SCIENCE AND TECHNOLOGY NAKHON SAWAN RAJABHAT UNIVERSITY JOURNAL

Evaluation of the Integral \int_{0}^{y} \frac{tanh(x)}{x} dx; y\geqslant 1 from BCS Theory in Analytic Form via Numerical Convergence Method.

Chanun Sricheewin — 2025-10-14

In the weak-coupling limit of superconductivity BCS theory, the energy-gap equation near the transition temperature involves the integral where providing =Boltzmann constant and is the transition temperature parameter of this superconductor, and represents the Debye frequency of the normal-metal lattice associated with this superconductor. This integral is not simple to evaluate since its upper limit is not a constant but a variable. So far, there exists a pure analytic method to carry out this integral but complication arises. One has to deal with intuitive integration by parts and infinite series of Dirichlet Eta function. In this article we devise a new method using simple analytic and numerical techniques to carry out the integral. Based on a remarkable mathematical property that the hyperbolic tangent function may be approximated as unity for large , we replace with the new function of 2 domains separated by a critical parameter named between which the function takes the value of hyperbolic tangent function and unity. Suitable yields the correct integral. We call this “numerical convergence method”. Both techniques yield the same result, i.e. . This result was employed further to find the ratio Cooper pair binding energy/.

Extraction and Physicochemical Characterization of Thunbergia laurifolia Lindl. leaf Pectin

Premjit Rongsawat — 2025-07-25

The purpose of this research was to study pectin extracted from dried Thunbergia laurifolia Lindl leaves with difference acid type solution i.e. acetic acid, hydrochloric acid, nitric acid and sulfuric acid) adjusted pH 3. Pectin extracted from dried leaves had an extraction percentage in the range of 0.15±0.07 - 0.33±0.16%. The pectin extract employing sulfuric acid solution adjusted pH 3 had the highest amounts of galacturonic acid, esterification percentage, and methoxyl, measuring 52.86±1.72 mg/g, 32.64±1.20%, and 5.40±0.07, respectively, while commercial pectin had the value of 91.27±0.73 mg/g. 45.07±0.26 and 7.35±0.04%, respectively. These results indicated that our pectin belonged to the group of low levels of esterification and methoxyl pectin as well as the extracted pectin was analyzed by Fourier Transform Infrared spectroscopy, which revealed the present of –OH –CH –COOH –COOCH₃ and –COO^-functional groups corresponding to the commercial pectin. Therefore, it was concluded that the substances extracted from dried T. laurifolia leaves using various acids at pH 3 was pectin.

A System for Evaluating Food Stalls according to Food Sanitation Regulations through a Web Application.

Pattarawadee Junthaworn — 2025-07-29

Currently, the evaluation format of food stalls of Health Center 3 uses a paper for evaluation, resulting in a large amount of paper, making it difficult to collect data, causing delays and wasting resources. In addition, incorrect processing or data loss may occur. This study aimed to investigate requirement patterns and develop a food stall evaluation system based on food sanitation regulations. The research began with data collection from documents and related studies, followed by interviews with 11 executives and staff members from Health Center 3. The collected data were analyzed to identify system requirements. The interview results indicated that users desired a system with the following features: a home screen, evaluation criteria, policy guidelines, report results, a contact us section, registration functionality, and a login portal for staff to conduct evaluations. Next, the data were analyzed using an object-oriented approach, including use case diagrams, class diagrams, and activity diagrams. The system’s interface was then designed and developed using Sublime Text 3 as the primary editor, MariaDB for database management, and HTML5, CSS3, JavaScript, and PHP 7.4.8 for programming. After development, the system was tested and evaluated by 24 users. The results showed that users were highly satisfied with the system’s performance, with a mean satisfaction score of 4.30 (standard deviation = 0.72). This suggests that the system effectively supports Health Center 3 staff and assessors in managing evaluations. Executives could also access evaluation reports more conveniently and efficiently. Additionally, the system was user-friendly and accessible across smartphones, tablets, and desktop computers.

Plankton Community Structure in Naruebodindrachinta Reservoir, Prachinburi Province

Vichaya Gunbua — 2025-10-10

This study aimed to analyze the structure of the plankton community in the Naruebodindrachinda Reservoir, Prachin Buri Province. Samples were collected from 9 stations in October 2021, January 2022, and May 2022. Phytoplankton samples were collected with a 20-micrometer net by filtering 10 liters of water, while zooplankton samples were collected using a 175-micrometer net dragged vertically for 5 meters. A total of 6 divisions and 44 genera of phytoplankton were found, including the division Chlorophyta (green algae) with 22 genera, Cyanophyta (blue-green algae) with 11 genera, Euglenophyta (euglenoids) with 3 genera, Pyrrhophyta (dinoflagellates) with 3 genera, Chrysophyta (chrysophytes) with 3 genera, and Bacillariophyta (diatoms) with 2 genera. The Chlorophyta division was the dominant group with the highest number of genera (22 genera), and an average density of 344,460–371,293 cells per liter. As for the zooplankton, 3 phyla and 5 groups were found: the phylum Arthropoda (Copepod, Cladocera, and Ostracod groups), the phylum Protozoa (Vorticella group), and the phylum Rotifera (Rotifer group). Cladocera was the dominant group, with an average density of 12,476–23,486 individuals per cubic meter. The diversity and density of plankton tended to vary with the seasons, reflecting the influence of changing environmental factors over time.