Jiangmen Underground Neutrino Observatory (JUNO) is now under construction at Jiangmen, Guangdong, China for determination of neutrino mass ordering with 3% energy resolution at 1 MeV, a precise measurement of neutrino oscillation parameters, and other neutrino physics. The central detector is made up from a 35.4 meters diameter acrylic sphere which contains 20 kton of liquid scintillator...
Fluorescence spectroscopy plays an important role in biosensing and chemical sensing applications because of various advantages, for instance, high sensitivity and low electrical interferences. Even though the technique often provides very low limits of detection, the high cost and bulkiness of commercial fluorescence spectrophotometers are key limitations that keep most fluorescence based...
This work presented a simple method to improve electric-energy generation of solar photovoltaic (PV) panel using an integrated-mirror reflector. The reflector was integrated with PV panel and adjusted incline angle to optimize better sunlight collection. The PV performance was evaluated from current and voltage, which were recorded by Arduino data logger. The integrated-reflector PV panel at...
It has been more than 200 years since Thomas Young discovered light interference. After all this time, physicists still have a tough time producing phase differences in their interferometer. The root of this problem is the moving of an arm of the interferometer to create phase differences. In nature, the coherence length of light is extremely small so when they move the arm it has already out...
Geodesy is an important tool for national development. Data obtained from geodetic techniques so-called geodata can be used for various applications, and also become one of the national infrastructures achieving the goal of becoming Innovative Thailand. Currently, the main geodetic facility of the country is the network of GNSS Continuous Operating Reference Stations or CORS. However, data...
Studying science through hands-on activities within the context of teaching and learning using local environments and resources has been recognized as one of the fundamental prerequisites of school curriculum in many developing countries, including Thailand. Accordingly, we are interested in implementing such concept in designing science teaching and learning suitable for students in the...
One of the most interesting consequences of string/M-theory, the most promising candidate for a theory of quantum gravity, is the AdS/CFT correspondence or AdS/CFT holography. This is a duality between string/M-theory on $AdS_{d+1}\times M$ backgrounds and d-dimensional conformal field theories on the boundary of $AdS_{d+1}$. Being a strong-weak duality, the AdS/CFT correspondence and its...
Abstract. The Thai population has the seafood as an important component in their diet because seafood are a source of protein that is easily available. This paper aimed to determine the 210Po concentrations in 5 species of shellfish, i.e., green mussel (Perna viridis), oyster (Saccostrea cucullata), enamel venus clam (Meretrix meretrix), radiated scallop (Amuseum pleuronectes) and cockle...
This paper presents an application of reflective holographic gratings for the measurement of cylindrical curvature. The surface of fabricated holographic grating was coated with gold by the sputtering method, where it becomes a reflective holographic grating. The grating was attached to the surface of various radius cylindrical objects. The diffraction pattern produced by the bent grating with...
We investigate an alternative way to detect the gravitational wave using the concept of Aharonov-Bohm experiment in curved space-time. Our system consists of an electron beam which is split into two beams passing opposite sides of the solenoid and producing interference patterns. The change in interference patterns can be observed if the system is perturbed by the gravitational wave, and can...
In this work, we want to find out the bound states and energies of the Newton’s equivalent quantum mechanics (NEQM) which construct from 1-parameter family ($\beta$) of Newton's equivalent Hamiltonian (NEH) in asymmetrical finite square well system. Classically, NEH is Hamiltonian which is equivalently to standard one yielding the same Newton's equation. In quantum system, by ordering problem...
The first tokamak in Thailand is being setup by Thailand Institute of Nuclear Technology (TINT) at the Ongkharak site, Nakorn Nayok. In the initial phase of th tokamak, plasma current of 50 kA, with density of 1018 m-3 under the magnetic field of 1.5 Tesla is expected. Plasma discharge of typically 100 ms is foreseen for each shot and a few hundred shots daily. Machine preparation and...
Optical diffraction of opal, a colloidal photonic crystal, can be predicted by Bragg-Snell diffraction and photonic band structure. Theoretical prediction and optical measurement are frequently slightly different due to distance variation of particle packing. In this research, opal of 310 nm polystyrene beads was fabricated by self-assembly process and optically investigated in transmission...
For chicken industry, hens are raised in large farmhouses which usually difficult to control for complete sanitation. It is very likely that contamination of chicken meat and eggs could occur. This research project aims to improve farmhouse floor disinfection and eggshell sanitization using UV and IR irradiation in aspects of time-saving, accuracy and environmental friendly.
Rice husks are...
Helmholtz resonance is a resonance phenomenon in a container such as an empty bottle with an open hole. A sound is produced by blowing across the top of an empty bottle and the air near the open hole and in the bottle is vibrated. The resonance frequency, $f$, is determined by the shape and dimension of cavity. The volume of the empty bottle is denoted as $V$, the cross-sectional area of the...
Study on assessment of contamination of natural and artificial radionuclides in agricultural products samples are very important to all human being as a consumer. In the present study, we have measured and evaluated the specific activities of natural (40K, 226Ra and 232Th) and anthropogenic (137Cs) radionuclide in rice samples. The 30 rice samples were collected from from general and...
The Central Molecular Zone (CMZ) in the Galactic Center region shows outstanding non-circular motion unlike the Galactic disk. Although several models describing this non-circular motion are proposed, and uniform kinematic model of the CMZ orbit is not appeared.
Three dimensional velocity velocity information including proper motions will be critical to constrain the orbital models of the CMZ...
Forecasting the astronomical seeing above an observatory can assist astronomers plan their observations. In this study, the astronomical seeing above the Thai National Observatory (TNO) in Doi Inthanon, Chiang Mai, Thailand was simulated using the Weather Research Forecasting (WRF) model. The model outputs were then compared to seeing observations using Polaris and the Differential Image...
Coherent perfect absorption (CPA) is a multichannel waveform shaping protocol, which leads to a complete extinction of a monochromatic radiation when it enters a weakly lossy cavity. Its physical origin is traced to wave interference effects that entraps the incident radiation inside the lossy cavity. The CPA is an intrinsic resonance phenomenon. Its validity has been tested in a variety of...
The accurate and efficient estimator of the star formation rate (SFR) is a powerful tool to study galaxy formation and evolution. However, such an estimator has proven challenging to derive for high-redshift star-forming galaxies because of the observing limitations: the interstellar dust attenuation in dusty star-forming galaxies at ultraviolet and optical makes it hard to obtain accurate...
This research aimed to present the human arm movement as badminton motion by using a triple physical pendulum model for propose of the up-down swing of human arms. Human arms have three segments, contacted together via joints; such as the three links of the rod masses of the triple physical pendulum swing when playing badminton that can use the Euler-Lagrange equation and tracker physics to...
An interference experiment of twin photons using Mach - Zehnder interferometer has been performed. Twin photons called signal and idler are the pairs of temporally correlated photons with identical properties. The photons are produced with a type-I spontaneous parametric down-conversion process in a BBO nonlinear crystal. The single photons (signal photons) are sent along one path of the...
Yellow sapphire is a gemstone variety of corundum (Al2O3). The yellow color is commonly caused by Fe3+ impurity substituting for Al3+ in the Al2O3 structure. The depth of yellow color is linked to Fe3+ concentration. The higher content of Fe3+ produces a deeper yellow color. The quantitative relationship between color and the chemistry of natural corundum has been comprehensively studied [1]....
The inflationary scenario is formulated so far by the introduction of (elementary) scalar fields (called inflaton) with a nearly flat potential. However, we can imagine the possibility that the inflaton need not be an elementary degree of freedom. In this talk, we revisit the cosmological scenario in which the inflaton is a composite field emerging in the scalar channel of the effective...
Air pollution is a major concern for the population in Chiang Mai the same as most people in the other large cities in the world. Hazy skies and pollution alert have become normal during late winter and entire summer almost every year. Prolonged expose to PM2.5 can cause acute and chronic effects to the respiratory and cardiovascular systems. This research aims to study the correlations...
To understand experimentally obtained net-proton number cumulants in the search for the QCD critical point, we study a dynamical model based on an effective quark-meson Lagrangian with chiral symmetry. We investigate the evolution of the expanding medium created in a heavy-ion collision using a spatially homogeneous fluid and a time-dependent order parameter, the sigma field evolved by a...
Light in nature is known to behave following the law of reflection. Light ray hits surface with a different orientation and reflects in accordance with the rules of physics. For rendering realistic image, it is difficult to calculate the light reflection of complex foliage, such as trees, the reflection of this natural complexity needs to be adapted to particular rendering situations. In this...
Abstract. This research was to analyze the density and rock types of fossils found in soil wells of La-ngu district at Satun Geopark. To compare the density and rock types found in other fossils of Thailand. Rock samples were collected in class five layers, each layer separated about 1-1.5 meters, the characteristics of each rock floors posing clear distinction has collected rocks as three...
The instrumentation used to measure the parameters or diagnostics of the beam is an essential part of any particle accelerator. Beam diagnostics play a key role in the operation of the accelerator, and are necessary to determine the performance of the source. The aim of this article is to present a design for one type of beam diagnostics tool, the Faraday cup, which can be used to measure the...
There are numerous moons orbiting planets in our solar system. This implies the existence of exomoons around exoplanets. The result in previous study shows unique features in Transit Timing Variations (TTV), Transit Duration Variations (TDV) and transit depth signals around the primary and secondary transits of exoplanet transiting models due to moon phase evolution. The aim of this work is...
The non-linearity of probes is an important component in gauge block calibration by mechanical comparative method of two gauges blocks at the same nominal length. However, an advance method for gauge block calibration is a mechanical direct measurement method of two gauges block showing the greatest difference in nominal length 25 mm. This method used special probe base on the interferential...
Small-diameter artificial blood vessel is synthesized with a diameter less than or equal to 6 millimeters. This technique has been utilized in coronary artery bypass grafting, in order to treat the coronary artery disease. Currently, the problem from coronary artery disease is still found in common, in addition to aortic aneurysm caused by incompatibility of mechanical properties between...
Abstract
The research aim was to develop creativity of grade 5 students through STEM education in electricity. There were 15 students of Grade 5 in Khon Kaen Province of the second Semester in 2020 who participated in this study. The action research was implemented to this study with tree loops to improve creativity of students. The physics contents of Grade 5 on electricity...
Photoplethysmography (PPG) is one of the optical signals commonly used in clinical research for measuring virtual signs. In some previous studies, PPG was often used as an indicator for detecting blood volume changes in the micro-vascular. The advantages of PPG signal the mentioned in studies are; non-invasive, lower operation cost, and the simplicity of the procedure. Although some the...
Optical coherence tomography (OCT) is an optical imaging technology that uses low temporal coherence of broadband near infrared light to image depth cross-section structure of biological sample at micrometers resolution. OCT uses the low coherence of light as a selection window to non-invasively and precisely gate light reflection and scattering at specific depth location underneath the...
Understanding in the astronomy about the star and constellation on a real sky are misinterpretation for student. In this research, students’ understanding about the star and constellation were developed by using active learning method.
Activities use in active learning was pointing the stars and constellation on a real sky. The participants were 103 pre-service teachers in general science...
The Moon phase is an astronomical phenomenon showing the Moon shape in a sunlit portion as viewed from the Earth and can be observed worldwide. This relates to the position of the Moon in its orbit around the Earth. Thanks to the evolution of human intelligence and technology, it is nowadays easy for astronomers to calculate and predict the lunar phases: full moon, waxing or waning gibbous,...
The Plasmas Material Interaction (PMI) Linear device, the only linear device in Thailand, is a plasma source that generating plasma by using helicon wave and maintaining plasma beam by using a strong magnetic field to reduce particle loss. The main purpose of PMI linear device is to serve as a material testing device. In order to serve its purpose, its plasma parameters and characteristic must...
We investigate changes in the correlation function of time-dependent wave function due to a dimensionality reduction in geometrical construction of quantum channels. The correlation functions give signatures that point to dominant eigen energies in all dimensions when the channel evolves from a 2D finite well to approach a 1D long one. On the other hand, when we introduce an obstruction in the...
In this research, the Kalman filter method was applied for correcting precipitations simulated by a high resolution regional climate model, NHRCM during the period of 1980-1999. The improved average monthly precipitations were close to the stational observations. To reduce systematic error, the Kalman filter method was also applied to simulated monthly precipitations during the future period...
The AdS/CFT correspondence is a relationship between a quantum gravity theory on d+1 dimensional Anti-de-Sitter (AdS) space-time (or bulk) and conformal field theory (CFT) which is the quantum field theory on d-dimensional space-time (or boundary). It was proposed by Juan Maldacena in 1997. This duality is very useful because it enables us to convert the problem in field theory to string...
Spiral waves has been observed in a thin layer of excitable media. Especially, electrical spiral waves in cardiac tissues connect to cardiac tachycardia and life-threatening fibrillations. The Belousov-Zhabotinsky (BZ) reaction is the most widely used system to study the dynamics of spiral waves in experiments. When the light sensitive $Ru(bpy)_3^{2+}$ is used as the catalyst, the BZ reaction...
One of the factors of respiratory disease is a smoke particle from air pollution, many researchers have tried to detect and catch it. This aim of experiment was to investigate the effect of electric potential difference of a Dielectric Barrier Discharge (DBD) system used for trapping joss stick smoke particle at atmospheric pressure. Dielectric Barrier Discharge (DBD) consists of inner...
Nanocrystalline powders of Fe-doped SnO2 (x = 0.00, 0.01, 0.03, 0.05) were synthesized by hydrothermal method. The powders were calcined in argon atmosphere at 600 oC for 2 h, phase transition from diamagnetic and weak ferromagnetic behavior to a ferromagnetic state. No trace and other magnetic impurity phase was detected in the samples with Fe content up to 3%. The magnetic properties of the...
Thai Hom Mali Brown Rice (Oryza cultiva L.) is rich complex and beneficial bioactive compounds. Several bioactive compounds are known to accumulate in brown rice during germination process. This study was to investigate the effect of electron beam irradiation for activation bioactive compounds of Germinated Brown Thai Hom Mali Rice, local rice cultivar from Sakon Nakhon province, Thailand. ...
In atom-based electric field measurement, an atomic vapor in a glass cell is used for detecting electric field signals. The vapor pressure of the atoms inside the cell has to be high enough so that the signal can be recovered from the noisy background. One technique used for increasing the vapor pressure in the glass cell is light-induced atomic desorption (LIAD). By emitting light with higher...
In this research work, nanostructured chromium zirconium nitride (CrZrN) thin film have been deposited on Si(100) substrates by reactive DC magnetron co-sputtering method without in situ substrate heating and post-deposition annealing. The effects of Zr content, by varied the sputtering currents applied to the Zr target (Izr) in the range of 300 to 900 mA, whereas the current of Cr target was...
High confinement mode or H-mode for fusion plasma in tokamak is an important phenomenon, and it is necessary because many basis quantities are raised up, such as plasma density, pressure, and temperature. These are useful to fusion reaction because both the chance of reaction and temperature are increased, which allows higher fusion power. But plasmas with high pressure and temperature are...
The constantly increasing demand for electric energy in the present world results in the need for energy storage such as batteries, capacitors and supercapacitors. Supercapacitors are durable and can charge electricity faster and keep electric charge longer. In this study, electrodes for supercapacitors were made from aluminum foils coated with carbon nanotube film, and separated by...
Electronic and magnetic calculations of zinc-blend (β) structure of MnS based on density functional theory were investigated using ultra soft pseudopotential. The spin orientation on Mn atoms was used to identify MnS magnetic phase. The DFT+U method was employed to predict underestimated band gap which obtained from standard DFT. In this calculation, Hubbard (U) energies are varied from 0 to...
Thioflavin T (ThT), a cationic fluorescent dye, and the bimolecular G-quadruplex (biGQ) DNA (two guanine-rich single-stranded DNAs, 5’-TGAGGGAGGGGT-3’) have been used to develop an optical sensor for potassium ion (K$^{+}$) detection based on the fluorescence characteristic of ThT in different environments. Fluorescence intensity of free ThT in non-viscous media is extremely low due to the...
The research as study to elemental quantity in particulate matter (PM10) at community where near factory as source found analysis of PM10. Which PM10 smaller sizes than of 10 µm from soil, rock, ash from leaf and ash from bagasse, respectively. PM10 were collected from around area and were pumped into filter paper by personal pump machines. PM10 were weighted by four point digital balance as...
The ELM phenomenon in fusion plasma is studied based on bifurcation concept. Three transport equations including thermal, particle and momentum in toroidal direction are solved simultaneously, resulting in the prediction of plasma pressure, density, and toroidal momentum profiles as functions of time and radius. The transports include both neoclassical and anomalous effects with the velocity...
Energy conversion of electrostrictive poly (vinylidene fluoride-co-hexafluoropropylene), P(VDF-HFP) polymer filled with graphene nanosheet (GNPs) was investigated. Those composites were fabricated by solution casting method. In fact, dielectric constant is one of key performance of the energy conversion based on the electrostrictive materials. Thus, the LCR meter was used to determine the...
The valence bond solid (VBS) state is the ground state of the Affleck-Kennedy-Lieb-Tasaki (AKLT) spin model, which has recently been proved to be the universal resource for measurement-based quantum computation, e.g., the spin-2 AKLT state on the square lattice. The VBS state is defined on various two-dimensional (2D) lattice structures with open and close (periodic) boundary conditions...
This research work investigated the properties of concrete block made from Portland cement and aggregate replacement materials. Portland cement (PC) was replaced by fly ash (FA) at 10%, 20%, 30% and sand was replaced by bottom ash (BA) at 10% by weight. Water was used at 7% by weight of total solid mass. Binder : Sand : Stone dust ratio of 1 : 5 : 6, 1 : 4 : 5 and 1 : 3.5 : 4.5 were...
A liquid plasma facing surface, e.g. made of lithium, has been investigated its benefit to fusion plasma operations in past several years. Notably, it has been observed that such a surface placed too deep from a tokamak wall leads to heavy impurity release. Subsequently, the confined plasma cannot tolerate the excessive impurity inventory, and this results in disruption achieving by radiation...
A passive integrating discriminative radon-thoron monitor (Raduet) and radon-thoron progeny monitor (RnP-TnP monitor) with a solid state nuclear track detector (SSNTD) were used for estimating indoor radon, thoron and their progeny concentrations in residential areas around the old mines of the southern Thailand. The exposure to high background radiation level from Uranium-238 and Thorium-232...
One of alternative energy sources which has globally pay more attention is wind power. In this research, the Weibull wind speed distribution was applied to evaluate wind energy potential during the period of 2081-2090. The projected wind datasets were simulated by the Non-hydrostatic Regional Climate Model (NHRCM) forced by the 20 km resolution MRI Atmospheric General Circulation Model...
Exoplanets are planets that orbit around other stars outside the solar system. One of methods that can be used to locate them is transit method. In transit method, the variation of the flux from the host star is observed when the planet passes in front of it. There are periodic dips with a period equals to the orbital period in its light curve where the time between ingress and egress is...
Students consider physics to be one of the most prevalent and troublesome topics since they find physics to be a challenging course in high school and become more deceptive when they have it as an undergraduate course. The Rizal Technological University (RTU) in the Philippines offers undergraduate and graduate academic programs in astronomy. The university utilizes physics diagnostic tests to...
More than 100 years ago, cosmic rays were discovered. Through the studies of cosmic rays and related phenomena, we learned that there are various high energy phenomena in the Universe that cannot be studied by optical telescopes. For example, the mechanism of Supernova explosion can be understood only by the observations of neutrinos and gravitational waves. In this talk, I will discuss...
Abstract: Surface plasmons (SPs) of metallic silver nanoparticles (AgNPs) were investigated in hybrid structures of thin-film reduced graphene oxide (rGO) for light-sensing applications. The near-infrared (NIR) detection of the hybridized structures was demonstrated in two different device configurations. The first one was obtained by spin-coating of the rGO suspended in deionized water on top...
Graphene is an intriguing platform to study exotic quantum transport phenomena due to its intrinsically high mobility and remarkable electronic properties. To achieve high-performance device, graphene is usually encapsulated between thin sheets of hexagonal boron nitride (hBN) to protect graphene layer from extrinsic impurities. Cr/Au is typically employed to make contacts with the edges of...
The requirements of electron transport layer (ETL) for high efficiency Perovskite solar cells (PSCs) are, for example, appropriate band energy alignment, high electron mobility, high optical transmittance, high stability, and easy processing. The metal-oxide ETLs that have been proposed for PSCs are, such as, TiO2, SnO2, etc. TiO2 is usually used for ETL as a...
Ferroelectric polymers are one of the next-generation pulsed capacitor materials for the potential application in capacitive energy storage. This polymer with higher saturated polarization, smaller remnant polarization and higher electrical breakdown are the most promising candidates. In this work, the dielectric properties and energy storage capacity of the bilayer polymers films of...
In this work, we use the latest data of the total flux of cosmic-ray electrons from AMS-02. The AMS-02 data are comprehensive in between a few GeV to TeV. We find a global fit for the electron spectrum. The global fit is a smoothly broken power-law model that is compatible with the observation. We consider a background model for the production of electrons in the Milky Way galaxy. We assume...
Thermoelectric (TE) materials offer a way to convert waste heat energy into electrical power, based on the Seebeck effect. The TE energy-harvesting mechanism of a material is that when a temperature gradient (ΔT) is applied, the charge carriers (electrons for n-type materials or holes for p-type materials) from the hot side diffuse to the cold side. As a result, an electrostatic potential (ΔV)...
As a result of the Fukushima accident in 2011, not only is radionuclides released into the atmosphere, but also large amount of contaminated water are accumulated from cooling water, ground water and rainwater at Fukushima Daiichi Nuclear Power Plant. Over 1 million metric tons of waste water has been contained in steel tanks crammed onto the Fukushima campus 10 years later. The storage...
Second is the SI unit of time, it has been defined as the oscillation of the two-level quantum system. Since 1967, the definition based on the microwave frequency, 9 192 631 770 Hz, between the hyperfine ground state of the cesium atom at a temperature of 0K. The uncertainty of the microwave clock has reached the level of 10-16. The next generation of atomic clock will move from microwave to...
Clusters of galaxies are the largest gravitationally bound objects in the universe, consisting of hundreds of galaxies. However, both theoretical calculations and simulations tend to predict too much cool gas and too many newborn stars. This is referred to as “the cooling flow problem”, and the best candidate for explaining this discrepancy is feedback by the central active galactic nucleus...
The distribution of galaxies in the universe can be studied via several catalogs of galaxy survey. In this research, galaxy sample was collected from the Sloan Digital Sky Survey (SDSS) Data Release 15 (DR15) database. This database contains a huge number of galaxies for studying the extragalactic field, e.g., the physical parameters of galaxies in the cluster, and the large-scale distribution...
A study was carried to investigate the effect of gamma ray irradiation on seed viability of upland rice (Oryza sativa L.) on cultivated method. Long harvesting age and low productivity are the inhibiting factor in upland rice breeding. The objectives of this research were to increased productivity of upland rice using gamma-ray radiation at dose of 0, 20, 40, 60, 80, 100 Gy. The results...
Jupiter’s aurora features have been observed by Hubble space telescope (HST) for over two decades. One of the auroral feature, Ganymede’s magnetic footprint, appears close to the main emission and is sometimes embedded in the main emission. The later case causes confusion in identifying Ganymede’s magnetic footprint from in main emission. The FUV aurora images were taken by Advanced Camera for...
Construction of defect-free or zero-entropy arrays of single atoms is the basis towards synthesizing a fully controlled and scalable quantum system in term of the interaction and a number of interacting systems, which is crucial in some applications such as quantum information processing, quantum simulation, and quantum error correction. By starting with cooled atomic cloud from the technique...
Abstract. This research aims to study of the ancient sea conditions of Sating-Pra Peninsula. Samples of marine mollusks and wood dating by radiocarbon technic. The results showed that marine mollusks at UTM 47N 0647185 0861978 at a depth of +2.00, +1.28, +0.52 and -0.46 m from mean sea level (MSL), the ages are 7,030 ± 360, 6,540 ± 340, 6,630 ± 380 and 10,160. ± 700 years before present...
In quantum field theories, interactions between particles can be studied by using Feynman diagrams. Calculating Feynman diagrams in strong interaction between particles results in infinity values. This problem can be solved by using a process of renormalization that is the method of removing an infinity. Invariances under scaling form a group called renormalization group. Some renormalization...
Quantum physics is the subject that was found difficulties by many university students. It is interesting to know how they understand the meaning of quantum state in many aspects. In this work, we surveyed the student understanding by providing a conceptual test which consisted of open-ended and multiple choices questions. Students could interpret the meaning of quantum state by their own...
While the teacher attempts to guide their students to ‘correct’ ideas, the students brings to bear prior knowledge, their intuition, everyday experiences and conversations/readings when constructing their understandings. The learner goes through ‘wrong’ dead ends, meanders along different alleys; slowly changing and every now and then producing what the teacher delights in hearing. The...
The mixing height, sometimes also referred to as the mixing layer height, the atmospheric boundary layer (ABL) height or the planetary boundary layer (PBL) height, is one of the meteorological parameters that affect particulate matter concentrations on the surface. Its accurate estimation is therefore necessary. In this study, an improvement in the estimation of the mixing height is carried...
In Nuclear quadrupole resonance (NQR), the interaction of the nuclear magnetic moments of quadrupolar nuclei (spin greater than 1/2) with the electric field gradient of the surrounding molecular orbitals produces an energy splitting. Because the resonant frequency is very specific to the molecular structure, the NQR can be used to detect explosive materials very accurately and it is extremely...
As of recent years, triple-cation perovskite solar cells have received immense attention due to its superior efficiency and better stability comparing to the classic single-cation perovskite solar cells such as MAPbI3 or FAPbI3. A triple-cation perovskite layer which has been used most recently is cesium-containing FAPbI3-based perovskite. One of decent...
The searching for the room-temperature superconductors have been one of the most enthusiastic fields in physics. In my talk, I will give an overview and the most recent status of the conventional superconductors under pressure as pressure exceeded that of the earth’s core can be generated in several laboratories around the world. At the present time, the theoretical calculations provide...
The present paper investigates the influence of El Nino and La Nina event year in the South China Sea (SCS) on tropical cyclones (TCs) activity moving on to Thailand. Base on the storm tracking for a period of 69 years (1951–2019) from the Thai Meteorological Department (TMD) was applied to analyze. The results show that during this period the number of 27 El Nino event year and 22 La Nina...
Climate change is currently causing droughts in many parts of Thailand especially in Dan Chang district, Suphan Buri province where many area are out of irrigation coverage and typical groundwater exploration are less successful due to groundwater shortage. Therefore the needs for other shallow groundwater (i.e. less than 15m deep) resources are prominent. This work uses integrated studies of...
This work investigates the interactions between two filaments in fusion plasma. Plasma filament is used to investigate dynamics of plasma and energy transport at scrape-off layer (SOL). They play an important role in plasma particles transport at far from SOL. Their mechanism was discovered during both low confinement mode and inter-ELM phase of high confinement mode by using infrared...
Research on photonic integration using Silicon-based micron-scale optical waveguide for the development of spectroscopic sensing systems for portable and on-field usage has recently received great attention for several applications with the Mid-infrared (Mid-IR) regions [1, 2]. Nevertheless, all most of the previously-reported works are based on laser-based light sources, which might prevent...
Strongly driven magnetic reconnection occurs in astrophysical events and also in laboratory experiments with laser-produced plasma. We have performed 2.5D particle-in-cell simulations of collisions of two high-energy–density plasmas resulting in strongly driven magnetic reconnection that demonstrates significant non-thermal ion
acceleration. Such acceleration is significant only when the...
We present new isochrone fits to color-magnitude diagrams (CMDs) of five globular clusters including NGC 1261, NGC 1851, NGC 2298, NGC 3201, and NGC 4590. We used archival data obtained from the Advanced Camera for Survey (ACS) on board the Hubble Space Telescope (HST). The data of these five globular clusters were collected V and I filters. In this study, the isochrone fitting to globular...
We give a review of holographic conformal defect from AdS/CFT duality via solutions called Janus solutions. Our tool is gauged supergravity in the embedding tensor formalism. Supersymmetric Janus solutions can be obtained by solving BPS equations on AdS sliced-domain wall and generally show a scalar field varying with radial coordinate that is dual to a position-dependent gauge coupling...
We will present preliminary results of the full polarisation of 6.035-GHz excited OH and 6.668-GHz methanol masers towards a star-forming region G351.417+0.645. These are the first OH and methanol observations made in full polarisation using one array and five antennas of the Long Baseline Array (LBA) of Australia, which provided the highest angular resolution measurements of magnetic field...
V781 Tau is the one of W UMa type of the eclipsing binary system which its orbital period is 0.34 days. The 0.7 -meter telescope with CCD photometric system in B and V filters was conducted at the Regional Observatory for the Public, Chachoengsao, Thailand was used for data observation, during December 2018, UT. The Wilson-Devinney Technique was used for calculated the physical properties of...
Abstract
This work aimed to develop the NIMT Line Scale Interferometer System for calibration of line spacing for supporting several industries. The NIMT Line Scale Interferometer System calibrator was the assemble of both checked straightness of stage and the Laser Interferometer System. The straightness of stage sized 400 mm was checked by CERA Straight Master, Model SM-C1000-22, serial...
A simple short-pulse generator circuit based on electronic gates is designed for short electric pulse of about 12.00 ns at Full Width at Half Maximum (FWHM) and 2.96 Volt amplitude for driving a laser diode. Using our circuit with a 780 nm laser diode designed and fabricated for producing short light pulses. The circuit utilizes an AND gate, a XOR gate, and a common function generator,...
Interference and diffraction of light are properties of light studied in the secondary school and university. General interference experiment can display interference pattern as only a light-dark interfering stripe but it cannot be used to studied in depth to the intensity of interference and diffraction patterns. Therefore, the purpose of this research was to develop an experimental set that...
Pearl is an organic gemstone widely popular due to its unique color and luster difference from other gems. Its chemical composition is mainly composed of calcium carbonate (CaCO3) more than 80 %, conchiolin 10 % to 14 % and water 2 % to 4 %. One of the factors determining the quality and price of pearl is the luster. The different lusters of pearls could be related to the different CaCO3...
Nickel oxide microstructures were succesfully synthesized by hydrothermal method. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and Brunauer-Emmett-Teller (BET) isotherm were used to characterize the crystallinity, morphology, surface and porosity characteristics for the sample. The magnetic properties were investigated by vibrating sample magnetometer (VSM)....
Abstract:
The main objective of the present study was to investigate the effect of Fe-coated on magnetocaloric effect (MCE) of Gd foil. The Fe film with thickness 142 nm and 193 nm was grown on both side of 500 m Gd foil using evaporation. Magnetic properties of the samples were investigated using vibrating sample magnetometer. The magnetic entropy change was calculated from the isothermal...
Author: Apiwit Kaewko ,Kittisak Ketaiam
Advisor: Dr. Nithiwadee Thaicharoen
In cold atom experiment, the laser requires to be stabilized at a specific frequency. This can be performed using saturated absorption spectroscopy in a vapor glass cell. Here, the atomic density inside the glass cell has to be high enough in order to extract the spectroscopic signal. One method to...
In this study, phlai slices were dried with three production drying temperatures (50, 60 and 70°C) three lavels of infrared power (500, 1000 and 1500 W) and 0.4 m/s air velocity in a solar dryer combined with intermittent infrared radiation. Distance from infrared source was 20 cm. The initial moisture content of phlai was about 600% (d.b.) and was reduced to the final moisture content of 13%...
To measure the refractive index at a particular altitude of a solution with a vertical refractive index gradient, the transparent wedge-shaped container was constructed altogether with the development of mathematical formula derived from Snell's law. The refractive index of the solution can be calculated by measuring the angles of incoming and outgoing laser beams relative to the respective...
Abstract. In this research, the study to investigate and compare the physical and
mechanical properties of water hyacinth and cogon grass fiber reinforced epoxy resin
composites. The composites were fabricated by hand lay-up process. The effect of investigation
was analyzed via water absorption, microstructure, tensile properties, flexural properties and
impact strength tests for total...
Porous silica nanoparticles were synthesized in this research. TEOS was used as a precursor and three types of surfactant including CTAB, S770 and TTAB, to be used as structure directing agent. To compare the effect of template type on the characteristics of synthetic nanoparticles, molar ratio of precursor to template is equally controlled. The co-condensation combined with a bi-phasic...
Methylmercury, an organic formation of mercury, occurs from the microbial activity mostly in upper sedimentary layers of sea bottoms. It is taken up rapidly by the food web, with greater accumulation in higher trophic levels. Moreover, methylmercury is effectively absorbed (more than 90%) in the gastrointestinal tract of humans, whereas inorganic mercury is poorly absorbed. Eating seafoods...
An amulet, also known as a good luck charm, is an object believed to confer protection upon its possessor. Thai Amulets exist in many forms in Thailand and are made by many different traditions and ethnic groups. Many people in Thailand, Singapore, and Malaysia believe that amulets depicting Phra Luang Pho Thuad hold great protective powers granting safety in times of distress, especially...
MODELING AND SIMULATION OF QUAD BAND RADIO FREQUENCIES ENERGY HARVESTING SYSTEM
Hengswat K., Rojbundit A., Songsriboonsit P., Madlee. S., and Disrattakit.P
Mahidol Wittayanusorn School, Nakhon Pathom, Thailand
s6207940@mwit.ac.th
Abstract
The energy harvesting technique can be used to collect ambient energy and convert it into electric power. This technique is continuously...
According to the most of the low academic achievement of high school students, due to a negative attitude towards physics. The aim of this study is to provide a positive attitude in physics for high school students by the trail and development of a STEM Education lesson in simple harmonic motion. The lessons are divided into 3 parts.
The first part: Instructor provides a basic knowledge of...
The toxic feature of two disparate pore-forming toxins, Cry $\delta$-endotoxins from Bacillus thuringiensis (biopesticide) and CyaA-hemolysin (CyaA-Hly) from Bordetella pertussis (human pathogen causing whooping cough), is generally attributed to their capability to form oligomeric pores, causing target cell lysis. Attempts via multidisciplinary research have been made to provide more...
Marine seismic reflection method is widely used in petroleum industry to map and interpret the potential of petroleum reservoirs. Surface-related multiple reflections are particular problem in marine reflection seismic investigation, as they often obscure reflections from imaging targets. This research demonstrates the effectiveness of the combination of surface-related multiple elimination...
The NARIT Center for Optics and Photonics Laboratory aims at designing, developing and commissioning cutting-edge optical instruments. This, by targeting the following thematics: astronomy, space, remote sensing, microscopy and optical surfaces manufacturing. This center includes two laboratories: the Laboratory for Space and Astronomy (LOSA) and NARIT Astropark (Chiang Mai) and at the...
Owing to its strong light-matter interaction, graphene has been considered the thinnest nanomaterial that could pave the next generation of optoelectronic and photonic applications. Here, we present an experimental consideration of using plasmonic properties of graphene sheets coupled with metallic nanoantennas towards the fabrication of a THz detector. The detection of the photocurrent in the...
Abstract. The research aims to develop the experimental set of the temperature measurement in liquid by Arduino program. The experimental set is composed of 1) 2 liquid temperature sensors (DS18B20 model), 2) Arduino program, and 3) LED screen for showing the temperature value in unit of °C. The experimental set developed by the researcher is measurable the liquid temperature from -55 °C...
The International System of Units (SI), a successor of the Metric System, has been the corner stone of modern metrology since the time of the French Revolution. The SI was revised significantly in 2019. The revision transformed the SI from a unit-based system to a constant-based system. The new SI is defined by a set of seven constants. NIMT has initiated three research projects to research...
Perovskite materials have gained tremendous attention for various applications in optoelectronics due to their charge/photon conversion capability and simple fabrication via solution processing i.e. spin coating, spray coating, dipping coating, and roll-to-roll printing. As precursor inks are in liquid form, doping and compositional tuning are facile. Due to the fact that precursor inks...
ABSTRACT
The study of the period change of V619 Peg was conducted. V619 Peg is an A-subtype of W UMa contact binary. The data was monitored with the 0.7m telescope at NARIT’s Spring Brook Observatory, Australia, in 2019-2020. The time of minima were used to compute the O-C diagram in order to find the system orbital period change and the third body. The results show that the system has an...
Abstract
Nowadays, more than 4,000 exoplanets have been discovered, including a hundred of circumbinary planets. In the following work, the orbital variations of circumbinary planets: planets orbit in the binary star systems, have been studied. Their orbital evolutions for a thousand years were simulated using the REBOUND package. The computed Hill’s sphere and Roche limit of each system...
Vanadium nitride and copper (VN-Cu) films with differing high Cu contents were deposited using reactive magnetron co-sputtering and by varying the nitrogen partial pressure. A literature review, indicated that the Cu content in the films affects the mechanical film properties significantly. The ratio of low Cu in the films can improve the mechanical and electrical properties. A high Cu ratio...
This research project aims to study the effects of PVP and PEG on the morphological structure, hydrophilicity and mechanical properties of PSF/NH2-SiO2 nanoporous composite membranes. To investigate the physical and chemical properties as mentioned above, pure PSF and composite of PSF/NH2-SiO2 membranes with and without the addition of PVP and PEG are fabricated by phase inversion method....
Over the past years, perovskite solar cells (PSCs) have attracted a lot of interest by exhibiting desirable properties like dynamically tunable electronic band structures, suitable electromagnetic waves absorbance, and long charge carrier diffusion length. Moreover, PSCs are also solution-processable, which, when combined with their excellent photovoltaic properties, further heightens the...
Thailand Tokamak I (TT-1), the first tokamak in Thailand, is a small size tokamak, currently under a reconstruction by Thailand Institute of Nuclear Technology (TINT). TT-1 core components, namely vacuum chamber and magnet coils, are previously parts of HT-6M tokamak and are donated from Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), China. Four sub-systems of TT-1 are under...
This study shows the development of the asymmetry of the Crab Nebula through the years and the rate of its expansion in visible wavelength taken by the Hubble Space Telescope. The Rayleigh-Taylor instability is mainly accountable for the existing visible optical filaments which shows the nebula’s asymmetric development is increasing. Images were processed by isolating into quarter sections...
The polymer composites based on the electrostrictive materials with high polarization are attracting scientific due to the prospect of application in the energy conversion. The dielectric and electrostrictive properties of polyurethane (PU) thin films filled with Polypyrrole-Carbon Black (PPy-CB) at different concentrations were investigated. All samples were prepared by using a film-casting...
Frequency evolution of the pulsar’s emission contains information of the emission region and the pulsar’s magnetosphere. The ultra-wideband low receiver (UWL) covering 704 to 4032 MHz recently installed on the 64-m Parkes radio telescope allows us to investigate this topic, which normally requires multiple radio telescopes at different observing bands operating simultaneously. The filterbank...
The objective of this study was to improve student’s understanding and problem-solving skill for high-school students in the topic of projectile motion. This work shows a new but conventional and important representation. We used the column vector to teach grade-10 students at a school in Bangkok in academic year 2020. After finishing the topic of projectile motion, the test was given to 48...
R-symmetry and supersymmetry in abelian gauge Wess-Zumino model are determined to be broken spontaneously. At tree level potential, if R-symmetry is spontaneously broken by generalized O’Raifeartaigh superpotential with a Feyet-Iliopoulos term, gauge symmetry will also be broken. If it does not break, gauge symmetry will be preserved. Therefore, an analysis of the one-loop effective potential...
Thailand Institute of Nuclear Technology (TINT) is setting up the new experimental facility for the first tokamak in Thailand, TT-1, at Nakorn Nayok site. The first plasma is likely to discharge with hydrogen or argon. Some preliminary simulation result suggests that X-rays in a wide range of energy is expected; with most likely be absorbed in the vacuum vessel. During operation, there may...
A pulsar is a highly magnetised neutron star. Misalignment of the rotation and magnetic field axes means electromagnetic radiation is visible from Earth just once per rotation, resulting in characteristic periodicity in observed brightness. Most commonly observed at radio frequencies, the Crab pulsar (PSR B0531+21) is one of only six pulsars known to emit in both the optical and radio...
A radio telescope development kit has been developed to facilitate science and engineering learning in many topics such as celestial sphere and coordinates, stars and blackbody radiation, mechanics and control systems, digital signal processing and programming. This development kit has been designed as a low-cost with a small satellite dish and can be assembled by yourself (or DIY system). Its...
Radioactive isotopes of elements (radionuclides) are naturally present in the environment, and that includes our bodies and our food and water. We are exposed to radiation (also known as background radiation) from these radionuclides on a daily basis. Radiation comes from space (i.e., cosmic rays) as well as from naturally-occurring radionuclides found in the soil, water and air. Radioactivity...
Perovskite solar cells have had rapid growth in their performance and efficiency over just a few years. To achieve high performance, the perovskite absorbers require high crystallinity and good surface morphology. However, the solar cells still ends up as wastes at the end of their life time. The problem is exacerbated by the solar cells’ relatively poor stability where perovskite materials...
Characterization of planetary atmospheres is a rapidly developing area. One method that is commonly used to study planetary atmospheres is transmission spectroscopy, which measures the variation of transit depth with wavelength. The retrieval process is one of important process for retrieve exoplanetary atmospheric parameters. However, the traditional retrieval method (e.g. MCMC and nested...
Abstract
This study aims to experimentally investigate the role of wedge-shape hopper angle on jamming of 2D granular materials under vertical vibration. The cylindrical particles used in the experiment were made from hardwood with a smooth and dry surface. There were 350 particles which were randomly placed inside the hopper whose angles were 10 – 50 degrees and whose opening was 2 and 3...
Rope coiling on a static plane is a circle with full rotational symmetry. The more ordered shapes, hypotrochoids and epitrochoids, arise from the breaking of rotational symmetry induced by the rotation of a plane. Given the sufficiently slow plane frequencies, as feeding velocity is increased the shape deforms from a circle to an epitrochoid and eventually to a hypotrochoid. The onset of...
A rotary magnetic refrigeration (MR) prototype is designed and developed in this work. The numerical simulation of the MR with Gd magnetocaloric materials (MCM) and layered La-alloy MCM were performed to compare the MR performance. The MR prototype consists of (i) the rotary permanent magnet (PM) system, (ii) the active magnetic regenerators (AMR, and (iii) the heat exchange fluid flow...
To reduce the tropical cyclone impact of lives and economics, the precise forecast of the event is required. The weather research and forecasting (WRF) model was applied for simulating typhoon Damrey (2017) caused ravaging of the strong wind, heavy precipitation, flash flood and storm surge over the Indochina region. The simulated duration was 8 days starting from 31 October 2017 00 00 UTC to...
One of the evidence left in the crime scene, which is important in finding the person who committed the crime, is latent fingerprints. Fingerprints are both unique and permanent, making it an ideal biometric trait for the person identification by extracting and comparing characteristic points (minutiae) of ridges. The cases of overlapping fingerprints are frequently encountered in a crime...
There are two interesting lesson sequences for teaching force and motion in high-school physics. These are teaching free-body diagrams before Newton’s laws (FbN) and teaching Newton’s laws before free-body diagrams (NbF). Both sequences were found in physics textbooks. Different authors adopted the sequence that they believe it would affect student understanding better. However, some physics...
The gas tunnel type plasma jet is an effective heat source for thermal processing application such as plasma spraying. The key concept of gas tunnel plasma is its torch configurations, especially the role of the vortex gas flow. This is very important for the stability and energy density of the plasma jet produced. This work studies the flow of gas vortex in 3 dimension using finite element...
We simulate the wave propagation through various mediums using graph-theoretical path finding algorithm. The mediums are discretized to the square lattices, where each node is connected up to its 4th nearest neighbors. The edge connecting any 2 nodes is weighted by the time of flight of the wave between the nodes, which is calculated from the Euclidean distance between the nodes divided by the...
Thailand Institute of Nuclear Technology (TINT) is setting up the first tokamak in Thailand, dubbed as Thailand Tokamak I (TT-1), at its Nakorn Nayok site. Core components of TT-1 are taken from the previously known HT-6M tokamak, donated by Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), China. These core components are furnished with four up-to-date sub-systems. Fueling...
Quantum computation and quantum sensing harness properties from individual atoms and electrons. The nitrogen-vacancy center in diamond is among the most prominent candidate as a building block for quantum control, and especially quantum sensing due to its atomic size and the ability to operate under ambient conditions. We demonstrate the use of a home-built confocal microscope for probing...
We have studied the distribution energy of the single pulses of PSR B1822-09 using the data from Parkes radio telescope in Australia observed from May 2012 to April 2014. The pulsar profile has three components including main pulse, inter-pulse, and precursor. The study shows that the main profile component is sometimes log-normal distributed. Most of the results show that the energy is normal...
This article is about designing and building single-axis solar tracking system referring to the sun position database. The objectives are as follows: 1. To design and build solar tracking system 2. To compare the power produced from the solar tracking system with stationary solar panel. The angle of the solar panel from the built solar tracking system was positioned with constant altitude...
This paper presents how smartphones determine the speed of sound (a) with a classroom explanation and demonstration to design a variety of lab instruments. Smartphone sensors such as mics and speakers were used as experimental tools by students for calculating the value of speed of sound. Mathematics is used to describe physics principles using only the mean of repetitive experimental results....
Siam Photon Source (SPS) has been operating and providing synchrotron radiation to users for more than a decade, leading to growing user community in South East Asia region. This gives rise to higher demand of a new 3 GeV light source. The new machine, SPS-II, could provide synchrotron light with higher photon energy and higher brilliance than the existing 1.2 GeV machine. Hybrid multi-bend...
A spin density functional study of structural and electronic properties of LiMnO2 doped with different transition metals (Sc, V and Tc) is reported. The physical properties of LiMnO2 material are sensitive with the transition-metal dopants. Transition metal dopants increase the lattice parameters and their volumes, thus increasing the Li diffusion channel. The computations remark that the...
This study aimed to investigate student understanding of graphs in simple harmonic motions using eye-tracking technique and an interview. Twenty-three university students participated in answering 11 multiple-choice questions, adopted from Somroob & Wattanakasiwich (2017). Students’ responses and visual attention were recorded by an eye tracker and they were interviewed to provide reasoning on...
The goals of science are to understand natural phenomena and to explain how they may be changing over time by described the workings of the universe. However, many natural phenomena are extremely complex and may never be fully understood in terms of physical laws. The teaching concepts of energy and heat are difficult for teachers because the students are not able to link kinetic theory and...
One problem of learning Electrostatics is that students often learn by using their common-sense beliefs about electric force and electric field. This study investigated students’ conceptual understanding of finding electric force, electric field and electric potential from a point charge after learning an introductory physics course We administered the Electrostatics Conceptual Evaluation Test...
The $b\rightarrow sll$ ($l=e, \mu$) transition is a flavour-changing neutral current process that mediates through one-loop penguin or box diagrams. The decay is considered to be a good probe for the New Physics as particles predicted in the beyond Standard Model theories can enter into the loop. The exclusive decay $B\rightarrow K^{(*)}l^{+} l^{-}$ was first observed by the Belle experiment,...
The dynamics of the plasma in the scrape-off layer (SOL) is important for understanding complex behavior of tokamak plasmas because it determines heat exhausted to the plasma-facing components. This will subsequently regulate the amount of impurities released from the surfaces. Furthermore, it has been demonstrated in simulations and experiments that the transport in the SOL region is not...
The local structure information in dielectric materials could be investigated by a combination of X-ray Diffraction (XRD) and Synchrotron X-ray Absorption Spectroscopy (SXAS) techniques. In this work, Pb(Zr,Ti)O3 crystals were investigated for their local structure information under the influence of temperature and electric field. The X-ray Absorption Near edge structure (XANES) and Extended...
The principle of synchrotron-based spectromicroscopy techniques, sample requirements, typical measurement, and data analysis is presented. Particularly, the combination of photoemission electron microscopy (PEEM) and near edge X-ray absorption fine structure (NEXAFS)/X-photoelectron spectroscopy (XPS) is a spectromicroscopy technique using synchrotron light source to characterize the chemical...
This research aims to synthesize a silica xerogel from rice straw ash that is a residue biomass from agriculture. The first step of the synthesis is preparing of sodium silicate that is then used as silica source. To prepare a silica source, pretreated rice straw was burned at 600-900 oC to obtain a rice straw ash. Resulted rice straw ash is reacted with 0.5 M NaOH for 3-12 h and filtrated by...
Platinum is a precious metal widely used in the jewelry industry due to its property and intrinsic value. The different particle sizes of platinum can be applied in various applications, especially for jewelry production. In the present article, submicron, and nano platinum particle sizes were synthesized through simple chemical reduction methods and the effect of pH variation was revealed....
Magnetic reconnection is ubiquitous in astrophysical plasmas. It serves as one of the most effective mechanisms to convert magnetic energy into the kinetic energy of particles. Such energy conversion can result in extreme particle acceleration as in solar flares. In many astrophysical environments, the collisional mean free path and the collision time can be much larger than the related length...
Archaeological dating is crucial in archaeology as it is a key to understand human history. However, traditional dating methods used by archaeologists such as potassium-argon dating and luminescence dating can provide ambiguous age results, e.g., noise disturbance or argon loss during the dating return young apparent ages. Therefore, I plan to establish an archaeomagnetic secular variation...
Abstract
The objectives of this study were to study the output efficiency of n-type and p-type Bi2Te3 thermoelectric materials (ingot) for applying as a thermoelectric generator (TEG). The phase analysis of Bi2Te3 was performed by X-ray diffraction (XRD). The results indicated that most diffraction peaks of the XRD patterns of Bi2Te3 sample present a rhombohedral Bi2Te3 structure. The...
The biggest problem faced by plasma torch operation is the corrosion of electrodes. The effects of corrosion will lead to material loss and a short lifetime of plasma operation. To overcome this problem, the corrosion behavior of electrodes by plasma arc is investigated using Comsol simulation. The plasma arc is generated based on breakdown voltage following the Paschen curve. The five...
The simple pendulum experiment is a basic experiment in high school and first year university physics class. In the experiment, we always use small-angle approximation to approximate that the simple pendulum will become a simple harmonic motion. This research aims to measure angle and length of the simple pendulum which the small-angle approximation can still be used. The angles of pendulum...
The polywell fusion reactor is smaller than other types of fusion reactor. Its concept arises from a combination between cusped magnetic confinement and inertial electrostatic confinement. This work uses numerical simulations to investigate the effects of magnetic field topology resulted from various configurations of the polywell fusion device, i.e. cube configuration (6 coils), dodec...
Abstract: We present the fabrication of carbon nanotube-silicon (CNT/Si) hybrid photodetectors and their electrical characterizations at ambient temperature under the illumination of a halogen lamp. The hybridized structure of the CNT/Si junction created in this work showed rectifying behavior of a p-n junction diode with a finite-bias voltage across the junction. By using the hydrophobic...
MnO2 nanoparticles were synthesized by the facile one-step hydrothermal method. The structural and morphological properties of the samples were investigated by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Brunauer-Emmett-Teller (BET) was used to study the surface area and pore structure of MnO2 nanoparticles. The XRD results confirmed the formation of pure...
Abstract
The effort of this work is in order to exploit the utilization of the 3D printing process in physics classroom as active learning. However, only the 3D printing paradigm may not qualitatively sufficient, the Open approach paradigm has been also incorporated. Since the 3D printing process is just a method that making a physical object from the creative idea to a 3D digital model,...
Learning science, especially in the physics field, there are many varieties of invisible and abstract phenomena that are hard and difficult for students to observe and learn. One of the tools that can help students to understand those phenomena in a better way is computer simulations. The computer simulations are usually used in both on-site classroom and on-line learning platforms. Learning...
The FT-IR spectroscopy is a significant method to detect the heat treatment of gemstones, especially, ruby and sapphire. There are set of certain peaks i.e., 3309, 3232, and 3185 cm-1 in the FT-IR spectra using as an indicator to determine whether the samples have been undergone heat treatment. In this study, however, new evidence has emerged. The O-Al-O bending vibration peak at the...
The research aims to develop the photometric law of distance experimental set using the light sensor Arduino for measuring the luminous intensity. The experimental set consists of 1) the light sensor based on the GY-302 BH1750FVI module of Arduino board displaying values in Lux unit on the LCD, 2) 12- Volts DC power supply, 3) one-meter length aluminum track, and 4) a manual book. It is used...
Piezoelectric material is a type of ceramic that has electrical properties. When it is subject to mechanical force, the piezoelectric material provides a voltage known as piezoelectric effect. This commonly uses piezoelectric which is known as KNN (K1-xNaxNbO3) due to high curie temperature. KNN can also be used to apply in many ways. In this research, we studied further about the physical...
The efficiency of a radio telescope decisively depends on its pointing accuracy. Telescope's pointing model (PM) contains repeatable errors due to the antenna control system's imperfections, which can be corrected during observation. The 4.5m Small Radio Telescope (SRT) has been developed for education and experiments, at Astropark, National Astronomical Research Institute of Thailand (NARIT),...
Microwave leakage from a microwave oven door can interrupt the functions of electronic devices and endanger human health. The harmful radiation leaking from the oven front door has to be blocked but the visible light is still allowed to be transmitted. The door design is based on the frequency selective surface (FSS) because of the filter behavior. In the simulation, a proposed FSS of...
Very High Energy (VHE) Gamma-rays from Active Galactic Nuclei (AGNs) can interact with the infrared photons from the Extragalactic Background Light (EBL) and start electromagnetic cascades. In case that the extragalactic magnetic field near a host galaxy is strong enough (~1 micro G), the cascades would develop isotropically around the AGN, and electron/positron pairs created along the...
The metal polyhydrides have attracted considerable attention because they can evolve into a superconductor with a high value of critical temperature (Tc) under pressure. In this research, we have investigated structures of MgH2, MgH3, and structures that substitution of deuterium instead of hydrogen under pressure 0-300 GPa to determine the stability of structure under high pressure so that it...
The strongest solar flares of solar cycle 24 of interested was on September 6, 2017, and it was the number 8 strongest solar flare since 1996. This extreme solar flare in 2017 occurred at the minimum of solar cycle 24. The active region are located in the western hemisphere and produced the violent explosion class X9.3 and X2.2 on September 6 , X1.3 on September 7, and X8.2 on September 10,...
During impact events, planetary crusts experience high pressures that can impart rocks with shock remanent magnetisation (SRM) if an ambient magnetic field or demagnetise rocks if a field is absent. If rocks experience substantial impact heating or are pressurised above ~40 GPa (inducing melting and recrystallization) they may instead record a thermo-viscous remanent magnetisation (TVRM) as...
Fusion Reactions can release a huge amount of energy per reaction and still be clean with no greenhouse gases emission. An alternative energy source of CO2-free and at gigawatt scale production such as fusion energy is on sought to strengthen the electricity stability of our country. Thailand Institute of Nuclear Technology (TINT) has initiated a newly established department on Plasma and...
The objective of this research is to investigate the synthesis of porous single-phase nano-titanium using titanium (IV) isopropoxide (TTIP) as a precursor and three types of surfactant as structure directing agent or template; CTAB, MTAB and Sugar Ester S770. Co-condensation method combined with bi-phasic condition is utilized for the synthesis. The formation of titanium nanoparticles occurs...
This study proposes an approach for non-contact moisture inspection in dried food products, which is crucial to maintain optimal quality and shelf-life, using terahertz signal intensity and thickness of a test sample. To achieve this, a sample-specific calibration curve needs to be determined first. The HAITAI crackers were chosen in this work for demonstration purposes. Four different stacks...
Deep Learning (DL) has empowered computers with superior performance in modern Natural Language Processing (NLP) tasks, such as sentiment analysis and machine translation. Even for texts with long-range correlations such as sequences of characters in Wikipedia, DL can effectively express the power-law decay in the mutual information between two distant characters. Despite empirical successes,...
This research presents two axes solar cell system tracking by 3-sensor. Motion according to the sun's position is based on fuzzy logic control principles based on the light intensity of the LDR (Light Dependent Resistor). Sun tracking to make solar cell systems get higher wattage, when compared with fixed solar cell systems. Principle of control using a fuzzy logic based on the method of...
Radio Astronomy is one of essential probes in the era of multi-messenger astronomy to research various astronomical phenomena and understand their evolution in the universe. In particular, very-long-baseline-interferometry (VLBI) technique in radio wavelengths is very unique, enabling us to achieve the highest spatial angular resolution in the world of 1 milliarcsecond or higher. Observations...
We aim to compare upper limits on dark matter annihilation by different measurements of cosmic-ray electrons and positrons in the solar neighbourhood. We focus on dark matter annihilation into electron-positron pairs. The propagation of electrons and positrons is described by a diffusion-loss equation. We consider energy loss processes such as inverse Compton scattering, synchrotron radiation...
Since the COVID-19 pandemic in 2020, the working patterns have been changed to be online platforms. People tend to spend plenty of time sitting in front of their computer. During this period, wrong postures may involuntarily and frequently occur. This causes a rising number of office syndrome and backache patients. This project therefore aimed to create a warning system for wrong posture...
Stable oxygen isotopes in terrestrial archives such as e.g. speleothems or tree rings are commonly used to reconstruct past variations in precipitation. However, although rainfall on historical time scales appears to show a reasonable correlation to yearly averaged stable oxygen isotope values, the actual mechanisms behind this correlation are complex. To improve our understanding of the...
