Journal of Applied Research on Science and Technology (JARST)

WO3/Bi2WO6 photoanode enhancement for photoelectrocatalytic water oxidation; scan rate effect optimization in the cyclic voltammetry deposition method

2023-09-28T10:17:35+07:00

The photoelectrocatalytic approach is a very efficient technology for eliminating microorganisms and organic contaminants. The development of photoanode is widely recognized as a crucial approach to enhancing the efficiency of photoelectrocatalytic cells. The key goal of this methodology is to enhance the efficacy of photoelectrocatalytic oxidation by optimizing composited photoanode fabrication. This research development focuses mainly on fabricating composite WO₃/Bi₂WO₆ semiconductor thin films with high water oxidation efficiency and favorable photoelectrocatalytic E. coli degradation applications. Cyclic voltammetry was utilized to create WO₃/Bi₂WO₆ thin coatings on conducting glass while optimizing the photoelectrocatalytic activity via the scan rate parameter. The characteristics of the developed electrode, including charge transfer resistance, optical properties, morphology, crystal structure, chemical composition, and oxidation numbers, were investigated to improve photoelectrocatalytic activity. It was observed that the scanning rate significantly influenced the characteristics of the WO₃/Bi₂WO₆ electrode and the photoelectrocatalytic activity on water oxidation. It was discovered that the WO₃/Bi₂WO₆ electrode prepared with a scan rate of 25 mV/s exhibited the greatest photoelectrocatalytic water oxidation as well as distinguishing characteristics from other conditions. The decision to utilize decreased scanning rates has been determined to optimize the reaction kinetics and improve the film-forming properties of WO₃/Bi₂WO₆. Significantly, the developed electrode can also be used to eliminate 87.5% of E.coli in 15 minutes via a photoelectrocatalytic catalytic mechanism. The photoanode composed of WO₃/Bi₂WO₆ has promising capabilities in removing microorganisms and organic pollutants, making it a viable candidate for future advancements in wastewater management applications.

Efficiency of wastewater treatment from environmental laboratory of science and technology, RMUTP using ozonation

2023-11-01T11:28:59+07:00

Wastewater from the laboratory in the Division of Environmental Science and Technology, Faculty of Science and Technology, Rajamangala University of Technology Phra Nakhon is a source of pollution without any treatment. Researchers realized that it would become an environmental problem in the future. For this reason, wastewater treatment from water laboratory would be studied using ozonation process because the researchers want to use the existing equipment in the laboratory and a simple technique that the students can do. This aims to treat the wastewater until it passes the water standard. The laboratory's wastewater characteristics were unclear based on the study. The pH values measured were 8.15, 3.35, and 2.49, respectively. COD levels were monitored of 10,480, 2,400, and 3,040 mg/L, while the measured BOD values were 4,649, 1,683, and 2,200 mg/L, respectively. Additionally, the SS concentrations were 682, 788, and 548 mg/L, respectively. Because of these characteristics using only the biodegradation process didn’t work. The ozonation techniques were a good option following the research objective. The results showed that the suitable condition for the ozonation process was pH6 and the optimal time was 40 minutes. Because after 40 minutes the COD removal increase only 5% but after 60 minutes the ozonation had no effect on COD removal. This condition was applied before using biological treatment via a sequence batch reactor (SBR). Using microorganisms and 8 hours of aeration via SBR, the efficiency of COD BOD and SS removal was only 41.66, 0 and 71.82 percent, respectively. Filling ozone in rate 0.25 gram/hour/liter wastewater with SBR reactor, the wastewater treatment efficiency increased. It can remove COD, BOD and SS of 63.15, 50.00 and 72.63 percent, respectively. The advantage of this research was that the ozone generator can be applied for wastewater treatment without additional costs.

Optimizing pick-place operations: Leveraging k-means for visual object localization and decision-making in collaborative robots

2023-12-01T18:10:48+07:00

This article presents an approach to object localization algorithms for pick-place operations in collaborative robots by utilizing conventional color segmentation in computer vision and k-means clustering. Adding the k-means clustering algorithm complements the color segmentation by distinguishing and grouping the sections of similar pixels; hence, object localization is more accurate. The order of pick-place operations of each cluster acquired from the proposed algorithm is prioritized based on norm. Integrating the proposed framework provides a well-structured depiction of the localized objects, which is fundamental for successful pick-place operations. The TCP/IP communication framework via socket communication is established to facilitate data transmission between the robot and the host computer. The objective is to ensure that the robot's end effector performs as directed by the host computer by obtaining information on the pick-and-place operation, including the localized coordinates, dimensions, the order of operations, and the pose of the objects of interest to the robot. In this experiment, a cobot arm is employed to autonomously pick and place objects with different shapes and colors in a workspace filled with diverse objects, requiring the robot to choose the closest objects to operate based on the data from the host computer. Our results demonstrate the effectiveness of this integration, showcasing the enhanced adaptability and efficiency of pick-place operations in collaborative robots. This study indicates 98% accuracy in pick-and-place operations with an average latency of 0.52 ± 0.1 s, indicating an improvement compared to the traditional algorithm without k-means clustering, which achieves an accuracy of 88%. Additional studies reveal that when incorporating pose estimation into the pick-place operations, the proposed algorithm's accuracy is 94%. The demonstration highlights the potential of leveraging machine learning algorithms and computer vision from the camera to perform flexible pick-place operations via socket communication.

Improvement of heat-sealing strength of chitosan-based composite films and product costs analysis in the production process

2023-11-28T17:39:54+07:00

The primary objective of this study was to enhance the heat-sealing strength of composite films made from chitosan and analyze the associated product costs. The approach adopted involved formulating chitosan-based composite films by incorporating gelatin and green seaweed extract. This strategic combination resulted in a notable improvement in heat-sealing strength. The ensuing attributes underwent meticulous examination, encompassing seal strength, FTIR spectroscopy, FE-SEM surface morphology analysis, and DSC thermal properties determination. Data analysis was rigorously conducted using the SPSS program, with outcomes presented as mean values accompanied by standard deviations. Disparities were discerned at a 95% confidence level, ensuring statistical robustness. The findings unveiled that the incorporation of 10% gelatin and 1% green seaweed extract substantially enhanced the seal strength of the chitosan-based composite films. Notably, the introduction of green seaweed extracts disrupted interactions between chitosan's structure and various molecular vibrations. This disruption, coupled with increased ionic interactions and hydrogen bonding, led to improved molecular interdiffusion, ultimately resulting in modified heat sealability. The study identified the optimized conditions as 10% gelatin and 1% green seaweed extract concentrations, which produced the highest seal strength at 19.4 N/m. Further evidence from scanning electron microscopy demonstrated improved interfacial adhesion, attributed to the adjusted surface morphology. The film surface did not contain small scattered particles and presented a smooth phase. This suggests that the chitosan-based composite achieved good interfacial adhesion between the two components in these films. As an essential aspect for practical application, the total production cost of the films was determined to be 606.84 baht. This information renders the data collection from the study valuable for companies seeking to enhance production efficiency and overall profitability.

Preparation of poly(methyl methacrylate)-zinc oxide hybrid nanoparticles via miniemulsion polymerization

2023-12-10T15:20:03+07:00

The encapsulation of zinc oxide (ZnO) nanoparticles with poly(methyl methacrylate) in the presence of triethylene glycol dimethacrylate (TEGDMA) as a crosslinking agent was synthesized by the miniemulsion polymerization technique. The ZnO as a catalyze was varied from 1 wt% - 7 wt%. Several techniques were used to analyze the PMMA/TEGDMA/ZnO hybrid. The morphology and particle size distribution of the PMMA hybrid was observed using a field emission scanning electron microscope (FE-SEM). The diameter of the PMMA/TEGDMA/ZnO hybrid was in the range of 57 nm to 115 nm. The morphology of the PMMA/ZnO hybrids was sphere-shaped with a narrow particle size distribution and no agglomeration of the hybrids occurred. The encapsulation and crystalline structure of the PMMA ZnO hybrid were determined using a high-resolution transmission electron microscope (HR-TEM). The HR-TEM image demonstrated that the ZnO was encapsulated in the PMMA hybrid. In addition, the high magnification of the TEM image demonstrated the lattice spacing of ZnO and the diffraction mode image presented the crystalline structure of ZnO. Therefore, the photocatalytic properties of the PMMA/ZnO hybrid were examined via the degradation of methylene blue (MB) solution under dark and UV-A irradiation. It was found that the photocatalytic activities of the PMMA/ZnO hybrid increased when the ZnO content increased up to 7 wt%. The maximum MB degradation for PMMA/TEGDMA/ZnO 7 wt% and PMMA/ZnO 7 wt% were 80.1 % and 77.6 %, respectively. Thus, the photocatalytic efficiency of the PMMA/ZnO increased in the presence of TEGDMA as a crosslinking agent.

The development of association rules for student performance analysis using FP-Growth algorithm as a guideline for multidisciplinary learning

2023-11-14T08:34:17+07:00

This study aims to develop association rules for student performance analysis using the FP-Growth algorithm. The data used for developing the association rules comprised 107 student reports. The reports, voluntarily provided by 107 junior high school students, consisted of student achievement results across 8 subject areas: Thai Language, Mathematics, Science, Social Studies, English Language, Computing Science, Visual Arts, and Home Economics. The data was applied to developing association rules using the FP-Growth algorithm towards WEKA, a machine learning software. The research team designed the process consisting of the following 5 stages: data collection, data preparation, model formulation, model evaluation, and model application. After achieving the association rules, the research team applied them to the prototype development of a student performance analysis system for promoting students' academic excellence. The system could be operated by Android mobile phones. According to the research results, the association rules developed by the algorithm provided a confidence level of 92%, and a rule of 7 rules will be generated. The findings indicated the correlations between the subject areas, which shared similar individual students' academic achievements (≥ 80 scores). The association rules could be applied to the multidisciplinary curriculum planning, which benefited students and promoted academic excellence. For example, by applying Rule, it could be assumed that students who earned 80 scores or higher in the English subject would likely earn identical scores from their Thai Language class. Therefore, they could effectively learn to integrate English and Thai languages. To illustrate, students may be asked to translate song lyrics from English to Thai, serve as tourist guides or translators, or even give welcome speeches to foreign guests.

Development of Samed mushroom (Boletus griseipurpureus Corner) crackers and quality study during storage

2024-01-26T17:59:36+07:00

The objectives of this research were to develop cracker products using pre-treated Samed mushrooms in three variations (boiling water, brining, and soaking in herbal water), assess the proximate composition, evaluate their chemical and physical properties, and assess the quality of Samed mushroom crackers during storage. The proximate composition of fresh Samed mushrooms (per 100 g) revealed moisture of 92.08 g, carbohydrates of 2.60 g, protein of 3.37 g, ash of 0.81 g, fat of 0.23 g, and fiber content of 0.91g. The energy content was 29.59 kcal/100 g. The proximate composition of Samed mushroom crackers per 100 g indicated the following: carbohydrates 69.25 g, crude fat 24.08 g, protein 4.36 g, ash 1.82 g, and moisture 0.49 g. Additionally, the energy content was 511.6 kcal/100 g, with sugar and sodium contents measuring at 0.91 g and 552.3 mg/100 g, respectively. The study on the different types of pre-treatment solutions for Samed mushrooms demonstrated that pre-treatment by soaking in herbal water received the highest acceptance from consumers, with an overall liking score of 8.97. In the development of Samed mushroom crackers, the appropriate ratio of Samed mushroom to fish was 15 to 85. Regarding the microbiological quality changes during a 30-day storage period, the study revealed that the total viable count was <10 CFU/g, yeast count was 7.0 CFU/g, Bacillus cereus count was <100 CFU/g, Staphylococcus aureus count was <10 CFU/g, Clostridium perfringens count was <100 CFU/g, and Escherichia coli count was 3.0 CFU/g. In terms of chemical quality, the peroxide value was 0.57 meq/kg which is consistent with the Thai Community Product Standard (Cracker 107/2011). Storage for 30 days found that the condition of adding nitrogen gas resulted in the finding of less microorganisms than in a normal atmosphere, along with conditions for adding oxygen absorbers together with desiccant.

Development of an innovative wireless power transmission model for marine applications

2024-02-20T11:28:09+07:00

The conventional wired charging system for ship-to-shore charging of underwater vehicles is prone to specific problems related to unreliable connection mechanisms and safety. The wireless charging system overcomes the danger of electrocution, as the power is transferred from the shore to the ship via electromagnetic induction instead of traditional ways of transferring AC power in the marine environment. This paper presents a novel system-level modeling and designing of wireless power transmission for marine applications. The proposed system comprises three main components: (a) a shore-side mobile transmitter (Shore-SMT), (b) an onboard static receiver, and (c) another ship-side mobile transmitter (Ship-SMT). The Shore-SMT and Ship-SMT, each consisting of a circular array of magnets, rotate in the vicinity of the receiver with a fixed circular variety of coils, resulting in voltage induction in the receiver coil. Consequently, the induced voltage in the receiver coil charges the onboard batteries. COMSOL® MULTIPHYSICS environment is used for the modeling and simulation of the proposed system using finite element method (FEM). The test cases simulate the individual and mutual rotation of the transmitters at several distances from the receiver coil. A prototype of the model is also developed. Experimental results from the developed prototype show promising performance as the percentage of transferred voltage increases from a single layer of x9 coil and x9 magnet bars to 70-75% and 80% in a double layer of x9 Ferro bars with x9 winding coils and double-sided x12 magnets and x9 winding coils respectively. It proves to be a better alternative to the conventional methods used for Ships and Vessel charging.