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Acta Mechanica Sinica 2024年第8期40卷 194-218页

作者： thu-Huong Nguyen Thi van Ke Tran van-Minh Phung van Hai Trinh Quoc Hoa Pham Faculty of Mechanical Engineering Hanoi University of IndustryHanoi100000Vietnam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi100000Vietnam Institute of Vehicle and Energy Engineering Le Quy Don Technical UniversityHanoi100000Vietnam Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City700000Vietnam

This research aims to analyze the static bending and free vibration behaviors of bidirectional functionally graded porous(BFGP)curved microbeams with elastic boundary conditions resting on a Pasternak’s elastic foundation in a hygro-thermal *** analysis based on non-uniform rational B-splines,first-order shear deformation theory,nonlocal elasticity theory combined with the modified strain gradient theories,modified Timoshenko beam theory are formulated to depict bending and shear deformations of BFGP curved ***,because using the modified Timoshenko beam theory,this study removes the requirement for a shear correction factor and describes shear stress by zero at the upper and lower cross-sectional sites of the BFGP curved *** from traditional boundary conditions,where the beginning and end positions of a curved beam are connected by an elastic system of straight and torsion *** allows for greater flexibility in controlling the stiffness of the springs to obtain arbitrary *** assess the accuracy and convergence of the proposed approach,validation numerical examples were conducted in the various examples.

关键词： Bidirectional functionally graded porous material Elastic boundary condition Isogeometric analysis Curved microbeams Nonlocal elasticity theory Modified strain gradient theory

Application of Hydrological Model to Simulate Rainfall-Runoff into An Khe Reservoir in the Ba River Basin, Vietnam

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Journal of Environmental Science and Engineering(A) 2018年第3期7卷 101-107页

作者： Nguyen van Hieu can thu van Vu Minh Cat Ministry of Natural Resources and Environment Ha Noi 100000 Vietnam thuyloi Universiry Ha Noi 100000 Vietnam Hochiminh City University of Natural Resources and Environment HCM City 700000 Vietnam

The BR （Ba River） basin is one of 9 main river basins in Vietnam. In the past 20 years, natural hazards such as flood andinundation have been complex and increased dramatically in both frequency and intensity in the BR basin. Recently, there have beenapproximately 198 large and small operating reservoirs which lead to increase natural hazards in the river basin. An Khe reservoir,one of big reservoirs in the upstream of the Ba river, impacts significantly on flooding in the downstream. This paper useshydrological model to simulate the flows as a basic for the safety operation of An Khe reservoir in order to prevent the downstreamfloods. The results indicate the Nash-Sutcliffe coefficient higher than 0.8 is stable and reliable parameter.

关键词： Ba river basin flood An Khe reservoir hydrographic model rainfall-runoff

Tungsten-based nanocatalysts with different structures for visible light responsive photocatalytic degradation of bisphenol A

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Journal of Environmental Sciences 2024年第5期139卷 569-588页

作者： Hai Bang Truong Thi thu Loan Doan Nguyen Tien Hoang Nguyen van Tam Minh Kim Nguyen Le Gia Trung Jin Seog Gwag Nguyen Tien Tran Optical Materials Research Group Science and Technology Advanced InstituteVan Lang UniversityHo Chi Minh CityViet Nam Faculty of Applied Technology School of TechnologyVan Lang UniversityHo Chi Minh CityViet Nam The University of Da Nang University of Science and Technology54 Nguyen Luong BangDa NangViet Nam The University of Da Nang University of Science and Education459 Ton Duc Thang St.Lien ChieuDa Nang 550000Viet Nam Institute of Veterinary Science and Technology 31ha zoneTrau QuyGia LamHa Noi 12400Viet Nam Department of Physics Yeungnam UniversityGyeongsanGyeongbuk 38541Republic of Korea Center for Advanced Chemistry Institute of Research and DevelopmentDuy Tan University03 Quang TrungDa Nang 550000Viet Nam Faculty of Natural Sciences Duy Tan University03 Quang TrungDa Nang 550000Viet Nam

Environmental pollution,such as water contamination,is a critical issue that must be absolutely ***,three different morphologies of tungsten-based photocatalysts(WO_(3)nanorods,WO_(3)/WS_(2)nanobricks,WO_(3)/WS_(2)nanorods)are made using a simple hydrothermal method by changing the solvents(H_(2)O,DMF,aqueous HCl solution).The as-prepared nanocatalysts have excellent thermal stability,large porosity,and high *** results show all materials have good photocatalytic activity in aqueous media,with WO_(3)/WS_(2)nanorods(NRs)having the best activity in the photodegradation of bisphenol A(BPA)under visible-light *** may originate from increased migration of charge carriers and effective prevention of electron–hole recombination in WO_(3)/WS_(2)NRs,whereby this photocatalyst is able to generate more reactive·OH and·O_(2)^(–)species,leading to greater photocatalytic *** 99.6% of BPA is photodegraded within 60 min when using 1.5 g/L WO_(3)/WS_(2)NRs and 5.0 mg/L BPA at pH ***,the optimal conditions(pH,catalyst dosage,initial BPA concentration)for WO_(3)/WS_(2)NRs are also elaborately *** rod-like heterostructures are expressed as potential catalysts with excellent photostability,efficient reusability,and highly active effectivity in different types of *** particular,the removal efficiency of BPA by WO_(3)/WS_(2)NRs reduces by only 1.5% after five recycling runs and even reaches 89.1%in contaminated lake *** study provides promising insights for the nearly complete removal of BPA from wastewater or different water resources,which is advantageous to various applications in environmental remediation.

关键词： Photodegradation Bisphenol A Tungsten-based nanocatalyst Structure Nanorod

Layer chicken microbiota:a comprehensive analysis of spatial and temporal dynamics across all major gut sections

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1056-1070页

作者： Yadav Sharma Bajagai Thi thu Hao van Nitish Joat Kapil Chousalkar Robert J.Moore Dragana Stanley Institute for Future Farming Systems Central Queensland UniversityRockhamptonQLD 4701Australia School of Science RMIT UniversityBundooraVIC 3083Australia School of Animal and Veterinary Sciences The University of AdelaideRoseworthySouth Australia 5371Australia

Background The gut microbiota influences chicken health,welfare,and productivity.A diverse and balanced microbiota has been associated with improved growth,efficient feed utilisation,a well-developed immune system,disease resistance,and stress tolerance in *** studies on chicken gut microbiota have predominantly focused on broiler chickens and have usually been limited to one or two sections of the digestive system,under con-trolled research environments,and often sampled at a single time *** extend these studies,this investigation examined the microbiota of commercially raised layer chickens across all major gut sections of the digestive system and with regular sampling from rearing to the end of production at 80 *** aim was to build a detailed picture of microbiota development across the entire digestive system of layer chickens and study spatial and temporal *** The taxonomic composition of gut microbiota differed significantly between birds in the rearing and pro-duction stages,indicating a shift after laying *** microbiota compositions were observed between proven-triculus and gizzard,as well as between jejunum and ileum,likely due to their anatomical ***-lus dominated the upper gut in pullets and the lower gut in older *** oesophagus had a high proportion of Proteobacteria,including opportunistic pathogens such as *** abundance of Gallibacterium increased after peak production in multiple gut *** was enriched in the late-lay phase compared to younger birds in multiple gut *** influenced microbial richness and diversity in different *** upper gut showed decreased diversity over time,possibly influenced by dietary changes,while the lower gut,specifi-cally cecum and colon,displayed increased richness as birds ***,age-related changes were inconsist-ent across all organs,suggesting the influence of organ-specific factors in micro

关键词： Chicken microbiota Gut microbiota Layers Spatial variation Temporal variation

Assessment of Salinization in the Main River Systems of Long An Province, Vietnam

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Journal of Environmental Science and Engineering(A) 2017年第8期6卷 381-387页

作者： can thu van Nguyen Thi Tuyet Do Thi Hong Hoa can The Viet Do Mien Nguyen van Hieu Hoehiminh City University of Natural Resources and Environment Ho Chi Minh City 700000 Vietnam Thang Long Joint Stock Company Ho Chi Minh City 700000 Vietnam Hydro-Meteologycal Center of Long An Province Tan An City 850000 Vietnam Ministry of Natural Resources and Environment Ha Noi 100000 Vietnam

Three provinces including Long An, Tien Giang and Dong Thap, located at Dong Thap Muoi area in the Mekong Delta, belong to the southern key economic region of Vietnam. These provinces run from west to east with a vast network of rivers. Among them, VCD （Vam Co Dong）, VCT （Vam Co Tay） and Soai Rap rivers are the three biggest rivers crossing the province. In recent years, the flows of rivers have changed a lot and saline intrusion has been very complicated. Salt water has intruded deeply into the field. In the 2000s, salt water only reached Tuyen Nhon （Thanh Hoa district）, but now it has reached Vinh Hung district, about 50 km far from Tuyen Nhon. In 2016, the maximum of salinity in Xuan Khanh （Duc Hoa district） in VCD river was 6.8‰ and Tuyen Nhon （Thanh Hoa district） in VCT river was 5.2‰. In the coming years, the situation of salt intrusion is going to happen more unpredictable under effects of global climate change and sea level rise.

关键词： Salinization Vam Co river system LA (Long An) province.

Development and Application of a Distributed Conceptual Hydrological Model to Simulate Runoff in the Be River Basin and the Water Transfer Capacity to the Saigon River Basin,Vietnam

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Journal of Environmental Science and Engineering(A) 2020年第1期9卷 1-12页

作者： Vu van Nghi Ha Bui Nguyen Lam Tai Pham Anh can thu van Institute for Computational Science and Technology Ho Chi Minh City 700000Vietnam University of Science Vietnam National UniversityHo Chi Minh City 700000Vietnam Dalat University Lam Dong Province 66000Vietnam Institute for Science and Technology Innovation Ho Chi Minh City 700000Vietnam Ho Chi Minh City University of Natural Resources and Environment Ho Chi Minh City 700000Vietnam

A distributed conceptual model(FRASC(Flow Routed Accumulation Simulation in a Catchment))has been developed,in which a rainfall-runoff module is modified from an original lumped conceptual model(Xinanjiang)via a GIS(Geographic Information System)-aided approach and a water allocation module contains reservoirs,water users and hydropower *** model is relatively easy to use and can easily obtain input data,but still has the ability to generate hydrological information at many points within a *** model application to the Be River basin is evaluated and shows to be reliable in terms of close agreements between simulated and observed *** natural flow rates for 36 years are simulated at 7,981 grid cells within a studied area of 7,650 km^*** on this simulated database,design discharges are predicted in various ***,the research determines that the water transfer capacity from the Be River basin to the Saigon River basin reaches 14%,18% and 23% of a planned value of 75 m^3/s during the dry period in a wet year(P10%),average year(P50%)and dry year(P90%),respectively.

关键词： Be River basin distributed conceptual hydrological model FRASC

Establishing the Basic Indicator for the Calculation of the Flood Vulnerability Index for River Basins in Vietnam

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Journal of Environmental Science and Engineering(B) 2016年第8期5卷 390-394页

作者： can thu van Nguyen Thanh Son Phan Vu Hoang Phuong Hydrology Department Faculty of Hydro-Meteorology Hochiminh City University of Natural Resources and Environment Hochiminh City 70000 Vietnam Faculty of Hydro-meteorology & Oceanography Hanoi University of Science Hanoi 100000 Vietnam Climate Change Department Faculty of Hydro-Meteorology Hochiminh City University of Natural Resources and EnvironmentHochiminh City 70000 Vietnam

Along with the concept, the method of assessing the vulnerability is becoming more and more diversified in many directions and fields. In general, these methods can be classified into two groups：（i） direct-qualitative （survey methods, integrated map ...） and （ii） indirectly-quantitative （method index）. The set of indicator plays a very important role in the successful application to any method and brings reliable results. Each basin or area with different natural geography, economics and society and so on, requires a different set of indicator. However, assessing any river basin in Vietnam needs the basic indicator. This study will establish the basic indicator for the construction of flood vulnerability index in Vietnam.

关键词： Vulnerability flood indicator.

Simulation of Flood in the Thach Han-Ben Hai River Basin(Vietnam)under the Influence of the Upstream Reservoir System

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Journal of Environmental Science and Engineering(B) 2021年第6期10卷 227-236页

作者： Ngo Chi Tuan can thu van Nguyen Huu Tuan Nguyen Hai Au Hanoi University of Science Vietnam National UniversityHanoiHa Noi 1000000Vietnam Ho Chi Minh City University of Natural Resources and Environment Ho Chi Minh City 700000Vietnam Institute for Environment and Resources Vietnam National UniversityHo Chi Minh CityHo Chi Minh City 700000Vietnam

The central provinces in Vietnam always suffer from the negative impacts of floods every year,especially in the downstream *** Tri province in the TBRB(Thach Han-Ben Hai River Basin)is one of the provinces suffering heavy damage caused by floods.A 1-dimensional hydrodynamic model was researched and applied connecting 2 dimensions in the MIKE model set(MIKE FLOOD)to simulate inundation level,inundation time,flood flow velocity for communes in *** results for 111 communes in Quang Tri province show that:39 communes(35%)are not flooded;3 communes are flooded below 0.5 m;15 communes are flooded from 0.5-1.0 m,flooding time is about 1 day;30 communes are flooded from 1.0-2.0 m,inundation time is about 2 days;30 communes are flooded over 2.0 m,flooded for about 3 days,especially 3 communes are flooded over 4.0 *** result helps to develop flood prevention plans for localities in the province.

关键词： Thach Han-Ben Hei River basin flood simulation Quang Tri province hydrodynamic model

Transient response of doubly-curved bio-inspired composite shells resting on viscoelastic foundation subject to blast load using improved first-order shear theory and isogeometric approach

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Defence Technology（防务技术） 2024年第8期38卷 171-193页

作者： thuy Tran Thi thu Tu Nguyen Anh Hue Nguyen Thi Hong Nguyen Thi School of Mechanical and Automotive Engineering Hanoi University of IndustryHanoiViet Nam Faculty of Technical Fundamental University of Transport TechnologyHanoiViet Nam Faculty of Mechanical Engineering Thuyloi University175 Tay SonDong DaHanoiViet Nam

Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties and environmental resilience. Biological composite structures with helicoidal schemes and designs have remarkable capacities to absorb impact energy and withstand damage. However, there is a dearth of extensive study on the influence of fiber redirection and reorientation inside the matrix of a helicoid structure on its mechanical performance and reactivity. The present study aimed to explore the static and transient responses of a bio-inspired helicoid laminated composite(B-iHLC) shell under the influence of an explosive load using an isomorphic method. The structural integrity of the shell is maintained by a viscoelastic basis known as the Pasternak foundation, which encompasses two coefficients of stiffness and one coefficient of damping. The equilibrium equations governing shell dynamics are obtained by using Hamilton's principle and including the modified first-order shear theory,therefore obviating the need to employ a shear correction factor. The paper's model and approach are validated by doing numerical comparisons with respected publications. The findings of this study may be used in the construction of military and civilian infrastructure in situations when the structure is subjected to severe stresses that might potentially result in catastrophic collapse. The findings of this paper serve as the foundation for several other issues, including geometric optimization and the dynamic response of similar mechanical structures.

关键词： Blast load Modified first-order shear theory Biological composite structures

Comparative Chemical Research in Essential Oils from Six Apiaceae Species Growing in the Northern Region of Vietnam

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Phyton-International Journal of Experimental Botany 2024年第7期93卷 1677-1687页

作者： Nguyen Quang Hung Nguyen Thanh Tung Nguyen Phuong Hanh Chu Thi thu Ha Nguyen Thi Nhung Nguyen Thai An Vu Xuan Giang Luong van Hao Oleh Koshovyi Ain Raal Institute of Ecology and Biological Resources Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Graduate University of Science and Technology Vietnam Academy of Science and Technology(VAST)Cau GiayHa Noi100000Viet Nam Department of Pharmacognosy Faculty of Pharmacognosy and Traditional MedicineHanoi University of PharmacyHoan KiemHa Noi100000Viet Nam Sa Pa Research Center of Medicinal Materials National Institute of Medicinal MaterialsDien Bien PhuSa PaLao Cai330000Viet Nam Institute of Pharmacy Faculty of MedicineUniversity of TartuTartu50411Estonia

Our study aimed to compare the essential oil(EO)concentration and composition of several Apiaceae species growing in the Northern region of *** yields of EOs from materials ranged from 0.03%(root EO of Angelica acutiloba and aerial parts EO of Heracleum bivittatum)-0.27%(leaf EO of Xyloselinum vietnamense).Gas chromatography-mass spectrometry(GC-MS)allowed the identiﬁcation of 74 components in the EOs of six Apiaceae species,making up 94.4%–100.0%of the *** EO from Angelica acutiloba,(Z)-ligustilide accounted for an extremely large proportion(94.9%).EO of Angelica pubescens was dominated by six character-istic components includingα-pinene(21.5%),β-phellandrene(18.1%),p-cymene(12.2%),3-methylnonane(8.7%),o-cymene(8.1%),and D-sylvestrene(6.2%).The EO from Cryptotaenia japonica was characterized by high amounts ofα-selinene(48.7%),β-selinene(23.7%),and trans-β-farnesene(5.4%).The EOs from leaves and stems of Xyloselinum vietnamense were characterized by high concentrations of sabinene(69.8%and 33.8%),4-terpineol(8.7%and 7.4%)andβ-pinene(4.0%and 6.5%)while EOs from aerial parts and root of Xylo-selinum leonidii comprise four characteristic monoterpenes includingα-pinene(28.2%and 52.8%),β-pinene(7.9%and 10.3%),β-phellandrene(7.6%and 15.3%),and sabinene(3.0%and 4.1%).Additionally,cryptone is also one of the major components in the EO of Xyloselinum leonidii(13.2%in the aerial parts oil and 2.8%in the root oil).In the EOs isolated from the aerial parts and root of Heracleum bivittatum,α-pinene(22.5%and 70.2%)andβ-pinene(43.2%and 20.0%)were the predominant *** appeared in the EO from aerial parts of Heracleum bivittatum with a relatively high concentration(13.5%)while bornyl acetate(5.1%)was also one of the main components in the EO from its aerial parts but was not detected in other Apiaceae species in the present *** databases help identify and control the quality of plant material studied from the family Apiaceae growing in Vietnam.

关键词： Apiaceae essential oil terpenoids gaschromatography-mass spectrometry