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Journal of Environmental Protection 2022年第11期13卷 870-880页

作者： Vo Thi anh Tran Khanh Minh ha lan anh Mai Dinh Kien Vu Hoai Dang Duc Nhan Institute for Nuclear Science and Technology Hanoi Vietnam

The δ18O and δ2H stable isotope techniques for studying properties of groundwater and surface help us to understand more clearly about the distribution and movement of groundwater in the South of hanoi area. There were 68 water samples from the studying area and analyzed by a Liquid Water Isotope Analyzer (LWIA-24D). The stable isotope values of the groundwater from Pleistocene aquifers were range from -3.21‰ to -9.55‰ δ18O and -35.32‰ to -67.44‰ δ2H;rainwater from -8.18‰ to -4.13‰ δ18O and -61.19‰ to -17.93‰ δ2H;Red river water from -7.51‰ to -5.29‰ δ18O and -51.60‰ to -38.99‰ δ2H. Based on stable isotope characteristics, the results show that there was a relationship between surface water and groundwater in the South of hanoi city. It is that groundwater recharges for river water in the dry season with 74%, and in the rainfall season groundwater is recharged from river with 87%.

关键词： Stable Isotopes Groundwater Surface Water River Water Precipitation Recharge

Using Isotope Technology for Surface Water Environment Research in Southern hanoi

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Journal of Environmental Protection 2016年第8期7卷 1113-1118页

作者： Vo Thi anh Tran Khanh Minh Trinh Van Giap ha lan anh Nguyen Thanh Cong Nguyen Hong Thinh Vu Hoai Institute for Nuclear Science and Technology Hanoi Vietnam Vinh University Vinh Vietnam

The surface water in the southern of hanoi capital is researched by identifying δ2H and δ18O stable isotopes together with EC, DO, BOD5, COD, TSS. Surface water samples for studying include the Red river, Nhue river and Kim Nguu river, Thanh Nhan lake, Yen So lake and Van Quan lake were collected in the dry season (April) and the rainy season (August) in 2015. The stable isotope analysis results showed that the δ18O values is a range from -42.53‰ to -64.05‰ and, the δ2H values is the range from -5.09‰ to -8.79‰ under global meteoric waterline (in the water vapor region). The δ2H results of the rivers and lakes in the dry season are more negative than the rainy season with a small difference. The δ18O results of lakes in the dry season are more negative than the rainy season, but the δ18O results of river in the dry season are more positive than the rainy season. The results of the EC, BOD, COD, DO, TSS analysis showed that surface water environment has changed clearly in the two seasons and the contamination level in the dry season is usually higher than the rainy season. The lakes and rivers strongly influenced by human activities led to seriously pollution are Van Quan lake and Yen So lake, Nhue river and Kim Nguu river.

关键词： Isotope Technology Surface Water Quality Change in Difference Seasons

Study the Changes in Soil Organic Carbon of Rice-Maize Cropping System in the Top Layer of Alluvisol Soil in Dan Phuong: A Study of C-13 Stable Isotope Composition (<i>δ</i><sup>13</sup>C)

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Journal of Environmental Protection 2019年第10期10卷 1361-1372页

作者： Nguyen Thi Hong Thinh Vu Hoai ha lan anh Vo Thi anh Truong Viet Chau Trinh Van Giap Tran Minh Tien Isotope Hydrology Laboratory Institute for Nuclear Science and TechnologyHanoiVietnam Soils and Fertilizers Research Institute HanoiVietnam

In this study, the experiments on field were conducted to examine the change in the content of soil organic carbon (SOC), its C-13 stable isotope composition (δ 13C) and some main physical, chemical parameters (soil moisture, pH, soil density, content of humic, fulvic, total N, total P, total K) in alluvial soil of Dan Phuong region—Vietnam at a depth of 0 - 30 cm when we changed the regime from 2 maize -1 rice crop to 2 rice - 1 maize crop per 1 year. In addition to analyzing the main parameters in soil, C content and its δ 13C value in parts of rice and maize (root, stem and leaf) were also analyzed to assess the contribution of plant residues on soil organic carbon content after harvest. The experiment was carried out in 2016-2017 on the field with the traditional farming method of local farmers along with the tropical monsoon weather conditions of the North-Vietnam. The results showed that SOC had positive correlation with total N, total P parameters and negative correlation with δ 13C values of soil samples at two layers (0 - 15 cm and 15 - 30 cm). The average of total dry biomass (stem, stump + roots and leaf parts) per 1 rice and 1 maize crop was 10.64 Mg/ha and 9.09 Mg/ha, respectively. The average of δ 13C value of rice (C3 plant) was -29.78‰ and its value of maize (C4 plant) was -12.61‰. The new plant (rice) contributes to the total soil organic carbon content from 11.31% to 44.14% at the 0 - 15 cm layer and from 6.55% to 11.31% at the 15 - 30 cm layer in one-year experiment period.

关键词： Soil Organic Carbon (SOC) C-13 Stable Isotope Maize and Rice Crop Soil Properties

BTEX pollution caused by motorcycles in the megacity of HoChiMinh

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Journal of Environmental Sciences 2013年第2期25卷 348-356页

作者： Tran Thi Ngoc lan Pham anh Minh University of Science Vietnam National University227 Nguyen Van CuHoChiMinh 70000Vietnam

Monitoring of benzene, toluene and xylenes （BTEX） was conducted along with traffic counts at 17 roadside sites in urban areas of HoChiMinh. Toluene was the most abundant substance, followed by p,m-xylenes, benzene, o-xylene and ethylbenzene. The maximum observed hour-average benzene concentration was 254 μg/m3 . Motorcycles contributed to 91% of the traffic fleet. High correlations among BTEX species, between BTEX concentrations and the volume of on-road motorcycles, and between inter-species ratios in air and in gasoline indicate the motorcycle-exhaust origin of BTEX species. Daily concentrations of benzene, toluene, ethylbenzene, p,m-xylenes and o-xylene were 56, 121, 21, 64 and 23 μg/m 3 , respectively. p,m-xylenes possess the highest ozone formation potential among the BTEX family.

关键词： air pollution benzene BTEX HoChiMinh motorcycle exhaust

landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 467-500页

作者： landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models Duc-Dam Nguyen Nguyen Viet Tiep Quynh-anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham Faculty of Civil Engineering University of Transport TechnologyThanh XuanHa Noi100000Vietnam Faculty of Hydraulic Engineering Hanoi University of Civil EngineeringHa Noi100000Vietnam DDG(R)Geological Survey of India Gandhinagar382010India Research Institute of the University of Bucharest Bucharest050663Romania National Institute of Hydrology and Water Management Bucharest013686Romania Department of Civil Engineering Transilvania University of BrasovBrasov500152Romania Danube Delta National Institute for Research and Development Tulcea820112Romania Marwadi University Research Center(MURC) Marwadi UniversityRajkotGujaratBharat360003India Department of Civil Engineering Faculty of Engineering&TechnologyMarwadi UniversityRajkotGujaratBharat360003India

This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and ***,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and *** models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to *** factors were instrumental in predicting the output variable,which was the probability of landslide *** analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other *** AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of *** results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making.

关键词： landslide susceptibility map spatial analysis ensemble modelling information values(IV)

Transparent conducting materials discovery using high-throughput computing

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npj Computational Materials 2019年第1期5卷 606-618页

作者： Guillaume Brunin Francesco Ricci Viet-anh ha Gian-Marco Rignanese Geoffroy hautier UCLouvain Institut de la Matière Condensée et des Nanosciences(IMCN)Chemin desÉtoiles 8Louvain-la-Neuve 1348Belgium

Transparent conducting materials(TCMs)are required in many applications from solar cells to transparent *** high performance materials combining the antagonistic properties of transparency and conductivity has been challenging especially for p-type ***,high-throughput ab initio computational screening has emerged as a formidable tool for accelerating materials *** this review,we discuss how this approach has been applied for identifying *** provide a brief overview of the different materials properties of importance for TCMs(e.g.,dopability,effective mass,and transparency)and present the ab initio techniques available to assess *** focus on the accuracy of the methodologies as well as their suitability for high-throughput ***,we review the different high-throughput computational studies searching for new TCMs and discuss their differences in terms of methodologies and main findings.

关键词： transparency conducting suitability

Studies on sustainable features of vernacular architecture in different regions across the world:A comprehensive synthesis and evaluation

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Frontiers of Architectural Research 2019年第4期8卷 535-548页

作者： anh Tuan Nguyen Nguyen Song ha Truong David Rockwood anh Dung Tran Le Faculty of Architecture the University of Danang-University of Science and TechnologyDa NangViet Nam School of Architecture University of Hawaii at ManoaUSA Laborotoire des Technologies Innovantes(LTI) Universite de Picardie Jules VerneFrance

Due to the increasing pressure brought by recent global environmental problems,building designers are embracing regionalism and the knowledge of traditional structures,arguing that these structures are energy efficient and highly *** observe clear evidence of the increasing interest in vernacular architecture among the research *** study therefore aims to clarify the contents and issues raised in the studies on vernacular architecture and the knowledge and recommendations that can be derived from them.A database of the research is established by collecting many studies from primary *** data is carefully refined and categorized into a table where synthesized information is *** results of this study show an uneven geographic and climatic distribution of the studies;the trend in selecting research objectives and research objects;the choice of research methods with a clear shift towards quantitative research methods,and the generic findings from the database of the *** results can support diverse inquiries about vernacular architecture across the world and be used as a resource or an orientation to support numerous subsequent studies.

关键词： Vernacular architecture Traditional architecture Sustainable feature Research method Building design

LiMn_2O_4/CNTs and LiNi_(0.5)Mn_(1.5)O_4/CNTs Nanocomposites as High-Performance Cathode Materials for Lithium-Ion Batteries

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Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 122-128页

作者： Thang Van Le ha Tran Nguyen anh Tuan Luu Man Van Tran Phung Loan My Le Faculty of Materials Technology Ho Chi Minh University of Technology 268 Ly Thuong Kiet Ward 14 District 10 Ho Chi Minh City Vietnam Department of Physical Chemistry University of Science VNUHCM 227 Nguyen Van Cu Street District 5 Ho Chi Minh CityVietnam

The demand of higher energy density and higher power capacity of lithium（Li）-ion secondary batteries has led to the search for electrode materials whose capacities and performance are better than those available today. Carbon nanotubes（CNTs）, with their unique properties such as 1D tubular structure, high electrical and thermal conductivities, and extremely large surface area, have been used as materials to prepare cathodes for Li-ion batteries. The structure and morphology of CNTs were analyzed by X-ray diffraction（XRD）, scanning electron microscopy（SEM）, and transmission electron microscopy（TEM）. The functional groups on the purified CNT surface such as –COOH, –OH were characterized by Fourier Transform infrared spectroscopy. The electrode materials were fabricated from LiMn2O4（LMO）, doped spinel LiNi0.5Mn1.5O4, and purified CNTs via solid-state reaction. The structure and morphology of the electrode were characterized using XRD, SEM, and TEM. Finally, the efficiency of the electrode materials using CNTs was evaluated by cyclic voltammetry and electrochemical impedance spectroscopy.

关键词： Nanocomposites Carbon nanotubes(CNTs) Spinel materials Lithium-ion batteries(LIBs)

*** human visual cortex responses to flickering light using functional near infrared spectroscopy and constrained ICA

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Journal of Innovative Optical Health Sciences 2014年第6期7卷 77-89页

作者： Nguyen Duc Thang Vo Van Toi Le Giang Tran Nguyen Huynh Minh Tam lan anh Trinh Biomedical Engineering Department International University Vietnam National Universities HCMCVietnam University of Saskatchewan Canada Electronics Engineering Department Posts and Telecommunications Institute of Technology Ho Chi Minh City Vietnam

The human visual sensitivity to the flickering light has been under investigation for *** finding of research in this area can contribute to the understanding of human visual system mechanism and visual disorders,and establishing diagnosis and treatment of *** aim of this study is to investigate the ffects of the flickering light to the visual cortex by monitoring the hemodynamic responses of the brain with the functional near infrared spectrosoopy(ENIRS)*** the acquired fNIRS signals are afected by physiological factors and measurement artifacts,constrained independent component analysis(eICA)was applied to extract the actual fNIRS responses from the obtained *** experimental results revealed significant changes(phat there was a slight decrease of the oxygenated hemoglobin con-centration(about 5.69%)over four frequencies when the modulation ***,the variations of oxy and deoxy-hemoglobin were not statistically significant.

关键词： Papillometre visual stimulation functional near infrared spectroscopy constrained independent component analysis

Antidiabetic and antioxidant activities of red seaweed Laurencia dendroidea

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Asian Pacific Journal of Tropical Biomedicine 2019年第12期9卷 501-509页

作者： The han Nguyen Thi Huyen Nguyen Van Minh Nguyen Thi lan Phuong Nguyen Thi Van anh Tran anh Duy Do Sang Moo Kim Faculty of Food Technology Nha Trang University02 Nguyen Dinh Chieu StreetNha Trang CityKhanh HoaVietnam Quality Control Department Institute of Vaccines and Medical BiologicalsNha Trang CityKhanh HoaVietnam Faculty of Pharmacy University of Medicine and Pharmacy of Ho Chi Minh City41 Dinh Tien Hoang StreetHo Chi Minh CityVietnam Research Department of Marine Conservation Research Institute for Marine Fisheries224 Le Lai StreetHai Phong CityVietnam Department of Marine Food Science and Technology Gangneung-Wonju National University7 Jukheon-gilGangneung 25457Republic of Korea

Objective:To investigate antidiabetic and antioxidant activities of the extract and fractions from Vietnamese red seaweed Laurencia ***:The seaweed Laurencia dendroidea was extracted by using microwave-assisted extraction method in 80%*** seaweed extract was then fractionated using different solvents(n-hexane,chloroform,ethyl acetate,butanol and water).These obtained fractions were evaluated forα-glucosidase inhibitory and antioxidant *** activities were tested using DPPH,nitric oxide radical scavenging and metal chelating *** enzyme inhibition mode was determined using Lineweaver-Burk *** acidic and thermal stabilities,the ethyl acetate fraction was treated at pH 2.0 and 100℃,*** residual inhibitory activity of the fraction was calculated based on the initial inhibitory *** in vivo antidiabetic activity,mice were divided into four groups,including normal control,diabetic control,diabetic mice treated with ethyl acetate fraction and diabetic mice treated with *** glucose level of treated mice during acute and prolonged treatments was *** evaluate the toxicity of the ethyl acetate fraction,the body weight changes and activities of liver function enzymes(aspartate transaminase,alanine transaminase and gammaglutamyl transferase)were carried ***:The extract of Laurencia dendroidea showed strongα-glucosidase inhibitory and DPPH radical scavenging *** concentrations affected bothα-glucosidase inhibitory and antioxidant activities.A 80%aqueous methanol was the suitable solvent for extraction of enzyme inhibitors and *** solvent fractions,ethyl acetate fraction had the highest inhibitory activities againstα-glucosidase with a mixed type of inhibition and the strongest antioxidant activities,and was stable under acidic and thermal *** ethyl acetate fraction treated diabetic mice significantly reduced blood glucose level compare

关键词： α-Glucosidase inhibitor Antidiabetic Antioxidant Red seaweeds Vietnam