VNUHCM Journal of Engineering and Technology <p><span id="result_box" class="" lang="en"><span title="Tạp chí Phát triển Khoa học và Công nghệ (PTKH&amp;CN) của Đại học Quốc gia thành phố Hồ Chí Minh (ĐHQG-HCM) được thành lập từ năm 1997, ra số đầu tiên vào tháng 1 năm 1998. Từ năm 2006 Tạp chí đã"><strong>Science and Technology Development Journal</strong> (STDJ), Vietnam National University - Ho Chi Minh City (VNU-HCM) was established in 1997. And the first issue was published in January 1998 with </span><span title="đăng ký mã số chuẩn quốc tế ISSN 1859-0128.">ISSN 1859-0128. </span><span title="Từ đó cho đến nay, Tạp chí PTKH&amp;CN đã trở thành diễn đàn khoa học quan trọng nhất của đội ngũ cán bộ nghiên cứu, giảng viên, nghiên cứu sinh của ĐHQG-HCM và cũng là diễn đàn khoa học công nghệ đáng tin cậy của">Since then, STDJ has become the most important scientific forum of scientists from VNU-HCM as well as</span><span title="nhiều nhà nghiên cứu, giảng viên các trường đại học khác tại Việt Nam."> other universities. </span><span title="Tạp chí đã trải qua 20 năm phát triển và đã trở thành nhịp cầu giao lưu khoa học, cũng như làm phong phú tài liệu tham khảo cho đội ngũ giảng viên, nghiên cứu sinh, sinh viên ĐHQG-HCM nói riêng và các Trường đại">The magazine has undergone 20 years of development and has become a bridge for scientific exchanges, as well as enriching reference materials for the faculty, doctoral students, students of VNU-HCM in particular and other universities, institutes... </span></span></p> <p><span id="result_box" class="" lang="en"><span title="học phía Nam nói chung. "><br></span><span title="Tính đến hết năm 2016 Tạp chí đã xuất bản được 276 số với 2714 bài nghiên cứu của các nhà khoa học, cán bộ trong và ngoài ĐHQG-HCM trong 5 lĩnh vực nghiên cứu: Kỹ thuật và Công nghệ, Khoa học Tự nhiên,">By the end of 2016, the journal has published 276 issues with 2714 research articles in five areas of research: Engineering and Technology, Natural Sciences, </span><span title="Khoa học Xã hội và Nhân văn, Kinh tế luật và Khoa học Quản lý, Khoa học Trái đất và Môi trường tương ứng với 5 chuyên san chuyên ngành của Tạp chí.">Social Sciences and Humanities, Economics of Law and Management Sciences, Earth Sciences and Environment corresponding to 5 specialized journals of the Journal. </span></span></p> <p><span id="result_box" class="" lang="en"><span title="Tạp chí đã được phát hành tại các thư viện của các đơn vị thành viên của ĐHQG-HCM, các Sở Khoa học Công nghệ của các tỉnh thành trên cả nước và được Hội đồng học hàm Giáo sư Nhà nước đánh giá cao.">The magazine has been widely indexed in the various libraries at Vietnam. </span></span></p> Viet Nam National University Ho Chi Minh City en-US VNUHCM Journal of Engineering and Technology 2615-9872 <p>Copyright The Author(s) 2018. This article is published with open access by Vietnam National University, Ho Chi Minh city, Vietnam. This article is distributed under the terms of the&nbsp;<a href="" target="_blank" rel="noopener">Creative Commons Attribution License (CC-BY 4.0)</a> which permits any use, distribution, and reproduction in any medium, provided the original author(s) and the source are credited.&nbsp;</p> Synthesis and evaluation of antibacterial and antifungal activities of asymmetric 2-methylimidazole-4,5-dicarboxamide derivatives containing morpholine <p>For several years, heterocycles have been attracted the interest of researchers due to their diverse biological activity, such as antibacterial, antifungal, antidengue properties,… Imidazole and morpholine are two heterocycles that have interesting application in potency, pharmacokinetics, pharmacodynamics… When combined in the same compound, they may generate new compounds with potential bioactivities. Imidazole-4,5-dicarboxamide (I45DC) compounds were synthesized using benzimidazole derivatives as starting material through four-step procedure: oxidation cleavage of 2-methylbenzimidazole, synthesis of pyrazinedione diacide dichloride, amidation of pyrazinedione diacide dichloride, and ring opening pyrazinedione by morpholine. The structures were determined by IR, MS, NMR spectra. The results showed that the derivatives have purity and structure consistent with expectations. Eight asymmetric I45DC compounds were synthesized, all of which were new based on Scifinder in December 2022. The yield of the reactions varies from 23 – 80%, in which the important reaction is the final one with the yield of 23 – 54% varying depending on the position of the substituents. The antibacterial, antifungal, antidengue activitives were screened on five bacterial and two fungi strains. However, they did not exhibit activity againtst tested bacteria and fungi. Nonetheless, the new I45DC compounds help to diversify synthetic compounds.</p> Phương Nguyễn Hoài Huỳnh Nguyen Thanh Phuc Truong Phuong Vo Thi Cam Van ##submission.copyrightStatement## 2024-01-14 2024-01-14 6 4 press press 10.32508/stdjet.v6i4.1085 title description none g Research, experiment and comparison of single axis and dual axes solar tracking to increase solar panel power capacity <p>A simulation program combined with experimental testing of three solar panel tracking systems along one axis and two dual axes will be introduced in this article. Solar panel systems are widely used today, but to achieve high performance, it is necessary to design solar panel systems that can automatically align themselves perpendicularly to the incident radiation to optimize their efficiency. Therefore, the application of solar panel tracking systems not only increases the generated electrical power but also helps improve the current state of depletion of fossil fuel resources. Based on actual measurement results and simulated data, the article demonstrates that the electrical power output of solar panels increases by 3.96% when a dual-axis tracking system is applied compared to a one-axis tracking system, and it increases by 36.8% compared to a fixed 15° tilt-angle panel, a common angle in Vietnam. Furthermore, based on the geometric angle relationships between the Sun and the inclined plane, the research team also applied a simulation program to investigate the different efficiencies of continuous tracking models throughout a year in Ho Chi Minh City, Vietnam. The results show that in August, when the Sun is at its highest position, the efficiency difference between the two models is not significant, at 3.4%. However, when the Sun is in a lower position in January, the efficiency difference is more pronounced, with the two-axis tracking system being 45.9% more efficient than the one-axis system.</p> Khanh Quoc Ngo Khang Trong Hoang Nghi Tat Han Bao The Nguyen ##submission.copyrightStatement## 2023-12-31 2023-12-31 6 4 2035 2047 10.32508/stdjet.v6i4.1285 title description none g