https://jst.vn/index.php/etsd Journal of Science and Technology - Technical Universities Hanoi University of Science and Technology en-US Engineering and Technology For Sustainable Development 3093-3242 https://jst.vn/index.php/etsd/article/view/1116 In the paper, we present for the first time an experimental study on the pyrolysis of oily rags collected from an automobile factory. The performance of pyrolysis to recycle fresh and used wipes to valuable liquid and solid products was compared. The presence of waste lubricant oil (WLO) on fabric drastically changed the outcome of the process. The specific surface area of pyrolytic char was initially reduced, but can expand to 1178 m2/g after activation. A very high fraction of oily rags (75.03 wt.%) was converted to high heating value pyrolytic oil (30.3 MJ/kg), resulting in 22.73 MJ recovered from one kilogram of raw material-higher than from most other waste reported. Gas emission from pyrolysis of WLO contaminated wipes was only 6.09 wt.% of raw materialnearly twentyfold less than incineration and ninefold less than pyrolysis of uncontaminated wipes. Overall, pyrolysis of oily rags produced a considerable amount of valuable material and fuel while releasing little greenhouse gases to the atmosphere, making it an eco-friendly and economically feasible solution for this kind of industrial waste. Xuan Son Nghiem Kim Ngan Ta Anh Tuan Vu Wen Paul Liu Minh Thang Le Copyright (c) 2025 35 5 001 008 10.51316/jst.186.etsd.2025.35.5.1 https://jst.vn/index.php/etsd/article/view/1120 A UPLC-MS/MS was developed for the analysis of 11 pesticides in Vietnamese cannon eggplant. Pesticides were extracted by QuEChERS and then cleaned up with solid phase extraction. 11 pesticides in the sample solution were separated by reversed phase column and detected by positive ionization mass spectrometry utilizing with multiple reaction monitoring (MRM). Validation of the developed analytical method was performed by linearity range, limit of detection (LOD), limit of quantification (LOQ), repeatability, recovery, etc. LOD and LOQ ranged from 0.03 μg/kg to 0.1 μg/kg and 0.11 μg/kg to 0.33 μg/kg for wet weight samples, respectively. Repeatability and reproducibility of the analytical method were achieved below 12.3% and 19.1%, respectively. Recovery ranged from 75.5% to 86.6%. Matrix effect was investigated and presented. The validated analytical method was then applied to analyze 11 pesticides in five Vietnamese cannon eggplant samples. Experimental results indicated that some pesticides were detected in the samples analyzed. However, the concentration of these compounds was below the Vietnam Ministry of Health and EU standards. Tung Quang Tran Thi Hong An Vu Hong Quan Do Thi Phuong Anh Nguyen Thi Diu Pham Thi Hong Nguyen Tuan Duong Vu Van Hoi Bui Duc Nam Vu Manh Ha Nguyen Hoang Anh Nguyen Dinh Binh Chu Copyright (c) 2025 35 5 009 016 10.51316/jst.186.etsd.2025.35.5.2 https://jst.vn/index.php/etsd/article/view/1122 The study aims to evaluate the influence of L-glutamic acid content on the degradation of modified PVA materials and PEG-porous modified PVA materials, based on previous research, was investigated. To assess the biodegradation, measurements such as mass analysis were employed to evaluate the weight loss of the materials. In addition, SEM was utilized to analyze the morphological changes, and FT-IR spectroscopy was applied to monitor the variations in functional groups. The results showed that the PVA-c-Glu material was degraded by 24-32% after 150 days. For the PVA-c-Glu/PEG material, the mass loss ranged from approximately 25-46% after 150 days due to the addition of pores. Based on the SEM observations, significant surface changes were detected, which were attributed to microbial colonization forming clusters on the material surface. Moreover, the FT-IR results indicated that the signals corresponding to functional groups were attenuated after degradation. Thi Hoa Huyen Doan Hoai Nam Truong Thi Thu Hang Nguyen Hong Ngoc Nguyen Vo Huy Trong Tran Kim Thanh Do Huu Tuan Minh Nguyen Quynh Nhu Vu Thi Luyen Tran Quang Tung Tran Thi Thuy Tran Copyright (c) 2025 35 5 017 024 10.51316/jst.186.etsd.2025.35.5.3 https://jst.vn/index.php/etsd/article/view/1123 Research on developing a simulation model to determine fuel consumption (FC) of motorcycles using bio-ethanol and gasoline based on real-world operational data. A computational model was developed using the AVL-Cruise tool to simulate FC. The accuracy of the model was validated using experimental data from a chassis dynamometer test under the WMTC (World Motorcycle Test Cycle). The results show that the model can closely replicate realworld FC. When comparing the simulated and experimental FC data, the coefficient of determination R² was 0.8778, the root mean square error (RMSE) was 28.70 mg/s, and the root mean square percentage error (RMSPE) was 22.89%. Additionally, 67.27% of instant FC data points had deviations within 20%. The model was then used to simulate FC for motorcycles using gasoline and bio-ethanol under four-speed profiles collected from four representative urban areas in Hanoi. The simulation results indicate that when using bio-ethanol, FC was increased by around 13.12%, while energy consumption (EC) was decreased by 24.84% due to differences in the properties of the two fuels. This confirms the advantages of bio-ethanol when used in internal combustion engines. Duy Tien Nguyen Duc Khanh Nguyen The Truc Nguyen Copyright (c) 2025 35 5 025 033 10.51316/jst.186.etsd.2025.35.5.4 https://jst.vn/index.php/etsd/article/view/1124 Deep hole drilling remains a persistent challenge in both research and industry due to high friction and inadequate chip evacuation, which leads to inefficiencies. This study evaluates the efficiency of deep drilling using ultrasonic vibration-assisted drilling (UAD) by comparing it with conventional drilling (CD), with specific energy consumption (SEC) as the primary metric derived from torque measurements. Here, SEC is defined as an accumulated function integrating energy consumption over the entire drilling process, mitigating non-linear and stochastic variations common in deep drilling. Experiments were conducted on Al-6061 aluminum alloy under continuous dry drilling conditions, with variations in spindle speed, feed rate, and hole diameter. The results demonstrate that UAD significantly improves drilling efficiency compared to CD. Specifically, the SEC value for UAD was approximately 21.44% to 77.74% lower than that for CD across all experimental conditions. Moreover, with optimized parameters, UAD achieved a 25% increase in material removal rate (MRR) and a 33.4% reduction in SEC compared to CD. These findings highlight UAD’s potential to enhance deep hole drilling efficiency, offering promising applications for industrial machining processes. Ngoc Hung Chu Copyright (c) 2025 35 5 034 042 10.51316/jst.186.etsd.2025.35.5.5 https://jst.vn/index.php/etsd/article/view/1125 Research on PCB-138 treatment is always urgent, along the development of nanotechnology has created general conditions to apply them in this treatment process. With low cost and easy synthesis of Fe/Cu and Fe/Ni bimetallic nanoparticles, the hydrodechlorination (HDC) reaction was conducted to convert PCB-138 in aqueous media into non-toxic or less toxic products. The study results revealed that the optimal conditions for achieving high PCB-138 conversion efficiency were: [Fe/Cu] = 2,0 g/L, pH = 3; [Fe/Ni] = 2,0 g/L, pH = 7, with a reaction time of 120 to 180 min required to reach adsorption equilibrium. Experimental data indicated that the adsorption of PCB-138 followed a pseudo-second-order kinetic model, confirming a chemisorption mechanism on the surface of the catalytic nanoparticles. Furthermore, the conversion pathway of PCB-138 was proposed, involving the formation of less toxic products such as biphenyl, thereby demonstrating the efficacy of the HDC reaction. This study highlights the practical potential of bimetallic nanoparticles in treating water contaminated with chlorinated organic compounds. Hong Son Nguyen Van Hoang Nguyen Thanh Hung Nguyen Ngoc Toan Vu Copyright (c) 2025 35 5 043 049 10.51316/jst.186.etsd.2025.35.5.6 https://jst.vn/index.php/etsd/article/view/1126 The study addresses the environmental impact of fast fashion and garment waste by exploring the development of sustainable, multifunctional fashion. The research aims to reduce excessive consumption while maintaining both aesthetic and functional appeal. It focuses on transformation techniques, such as adjustable cuts, detachable elements, and convertible features, to enhance garment versatility and extend product lifecycles. By analyzing fashion trends among youth, a group with significant influence over fashion markets, the study identifies key stylistic preferences and integrates them into the design process. Additionally, the research investigates using recycled materials and refined tailoring methods to promote eco-friendly production practices. The results reveal that these designs offer unique, adaptable fashion items that align with sustainable trends, combining diverse styles and high functionality. The study demonstrates that flexible, reusable designs can encourage consumers to make more sustainable fashion choices, reducing textile waste while still allowing for creativity and self-expression in clothing. By promoting multifunctional garments, the research highlights the potential for fashion to contribute to a circular economy, where longevity, adaptability, and eco-consciousness are prioritized in consumer habits. This approach not only offers practical solutions to environmental concerns but also supports the broader shift towards sustainable fashion. Khanh Trang Le Thi Kim Lien Dang Thanh Thao Nguyen Thi Thu Nguyet Vu Copyright (c) 2025 35 5 050 058 10.51316/jst.186.etsd.2025.35.5.7 https://jst.vn/index.php/etsd/article/view/1134 The article focuses on the simultaneous influence of sealing technology factors: sealing temperature, sealing speed, and roller pressure on the quality of the sealing seam, which is evaluated through the tensile strength, the elongation of the sealing seam in the pre- and post-aging conditions and the waterproofing in the finishing process of office raincoat from 100% polyester coated fabric. In this research, authors used orthogonal experimental design method, Microsoft Excel 2010 and Design Expert 11.0 software to process and analyse experiment results. The result is identified sealing technological factors having important effects on the waterproofing, the tensile strength, and the elongation of the sealing seam, and the optimal sealing technology mode to improve the quality of bonding pieces' surface, to increase the aesthetic and durability of the product before use, in the process used; save time and costs in production. The result of this study is a useful guide in the actual production of raincoat garment enterprises in general and the raincoat of 19-5 One Member Limited Liability Company in particular. Study on the Optimal Sealing Technological Regime for Making Officer Rain Clothes Thanh Thao Phan Nguyen Thi Thanh Huong Copyright (c) 2025 35 5 059 068 10.51316/jst.186.etsd.2025.35.5.8 https://jst.vn/index.php/etsd/article/view/1135 The study explores the factors influencing the willingness to try (WTT) novel alternative protein (NAP) products among consumers aged 18-25 in Hanoi, Vietnam. Anchored in the Theory of Reasoned Action (TRA), the research examines the roles of health concerns, environmental and sustainability concerns, price, novelty, and subjective norms in shaping attitudes and WTT toward NAP products. Data were collected through a structured questionnaire, with 288 valid responses, and eight hypotheses were confirmed using Structural Equation Modeling (SEM). The findings confirm that health concerns, environmental and sustainability concerns, novelty, and subjective norms positively influence attitudes toward NAP products. In contrast, price negatively affects attitudes and WTT. Subjective norms and positive attitudes significantly enhance the WTT toward NAP products. Notably, health concerns emerged as the most influential factor affecting attitudes, while subjective norms were the strongest predictor of WTT. These results underscore the importance of addressing health benefits, environmental sustainability, and social influences while mitigating price barriers to promote the adoption of NAP products in Vietnam. The insights provided by this study can support food companies in this field to develop new products and policymakers in developing strategies to enhance consumer acceptance and drive the transition toward sustainable dietary practices. Minh Quan Nguyen Thi Thao Nguyen Tien Cuong Nguyen Hong Son Vu Thu Hien Luong Thi Hue Nguyen Copyright (c) 2025 35 5 069 077 10.51316/jst.186.etsd.2025.35.5.9 https://jst.vn/index.php/etsd/article/view/1136 In recent years, gamification has gained substantial attention in the field of education for its ability to make the learning process more engaging, foster interest, and enhance learner motivation. While its pedagogical potential has been widely acknowledged, a systematic understanding of research developments in this area remains limited. The study provides a bibliometric overview of gamification in education, drawing on 120 articles published between 2012 and August 2024 in the Taylor & Francis Online database. Using VOSviewer for co-occurrence mapping and network visualization, the analysis identifies prominent research themes, influential authors, journals, countries, and institutions. The results reveal uneven publication growth over the years, with a peak in 2021, and point to three dominant research directions: (1) measuring perceptions and motivation in the classroom, (2) assessing learning outcomes and learner experiences, and (3) pedagogical approaches and practical implementation of gamification. Minh Tri Do Thi Ngoc Mai Nguyen Thi Thanh Hai Pham Copyright (c) 2025 35 5 078 090 10.51316/jst.186.etsd.2025.35.5.10