Additive manufacturing can produce near-net-shape permanent magnets with varying geometries. Interestingly, the magnetic properties of 3D-printed alloys from selective laser melting were comparable to those of conventional sintered and bonded magnets with the same compositions. The fuse filament fabrication successfully printed strontium hexaferrite were with high magnetic loadings in...
Jeerasak Phooarphit¹, Ekkarat Pongophas¹, Tossaporn Lertvanithphol², Kittidhaj Dhanasiwawong², and Mati Horprathum²
¹Division of Physics, Faculty of Science and Technology, Thammasat University, Pathum Thani 12120, Thailand
² National Electronics and Computer Technology Center, Pathum Thani 12120, Thailand
Corresponding author: e_pong@tu.ac.th
The apparatus is based on the blade coating...
In general, a simple harmonic motion is studied by measuring and recording the time required for the bob to complete a cycle. In addition, many experiments use smartphone or motion sensor to measure the motion. This method requires the installation of additional equipment into the system, and thus the moment of inertia of the system involves in those devices. In this study, we present the new...
Oscillations have been well-studied in many branches of physics due to their periodic behavior and the solution compactness of the solutions, which allows a variety of applications. In addition to electromagnetic or mechanical oscillation experiments usually available in the university or high school physics laboratories, the setup that undergraduate students can explore the oscillation of...
An easy-to-setup experiment designed to measure period and air drag coefficients of damped pendulums is reported. The setup is made up of a solid metal ball and cylindrical shells with various sizes to create air drag. The ultrasonic position sensor (HC-SR04) and an Arduino Uno board was located at the lowest point of motion. The pendulum was released from the same height with small angles....
Raman spectroscopy is a set of techniques based on Raman scattering properties, widely applied to analyze the composition of various substances. The techniques consist of 1) Backscattering, which collects Raman signals scattered from the surface of a sample; and 2) Transmission, which collects Raman signals transmitted by the surface of a sample in the opposite direction of a light source...
Using of bio-based plastic products is one of popular solution for reducing environmental problems. Bio-based plastics is combination of bio-based carbon (have radioactive carbon isotope) and fossil carbon (no longer have radiocarbon remaining), accordingly, radiocarbon or carbon-14 in plastic product comes from bio-based carbon. Identification of bio-based content in plastic products is...
Climate change and global warming are main global problems. Greenhouse gases are released from various human activities, including agricultural practices from open burning in the field. Sugarcane leaves combustion generated air pollution problem during dry season every year. This research aims at balancing carbon in sugarcane field to consider carbon released from sugarcane leaves burning and...
Recently, plasma activated waters (PAW) have been investigated intensively for sustainable agriculture and post-harvest technology. The waters can be used effectively as green fertilizers, decontamination agent and green pesticides, while no harmful by products left over[1-2]. The acidic characteristics of the PAW, resulted from nitrate and hydrogen peroxide, can produce high germination rate...
Freely suspended smectic films of a few molecular layers thick is a model system that can be used to study two dimensional phenomena. In our study, smectic C film was drawn across a few millimeter hole and stabilized under strong surface tension that can suspend 5CB nematic liquid crystal droplets sprayed onto it. Thermal fluctuation of liquid crystal molecules is observed across the smectic C...
The quality of education is one of the UN sustainable development goals. Nowadays, greenhouse gas emissions have escalated to record levels and there are concerns in urgently finding sustainable methods to reduce carbon to avoid climate change and to reduce greenhouse gas emissions (GHGe). Studying in SLR lab, indirect lighting demonstration is one of the important topics where paper is...
To improve student understanding about an image formed by a concave mirror, 2 demonstration kits were developed. One kit is used to view images formed, and show how to locate and find the image distances and sizes. The other uses a laser beam to show the incident and reflected light rays and relate to the ray diagram normally used to find the image location. The demonstration kits were applied...
Solar power generation from photovoltaic panels is likely to increase in the future, especially in rural areas where the power grid is inaccessible. Over time, such systems are subject to deteriorate due to environmental conditions, as well as the current and voltage systems. If not properly maintained, the photovoltaic panel may deteriorate faster than normal. This research aims to design and...
Thai glutinous rice, khao tan rice cracker herbal is a popular Thai traditional snack, which is economically important for local entrepreneurs in Mahasarakham province, Thailand. Drying process is an important step in acquiring good quality for final products. The main scope of this research is to assess the feasibility of using the heat demand – temperature function for heat demand forecast....
Optical coherence tomography or OCT is an optical imaging technology that is capable of high-speed three-dimensional cross-sectional imaging of samples, such as biological samples as well as other transparent media, at high resolution. Most importantly, OCT can be operated at a light wavelength in near-infrared region with a low illumination power of a few milliwatts. Therefore, OCT is a...
The human resource development is very important issue for Thailand Institute of Nuclear Technology (TINT). TINT has established education and training programmes on active learning about nuclear reactor and reactor experiments using the PC-based basic principle simulator. This simulator provides efficient hands-on learning of the reactor operation and reactor experiment related to reactor...
The increase in demand for renewable materials and strict regulations on organic waste are pushing the food packaging industry toward more sustainable alternatives. Agricultural waste, namely, rice straw and sugarcane residue, is one of the promising replacements for the traditional synthetic polymer in food packaging applications because of its biodegradability, low cost, and low carbon...
Nowadays, cancer is well known that it cause the most disease of human death. Chemotherapy or direct uptake of anticancer drugs was generally employed for cancer treatment. To ease the risk of normal cells and side effects of patient, nanocarrier contained anticancer drug and contrast agent is continuously developed to increase the survival rate. Theranostic agent is a multifunctional...
Monitoring of groundwater fluctuations is mandatory in order to evaluate the groundwater resources and develop groundwater management solutions. In particular, the area has intensively groundwater demand such as the upper Chao Phraya River basin. We have developed an automated groundwater level measurement system that integrates the real-time measurement system, automatic data transfer, data...
The 30 kW DC plasma torch system with the well-type cathode (WTC) has been developed to generate thermal plasma above 1200 0C, which is adding the external magnetic coil on the cathodic part of the torch. The well-type torch is hollow cylindrical copper’s 5 mm thickness, whose cathode electrode and anode electrode was 150 mm in each length, the diameter is 22 mm through the center, The gap...
The classification of sex of a newborn chicken is crucial for optimizing the cost of chicken meet production. The current classification technique relies on visual inspection by human naked eyes, which required years of training to expertise. There is no commercially available gender-classification tool for newborn chicks. Recently, a new optical imaging technology for cross-sectional imaging...
The objective of this study was to investigate the effects of three drying temperatures (55, 60, and 65 °C) on the quality attributes of green banana flour (color change) and process variables (drying time, rate of drying). The banana was used in ripeness stage 2 (green with a trace of yellow). Experiments were conducted using far-infrared power of 3000 watts. The drying process reduced the...
The objective of this study aimed to investigate the effect of vermicompost on organic rice production. The experiment was conducted at Posai subdistrict, Sri-somdet district in Roi-Et province and Maung district in Maha Sarakham province. The experimental design was Randomized Complete Design (RCD) with 3 replications. The experiment consisted of 6 treatments as followed: 1) Rice berry...
Cancer has become the main leading cause and reason of death worldwide. Chemotherapy is the most common cancer treatment by using anticancer drugs. However, its treatment is limited by its high toxicity to healthy tissues, causing undesirable side effects. Accordingly, research has combined drugs with nanocarriers, especially gold nanohybrids (AuNHs), to achieve better therapeutic effects....
Electrolyte drink becomes very popular nowadays that drinking aid in rehydration which mostly contain water, sugar, and electrolytes (Na, K, Mg, Ca ions). In this work, several electrolyte drinks including M sport, M-plus, Sponsor, Sponsor citrus, Gatorade were analyzed by electronic tongue comparing to mineral and tap water. Non-specified electrode array used in electronic tongue was...
Elemental composition including P, Mg, K, S, Cl, Ca, Zn, Mn, and Fe in rice samples cultivated from Phatthalung, Nakhon Si Thammarat, and Songkhla provinces using a simple, rapid and non-destructive wavelength dispersive X-ray fluorescence (WDXRF) spectrometry. A good agreement was achieved between the certified and measured values with the recoveries higher than 94%. The repeatability was...
The objective of the study was to estimate the rainfall from the amount of water vapor in the air. The relationship between the upper air data and the surface data from 2007 to 2017 was used to create a mathematical model at the same station to determine the amount of water vapor. The findings indicated that, the relationship has a relatively high level of reliability, the correlation...
In this research, optimum tilt angles for south-facing surface obtaining the highest solar energy in Nakhon Pathom (13.82 N, 100.04 E) and Chiang Mai (18.78 N, 98.98 E) stations were estimated for monthly, seasonal and annual basis. The solar radiation incident the inclined surface consists of beam radiation, sky diffuse radiation and reflected radiation. Liu & Jordan (1962) model and Iqbal...
We provide a method for evaluating the feasibility of monitoring or estimating island activities carried out by dredgers and support boats in the Spratly Islands region using VIIRS Boat Detection data, salient to other countries having their claims, especially the Philippines. From 2012 to 2020, an annual summary grid for VIIRS Boat Detection was utilized to compare the number of VBD...
The actual stress measurement is important to the studies in soil mechanics. The sensor that measures the stress must be thoroughly designed and assessed with the soil medium since the soil-structure interaction is complex and depends on many factors. This article presented the design and fabrication of the diaphragm type of soil stress sensor with the built-in amplifier and compared the...
Basketball is a very technical sport, one of the techniques used among athletes is spinning the ball to further influence the ball’s path. This experiment will be studying the height of the ball when throwing with different spin, namely back spin, top spin, and no spin. Heights of the bouncing balls dropped was captured by an iPhone 12 camera and analyzed by an open video analysis software...
Isotropic and anisotropic are type of materials, which is considered from the structural nature of the material with a symmetry and asymmetry structure, respectively. The structure can affect the optical properties of different materials. Due to the symmetrical structure of the material, there will be no effect on the incident polarized light, different from asymmetrical materials. It affects...
Bees are well known as social insects with divisions of labor. In a dark beehive, it was long thought that communication within the hive was based on chemical signals. However, specific sound signals have been identified, and science is beginning to decode what the bees are signaling in the beehive. This work has developed a sound frequency monitoring system from native bees (*Apis cerana...
Moina macrocopa culture using plasma activated water (PAW)
Nichanan Neamtad$^a$, Chokchai Yatongchai$^b$ and Sureeporn Sarapirom$^a$*
$^a$Applied Physics, Faculty of Science, Maejo University, Chiang Mai, Thailand, 50290
$^b$Program of Materials Science, Maejo University, Chiang Mai, Thailand, 50290;
*Corresponding author Email Address: ssarapirom@gmail.com
Water flea...
In May and June 2021, Cyclone Yaas and Tropical Storm Koguma caused high rainfall in various parts of Thailand. The precipitation samples during this period were collected on a daily from six rain gauge stations in the southwest, north, and northeast. All samples were analyzed with cavity ring-down spectroscopy, CRDS which is a highly sensitive spectroscopic technique. The stable isotope...
Online learning is necessary and challenging to develop effective teaching strategies to support student learning during the COVID-19 period. This course has seven students. Some essential equipment is sent to students by post. We demonstrate a simple experiment on the resonance frequency in the LC circuit with a simple metal detector circuit based on a 2n2222 transistor. In principle, Metal...
Gamma irradiation is the one method of green environmental synthesis without further treatment waste. Carbon dots are optical nanomaterials in the carbon family with excellent properties such as tunable fluorescence emissions, biocompatibility, non-toxicity, water-soluble and photo-stability. Therefore, this research used gamma irradiation for carbon dot synthesis at room temperatures. The...
Radiative cooling (RC) is natural phenomenon in which an object passively cools itself by highly radiating mid-infrared waves to the cold outer space (temperature 3 K). The delignified wood (DW), in which light-absorbing lignin compounds in woods are removed from natural wood, shows promising performance of daytime radiative cooling (DRC). The drying of DW with hot pressing is usually...
There have been many studies in physics education research showing that students have difficulties with the buoyant force topic. One difficulty is that students do not understand that the buoyant force is the resultant force of the fluid pressure. This work designed a worksheet based on the question-answer teaching method aiming to help students understand the concept. This method asks...
Proton Computed Tomography (pCT) is an imaging technique used to determine the location of cancer. This equipment simplifies the treatment planning process in proton therapy. The rotation stage is a significant part of our pCT prototype. It can rotate the object 360 degrees for use in the 3D image reconstruction process. The purpose of this work is to design a rotation stage capable of...
In this study, the specific activities of natural radionuclides in 22 rice cultivated soils collected from 5 districts in Nakhon Si Thammarat province, southern Thailand were measured. The measurements were conducted using a high-purity germanium (HPGe) detector and gamma spectrometer at Thailand Institute of Nuclear Technology (Public Organization). The specific activities of 238U, 232Th, and...
Modern analysis for absorbed of organic chemistry is very popular both in industrial laboratories. In general use a UV-VIS spectrophotometer, which a light source for gas. Each wavelength can be measured with high precision but UV-VIS spectrophotometer dispersing Devices system complex light. To import from abroad the country and most expensive because of advances in the development of a LED...
Straightness measurement is an important parameter of dimension metrology. It is widely used in various instruments and machines especially in the industrial segment such as rulers, CNC machines, theodolites and infrastructures. At the moment, there are not have high performance straightness measuring system in Thailand because there is no approved calibration system. This leads to a...
Plasma activated water (PAW) and gamma radiation has intensively been used in many agricultural applications which includes increasing the germination rate, promoting plant growth. However it is important to pay attention to the both effect of PAW and gamma radiation to study the detailed characteristics of chemical composition of tap water and distilled water stimulated by plasma and gamma...
The impact force exerted by falling chains was investigated using a plastic cup attached on the top of a force sensor. Two different linear mass densities of the chains with mass of 0.1452 and 0.1956 kg/m was examined by releasing one meter of their lengths from rest with the lower end just touching at the bottom of the plastic cup. The force sensor was connected with LabQuest and the sample...
The main propose of the present study was to study the forming of sugarcane tissue in order to produce a sugarcane leaf lamp. To obtain a soft tissue of the leaf, the leaf residues were mechanical and chemical processed similar to that of making a sheet of mulberry paper. After that, the tissue was formed as a cone shape by a forming machine which was developed specially for this work. The...
In physics laboratory, an experimental result along with its uncertainty is meaningful to allows other people making judgment about the quality of the experiment. This is the important skill for high-school physics teachers. This study aimed to investigate physics laboratory skill; in particular, measurement and uncertainty. Data were obtained from pre-service science teachers, pre-service...
In this research the Turtlebot2 robot is equipped with the ReSpeaker Mic Array sound sensor infacing through the ROS (Robot Operating System) and using Dialogflow. It works from the Google Cloud Platform and helps convert voice messages into variables for data processing with TurtleBot2. The Kinect is replaced by Lidar to improve the quality of map creation and automatic navigation. The...
The aim of this research was developed for agriculture by using internet technology to control plant growth factors with automation. Plants are planted in greenhouses to facilitate control of various factors affecting plant growth. A greenhouses dimension of 2 meters width, 3 meters length, 2 meters high, and the volume is 10.5 cubic meters. The greenhouses are covered with plastic to prevent...
In quiet environments, the inner ear of vertebrates can produce low-intensity sounds that are detectable in the ear canal, termed spontaneous otoacoustic emissions (SOAEs). This production of acoustic energy has been regarded as an epiphenomenon of the active processes performed by hair cells – the sensory receptors of the auditory system. Experimental measurements of SOAEs emitted from the...
This article presents a smartphone and Arduino microcontroller-based AC circuit educational module focusing on the measurements of an alternating voltage, frequency, phase difference, and a phasor diagram. A smartphone provides a signal generator as a signal source, the Arduino UNO R3 working for signal acquisition, and the beadboard RC series circuit as a test circuit. In-house developed...
This research aimed at studying the effect of the solvent ratio on chemiluminescence that has been widely applied in glow sticks. Dichloromethane and ethyl acetate were used as solvents. The fluorescent solution was the mixture of diphenyl oxalate solvent and fluorescent dye rhodamine B that was stimulated by 405-nanometers laser for fluorescent spectrum measurement before the...
The conversion of heat to spin current is well known as spin Seebeck effect (SSE). In this study, we constructed the cost-effective instrument for measuring SSE by varying permanent magnetic field with angle and distance. The magnetic field strength and temperature gradient were also performed. We measured the spin Seebeck effect, anomalous Nernst effect, spin Hall effect and anisotropic...
Cryptocurrency is a decentralized payment tool that generally does not require any government backing or intermediary. Currently, there are a large number of low-fee exchanges for buying and selling cryptocurrencies with less restrictions. However, the pricing behavior of this highly-dynamic type of market and driving factors for changes of market prices remain unclear. The cryptocurrency...
In this work, we investigated traffic flow simulation of bi- lane systems through the two traffic light signal positions based on the Nagel–Schreckenberg (NS) model, which is well-known as a Cellular Automata (CA) traffic flow model. In the CA model, time, position, speed and acceleration of vehicle are discrete variables. The speed of vehicle is defined as the discrete lattice (cell) number...
