regrow. Research studies founded spicy with high energy, drought resistance, can withstand flooding and suitable for growing in Thailand is ‘Dendrocalamus Asper Backer Bamboo’

The purposes of this study were found the best ratio of fuel briquettes from Dendrocalamus Asper Backer Bamboo to investigate and compare briquettes with other biomass fuel about heat rate, time and strength. This project was experimental and qualitative research with ratio of charcoal powder and cassava powder in 100:0, 95:5, 90:10, 85:15, 80:20, 60:40, 50:50. And compress together to briquettes in pentagon shape size 5cm. width diameter x 5cm. length and center hole is 1cm. diameter. So data was analyzed using 3 prices of each ratio to boil water in 1000ml. and record temperature by computer. After that, Choose 3 ratio for analyzed with Thermal Gravimetric Analyszer (TGA) and physical test machine for accurate results.

The results of the study were as follows the best ratio of charcoal from Dendrocalamus Asper Backer Bamboo power and cassava powder to briquettes is 85:15

Speaker: Mr Ratchatapong Lukmuang

337 Properties of Dried Cultivated Banana Using 3-Shelves Solar Oven

Abstract
This research is studying dried banana. Using solar drying greenhouse. To compare the rate of drying Weight loss, Humidity and wet. Materials used in the experiments is Cultivated Banana. Banana Full ball and banana cut in half. The experiment compared to dry naturally with using 3-Shelves Solar Oven for a period of 3 days from the time. 09:00 to 16:00 hrs. Which records the temperature every 30 minutes, the average temperature in the incubator is higher than the ambient temperature. For drying the third floor that the rate of drying banana full ball shown maximum 1.70 grams per hour. Banana and half in the second floor shown maximum rate of drying 1.58 grams per hour. And determining the moisture content of the wet bananas of cut in half in second floor shown minimum of 12 hours and banana full ball shown minimum of 14 hours on the standard wet equal to 22 percent of drying house. The second floor is the best for drying.

keywords: Cultivated banana solar dryers moisture standard wet

Speaker: Ms leeming sofia (Authors)

338 Properties of Pre-main sequence stars in young star cluster NGC 2175

Young star clusters harbor a large number of stars in pre-main-sequence (PMS) stage of their evolution. Physical properties of these stars can be constrained using various astrophysical techniques (e.g. by plotting them on HR diagram, studying their spectral energy distribution, times series photometric analysis, spectral studies, etc.). In this work we present preliminary time series photometric analysis of stars in young star cluster NGC 2175. Light curve analysis is used to detect variable stars in the cluster. We cross-match the present photometric catalog with young stellar objects (YSOs) catalogue from the literature. We compare the rotation period of variables with their ages and masses and try to understand and interpret the underlying physics.

Speaker: Mr Siwarut Ploydang

339 Quantum Oscillation of Conductance and Negative Tunneling Magnetoresistance in Velocity-Modulated Graphene Spin-Valve Device

Mismatch effect of renormalized Fermi velocity of massive Dirac fermions on the spin transport properties and tunneling magnetoresistance in a gapped graphene-based ferromagnetic/velocity barrier/ferromagnetic (FG/VB/FG) junction is investigated. The electrostatic potential created by the applied voltage on the VB region can generate spin-dependent collimation of Dirac fermions. The quantum beating pattern in the spin conductance oscillation are shown as a function of the Fermi energy at low velocity ratio (the Fermi velocity inside the barrier to that outside the barrier). The Fermi-velocity mismatch effect between graphene junction give rises to the oscillating behavior of negative tunneling magnetoresistance at the velocity ratio less than one.

Speaker: Mr Husnul Fuad Zein (Student)

340 Quasinormal Modes of a Massless Charged Scalar Field in the 3+1 Dimensional AdS Reissener-Nordstrom Spactime.

Abstract

The quasinormal modes(qnm) of a massless charged scalar field in the 3+1 dimensional anti de Sitter(AdS) Reissener-Nordstrom(RN) spacetime are analytically calculated. The solutions of the scale field under the influence of the RN black hole are approximated by satisfying the boundary conditions at the horizon and the far away zone from the black hole. Our result for the small black hole mass is consistent with the numerical result.

Keywords: Quasinormal modes, Quasinormal frequencies, AdS black holes, Reissener-Nordrom black holes

Speaker: panapol kanjanaphomchom

341 Radio Frequency Interference Site Survey for Thai Radio Telescopes

Radio astronomical observations have increasingly been threaten by the march of today telecommunication and wireless technology. Performance of radio telescopes lies within the fact that astronomical sources are extremely weak, e.g more than 15 orders of magnitude weaker than most mobile phones. The National Astronomy Research Institute of Thailand (NARIT) has initiated a 5-year project, known as the Radio Astronomy Network and Geodesy for Development (RANGD), which includes the establishment of 40-metre and 13-metre radio telescopes. Possible locations have been narrowed down to three candidates, situated in the Northern part of Thailand, where the atmosphere is sufficiently dry and suitable for K and Q band observations. The Radio Frequency Interference (RFI) measurements were carried out with a DC spectrum analyser and directional antennas at 1.5 metre above ground, from 20 MHz to 6 GHz with full azimuth coverage. The data from a 3-minute pointing were recorded for both horizontal and vertical polarisations, in maxhold and average modes. The detection threshold is approximately 80 dB(W/m^2/Hz) higher than the recommended RFI level at L band for radio astronomical observation by the International Telecommunication Union (ITU-R RA.769-2). The results, for which we used to make preliminary site selection, show signals from typical broadcast and telecommunication services and aeronautics applications. The signal intensity varies accordingly to the presence of nearby population and topography of the region. More RFI measurements at the best candidate are being planned.

Keyword – astronomy radio telescope interference survey narit

Speaker: Dr Phrudth Jaroenjittichai (National Astronomical Research Institute of Thailand)

342 Rainfall Estimation from Radar in different seasons over Northern Thailand

Abstract
Thailand was under the influence two types of monsoon winds, Northeast monsoon and Southwest monsoon. The Northeast monsoon (October – February) brings the cold and dry air from China to cover the major parts of Thailand. The Southwest monsoon (May – October) brings a stream of warm moist air from Indian Ocean towards Thailand causing abundant rain over the country. The objective of the research is to evaluate Z-R relationship (Z = aR^b) for rainfall estimation in different monsoons.
This study use reflectivity data from Omkoi radar station in Chaing Mai Thailand and rainfall data in radius of 240 km (42 stations) from Omkoi weather radar station from Thai Meteorological Department in 2015. Method for matching reflectivity data (Z) and rainfall rate (R) relationship are PMM (Probability Matching Method) and Statistics comparison by RMSE (Root Mean Square Error), correlation coefficient and scatter plot of mean radar rainfall and mean gauge rainfall. We find that the Z-R relationship in rainy season (May – October) is Z = 103.83R^1.5082 and the Z-R relationship in non- rainy season (November – December, January – April) is Z = 102.18R^1.4512 . For the same rainfall intensity, reflectivity value in non – rainy season is higher than in the rainy season. Considering the statistics and graphs distribution.
It is obvious that the correlation coefficient in the rainy season are higher than during the non- rainy season. This research shows that each monsoon causes a different type of rain. Thus rainfall estimation for each monsoon should be based on different Z-R relationship for more accuracy.

Key-word: Rainfall, Z-R Relationship, Monsoon, Radar, Rainfall estimation

Speaker: Ms Papatsorn Aumjira (Department of Earth Science, Faculty of Science, Kasetsart University)

343 Reduction of delamination for MSOP Package in die attach process for integrated circuit package

Delamination is a mode of failure for composite different materials and can cause layer to separate between silicon die and die attach material. Because there is a mismatch in the thermal of materials, lead to cracking and damaging on integrated circuit (IC) packages. In this study, we attempted to reduce the delamination of mini small outline package (MSOP) in die attach process. The roughened leadframe was treated by micro-etching method (ME version2), and then was plated with Ni/Pd/Au on copper base materials (known as PPF+ME2). The bond line thickness was controlled in the range 0.5-1.0 mil and also designed the experiment of cure profiles. The curing time was rapidly ramped up from existing temperature to 175 Celsius by 10 min and comparing with ramp up time by 30 min. The delamination inside the IC package was investigated by scanning acoustic microscope (SAM) after reliability test. The results shown that total curing time at 90 min (ramp up time to 175 Celsius by 30 min) and bond line thickness setting greater than 0.5 mil didn’t show delamination. Finally, we can confirm that the delamination risk was reduced and IC package can be used in the temperature range of -65 Celsius to 150 Celsius.

Speaker: Ms Tawika Buntam

344 Reduction of setup time in wafer sort process before integrated circuit packaging

The purpose of this research aims to reduce of setup time in wafer sorting before integrated circuit packaging. To add hardware respectability detection process without prober setup before correlation wafer check process with modification of test program and making up a tool kid. Then, the experimental data was correlated with the respect range. Finally, this setting up was limited that it will be the reference for detection of respectability functioning test hardware. The results showed that the tool achieves for test hardware respectability detection. By our methodology, it will apply to other wafer test hardware and it could clearly reduce wafer sort setup time.

Speaker: Mr Pannawat Watthakeehuttakum

345 Removal of hydrogen sulfide (H2S) from biogas for the community in the province of Maha Sarakham

Biogas produced from the fermentation in the province of Maha Sarakham of excreta from cow dung, fattening pigs and buffalo dung in small scale farms contained hydrogen sulfide (H2S) at 764, 926 and 1,103 ppm, respectively. This gas has offensive smell and is corrosive to motor and metal stove of farmers, thus needs to be eliminated. The adsorbent granules soaking in FeCl3 and NaOH made from grey cement mixed with diatomaceous earth or fine sand. The experiment cow dung, fattening pigs and buffalo dung farms revealed that the adsorbent granules made from fine sand mixed with grey cement had better efficiency in reducing H2S than diatomaceous earth plus grey cement or scrap iron (97.1-91.4 vs. 86.0-64.3 and 77.9-89.4%, P<0.01). The reduction of H2S increased with the increasing weight of the adsorbent tanks, made from fine sand mixed with grey cement, from 2 to 4 and 6 kg (84.1-89.2 to 92.7-98.0 and100-99.1%, respectively). Adsorbent set of 6 kg weight can reduced H2S in biogas from 2,141 to 0 ppm in the first day and to 6 ppm onday 25 of using period, during which the color of adsorbent granules changed from red brown to dark brown.

Speaker: Mr Wasan Pinate (Program of Physics, Faculty of Science,Rajabhat MahaSarakham University)

346 Riceberry Grain Standardization Based on Color Distribution and Shape Parameters

Riceberry is a highly nutritious rice variety with dark purple grain. Previous studies have shown that the darker shade of grain color has a higher nutrient content. In this work, we study the color distribution of the Riceberry rice grains in order to provide a quantitative quality indicator. Here, pictures of the grains were taken using a digital CCD camera. To make the data more understandable, we extracted RGB data from the grain images and converted them to HSV color space. Color distributions and shape parameters of pixels, such as mean, standard deviation, skewness, and kurtosis, were analyzed. Based on the peaks and tails positions of hue distributions, the grains can be classified into 3 categories: (1) the maxima at hue $\approx$ 0.9 – 1.0 with left tail corresponding to dark purple grain; (2) the maxima at hue $\approx$ 0.9 – 1.0 with right tail corresponding to light brown or red grain; and (3) the hue scattered between 0.9 – 1.0. These results can be used to standardize the grain color, which is very useful for adding value to the Riceberry rice products.

Speaker: Ms Khotchakorn Kaisaart (Department of Physics, Faculty of Science, Kasetsart University, Bangkok 10900, Thailand)

347 Role of ilmenite micro-inclusion on Fe oxidation state of natural sapphires

The blue color of the blue sapphire is caused by the Fe-Ti pairs. Recently, the oxidation states of Fe and Ti on high-quality blue sapphire were found as Fe$^{3+}$ and Ti$^{4+}$. However, the oxidation state of Fe on natural sapphire with some inclusions was reported as mixing of Fe$^{2+}$ and Fe$^{3+}$ using the x-ray absorption near edge structure spectroscopy (XANES). Generally, there are mineral inclusions on natural sapphire related to Fe such as hematite (Fe$_2$O$_3$) and ilmenite (FeTiO$_3$). In this study, we investigate the micro-inclusions on natural sapphires by the electron probe micro analyzer (EPMA). The oxidation states of Fe and Fe-O bond length were analyzed by x-ray absorption spectroscopy (XAS). The Fe K-edge EXAFS fitting results focused on the first shell of Fe atoms on high-quality natural sapphires were shown that the Fe-O bond length on α-Al$_2$O$_3$ was fitted well with Fe-O bond length on Fe$_2$O$_3$ presenting Fe$^{3+}$. However, the Fe-O bond length on natural sapphires with ilmenite micro-inclusion was fitted with Fe-O bond length on Fe$_3$O$_4$ showing Fe$^{2+}$ and Fe$^{3+}$. As the result, the Fe$^{2+}$ on natural sapphires was caused by the ilmenite micro-inclusion.

Speaker: Mr Natthapong Monarumit (Kasetsart University)

348 Rotation Curves and Constraints on Dark Matter Annihilation

We have focused on dark matter annihilation into electron-positron pairs, neglecting other processes, such as dark matter decay, or other annihilation products. Instead of focusing on a specific dark matter annihilation model, we have adopted a model-independent approach, in which all particles are created with the same initial energy, of the order of the mass of the dark matter particle. The propagation of the electrons and positrons has been determined by the diffusion-loss equation. We have assumed a uniform diffusion coefficient.
We have considered inverse Compton scattering, synchrotron radiation, Coulomb collisions, bremsstrahlung, and the ionization of neutral hydrogen atoms as the main energy loss mechanisms. We have estimated the contribution of dark matter annihilation to the total gas pressure and considered its effect on the rotation curve. By fitting the 26 rotation curves of low surface brightness (LSB) galaxies , we are able to find the constraints on dark matter particles. We have derived limits on the mass of dark matter particles by applying the effect of the pressure from dark matter annihilation into electron-positron pairs to the rotation curves of LSB galaxies.The limits of the mass of dark matter particles are between 1 GeV to 30 GeV.

Speaker: Dr Maneenate Wechakama (Kasetsart University)

349 Schiff Base modified on CPE electrode and PCB gold electrode for selective determination of silver ion

The Schiff base was synthesized by 2,5-thiophenedicarboxaldehyde and 1,2,4-thiadiazole-3,5-diamine with condensation method. There was modified on Carbon paste electrode (CPE) and Printed circuit board (PCB) gold electrode for determination silver ion. The Schiff base film of modified electrodes was characterized by atomic force microscopy (AFM) and scanning electron microscopy (SEM), respectively. The electrochemical study was reported by cyclic voltammetry method and impedance spectroscopy using modified electrode as working electrode, platinum wire and Ag/AgCl as counter electrode and reference electrode, respectively. The modified electrodes have suitable detection for Ag+. The determination of silver using the modified electrodes depended linearly on Ag+ concentration in the range 1x10-10 M to 1x10-7 M, with cyclic voltammetry sensitivity were 2.51x108 µAM-1 and 1.88x108 µAM-1 for PCB gold electrode and CPE electrode, respectively, limits of detection were 5.33x10-9 M and 1.99x10-8 M for PCB gold electrode and CPE electrode, respectively. The modified electrodes have high accuracy, inexpensive and can applied to detection Ag+ in real samples.

Speakers: Ms Piyawan Leepheng (College of Nanotechnology, KMITL), Dr Darinee Phromyothin

350 Schwinger pair creation in graphene wormhole

We investigate the behavior of Dirac Particle (electron and hole) confined on the surface of graphene wormhole, specifically, curvature induced by the geometry of graphene wormhole.
For calculation, we use numerical shooting method of finding eigenvalue of the Dirac equation in a curved space of graphene wormhole.

Our numerical results demonstrate that energy of band structures of the particle depend on the geometrical parameters of graphene wormhole
and appear to the periodic spin-orbit potential, corresponding to Zeeman effect.

The geometrical parameters and quantization of momentum in the circumference direction specify a quantum state of particle as a bound state particle or a unbound state particle.
Finally effects of the geometrical parameter of graphene wormhole on the Schwinger pair creation of particle are presented.

Speaker: Mr Trithos Rojjanason (Kasetsart University)

351 Simple system to measure Seebeck effect coefficient at room temperature

A system for measuring Seebeck coefficient has been designed and constructed which can be measures at room temperature. The system consists of three main parts, a temperature controlling, a data acquisition and a programming. The temperature controlling include of a PID temperature controller which fabricated by using an Arduino microcontroller boards. The data acquisition consists of two type-K thermocouple for measures hot side and cool side temperature of the system and a Seebeck voltage measuring circuits for detected the voltage which generated from a thermoelectric materials. The programming part was developed on personal computer for monitoring temperature and Seebeck voltage and controlling the hot side temperature of the system during measuring. The hot side temperature was controlled with the range of 25 to 150 Celsius degrees. The hot side and the cool side temperature were measured with the range of 25 to 500 Celsius degrees and have the resolution of 0.01 Celsius degrees. The Seebeck voltage was detected with the resolution of 1 microvolt by using the fabricated circuits. The developed program was displayed a graph of the voltage with the temperature difference between hot side and cool side. This part was controlled the temperature range of the hot side temperature and real time showed the temperature and the voltage. The Seeback coefficient was evaluated and displayed when the data collects was finished.

Keyword : Thermoelectric materials, Seebeck effect, Seebeck voltage.

Speaker: Mr Angmanee Bundasak (๊Ubon Ratchathani University)

352 Simulation and Design of Electron Beam Irradiation System for Natural Rubber Vulcanization

Electron beam irradiation can modify or improve chemical and physical properties of polymer and natural rubber. It is one of interesting and effective industrial applications of electron accelerators. This paper describes about the design of electron beam irradiation apparatus to find the efficient and convenient system for the natural rubber vulcanization. In addition, electron beam penetration dose in natural rubber latex was studied by using the Monte Carlo program GEANT4. Electron beam with different energy can penetrate deeper in the materials and give higher electron beam dose. Thus, our electron linear accelerator can produce electron beam with adjustable energy in the range of 0.5-4 MeV. The maximum electron dose at the accelerator exit is expected to be about 640 Gy. This research focuses on using program GEANT4 to simulate the electron depth dose distribution after radiating the rubber latex with electron beam. The results from simulation can be used to optimize the important parameters include both electron beam and material properties, which are electron beam energy, electron current, amount and uniformity of electron dose as well as the structure, thickness and density of material.

Speaker: Ms Kittiya Kosaentor (Chiang Mai University)

353 Simulation and Experimental Study of Bipolar Plates on The Performance in PEM Fuel Cell

This research is a simulated and experimental study on effects of bipolar electrodes of a PEM fuel cell on its power conversion efficiency. The PEM fuel cell structure consists of bipolar electrodes, proton exchange membrane with catalysts, flow channels of gases. This research used fuel cell of 49 $cm^2$ in active area as a research sample and the Comsol 4.4 was employed to simulate flow channels which are serpentine pattern for anode and parallel pattern for cathode. The parameters used were channel height of 0.10, 0.15 and 0.20 cm, gas pressure of 0.5, 1.0 and 1.5 atmosphere and cell temperature of 50, 60 and 70 celsius and then calculated effects of such parameters using Comsol 4.4. After the calculation has been completed, the prototype of the PEM fuel cell were fabricated using graphite plate as electrodes which had the channel height of 0.20 cm, proton exchange membrane using carbon-platinum catalyst. Finally the prototype was tested under condition of 50 celsius in cell temperature and 1.0 atmosphere in gas pressure.
In part of calculation using Comsol 4.4, it showed that the PEM fuel cell comprising anode which has serpentine pattern as gas flow channel and anode which has parallel pattern of gas flow channel and operated under 70 celsius in temperature exhibited the highest power conversion efficiency since channel width is 0.30 cm, channel separation is 0.20 cm, radius of curvature is 0.40 cm for anode and for cathode, it has 8 channels, channel width is 0.50 cm, width of channel end is 0.30 cm, channel height is 0.20 cm. further it was found that the effect of temperature on the power conversion efficiency is not severely. And for anode, the concentration of hydrogen gas was reduced 64 w% due to the reaction whereas in parallel channel of cathode the oxygen concentration was reduced by only 6 w% from 23 w% at the entrance to 17 w% at the end. The maximum power output of the prototype operated under such condition was 0.28 W/$cm^2$ calculated from maximum power output voltage (Vmp) of 0.70 V and maximum power output current density of 0.42 A/$cm^2$ which was in good agreement with that simulated using Comsol 4.4 which revealed the power output of 0.29 W/$cm^2$.

Speaker: Mr pornchai chinnasa (Rajabhat Mahasarakham University)

354 Simulation of Wind Speed and Wind Direction over Urban Structures

In this study, the effect of urban structures (e.g. buildings, trees, bridges, etc.) on surface wind speed and wind direction was investigated using a Navier-Stokes equation solver to simulate wind over complex topography. The simulations were performed over the Lampang-Ngao highway and surrounding areas in Amphoe Muang Lampang in Thailand. This area is characterized by vehicular traffic emissions that affect communities living beside the highway. Since wind speed and wind direction affect the concentration of these emissions, this study is a first step to determine the location where to plant more trees to improve the air quality in urban areas.

Speakers: Mr Natthawut Wongjanta (Lampang Rajabhat University), Ms Natnicha Thamcharoenrat (Lampang Rajabhat University)

355 Solar energetic particle propagation from solar flare

Solar flare is the huge explosion on the Sun’s surface and releases the solar energetic particles (SEPs) to interplanetary medium.The objective of this work is studying the propagation of SEPs from the Sun to the Earth. We simulate the particle propagation for the solar event on August 9, 2011 with the transport equation of Ruffolo 1998. We solve the transport equation by the numerical technique of finite different method. We find injection durationby fitting the simulation results and the particle data from spacecraft. The X-ray class of the selected solar event is X6.9, the solar flare position on the Sun is N18W68, and the solar wind speed is 551.5 km/s. We found the solar flare on August 9, 2011 is the gradual flare. This flare had the long injection time from the Sun to the Earth corresponding to the shock wave detected after explosion in the interplanetary space 13 minutes. In the path of the solar flare affected on the Earth, the Kp-index (the value of the earth’s magnetic field variable) was considered. The Kp-index of these solar flares was less than 3, which they didn’t affect on the Earth.

Speaker: Mr Phichayoot Baisri (Department of Physics, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand.)

356 Stress-Strain Measurement of Rubber with Optical Moiré Fringes

We use the Moiré fringe patterns to measure the stress and strain values of rubber in tension, and analyze the stress-strain relationship. With the printed straight-line pattern on a standard dog-bone specimen, the Moiré patterns can be constructed when the rubber specimen is stretched. The geometrical relationship of bright and dark fringes is used to calculate the strain values both in the axial and transverse directions. Together with optical images for cross-section measurement, we can measure true stress and strain values, and determine the homogeneity of such values simultaneously. This true stress-strain relationship is different from the typical engineering stress-strain relationship in the sense that the latter is calculated from the fixed initial cross-section area of the specimen. When compared with the standard engineering measurement, the results from the Moiré method exhibit the same trends in the stress and strain values, and the stress-strain relationship is in good agreement in the linear elastic regime. More importantly, the Moiré method can provide direct measurement results of the true stress-strain relationship.

Speaker: Mr Watthana Sriklin (Optical and Quantum Physics Laboratory, Department of Physics, Faculty of Science, Mahidol University, Bangkok, 10400 Thailand)

357 Structural and optical properties of mercury chalcogenide HgSxSe1-x and HgSxTe1-x nanocrystals: Atomistic tight-binding theory

The structural and optical properties of the mercury chalcogenide HgSxSe1-x and HgSxTe1-x nanocrystals with zinc-blende structure are analyzed using the sp3s* empirical tight-binding method. We calculate the single-particle spectra, band gaps, charge densities, density of state (DOS), electron-hole interaction and optical properties as a function of diameters and alloying concentrations (x). The computations highlight that these natural properties are sensitive with diameters and alloying contents (x) of HgSxSe1-x and HgSxTe1-x nanocrystals. Finally, the scheme is expected to provide the detailed information in electrical and optical properties of HgSxSe1-x and HgSxTe1-x nanocrystals with the aim to implement them as the novel nanoelectronic devices.

Speaker: Mr Adulvit Chuaephon (Ubon Ratchathani University)

358 Structural and Vibrational Properties of GaAsN Films grown by MOVPE with a Partial Nitrogen Carrier Gas

The Metal Organic Vapor Phase Epitaxy is single crystal growth process, forming GaAsN films on GaAs (001) substrates, built up by chemical method using trimethylgallium (TMGa), dimethylhydrazine (DMHy) and tertiarybutylarsine (TBAs) as Ga, N and As, respectively. Commonly, the process is contained hydrogen (H$_2$) gas, a carrier gas, to convey precursor to the reaction chamber. Alternatively, nitrogen gas (N$_2$), attractive representation instead of H$_2$ gas, is non-flammable and it is less thermal conductivity. Structural and vibrational properties of GaAsN (0 < N < 5%) films grown using a mixed N$_2$/H$_2$ carrier gas were characterized by various laser powers of Raman spectroscopy to observe annealed effects in the meantime. To verify effect of an existing of N$_2$ carrier gas during the MOVPE growth of GaAsN films, the growth with two different carrier gas conditions, 100% of H$_2$ carrier gas and 50% of H$_2$ carrier gas mixed to N$_2$ gas were performed. The results show that the films, using a mixed carrier gas, tend to have more nitrogen content than typical one. Although the nitrogen localized vibrational mode (N-LVM) is shifted, it occurs from the other cases, for instance, the penetration depth of laser and the enlargement of lattice size are concerned. As a result, we figure out that increasing of nitrogen content relates to the decreasing of growth temperature, and in addition to laser powers of Raman spectroscopy affect to determine the nitrogen content. By the way, it is found that the laser powers of Raman spectroscopy aren’t enough to arouse the interstitial nitrogen atom to be in lattice point.

Keyword: Metal organic vapor phase epitaxy (MOVPE), carrier gas, GaAsN

Speaker: Mr Teerapat Lapsirivatkul (Department of Physics, Faculty of Science, Chulalongkorn University, Bangkok 10330, Thailand)

359 Structural stability and electronic structures of YH$_2.83$ and ScH$_2.83$

YH$_{2.83}$ and ScH$_{2.83}$ are a defected system in which some interstitial sites of hydrogen atoms are void. We used \textit{ab-initio} method to study their structural stability and electronic structures. The hcp phase of YH$_3$ and ScH$_3$ is used as an initial structures, which composes of 6 metal atoms and 18 H atoms per unit cell. Then, YH$_{2.83}$ and ScH$_{2.83}$ are obtained by removing one of H atoms from the unit cell. The results show that they are dynamically stabilized but not energetically favorable. Their energy gaps are closed by the crossing of the valence band maximum crossing at the Fermi level.

Speaker: TeeRachote PaKornchote

360 Synthesis and characterization of MgO by microwave-assisted thermal oxidation for photocatalytic applications

The magnesium oxide (MgO) nanoparticles were synthesized by microwave-assisted thermal oxidation. The crystal structural, morphology, optical property were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), UV-Vis Spectrophotometry, Photoluminescence (PL) spectra, respectively. It was observed that, the synthesized nanoparticles were well-dispersed nanocube shape. The XRD confirmed the formation of single phase MgO exhibiting face cubic centred structure. Furthermore, the efficiency of MgO nanocube as a photocatalyst for degradation of Eosin-Y under ultraviolet light irradiation were evaluated. It was found that, MgO can used as a sensitizer in photocatalytic application and its photocatalytic activity more than MgO commercial grade. The degradation rate constant increase from 0.0011 per minute to 0.0582 per minute. The results demonstrated that the origin of photocatalytic activity in MgO arises due to the existence of high defects on the surface of MgO.

Speaker: Dr Sanpet Nilphai

361 Synthesis and properties of cobalt ferrite nanoparticles in bacterial cellulose nanofiber scaffold

Cobalt ferrite nanoparticle (NP) is a class of ferrite which has a potential for many applications but the agglomeration of magnetic NPs limits its full potential usage. In this research, cobalt ferrite NPs were synthesized in the presence of bacterial cellulose (BC) nanofibers which acted as the scaffolding templates. The BC was obtained from a commercially available nata de coo (coconut jelly) which was washed and rinsed in water several times before the freeze-drying process was applied. The cobalt ferrite was synthesized by using a coprecipitation method. In the presence of bacterial cellulose, FeCl$_{2}.$6H$_{2}$O and CoCl$_{2}.$6H$_{2}$O at the right stoichiometric ratio were mixed in deionized water. After that, NaOH was added to create the precipitation of cobalt ferrite NPs on the surface of the BC nanofibers. In this experiment, the concentration of chloride salt was varied and the method of BC drying was explored. The X-ray diffraction (XRD) patterns revealed the formation of the cobalt ferrite crystalline structures. The scanning electron microscope (SEM) showed the morphology of cobalt ferrite NPs which formed the nanotube-like structure surrounding the BC nanofibers. The thermal analysis showed the several weight loss characteristics and the thermal stability of NPs in BC scaffold up to 800 °C. The Fourier transform infrared spectroscopy (FTIR) showed the characteristic peaks of O-H and C-O groups. Vibrating sample magnetometer (VSM) was used to study the magnetic properties of cobalt ferrite NPs in BC scaffold. The saturation magnetization was found to be influenced by the initial concentration of Fe and Co ions, and the drying processes.

Keywords: cobalt ferrite; nanoparticles; bacterial cellulose; magnetic properties;

Speaker: Ms Kanchanok Phoophathong (Khon Kaen University)

362 Temperature dependence of graphene and N-doped graphene for gas sensor applications

Micrometre-scale graphene sensors can detect individual molecule adsorptions or desorptions [1]. This is due to its low-noise electronic characteristics. However, molecules in gas phase rarely adsorb on non-defect graphene surfaces. By doping graphene with nitrogen, the atomic structure and electronic properties of graphene were modified. Here, we measured the sensitivity of graphene and N-doped graphene to ethanol vapor as gas sensors with varying concentration of ethanol and temperature of graphene. Graphene was synthesized by chemical vapor deposition on copper foils, and then transferred onto glass slide by chemical etching. N-doped graphene was produced by annealing graphene in ammonia atmosphere. Our results showed the sensitivity of both graphene and N-doped graphene are low, ~1. No significant dependent of sensitivity on concentration of ethanol gas in the range of 25-200 ppm was observed. Sensitivity of graphene increases with temperature from 25 ˚C to 150 ˚C up to 1.2%, but that of N-doped graphene decreases by 2%.

Reference

[1] Schedin, F., Geim, A. K., Morozov, S. V., Hill, E. W., Blake, P., Katsnelson, M. I. and Novoselov, K. S. Detection of individual gas molecules adsorbed on graphene. Nature Nanotech. 6, 652-655 (2007).

Speaker: Rangsan Panyathip (Department of Physics and Materials Science, Faculty of Science, Chiang Mai University)

363 The background evolution in general disformal gravity

We study a subclass of GLPV modified gravity theories generated by a general disformal metric $\bar g_{\mu\nu} = g_{\mu\nu} + D(\phi,\partial \phi) \partial_\mu\phi \partial_\nu \phi$. By solving the background evolution equation, we found that such theory cannot provide the self-accelerating solution.

Speaker: Mr Saksith Jaksri (Naresuan University)

conference_poster_3ed.pdf

364 The Effect of Epoxy Molding Compound Floor Life to Reliability Performance and mold ability for QFN Package

This research studied about an epoxy molding compound (EMC) floor life to reliability performance of integrated circuit (IC) package. Molding is the process for protecting the die of IC package form mechanical and chemical reaction from external environment by shaping EMC. From normal manufacturing process, the EMC is stored in the frozen at 5 C and left at around room temperature for aging time or floor life before molding process. The EMC floor life effect to its properties and reliability performance of IC package. Therefore, this work interested in varied the floor life of EMC before molding process to analyze properties of EMC such as spiral flow length, gelation time, and viscosity. In experiment, the floor life of EMC were varied to check the effect of its property to reliability performance. The EMC floor life were varied from 0 hours to 60 hours with a step of 12 hours and observed wire sweep, incomplete EMC, and delamination inside the packages for 3x3, 5x5 and 8x8 mm2 of QFN packages. The evaluation showed about clearly effect of EMC floor life to IC packaging reliability. EMC floor life is not any concern for EMC property, moldabilty, and reliability from 0 hours to 48 hours for molding process of 3x3,5x5 and 8x8 mm2 QFN packaging manufacturing.

Keywords: Integrated circuit (IC) packaging, epoxy molding compound (EMC), molding compound floor life, gelation time

Speaker: Mr Udom Peanpu-Nga (Student)

365 The investigation physical and electric properties of Mg1-xMnxFe2O4 ceramics

We have reported physical and electric properties of Mg1-xMnxFe2O4 (MMF) (x = 0.5 - 0.7) ceramics were prepared using co–precipitation method. The effects of Mn content on the phase formation, morphology, density and electrical properties were investigated. The XRD analysis of the as synthesized powder confirms the formation of the single phase MgMnFe2O4 spinel structure. The microstructure exhibited a rectangular square grain in all samples. The average grain size and the density of the ceramics increased from 2.8 to 8.7 µm and 3.35 – 3.59 g/cm3 by increasing Mn content. The dielectric constant and dielectric loss decreases with increasing frequency but these parameters increase with increasing temperature.

Speaker: Nititorn Kenyota

Investigation Physical and Electrical Properties of Mn1-xMgx Fe2O4 Ceramics

Research-paper-MMF-1.pdf

366 The measurement of cosmic-ray muon

Cosmic-ray muons are produced in the atmosphere as results of the collision of incoming high-energy particles, i.e. cosmic rays, from outer space with atmospheric particles. In this work, a simple detector has been built to measure the speed of cosmic-ray muons. The detector is composed of two scintillation bars of a rectangular cross-sectional area of 4×6 cm$^2$ and a length of 127.5 cm, with photomultiplier tubes (PMTs) attached at both ends of each scintillation bar. The two bars are vertically aligned in the parallel positions with a distance of 76 cm apart. When a cosmic-ray muon passes through the scintillator, it creates scintillation light. The light will be collected by the PMTs and converted to electrical signals which will be measured using a 4-channel oscilloscope. The time delay between the observed signals obtained from the 4 PMTs are recorded and used to calculate the speed of cosmic-ray muon.

Speaker: Mr Jittrathep Sukultanasorn (Department of Physics, Faculty of Science, Chulalongkorn University)

367 The production ${K^ + }$ meson in Al+Al collisions at beam energy 1.9A GeV.

The kaon production in heavy ion collisions at intermediate energies provides a sensitive probe to study the in-medium properties and nuclear equation of state. Kaon properties in dense hadronic matter are important for understanding of nuclear matter at high densities. We investigated the in-medium kaon potential by rapidity density distribution and transverse mass spectra for ${K^ + }$mesons in heavy ion collisions. We used Quantum Molecular Dynamics Model (QMD model) based on covariant kaon dynamics to simulate ${}_{13}^{27}Al + {}_{13}^{27}Al$ collisions at beam energy 1.9 A GeV. Calculated results with a repulsive in-medium ${K^ + }N$ potential can reasonably describe the features of FOPI experiment data. They also shown that the transverse mass spectrum of ${K^ + }$ mesons is a sensitive observable to probe the kaon in-medium potential in dense nuclear matter.

Speaker: Ms Kristiya Tomuang (Department of Physics Faculty of science Naresuan University)

368 The Pulsational Analysis of the oEA component of RX Hydrae

RX Hydrae is a bright Algol-type eclipsing binary system with orbital period is 2.2825 days. This system was classified as the member group of oEA stars in 2002. The short-periodic pulsations of a primary component were detected by Kim et.at (2002) who classified the system as a new member of oEA group of pulsators. The new CCD photometric and spectroscopic observations of RXHya were obtained in 2014-2015 in order to study the pulsation spectrum. The B-filter CCD photometry was acquired on Thai Southern Hemisphere Telescope (TST, PROMPT-8) at Cerro Tololo Inter-American Observatory (CTIO) in Chile. The spectroscopic observations were acquired with fiber-fed medium resolution echelle-spectrograph of the 2.4-meter telescope of Thai National Observatory (TNO). Binary light curve and the radial velocity curve of the primary oEA component of RX Hya were subtracted using polynomials fitting to get the residual observational data. The period search in the residual data was performed using the Period04 software (Lenz & Breger, 2005). From the analysis of photometric residuals we found the two pulsation frequencies at 19.344 $\pm$ 0.004 c/d ($\bigtriangleup$B=0.003mag) and 31.351 $\pm$ 0.005 c/d ($\bigtriangleup$B=0.0026 mag). We confirmed existence of pulsations at these frequencies 19.343 $\pm$ 0.002 c/d ($\bigtriangleup$RV=0.36 km/s) and 31.254 $\pm$ 0.002 c/d ($\bigtriangleup$RV=0.37 km/s) in the residual radial velocities. Thus, we detected a new mode and independently confirm existence of at least two oscillation modes in RX Hya.

Speaker: Ms Napaporn A-thano (National Astronomical Research Institute of Thailand)

369 The Relationships Between Wind Speed and Temperature Time Series in Bangkok, Thailand.

In this research we investigate the relationships between wind speed and temperature time series data in Bangkok, Thailand, from the time interval of January 2009 to December 2011 using wavelet transform (WT), cross wavelet transform (XWT) and wavelet coherence (WTC). The results from all three wavelet analysis show the strong periodicity around period 1 day (hourly data) and period band 256-450 days (daily data) variations that are exhibited in both wind speed and temperature data across the entire power spectrum from 2009 to 2011. These two oscillations are connected with the natural day time effects and the annual natural season cycle. Although the daily periodic for the temperature is appeared nearly uniform all year but it is not the case for wind speed. In 2009 this wind speed oscillations appear only from mid February to mid April in summer and from the fourth week of May to the third week of August in rainy season. XWT also detects strong high common power between the wind speed and temperature at a period band of 14-25 days in summer 2009, a period band of 4-8 days in summer 2009, July 2009, summer 2010 and summer 2011. WTC shows the coherence period band around 10-30 days appeared in summer and rainy season and 32-50 days in summer 2009 and rainy season in 2010. From these three wavelet analysis, the wind speed and temperature time series data show the strong correlation especially at 1 day and 256-450 days period band and also at several different scales. This studied will be helpful in predicting the wind speed and temperature for the future used.

Speaker: Dr Nipon Thangprasert (Physics)

Relationships3_2.pdf

370 The solar energetic particle propagation of solar flare events on the 24th solar cycle

Now the Sun is in the 24$^{th}$ solar cycle. The peak of solar cycle corresponding to the number of the Sun activities, which one of them is solar flare. The solar flare is the violent explosion on the surface of the Sun and releases the high energy ion from the Sun to the interplanetary medium. Solar energetic particles or solar cosmic ray have important effect on the Earth, such as disrupt radio communication. We analyze the particle transport of the solar flare events on August 9, 2011, January 27, 2012, and November 3, 2013 in 24th solar cycle. The particle data for each solar flare was obtained from SIS instrument on ACE spacecraft. We simulate the particle transport with the equation of Ruffolo 1995, 1998. We solve the transport equation with the numerical technique of finite different. We find the injection duration from the Sun to the Earth by the compared fitting method of piecewise linear function between the simulation results and particle data from spacecraft. The position of these solar flare events are on the west side of the Sun, which are N18W68, N33W85, and S12W16. The results show the mean free path was increased as well as the injection time was decreased while the energy level was increased. The resultant variation of the highest energy and lowest energy was small because the effect of space environments and the number of data was small. The high mean free path of the high energy particles showed the transport capability of particles along to the variable magnetic field line. The violent explosion of these solar flares didn’t affect on the Earth magnetic field with Kp-index less than 5.

Speaker: Ms Papitchaya Paluk (Department of Physics, Faculty of Science, Naresuan University, Phitsanulok 65000, Thailand)

371 The study of physical properties of low density sub-Saturn mass exoplanet HAT-P47b

Nowadays, the studies of exoplanets are extensive and various. The different techniques are used to analyze the masses, radii and other specific data about exoplanets. HAT-P-47b transiting exoplanet candidate is a recent discovered low density sub-Saturn mass exoplanet. The planet is one of the lowest mass planets with the radius larger than Jupiter radius, which is a suitable candidate for exoplanet atmosphere. We observed HAT-P-47 host star 2 nights with 2.4 m Thai National telescope and 0.7 m robotic telescope at Lijiang observatory, China, between 2016 and 2017. We can confirm the transits of the planet. The HAT-P-47b planetary parameters are revised using the Transit Analysis Package.

Keywords : exoplanets, transit timing variation, the heaviest mass scope of the other planet, star HAT-47, planet HAT-P47b, star HAT-47’s light decreasing

Speakers: Mr Jathurawit Mateewattanakul (ChiangMai University Demonstration School ), Ms Supichaya Padjaroen (Chiang Mai University Demonstration School)

372 The thermal insulators fabricated from leaves green tea with water hyacinths

Abstracts
The purpose was study about the properties of the insulation fibers panels from waste of tea leaves and water hyacinth. it mixed together in 5 ratio 100:0 , 80:20 , 50:50 , 20:80 , 0:100 with compress insulation by machine by 120 kg/square centimeter in 10 minutes product is flat size 400x 400 mm. and thickness is 10 mm. will produce insulation at a density of two conditions is 400 and 800 kg per cubic meter of 5 discs in one state overall summary sheet insulation to produce a total of 10 sheets. the possibility to study the thermal properties compared to standard commercial discs. Physical Properties And mechanical tests according to JIS A 5905-1994.
The results showed Insulation panels made from waste tea leaves with water hyacinth fibers are mixed at 50% is a good type of insulation. This is based on the heat between 0.058 to 0.089 watts per meter degree Celsius. The physical properties testing And mechanical properties The insulation panels from waste tea leaves, water hyacinth fibers with a density of 800Kg / m3. That is the best because the disc is a high density. A standard feature of the plate better JIS A 5905-1994. Sheet with low density.

Speaker: Mr Nikorn Suksawad

373 Theoretical study of the hydration structure and interaction energy of Sorbitan monostearate (Span60) by using hybrid quantum mechanical/molecular mechanical (QM/MM) method

The hybrid quantum mechanical/molecular mechanical (QM/MM) method has been used to investigate on mono-hydration and poly-hydration phenomena of the polar head group of Span 60 molecule in both gas and aqueous phases. Our calculations were performed by using Gaussian 09 program. The result indicates that Span 60 interacting with one water molecule shows the mono-hydration effect of the head group. When adding more water molecules around the Span 60 head group, the poly-hydration phenomena is clearly observed. Thus, it suggests that the QM/MM approach in this work is the precise and efficient method to investigate on the conformation and the hydration structure as well as the interaction energy of the Span 60 polar head group.

Keywords: Span 60, QM/MM method, hydration structure and interaction energy

Speakers: Mr Nikorn Shinsuphan (Department of Physics, Faculty of Science, Khon Kean University, 123 Mittraparp Road, Khon Kaen, 40002 ), Dr Sriprajak Krongsuk (Department of Physics, Faculty of Science, Khon Kean University, 123 Mittraparp Road, Khon Kaen, 40002, Integrated Nanotechnology Research Center, Faculty of Science, Khon Kaen University, Khon Kaen, 40002 ), Dr Jeffrey R. Johns (Melatonin Research Group, Faculty of Pharmaceutical Science, Khon Kaen University, Khon Kaen 40002, Thailand)

374 Theoretical Study on Structural and Electronic Properties of Polypyrrole: Ammonia Gas Sensor

Polypyrrole (PPy) have been considered as one of the most promising conducting polymers for gas sensor application due to it can operate efficiently at room temperature, light weight, thermal stability and high sensibility. In this research, we have been reported the geometric and electronic structure of PPy based on B3LYP/3-21G$^*$, B3LYP/6-31G$^*$ and SCC-DFTB methods. The effects of polymer chain length of PPy on structural and electronic properties including bond length, bond angle, torsion angle, the highest occupied orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) and energy gap have been studied from the optimized PPy oligomers (n=1-10). The results show that the bond length, bond angle and torsion angle from SCC-DFTB method are C-N = 1.38 Å, N-H = 1.04 Å, C-C = 1.45 Å, N-C-C = 122 $^o$, C-C-C = 131$^o$, N-C-C-C = 179$^o$ and C=C-C=C = 179$^o$, respectively. The HOMO and LUMO are ranging from -5.49 to -4.23 eV and -0.078 to -1.92 eV, respectively. The energy gap decreased with increasing polymer chain length from 5.41 to 2.31 eV. Furthermore, the results based on B3LYP/3-21G$^*$, B3LYP/6-31G$^*$ and effects of PPy ammonia gas sensor have been investigated and discussed in more detail.

Speaker: Ampaiwan Marutaphan (Rajamangala University of Technology Suvarnabhumi)

375 Thermal Characterization of Clay Roof Tile Using Photothermal Deflection Technique

In this research, a nondestructive, simple and rapid method, photothermal deflection technique or the so-called “mirage effect”, is setup. A flat and smooth sample is heated by a modulated 532nm 14mW pump beam on the surface. The heat flow induced by the surface layer is detected by the deflected 632nm 0.14mW probe beam. The frequency-dependent signal in the range of 1 - 800 Hz is measured by lock-in amplifier in term of amplitude and phase. The clay roof tile with and without the waterproof glaze layer on top is measured. Thermal diffusivity of the clay roof tile and the waterproof glaze layer is determined by the theoretical model.

Speaker: Tanawut Rittidach

376 Thermal Efficiency of Natural Convection Solar Dryer

This research is to study thermal efficiency of natural convection. Working principle of natural convection solar dryer is, once air in solar dryer is heated by solar energy, the air relative humidity will drop and floating up through the drying. This air will take moisture out of the product and flow out to ambient air. It was found from the experiment that, in the duration of 8.00 am – 4.00 pm on a clear sky day, an all-day average ambient air and inside the chamber temperature was 37.01 $^o$C and 62.24 $^o$C respectively. At solar radiation intensity of 763.82 W/m$^2$, mass flow rate of air was 0.029 kg/s and thermal efficiency of the solar dryer was 2.54%.

Speaker: Ms Pitchpilai Khoonphunnarai (Department of Physics and General Science, Faculty of Science and Technology, Songkhla Rajabhat University)

377 Thermal Properties of Green Briquettes Fuel from Corn Cobs Residue Materials Mixed Macadamia shell Charcoal Powder

The objective of this research was to produce green fuel briquettes from corncobs by adding macadamia shell charcoal powder. The study was sectioned into 3 parts: 1) Quality improvement of green fuel briquettes by adding macadamia; 2) Fuel property analysis based on ASTM standards and efficiency on heat capacity; and 3) Economics appropriateness in producing green fuel briquettes. This research produced green fuel briquettes using the ratio of corncobs weight and macadamia shell charcoal powder at 100:0 90:10 80:20 70:30 60:40 and 50:50 and pressing in cold briquettes machine. Fuel property analysis showed that green fuel briquettes at the ratio 50:50 produced maximum heating values at 21.06 Megajoule per kilogram and briquettes density at 725.18 kilogram per cubic meter but percent of moisture content, volatile matter, ash, and fixed carbon were 10.09, 85.83, 2.17 and 1.91 respectively. Heat capacity efficiency of green fuel briquettes was in average at 20.22%. Economics appropriateness at the ratio of corncobs weight and macadamia shell charcoal powder at 50:50 which accounted for the cost per kilogram at 5.75 Baht. The net present value was at 1,791.25 Baht. Internal rate of return was at 8.62 and duration for payback period of investment was at 1.6 years which was suitable for investment.

Speaker: Suminya Teeta

378 TRIBOLOGICAL CHARACTERIZATION OF ELECTRONIC GRADE LUBRICANTS USING BALL-ON-DISK TRIBOMETER

Abstract
In microelectronic industry, the lubricants are used in the wafer-to-chip grinding and lapping processes before device assembly step. The based lubricant and additives play important roles in the product quality and reliability for those nano-scale fabrications. In this study, the tribological behaviors of AlTiC surface that sliding against AISI304 balls were studied in electronic-grade ethylene glycol (EG) based and mineral oil lubricants by using ball-on-disk Tribometer. The friction force and coefficient of friction of different lubricants are measured and calculated. The results showed the COF depends on many factors such as types of lubricant, load and speed. The different additives in lubricant also play an important role to the friction force. It showed that an increasing sliding speed can also decrease COF. The different in contact mechanic results in different material removal rate.

Speaker: Ms Sawanee ๋Jitphayomkun

379 Warpage of QFN Package in Post Mold Cure Process of integrated circuit packaging

This research studied about warpage of QFN package in post mold cure process of integrated circuit (IC) packages using pre-plated (PPF) leadframe. For IC package, epoxy molding compound (EMC) are molded by cross linking of compound stiffness but incomplete crosslinked network and leading the fully cured thermoset by post mold cure (PMC) process. The cure temperature of PMC can change microstructure of EMC in term of stress inside the package and effect to warpage of the package due to coefficient of thermal expansion (CTE) between EMC and leadframe. In experiment, cure temperatures were varied to check the effect of internal stress due to different cure temperature after completed post mold cure for TDFN-8L. The cure temperature were varied with 180°C, 170 °C, 160 °C, and 150°C with cure time 4 and 6 hours, respectively. For analysis, the TDFN-8L packages were analyzed the warpage by thickness gauge and scanning acoustic microscope (SAM) after take the test samples out from the oven cure. The results confirmed that effect of different CTE between EMC and leadframe due to different cure temperature resulting to warpage of the TDFN-8L packages.

Speaker: ์NATTHA SRIWITHOON

380 XMM-Newton observations of the ultraluminous X-ray source NGC 1313 X-1: a super-Eddington accreting black hole

**

Abstract

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Ultraluminous X-ray sources (ULXs) are non-nuclear, extra-galactic X-ray point sources with X-ray luminosity ($L_{\rm X}$) in excess of the Eddington limit for a 10 M$_{\odot}$ black hole ($L_{\rm X}$ $>$ $10^{39}$ erg s$^{-1}$). It is thought that the majority of ULXs are accreting black holes. However, due to their extreme brightness, the mass of black holes powering ULXs is still the topic of active debate. In this work, we study the high quality X-ray spectra of the nearby ULX NGC 1313 X-1 using the observational data from XMM-Newton observatory. A range of physical models is used to model the ULX spectra and to interpret the results physically. The modeling results indicate that the spectra consist of two components. We argue that the spectra could be explained well using a super-Eddington accretion model in which a stellar-remnant black hole is accreting material above the Eddington rate. Indeed, the high energy component of the spectra could be explained well using the super-Eddington slim accretion disc model. Moreover, assuming that the low energy spectral component is the X-ray emission from the putative outflowing wind, the wind radius could be calculated. Alternatively, using the model of accretion disc around Kerr black hole to fit with the high energy component, the mass of black hole powering the ULX could be constrained to $\sim$10 M$_{\odot}$, supporting that the ULX is powering by the stellar-remnant black hole. Finally, we demonstrate that the ULX spectral variability could be explained successfully in the context of the super-Eddington accretion model.

Speakers: Mr Surasak Loekkesee (Srinakharinwirot University), Ms Kewalin Thongpoyai (Srinakharinwirot University)

19:00 Conference Dinner & Closing Ceremony

Friday 26 May

09:00 Conference Excursion

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