Journal of Physics and General Science

Monitoring Gamma Radiation Levels in the Ambient Air Surrounding Songkhla Rajabhat University: A Study from June to November 2022

Pitchpilai Khoonphunnarai — 2024-08-15

This study aims to assess ambient gamma radiation levels (ambient gamma dose rate) in the air surrounding Songkhla Rajabhat University and evaluate potential risks associated with these levels. Utilizing a portable airborne gamma radiation meter, specifically the Thermo Scientific RadEye G-10 Gamma Survey Meter, measurements were conducted daily from June to November 2022 across all buildings within the university campus. Analysis of the collected data revealed ambient gamma dose rate ranges of 0.04-0.37, 0.04-0.36, 0.04-0.36, 0.04-0.35, 0.03-0.34, and 0.02-0.33 microSv/hr for June through November, respectively. The average ambient gamma dose rates for each month were calculated as follows: 0.125±0.057, 0.132±0.054, 0.135±0.055, 0.128±0.052, 0.120±0.051, and 0.115±0.050 microSv/hr, respectively. These values were found to be within normal levels, falling below the recommended range of 0.05-0.20 microSv/hr by the Office of Atoms for Peace. Consequently, the ambient gamma dose rate in the air surrounding Songkhla Rajabhat University poses no harm to staff, students and the people.

Prediction of Moisture Content in Boesenbergia rotunda (L.) Mansf. Using an Artificial Neural Network Model

Tawedach Mundphukhier — 2024-08-15

The objective of this research was to develop a method for predicting the moisture content of Fingerroot (Boesenbergia rotunda) dried using a solar dryer, by employing an artificial neural network (ANN) model, which is known for effectively predicting various quantities under complex conditions. Experiments were conducted under general sky conditions in May 2024 to gather input data for the model. The ANN was trained using data from the first four rounds of experiments, comprising 148 data sets, and was tested using data from the fifth round, consisting of 37 data sets. Each data set included measurements of solar radiation intensity, relative humidity of the air, air temperature, and moisture content of the Fingerroot. The ANN model that most accurately predicted the moisture content had a structure of three hidden layers, each with eight nodes. The predicted moisture content from the ANN model was compared to actual experimental values, showing a close match with a predicted final moisture content of 5.65 % (wb) and an experimental value of 5.97 % (wb). The model's performance was evaluated with a Root Mean Square Error (RMSE) of 5.0388 and a Mean Bias Error (MBE) of 4.2015. These results demonstrate that the ANN model can accurately predict the moisture content of solar-dried Fingerroot, providing a reliable tool for optimizing the drying process.

Development of an Application for Managing Grants for Ban Khuan Community Members

Wikanda Plychum — 2024-08-15

The objectives of this research were to develop an application for managing grant for Ban Khuan community members and to evaluate user satisfaction with the implemented system. The development languages and tools used were PHP, HTML5, CSS, JavaScript, and the Ionic framework, with MySQL employed as the database management system. The system operated in two main components: (1) Officers: Accessible via a web application, officers could manage member and family information, record and manage death toll information, oversee member collections, handle grant delivery data, manage notification information, and generate summary reports. (2) Members: Through a mobile application, members could check payment transactions. The system could send notifications via LINE for quickly informing members of news. The questionnaire employed in this study collected data from a group of 30 users with a specific sampling method, comprising 5 staff members and 25 community members, regarding their satisfaction with the system's usage. The mean satisfaction score was 4.59, with a standard deviation of 0.54.

Synthesis of Carbon Nanotubes by Chemical Vapor Deposition on Stainless Steel 304 Substrate

Habeebah Alee — 2024-08-15

This study explores the synthesis of carbon nanotubes (CNTs) using chemical vapor deposition on stainless steel 304 (SS304) substrates. The SS304 substrates were first treated with 37 % hydrochloric acid for 0, 5, 10, and 15 minutes. Subsequently, CNT synthesis was carried out at temperatures of 700, 800, and 900 °C, with a 99.99 % ethanol flow rate of 330 ml/min for 2 hours. The optimal conditions for CNT synthesis were a temperature of 900 °C, with the SS304 substrate immersed for 5, 10, and 15 minutes. The resulting CNTs were multi-walled and exhibited tip growth.

A Study of Zinc Ion Adsorption Efficiency Using Banana Peel Tannins Immobilized on Broussonetia papyrifera (L.) Vent Pulp

Punyanuch Thammaacheep — 2024-08-15

The aim of this study is to investigate the adsorption capacity of zinc ions using a tannin-based adsorbent. Tannin was extracted from fresh banana peels and subsequently immobilized on Broussonetia papyrifera (L.) Vent pulp. The adsorption capacity of the adsorbent for zinc ions was determined using Atomic Absorption Spectroscopy (AAS). Results showed that an adsorbent weight of 1.50 g and a contact time of 90 minutes yielded the highest zinc ion adsorption percentage at 95.37 %. The prepared adsorbent demonstrated the ability to adsorb zinc ions in the concentration range of 1-10 ppm, with adsorption capacities ranging from 0.08 to 0.86 mg/g. The adsorption isotherm for zinc ion removal was described by the Freundlich model, with experimental data yielding values for K, n, and R² of 0.47, 0.85, and 0.99, respectively. Therefore, it can be concluded that the tannin-immobilized Broussonetia papyrifera (L.) Vent pulp adsorbent is effective in removing heavy metals and holds promise for developing applications in wastewater treatment.

Effect of Solid-to-Solvent Ratio on Efficiency and Shelf Life of the Chromosome Staining Dye Extracted from Fox Grape (Causonis trifolia (L.) Mabb. & J. Wen) Fruits

Oranut Sukanan — 2024-08-15

The objective of this research is to extract natural dyes from the fruit of grape, Causonis trifolia (L.) Mabb. & J. Wen, with the aim of replacing the use of expensive acetocarmine. Concentrated acetic acid was used as the solvent at sample-to-solvent ratios of 1:1, 1:3, and 1:5 (g/ml) for a duration of 24 hours. The extracted dyes were subsequently stored at 4 °C for further analysis. Dyes with varying shelf lives of 0, 7, 14, 21, and 28 days were subjected to tests assessing chromosome staining efficiency and anthocyanin content using the pH differential technique. The research findings indicated that the natural dye extracted at a 1:1 ratio exhibited the best chromosome staining and the highest anthocyanin content, with effectiveness decreasing for the 1:3 and 1:5 ratios, respectively. Notably, the dye extracted at the 1:1 ratio demonstrated chromosome staining capabilities comparable to those of acetocarmine. Furthermore, the quality of the dye was maintained for at least 28 days when stored at 4 °C. Therefore, the 1:1 ratio proved to be the most effective for extracting chromosomal dyes from fox grape fruits, establishing it as a viable substitute for acetocarmine.

Annual Effective Doses Due to Radon in Consumer Water Supplies in the Phuphi and Khao Niphan Mining Areas, Surat Thani Province, Southern Thailand

Phattharasuda Rodprapai — 2024-08-15

In Ban Na San District and Wiang Sa District of Surat Thani Province, gypsum and anhydrite are mined. This area also has a relatively high surface concentration of uranium, directly impacting radon gas levels in the environment, particularly in water sources for consumption, potentially causing health risks. Therefore, this research aims to study the physical characteristics of water, measure the concentration of radon gas in water, and evaluate the annual effective doses from radon due to ingestion and inhalation from water sources used for consumption around the Phuphi mining area in Ban Na San District and Khao Niphan in Wiang Sa District, Surat Thani Province. A total of 30 water samples were obtained from tap water, groundwater, canal water, and mine well water. The research results found that the average temperature, pH, electrical conductivity, dissolved solids, salinity, dissolved oxygen, and background radiation doses were at levels of 30.2±0.9 °C, 6.21±0.93, 0.06±0.07 S/m, 0.31±0.37 g/L, 0.31±0.37 ppt, 7.60±0.12 mg/L, and 1.2±0.3 mSv/y, respectively. The concentration of radon gas in water ranged from 5.54±1.02 Bq/L to 53.79±3.62 Bq/L, with an overall mean value of 27.74±14.51 Bq/L, exceeding the U.S. EPA standard limit for radon contamination in drinking water (11.1 Bq/L). When comparing the average radon gas concentration, the Phuphi mining area had 31.69±15.82 Bq/L, while Khao Niphan had 23.79±12.33 Bq/L. It was found that there was no statistically significant difference at the 0.05 level. Additionally, the mean radon gas concentration in groundwater (45.90±6.35 Bq/L) was higher than in canal water (33.34±12.09 Bq/L), tap water (26.36±5.28 Bq/L), and mine well water (6.64±0.70 Bq/L), respectively. The evaluation of the total annual radiation dose from ingestion and inhalation showed an average of 75.73±39.60 μSv/y, which is lower than the WHO recommended reference level of 100 μSv/y. However, the average annual exposure to radiation from ingestion and inhalation of groundwater (125.31±17.33 μSv/y) was found to be higher than the reference level. Despite other water sources having values below the reference level, it is recommended not to drink water directly from these sources in the study area without standard treatment for drinking water.

Assessment of Natural Radioactivity Levels of (226Ra, 232Th, 40K) in Rice Samples Collected from the Provinces of Phatthalung, Surat Thani, Phang Nga, Krabi, Chumphon and Narathiwat

Kunracharin Sithong — 2024-08-15

This study investigated the concentrations of natural radionuclides—226Ra, 232Th, and 40K—in 10 samples from three rice varieties: fragrant rice, brown rice, and riceberry rice. The samples were collected from the provinces of Phatthalung, Surat-Thani, Phang Nga, Krabi, Chumphon, and Narathiwat. Analysis was performed using a high-purity germanium (HPGe) detector and gamma spectrometry system at the Nuclear Physics Laboratory, Faculty of Science and Technology, Suratthani Rajabhat University. Calibration was conducted with the IAEA RGU-1 standard reference material, and each sample underwent measurement for 18,000 seconds. The results indicated that the specific activity concentrations of the natural radionuclides ²²⁶Ra, ²³²Th, and ⁴⁰K ranged from 1.48±0.07 to 4.81±0.62 Bq/kg, less than the minimum detectable activity (MDA) by 4.81±1.13 Bq/kg, and 6.85±0.02 to 63.51±0.18 Bq/kg, respectively. The average concentrations were 3.01±0.97 Bq/kg for ²²⁶Ra, 2.76±2.06 Bq/kg for ²³²Th, and 29.46±22.22 Bq/kg for ⁴⁰K. When assessing the annual effective dose from rice consumption, the total mean value was found to be 84.66±8.24 µSv/y. The annual radiation dose from rice consumption found in this research is below the safety limit established by the United Nations Scientific Committee on the Effects of Atomic Radiation (290 µSv/y; UNSCEAR, 2000). Therefore, it can be concluded that the radiation exposure from consuming rice in this study is within safe limits.

Utilizing Pineapple Leaf Fibers to Improve the Sound Absorption Properties of Natural Rubber Materials

Darika Jaaoh — 2024-08-15

This study focuses on developing sound-absorbing materials from natural rubber compounded with pineapple leaf fibers (PALF) to enhance sound absorption efficiency and reduce noise pollution in various environments. The research employs physical and mechanical methods to analyze the properties of wall panel foams incorporating varying amounts of PALF. Increasing the PALF content influences the material's density and sound absorption characteristics. The panel containing 3 parts per hundred rubbers of PALF, at a 1.5 cm thickness, demonstrates the highest noise reduction coefficient of 0.36 ± 0.13. Additional analyses include density testing yielding 0.72 ± 0.02 g/cm3, energy absorption of 86.7 ± 6.8%, and acoustic property evaluation using a single microphone method across various frequencies. The results show that PALF significantly enhances the low-frequency (500 Hz) sound absorption performance of natural rubber foams, achieving a sound absorption coefficient of 0.43 ± 0.07. These findings underscore the potential of natural materials in creating sustainable environments and mitigating environmental impacts.