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Defence Technology（防务技术） 2023年第12期30卷 126-140页

作者： Ngoc-Tu Do quoc-Hoa Pham Faculty of Mechanical Engineering Hanoi University of IndustryHanoiViet Nam Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh CityViet Nam

This paper uses isogeometric analysis(IGA)based on higher-order shear deformation theory(HSDT)to study the dynamic response of bio-inspired helicoid laminated composite(B-iHLC)plates resting on Pasternak foundation(PF)excited by explosive *** takes advantage of non-uniform rational Bspline(NURBS)basic functions to exactly represent the structure geometry models and the attainment of higher-order approximation *** method also ensures a C1 continuous function in the analysis of transverse shear deformation via ***,IGA eliminates the requirement for correction factors and delivers accurate *** foundation with two stiffness parameters:springer stiffness(k_(1))and shear stiffness(k_(2)).The derivation of the governing equations is based on Hamilton's *** proposed method is validated through numerical examples.A comprehensive analysis of the impact of geometrical parameters,material properties,boundary conditions(BCs),and foundation stiffness on dynamic response of B-i HLC plates is carried out.

关键词： Isogeometric analysis Pasternak foundation Dynamic response Laminated composite

Organic bases as additives for steam-assisted gravity drainage

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Petroleum Science 2019年第6期16卷 1332-1343页

作者： Sean D.Brame Litan Li Biplab Mukherjee Pramod D.Patil Stephanie Potisek quoc P.nguyen Petroleum and Geosystems Engineering Department The University of Texas at Austin200 E.Dean KeetonAustinTX 78712USA The Dow Chemical Company 230 Abner Jackson PkwyECB 2A183Lake JacksonTX 77566USA

Steam-assisted gravity drainage(SAGD)is a mature technology for bitumen recovery from oil ***,it is an energy-intensive process that requires large amounts of steam to heat and mobilize *** purpose of this work is to develop ways to enhance SAGD performance through the use of organic base *** research is approached from three focus areas that supplement and guide each other:characterization tests,sand-pack floods,and computational simulation.A number of key mechanisms for enhancing oil recovery were identified,high-temperature additive characterization tests were developed,and promising alkalis were tested in porous *** was employed to history-match sandpack flood production data,in order to demonstrate the effect of an additive on the oil–water relative *** on these results,it was concluded that oxygenated organic bases had the most potential for improving bitumen recovery through reducing the oil–water interfacial tension(IFT)by increasing the pH of the *** organic bases favorably modify the interfacial energies between the immiscible oil–water phases and enable them to flow easily through the porous media during ***-pack flood tests have successfully demonstrated a 10%–15%improvement in bitumen recovery,over baseline,in the presence of IFT-reducing *** results further showed that an IFT reduction had a positive impact on SAGD *** work demonstrates the potential of organic bases to improve not only SAGD,but other steam injection ***,a number of experimental methods were developed,tried,and tested during the course of this work.

关键词： Heavy oil Steam flood Low interfacial tension Wettability Enhanced oil recovery Organic bases

Optimal Design of Bobbinless Rotary Magnetorheological Material Based Brake

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Journal of Iron and Steel Research International 2012年第S1期19卷 495-500页

作者： nguyen quoc-hung CHOI Seung-bok SONG Byung-keun Department of Mechanical Engineering Inha UniversityIncheon 402-751Korea Department of Mechanical System Engineering University of IncheonIncheon 406-840Korea

The paper presents a novel configuration in order to improve the compactness and manufacturing cost of magneto-rheological material(or fluid)based brakes(MRB in short).In conventional configurations of MRBs,the coil is normally wound on a nonmagnetic bobbin which is placed on the *** causes difficulties in manufacturing of the brake and the bottle-neck problem of magnetic *** the proposed configuration,the coil is wound directly on the inner cylinder of the *** this case,the inner cylinder of the housing should be designed in a special shape that maximizes the magnetic flux across the MR fluid(MRF)*** proposing of the new configuration of the MRBs,the modeling of the MRBs is performed based on Bingham rheological model of the *** optimal design of the proposed MRBs and conventional MRBs is then performed based on finite element analysis results of magnetic circuit of the MRBs.A comparative work between the optimal parameters of the proposed MRBs and conventional MRBs is conducted and the advanced performance characteristics of the proposed MRBs are investigated.

关键词： magneto-rheological fluid magneto-rheological brake optimal design finite element method

Marker-Assisted Selection of Xa21 Conferring Resistance to Bacterial Leaf Blight in indica Rice Cultivar LT2

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Rice science 2018年第1期25卷 52-56页

作者： Hue Thi nguyen Quang Hong VU Tan Van MAI Thu Thi nguyen Lam Duc VU Tung Thanh nguyen Long viet nguyen Hien Thu Thi VU Hue Thi NONG Trung nguyen DINH Nakano TOSHITSUGU Liet Van VU Crop Research and Development Institute Vietnam National University of Agriculture Trau Qui Gia Lam Hanoi 10000 Vietnam Faculty of Agronomy Vietnam National University of Agriculture Trau Qui Gia Lam Hanoi 10000 Vietnam Faculty of Biotechnology Vietnam National University of Agriculture Trau Qui Gia Lam Hanoi 10000 Vietnam Faculty of Land Management Vietnam National University of Agriculture Trau Qui Gia Lam Hanoi 10000 Vietnam Japan International Cooperation Agency 16 Phan Chu Trinh Hoan Kiem Hanoi 10000 Vietnam

Bacterial leaf blight of rice (BLB), caused by Xanthomonas oryzae pv. oryzae, is one of the most destructive diseases in Asian rice fields. A high-quality rice variety, LT2, was used as the recipient ***21, which carries the Xa21 gene, was used as the donor parent. The resistance gene Xa21 was introduced into LT2 by marker-assisted backcrossing. Three Xoo races were used to inoculate the improved lines following the clipping method. Eleven BC_3F_3 lines carrying Xa21 were obtained based on molecular markers and agronomic performance. The 11 lines were then inoculated with the three Xoo races. All the 11 improved lines showed better resistance to BLB than the recipient parent LT2. Based on the level of resistance to BLB and their agronomic performance, five lines (BC_3F_3 5.***.5.1, BC_3F_3 5.***.5.12, BC_3F_3 8.***.6.44, BC_3F_3 9.***.4.1 and BC_3F_3 9.***.4.23) were selected as the most promising for commercial release. These improved lines could contribute to rice production in terms of food security.

关键词： rice backcrossing bacterial leaf blight marker-assisted selection

Synthesis and characterization of core/shell structured nanophosphors CePO_4:Tb@LaPO_4 by solvothermal method

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Journal of Rare Earths 2011年第12期29卷 1147-1151页

作者： Dinh Xuan Loc Tran Thi Kim Chi Tran Thu Huong nguyen Vu Tran Kim Anh Wieslaw Strek Le quoc Minh Institute of Materials Science Vietnam Academy of Science and Technology Institute of Low Temperature and Structure Research Polish Academy of Sciences(PAN) University of Engineering and Technology

Core/shell structured CePO4：Tb（Ⅲ）@LaPO4 and CePOa：Tb（Ⅲ） were successfully synthesized in tris（2-ethylhexyl） phosphate （TEHP） and diethylene glycol （DEG） solvents for comparison of the two techniques in open air and closed reaction vessel. Morphology and crystal structure of the core/shell nanophosphors were determined by using X-ray diffraction （XRD） and transmission electron microscopy （TEM）, which showed that nanophosphors had diameter of about 5-10 nm with the monoclinic monazite phase. The nanophosphors obtained by close vessel procedure showed smaller size, more homogeneity and pure crystallite. The luminescent measurements were done upon the different excitation wavelengths in ultraviolet region and at room temperatm＇e to elucidate the influences of the used solvents and the reaction temperatures. It was found that CePO4：Tb@LaPO4 preparedby the close vessel synthesis showed the intensity of green band of the transfer from 5D4 to 7F5 energy level, which was strongly increased, and the luminescent decay time was 3.2 ms, which was longer than that of naked CePO4：Tb phosphor.

关键词： solvothermal synthesis luminescence CePOn:Tb CePOa:Tb@LaPO4 rare earths

Visualized SERS Imaging of Single Molecule by Ag/ Black Phosphorus Nanosheets

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Nano-Micro Letters 2022年第5期14卷 47-61页

作者： Chenglong Lin Shunshun Liang Yusi Peng Li Long Yanyan Li Zhengren Huang nguyen viet Long Xiaoying Luo Jianjun Liu Zhiyuan Li Yong Yang State Key Laboratory of High‑Performance Ceramics and Superfine Microstructures Shanghai Institute of CeramicsChinese Academy of Sciences1295 Dingxi RoadShanghai 200050People’s Republic of China Graduate School of the Chinese Academy of Sciences No.19(A)Yuquan RoadBeijing 100049People’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049People’s Republic of China State Key Laboratory of Oncogenes and Related Genes Shanghai Cancer InstituteRenji HospitalShanghai Jiaotong University School of Medicine200032 ShanghaiPeople’s Republic of China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510641People’s Republic of China Department of Electronics and Telecommunications Saigon UniversityHochiminh CityVietnam

Single-molecule detection and imaging are of great value in chemical analysis,biomarker identification and other trace detection ***,the localization and visualization of single molecule are still quite a ***,we report a special-engineered nanostructure of Ag nanoparticles embedded in multi-layer black phosphorus nanosheets(Ag/BP-NS)synthesized by a unique photoreduction method as a surfaceenhanced Raman scattering(SERS)*** a SERS substrate features the lowest detection limit of 10^(–20) mol L^(−1) for R6G,which is due to the three synergistic resonance enhancement of molecular resonance,photoinduced charge transfer resonance and electromagnetic *** propose a polarization-mapping strategy to realize the detection and visualization of single *** addition,combined with machine learning,Ag/BP-NS substrates are capable of recognition of different tumor exosomes,which is meaningful for monitoring and early warning of the *** work provides a reliable strategy for the detection of single molecule and a potential candidate for the practical bio-application of SERS technology.

关键词： Black phosphorus Single molecule SERS Exosome Machine learning

Seasonal Effects of Backscattering Intensity of ALOS-2 PALSAR-2 (L-Band) on Retrieval Forest Biomass in the Tropics

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Journal of Geoscience and Environment Protection 2020年第11期8卷 26-40页

作者： Luong viet nguyen Hieu Van nguyen Lap quoc Kieu Tu Trong To Thanh Kim Thi Phan Tuan Anh Pham Chi Kim Tran Space Technology Institute Vietnam Academy of Science and Technology Hanoi Vietnam Thai nguyen University of Sciences Thai Nguyen City Vietnam

This research has used the L-band radar from ALOS-2 PALSAR-2 and field work data for evaluation of seasonal effects of backscattering intensity on retrieval forest biomass in the tropics. The effects of seasonality and HH, and HV polarizations of the SAR data on the biomass were analyzed. The dry season HV polarization could explain 61% of the biomass in this study region. The dry season HV backscattering intensity was highly sensitive to the biomass compared to the rainy season backscattering intensity. The SAR data acquired in the rainy season with humid and wet canopies were not very sensitive to the in situ biomass. Strong dependence of the biomass estimates with season of SAR data acquisition confirmed that the choice of right season SAR data is very important for improving the satellite based estimates of the biomass. This research expects that the results obtained in this research will contribute to monitoring of the quantity and quality of forest biomass in vietnam and other tropical countries.

关键词： L-Band SAR ALOS-2 PALSAR-2 Backscattering Intensity Tropical Forest Biomass vietnam

Nickel composite plating with fly ash as inert particle

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Transactions of Nonferrous Metals Society of China 2013年第8期23卷 2348-2353页

作者： viet Hue nguyen Thi Anh Tuyet NGO Hong Hanh PHAM Ngoc Phong nguyen Institute of Materials Science

The Ni/FA composite plating was realized by electrodeposition with fly ash （FA） as inert particles. The main compositions of FA are 72% SiO2 and 25% A1203 in the size of 3-7 Ixm. Electrodeposition was performed in Watts bath containing FA with concentrations of 5, 20, 50 g/L, current densities of 2 and 4 A/dm2, temperature of 50 ~C and magnetic stirring of 250 r/min. Scanning electron microscope （SEM＋EDX）, electrochemical and mechanical technique were used to study morphology, composition and properties of coating. FA content in deposit is dependent on the FA concentration in solution, as well as the plating parameters. Since FA particles were incorporated in the coating, the mechanical and electrochemical properties of the coating were increased. The microhardness of Ni/FA composite plating reaches HV 430 in comparison with HV 198 of pure Ni coating. It was confirmed by electrochemical measurement that the corrosion resistance of Ni/FA composite coating was higher than that of pure Ni.

关键词： composite plating fly ash microhardness corrosion resistance inert particles

Natural variables separate the endemic areas of Clonorchis sinensis and Opisthorchis viverrini along a continuous, straight zone in Southeast Asia

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贫困所致传染病(英文) 2024年第2期13卷 1-13页

作者： Zheng Jin-Xin Zhu Hui-Hui Xia Shang Qian Men-Bao nguyen Hung Manh Sripa Banchob Sayasone Somphou Khieu Virak Bergquist Robert Zhou Xiao-Nong School of Global Health Chinese Center for Tropical Diseases Research Shanghai Jiao Tong University School of Medicine Shanghai China One Health Center Shanghai Jiao Tong University The University of Edinburgh Shanghai China National Institute of Parasitic Diseases at Chinese Center for Disease Control and Prevention (Chinese Center for Tropical Diseases Research) NHC Key Laboratory of Parasites and Vectors Biology WHO Collaborating Centre for Tropical Diseases National Center for International Research on Tropical Diseases Shanghai China Institute of Ecology and Biological Resources Graduate University of Science and Technology Vietnam Academy of Science and Technology Hoang Quoc Viet Street Hanoi Vietnam WHO Collaborating Centre for Research and Control of Opisthorchiasis (Southeast Asian Liver Fluke Disease) Tropical Disease Research Laboratory Department of Tropical Medicine Faculty of Medicine Khon Kaen University Mittraparb Road Khon Kaen Thailand Lao Tropical and Public Health Institute Ministry of Health Vientiane Lao PDR National Centre for Parasitology Entomology and Malaria Control Ministry of Health Phnom Penh Cambodia Ingerod Brastad Sweden (formerly at the UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases) World Health Organization Geneva Switzerland

Background Clonorchiasis and opisthorchiasis, caused by the liver flukesClonorchis sinensis andOpisthorchis viverrini respectively, represent significant neglected tropical diseases (NTDs) in Asia. The co-existence of these pathogens in overlapping regions complicates effective disease control strategies. This study aimed to clarify the distribution and interaction of these diseases within Southeast *** We systematically collated occurrence records of human clonorchiasis (n = 1809) and opisthorchiasis (n = 731) across the Southeast Asia countries. Utilizing species distribution models incorporating environmental and climatic data, coupled machine learning algorithms with boosted regression trees, we predicted and distinguished endemic areas for each fluke species. Machine learning techniques, including geospatial analysis, were employed to delineate the boundaries between these *** Our analysis revealed that the endemic range ofC. sinensis andO. viverrini in Southeast Asia primarily spans across part of China, vietnam, Thailand, Laos, and Cambodia. During the period from 2000 to 2018, we identifiedC. sinensis infections in 84 distinct locations, predominantly in southern China (Guangxi Zhuang Autonomous Region) and northern vietnam. In a stark contrast,O. viverrini was more widely distributed, with infections documented in 721 locations across Thailand, Laos, Cambodia, and vietnam. Critical environmental determinants were quantitatively analyzed, revealing annual mean temperatures ranging between 14 and 20 °C in clonorchiasis-endemic areas and 24–30 °C in opisthorchiasis regions (P vietnam delineates the coexistence and geographical boundaries ofC. sinensis andO. viverrini, revealing distinct endemic zones and a transitional area where both live

关键词： Liver fluke Clonorchiasis Opisthorchiasis Clonorchis sinensis Opisthorchis viverrine Southeast Asia Machine learning Ecological study

Behavior of noncircular tunnels excavated in stratified rock masses-Case of underground coal mines

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 99-110页

作者： Ngoc Anh Do Daniel Dias Van Diep Dinh Tien Tung Tran Van Canh Dao viet Doan Dao Phuc Nhan nguyen Department of Underground and Mining Construction.Faculty of Civil Engineering Hanoi University of Mining and Ceology School of Automotive and Transportation Engineering Hefei University of Technology Laboratory 35R Crenoble Alpes University

The amount of tunnels excavated along stratified/sedimentary rock masses in Quangninh coal mine area,vietnam, is gradually increasing. Rock mass in Quangninh is characterized by beddings between rock layers. The behavior of stratified rock masses surrounding the tunnels depends on both the intact rock and the beddings between rock layers. The main characteristics of stratified rock masses that need to be considered are their heterogeneity and anisotropy. Depending on the dip angle of rock layers, movements and failure zones developed surrounding the tunnels can be asymmetrical over the vertical axis of tunnel. This asymmetry causes adverse behaviors of the tunnel structures. The objective of this study is to highlight convergences and yielded zones developed in rock masses surrounding noncircular tunnels in Quangninh coal mine area using a finite element method. The presence of bedding joints is explicitly simulated. The numerical results indicated that with the increase in dip angle of bedding joints, the stress asymmetry over the tunnel vertical axis increases. It gradually leads to an asymmetry of the failure zone surrounding the tunnel. An increase of rock mass quality means a decrease of rock mass sensitivity to the discontinuities. In addition,a dip angle of the bedding joints of approximately 45° could be considered as the critical angle at which the rock mass mechanism changes between sliding and bending.

关键词： Tunnel Bedding Stratification Anisotropic Heterogeneity