Ministry of Science and Technology, Vietnam最新文献

Prediction of thermodynamic properties oflanthanide/transition metal alloys by deep learning 通过深度学习预测镧系元素/过渡金属合金的热力学性质

Ministry of Science and Technology, Vietnam Pub Date : 2024-07-16 DOI: 10.31276/vjst.2024.0006

Tien Lam Pham, Tien-Cuong Nguyen, Van Quyen Nguyen

引用次数: 0

Study on the effect of freezing pretreatment and endogenous fermentation on the quality and processing time of black shallots using moist heat treatment method 利用湿热处理法研究冷冻预处理和内源发酵对黑香葱品质和加工时间的影响

Ministry of Science and Technology, Vietnam Pub Date : 2024-07-03 DOI: 10.31276/vjst.2024.0005

Phuong Chi Tran, Thi Le Hang Hoang, Dinh Thang Tran

{"title":"Study on the effect of freezing pretreatment and endogenous fermentation on the quality and processing time of black shallots using moist heat treatment method","authors":"Phuong Chi Tran, Thi Le Hang Hoang, Dinh Thang Tran","doi":"10.31276/vjst.2024.0005","DOIUrl":"https://doi.org/10.31276/vjst.2024.0005","url":null,"abstract":"Black shallots are new products made by processing fresh shallots (Allium ascolanicumL.) under controlled temperature and humidity conditions without the use of additives. The purpose of this study was to determine suitable freezing pretreatment and endogenous fermentation conditions (treatment temperature, treatment time) to break down the cell structure in raw materials, to promote reactions caused by enzyme (hydrolysis reaction of polysaccharides, proteins, reaction of converting polyphenol compounds in bound form to free form...), improving the content of nutritional ingredients and active ingredients in black shallotproducts and shorten fermentation time. The results have determined that the suitable freezing pretreatment condition at a temperature of -20oC for 30 hours and the suitable endogenous fermentation condition at a temperature of 45oC for 2 days. Under these conditions, the black shallotproducts achieved good quality, corresponding to the total fermentation time shortened to 17 days compared to the control which was 24 days. This research initially gave feasibility for black shallotproduction on an industrial scale.","PeriodicalId":506424,"journal":{"name":"Ministry of Science and Technology, Vietnam","volume":"136 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141681836","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comprehensive analysis of cement-stabilised dredged marine soil: Evaluating physical, microstructural, and mechanical characteristics 全面分析水泥稳定疏浚海洋土壤：评估物理、微观结构和机械特性

Ministry of Science and Technology, Vietnam Pub Date : 2024-06-15 DOI: 10.31276/vjste.66(2).52-60

Bhim Kumar Dahal, Jun Jie Zheng

{"title":"Comprehensive analysis of cement-stabilised dredged marine soil: Evaluating physical, microstructural, and mechanical characteristics","authors":"Bhim Kumar Dahal, Jun Jie Zheng","doi":"10.31276/vjste.66(2).52-60","DOIUrl":"https://doi.org/10.31276/vjste.66(2).52-60","url":null,"abstract":"This study evaluates the index, microstructural, and mechanical behaviour of cement-stabilised soft soil. The marine soil dredged from Hangzhou is taken for the study. Different percentages of ordinary Portland cement (OPC)by dry mass were added to the soils during reconstitution, i.e., 5, 10, 15, and 20%. The reconstituted samples were analysed in the laboratory to determine basic properties such as moisture content, void ratio, density, specific gravity, consistency limits, and particle size distribution. The microstructures of the reconstituted samples were also evaluated through scanning electron microscopy. Results inferred a significant impact on the physical properties of the soil. An increase in cement content increases the consistency limits. Additionally, the specific gravity, plasticity index, and density of the treated soil initially decreased but increased upon further addition of cement content. The microstructure of the soil transformed from a dispersed to a flocculated structure, with larger and denser particles. The change in microstructure was also evident in the particle size distribution, with an increase in cement content leading to larger size particles. Finally, the unconfined compression test conducted on the reconstituted soil indicates a substantial enhancement in strength with higher cement content and prolonged curing periods.","PeriodicalId":506424,"journal":{"name":"Ministry of Science and Technology, Vietnam","volume":"93 4","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141337437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stochastic modelling of material variability in structural dynamics: A threefold comparison of Monte Carlo, polynomial chaos, and random sampling techniques 结构动力学中材料可变性的随机建模：蒙特卡罗、多项式混沌和随机抽样技术的三重比较

Ministry of Science and Technology, Vietnam Pub Date : 2024-06-15 DOI: 10.31276/vjste.66(2).33-51

Rakesh Kumar

{"title":"Stochastic modelling of material variability in structural dynamics: A threefold comparison of Monte Carlo, polynomial chaos, and random sampling techniques","authors":"Rakesh Kumar","doi":"10.31276/vjste.66(2).33-51","DOIUrl":"https://doi.org/10.31276/vjste.66(2).33-51","url":null,"abstract":"This article investigates the influence of random elastic modulus on beam eigenfrequencies using multiple simulation techniques: Monte Carlo simulations (employing Cholesky decomposition (MCS-CD) and Kosambi-Karhunen-Loève expansion (MCS-KKL)), Polynomial Chaos expansion (PCE), and a proposed Random Sampling method (RSM). Anomalies in Monte Carlo simulations, where normally distributed elastic modulus led to negative values and imaginary eigenfrequencies, were effectively addressed by adopting a log-normal distribution. Comparative analyses focused on covariance variation of the first three eigenfrequencies with correlation length and standard deviation of the random field, highlighting nuanced differences between normal and log-normal distributions. PCE exhibited distinct responses, showcasing variations in covariance with different distributions. The study culminates in eigenfrequency estimation using the proposed RSM, wherein the beam is discretised into n elements with randomly assigned elastic moduli. The mean and variance of eigenfrequencies are compared with existing methods, which represent an alternative method for achieving similar outcomes.These comparative studies provide a comprehensive understanding of how different statistical treatments and simulation methods impact the reliability and accuracy of eigenfrequency predictions in beams with random elastic properties, thus contributing valuable insights for structural analysis and design under uncertainty.","PeriodicalId":506424,"journal":{"name":"Ministry of Science and Technology, Vietnam","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141337317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

GPR investigation of the cause of persistent failure of a university road 对一条大学路持续塌方原因的 GPR 勘察

Ministry of Science and Technology, Vietnam Pub Date : 2024-06-15 DOI: 10.31276/vjste.66(2).114-120

Muslim Babatunde Aminu, Femi Ologunaye

{"title":"GPR investigation of the cause of persistent failure of a university road","authors":"Muslim Babatunde Aminu, Femi Ologunaye","doi":"10.31276/vjste.66(2).114-120","DOIUrl":"https://doi.org/10.31276/vjste.66(2).114-120","url":null,"abstract":"We present the results of a multi-frequency ground-penetrating radar (GPR) survey over a university road in south-western Nigeria that has experienced persistent failures. The goal was to evaluate causes of failure to aid remediation efforts. Data was collected concurrently at 250, 500, and 1000 MHz using a UTSI electronic trivue system. Data were processed and interpreted using Reflex-Win. Visual observations of major features apparent on the road surface including failed sections were noted. Imaged features included possible bases of the surface course, base course and sub-base, subsurface projections of an outcropping and buried basement rocks, three deeply cut and back-filled sections that lie beneath sections of the road that have experienced persistent failure, and the ringing effects and rebar-associated reflection hyperbolae of two reinforced concrete drains. Indications of preferential wetting of the shallow subsurface beneath much of the failed sections suggest that failure is due to excessive moisture content in these sections. These failed sections generally correspond to regions of deep cut and backfill, and regions cut and filled for the construction of reinforced concrete drains. Apparently, the backfills at these locations have failed to prevent water influx into the subsurface and more effective remediation measures need to be deployed.","PeriodicalId":506424,"journal":{"name":"Ministry of Science and Technology, Vietnam","volume":"8 11","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141337205","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Convective heat transfer by nanofluid jet impingement cooling on automobile radiator with nozzle plate spacing 汽车散热器上纳米流体射流撞击冷却的对流传热（喷嘴板间距

Ministry of Science and Technology, Vietnam Pub Date : 2024-06-15 DOI: 10.31276/vjste.66(2).10-18

M. Peeraiah, K. N. Rao, B. Balakrishna

引用次数: 0

Chemical constituents, antioxidant and antifungal activities of the essential oil from Vietnamese Ocimum tenuiflorum L.leaves 越南天竺葵叶精油的化学成分、抗氧化和抗真菌活性

Ministry of Science and Technology, Vietnam Pub Date : 2024-06-15 DOI: 10.31276/vjste.66(2).69-75

Thi-Hoan Luong, Huu-Khanh-Tan Tran, Woo-Jin Jung, Van-Viet Nguyen, Dang-Minh-Chanh Nguyen

{"title":"Chemical constituents, antioxidant and antifungal activities of the essential oil from Vietnamese Ocimum tenuiflorum L.leaves","authors":"Thi-Hoan Luong, Huu-Khanh-Tan Tran, Woo-Jin Jung, Van-Viet Nguyen, Dang-Minh-Chanh Nguyen","doi":"10.31276/vjste.66(2).69-75","DOIUrl":"https://doi.org/10.31276/vjste.66(2).69-75","url":null,"abstract":"In this study, the authors aim to determine the chemical compositions of the essential oil from Ocimum tenuiflorumleaves and to evaluate its antioxidant and antifungal activities. The essential oil used in this research, extracted by hydrodistillation, was chemically profiled using gas chromatography/mass spectrometry (GC/MS) analysis. Methyl eugenol (46.07%), caryophyllene (15.65%), eugenol (11.83%), β-elemene (4.33%), β-copaene (4.18%), caryophyllene oxide (3.18%), and α-copaene (1.95%) were identified as major components of the essential oil. The results indicated that the essential oil of O. tenuiflorum leaves possessed relatively high 2,2-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging activities with IC50 values of 53.5 and 55.1 μg/ml, respectively, compared with 67.2 and 63.2 μg/ml, respectively, for the positive control. The reducing powers of O. tenuiflorum essential oil and butylated hydroxytoluene (BHT) at a concentration of 200 μg/ml were 0.95 and 0.73, respectively. Additionally, the essential oil of O. tenuiflorum at a concentration of 200 μg/ml strongly inhibited the mycelial growth of Rhizoctonia solani.","PeriodicalId":506424,"journal":{"name":"Ministry of Science and Technology, Vietnam","volume":"2 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141336502","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Physico-chemical analysis in ternary organic mixtures at various temperatures with an acoustical approach 用声学方法对不同温度下的三元有机混合物进行物理化学分析

Ministry of Science and Technology, Vietnam Pub Date : 2024-06-15 DOI: 10.31276/vjste.66(2).03-09

S. Nithiyanantham, V. Vanathi, S. Mullainathan, S. Mahalakshmi, L. Palaniappan

{"title":"Physico-chemical analysis in ternary organic mixtures at various temperatures with an acoustical approach","authors":"S. Nithiyanantham, V. Vanathi, S. Mullainathan, S. Mahalakshmi, L. Palaniappan","doi":"10.31276/vjste.66(2).03-09","DOIUrl":"https://doi.org/10.31276/vjste.66(2).03-09","url":null,"abstract":"Thermo-dynamical analyses of organic mixtures are essential across industries. Ultrasonic sound velocity (U) measurements in the ternary organic mixtures of Toluene, Chloroform, and Cyclohexane have been conducted between 303.15, 308.15 and 313.15 K. The experimental/derived data were utilised to compute deviations for their excess values such as adiabatic compressibility (βE), free length (LfE), free volume (VfE), impedance (ZE), internal pressure (πiE) and enthalpy (HE) to investigate and confirm the types of interactions. Using these derived parameters, excess parameters were calculated to further reaffirm the type, strength, magnitude, and potential interactions such as complex formation, dipole-dipole, and dispersive types. Moreover, both ideal and non-ideal behaviours were analysed. The ultrasonic velocity data were validated against some contemporary and well-known models like Namoto’s relation (NR), Ideal mixture relation (IMR), Impedance dependence relation (IDR), Collision factor theory (CFT) and Nutch-Kunkies (NK) theorem. From the IMR and IDR are gives well approach to experimental one. And a comparative study of these models was conducted to ascertain the possible types of interactions within the mixtures through their molecular interaction parameter, percentage deviation, standard percentage error deviation.","PeriodicalId":506424,"journal":{"name":"Ministry of Science and Technology, Vietnam","volume":"81 16","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141338095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparing the efficacy of online vs. offline methods in modulating emotional responses through mental stress tasks 比较在线和离线方法在通过心理压力任务调节情绪反应方面的功效

Ministry of Science and Technology, Vietnam Pub Date : 2024-06-15 DOI: 10.31276/vjste.66(2).107-113

Luan Van Tran, Anh Phuc Hoang Le, Thao Mai Le, My Thi Tra Nguyen, Quang Lam Nguyen, Huong Thi Thanh Ha

{"title":"Comparing the efficacy of online vs. offline methods in modulating emotional responses through mental stress tasks","authors":"Luan Van Tran, Anh Phuc Hoang Le, Thao Mai Le, My Thi Tra Nguyen, Quang Lam Nguyen, Huong Thi Thanh Ha","doi":"10.31276/vjste.66(2).107-113","DOIUrl":"https://doi.org/10.31276/vjste.66(2).107-113","url":null,"abstract":"Emotion regulation and stress represent two complex, intertwined processes. Yet, there is a paucity of studies examining the effect of stress on emotional regulation among Vietnamese students, specifically the influence of online and offline experimental conditions. This study investigates these dynamics by subjective assessment of the emotional responses of the subjects participating in this study. The research was structured in three primary phases: preliminary, online (conducted via the Internet), and offline (conducted in person) experiments. The preliminary phase (N=16) aimed to validate the appropriateness of the International Affective Picture System (IAPS) picture library and emotional stimulation videos from previous studies. Participants in the online (N=30) and offline (N=45) experiments were divided into control and stress groups, distinguished by the difficulty and urgency of the mental arithmetic task (MAT). Participants were then asked to view photos and videos and to rate their subjective feelings using the Self-assessment Manikin (SAM). The online experimental session revealed that subjects under acute stress exhibited heightened sensitivity, as indicated by increased valence scores in the positive and neutral groups, and decreased scores for negative imagery (Positive: MD=0.292, p=0.0113; Neutral: MD=0.245, p=0.001; Negative: MD=-0.435, p<0.0001). An increase in arousal scores in the stress group was also observed for positive (p<0.0001) and neutral sets (p<0.0001). However, these findings were not replicated in the offline experiment session. In conclusion, the IAPS pictures have proven suitable for emotional studies among Vietnamese students.","PeriodicalId":506424,"journal":{"name":"Ministry of Science and Technology, Vietnam","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141337029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Molecular docking and molecular dynamics simulation revealed potential compounds in Salvia miltiorrhiza for inhibiting enzymes and receptors in Alzheimer’s disease 分子对接和分子动力学模拟揭示了丹参中抑制阿尔茨海默病酶和受体的潜在化合物

Ministry of Science and Technology, Vietnam Pub Date : 2024-06-15 DOI: 10.31276/vjste.66(2).89-100

Tung Bui Thanh, Trang Vu Dai, Huong Le Thi

{"title":"Molecular docking and molecular dynamics simulation revealed potential compounds in Salvia miltiorrhiza for inhibiting enzymes and receptors in Alzheimer’s disease","authors":"Tung Bui Thanh, Trang Vu Dai, Huong Le Thi","doi":"10.31276/vjste.66(2).89-100","DOIUrl":"https://doi.org/10.31276/vjste.66(2).89-100","url":null,"abstract":"Alzheimer’s disease is an age-related neurodegenerative disorder that leads to cognitive and functional decline. Potential target proteins for managing Alzheimer’s disease include Acetylcholinesterase (AChE), Butyrylcholinesterase (BuChE), Beta-secretase cleavage enzyme (BACE1) and N-methyl-D-aspartate (NMDA) receptors. In this study, we conducted in silico evaluations of the inhibitory effects of Salvia miltiorrhiza’s compounds on AChE, BuChE, BACE1, and NMDA receptors. The Lipinski's rule of five was employed to compare phytochemicals with drug-like and non-drug-like properties. Based on previous publications, we compiled a list of 30 compounds from S.miltiorrhiza with potential for improving Alzheimer’s disease. Among these 30 compounds, six natural compounds exhibited potential inhibition of all four target proteins. Five of these six compounds, namely Tanshinone I, Tanshinone IIA, Isotanshinone I, Dihydroisotanshinone I, and Dihydroisotanshinone II, possessed drug-like properties, good absorption potential, and the ability to cross the blood-brain barrier. In conclusion, these five compounds show the highest potential as future drug candidates for the treatment of Alzheimer’s disease.","PeriodicalId":506424,"journal":{"name":"Ministry of Science and Technology, Vietnam","volume":"10 9","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141337272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0