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草酸促进双酚A在黏土矿物悬浮液中光降解研究

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环境科学学报 2009年第12期29卷 2585-2590页

作者：刘延湘 vu thi thu Anh 吴峰江汉大学化学与环境工程学院武汉430056 越南科学与技术院海洋地质与地球物理研究所河内100803 武汉大学资源与环境学院武汉430072

选择两种常见的天然黏土矿物高岭石和蒙脱石,研究了有机污染物双酚A(BPA)在其表面的吸附及草酸对黏土矿物悬浮液中BPA光降解的影响.结果表明,BPA在两种黏土矿物表面的吸附量较小,吸附符合Langmuir等温式.在250W金属卤化物灯(λ≥360nm)... 详细信息

选择两种常见的天然黏土矿物高岭石和蒙脱石,研究了有机污染物双酚A(BPA)在其表面的吸附及草酸对黏土矿物悬浮液中BPA光降解的影响.结果表明,BPA在两种黏土矿物表面的吸附量较小,吸附符合Langmuir等温式.在250W金属卤化物灯(λ≥360nm)照射下,草酸可显著促进BPA在高岭石和蒙脱石悬浮液中的光降解,降解动力学符合Langmuir-Hinshelwood方程.降解速率受pH值的影响较大,pH=4.0时速度最快,光降解速率同时受草酸浓度的影响.最后,通过分析矿物中铁的化学环境及反应过程中铁浓度变化,分析了草酸促进BPA在黏土矿物悬浮液中光降解的可能机制.

关键词：草酸双酚A 天然高岭石天然蒙脱石光降解

Nutritional Practices among Ethnic Minorities and Child Malnutrition in Mountainous Areas of Central Vietnam

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Food and Nutrition Sciences 2013年第1期4卷 82-89页

作者： Le thi Huong vu thi thu Nga Institute of Preventive Medicine and Public Health Hanoi Medical University Hanoi Vietnam.

Background: Despite the success of National Action Plan on Nutrition program in reducing malnutrition among children under 5 years old in Vietnamin recent years, the rate of malnutrition inVietnamremains higher than that rate in other surrounding countries. The rate is especially high in mountainous areas. this study aims to explore the association between the mother’s nutrition care practice and the nutritional status of their children. Methods: 400 Children under 5 years of age and their mothers from Thanh Hoa—a Northern Province of Vietnam were included in this survey. Weight and height of the children were measured. Information related to the mother’s knowledge and practices pertaining to child health care and nutrition was collected. Results: The malnutrition rate was 29.3% by weight for age score (WAZ), 28.3% by height for age score (HAZ) and 10.0% by weight for height score (WHZ). 27.3% of mothers discarded the colostrum milk. 21.3% of children were fed with chewing rice before breastfeeding. Exclusive breastfeeding up to four months was 17.8% and exclusive breastfeeding rates for 6 months or more was 8.6%. Weaning practice before four months of age was 53.7%. There was an association between malnutrition with mother’s ethnic group, and the frequency of consumption of protein rich food. Conclusion: Malnutrition of ethnic minority children under five years of age is still a public health problem in the central mountainous areas ofVietnam. Inappropriate breastfeeding and weaning practice among ethnic minority women were associated with this high rate. Further effort should continue to improve the nutrition status of ethnic minority children under 5 years of age. Customized, culturally adapted interventions for ethnic minority women to strengthen their nutrition care knowledge, attitude and practice, especially breastfeeding and weaning practice are the key to achieving better nutrition status of their children.

关键词： Malnutrition Children Knowledge and Practice Vietnam

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

An isogeometric approach for nonlocal bending and free oscillation of magneto-electro-elastic functionally graded nanobeam with elastic constraints

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Frontiers of Structural and Civil Engineering 2024年第9期18卷 1401-1423页

作者： thu Huong NGUYEN thi Van Ke TRAN Quoc Hoa PHAM School of Mechanical and Automotive Engineering Hanoi University of IndustryHanoi 100000Vietnam Faculty of Mechanical Engineering Le Quy Don Technical UniversityHanoi 100000Vietnam Faculty of Engineering and Technology Nguyen Tat Thanh UniversityHo Chi Minh City 700000Vietnam

this work uses isogeometric analysis(IGA),which is based on nonlocal hypothesis and higher-order shear beam hypothesis,to investigate the static bending and free oscillation of a magneto-electro-elastic functionally graded(MEE-FG)nanobeam subject to elastic boundary constraints(BCs).The magneto-electric boundary condition and the Maxwell equation are used to calculate the variation of electric and magnetic potentials along the thickness direction of the *** study is innovative since it does not use the conventional boundary ***,an elastic system of straight and torsion springs with controllable stiffness is used to support nanobeams’beginning and end positions,creating customizable *** governing equations of motion of nanobeams are established by applying Hamilton’s principle and IGA is used to determine deflections and natural frequency *** studies were performed to evaluate the convergence and accuracy of the proposed *** from this,the impact of the input parameters on the static bending and free oscillation of the MEE-FG nanobeam is examined in *** findings could be valuable for analyzing and designing innovative structures constructed of functionally graded MEE materials.

关键词： elastic boundary conditions isogeometric analysis nanobeam via nonlocal theory grading of magneto-electro-elastic functions

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中国与越南县级土地利用规划体系对比研究

中国与越南县级土地利用规划体系对比研究

作者： vu thi thu HUONG（武氏秋红）昆明理工大学

学位级别：硕士

土地利用总体规划是在一定区域内,根据国家社会经济可持续发展的要求和当地自然、经济、社会条件,对土地的开发、利用、治理、保护在空间上、时间上所作的总体安排和布局。近几年来,越南较快的经济增长速度已经向土地资源及水资源施压... 详细信息

土地利用总体规划是在一定区域内,根据国家社会经济可持续发展的要求和当地自然、经济、社会条件,对土地的开发、利用、治理、保护在空间上、时间上所作的总体安排和布局。近几年来,越南较快的经济增长速度已经向土地资源及水资源施压、从而引起了重新调整符合于经济快速发展的土地利用规划的需求。同时、气候变化也成为越南发展过程当中的一个新挑战。这些挑战主要包括影响到生活的挑战、生计、自然资源和社会结构等挑战。越南被视为承受气候变化和海平面上升最大影响的两个国家之一。“越南应对气候变化国家目标”的具体目标之一是在经济社会发展计划及全国各地各部门规划战略里集成了气候变化因素;加入世界贸易组织(wTO)也需要对符合于发展水平的土地利用规划及符合于全球化趋势的土地利用规划近性重新调整。因此我们需要扩大土地利用规划的作用范围、包括环境因素、气候变化、经济社会。同时也要为承受土地使用改革的影响的人或集体参加规划过程创造便利条件。这样,将以前不灵活和偏于描述的规划方法转为偏于分析和具有战略性的规划方法已成为土地利用规划过程当中的急需方法。越南土地利用规划的建设在土地法及有关法律文件都有规定。土地利用规划的任务就是划分土地以满足经济、社会发展及环保的要求;同时确保合理、节省、有效地使用土地。目前越南土地管理的法律法规指出、每个土地规划方案都要考虑到与经济、社会及环境相关的关系,同时也要支持各级基层的直接承受影响的对象对每个规划方案积极提出意见。然而在越南,这样的实际参考性的例子还不多,对省级和区级关于实际应用上如何展开的引导还缺乏。中国人多地少、耕地资源缺乏、水土流失、土地退化等生态环境问题日趋严重。走中国特色农业现代化道路全面建设小康社会、随着经济社会的快速发展、对土地的需求量日益矿大、土地供需之间的矛盾也随之加剧。面对人地矛盾十分尖锐的基本国情、必须对有限的土地资源精打细算、严格控制建设用地供应总量、坚决遏制盲目投资和低水平重复建设等行为。为实现土地资源的可特续利用和经济社会可特续发展、必须节约与集约利用土地资源、实行更为严格的耕地保护制度。2005年中国开展好规划实施评价、基础调查、资料搜集和课题研究等规划修编前期工作、为规划修编打下良好基础。2010年、各级土地利用规划编制主要工作基本完成。这些因素和背景条件为发展带来了机遇、必将加强土地规划理论、方法和技术手段研究、借鉴国内外土地利用先进经验和方式、促进土地利用规划学科发展。本课题选取“中国与越南县级土地利用规划体系对比研究”,从加强合作交流,借鉴国内外土地利用先进经验的目的。论文研究的目的： 1、针对目前越南和中国土地利用规划体系对比研究,初步结构分明,功能清晰的土地利用规划体系,分析研究县级土地利用规划的任务和内容。 2、针对目前土地利用规划的目标单一问题,深刻分析土地利用目标的内涵,揭示土地利用规划目标的实质,提出越南和中国县级土地利用规划预期目标。 3、根据规划目标和规划内容的层次性,中国与越南县级规划的控制指标体系对比研究。 4、拟对中国与越南县级土地利用规划的内容和方法进行初步探讨。

关键词：土地利用规划系统结构目标指标县级

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

A mediation system for continuous spatial queries on a unified schema using Apache Spark

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Big Earth Data 2024年第1期8卷 115-141页

作者： thi thu Trang Ngo François Pinet David Sarramia Myoung-Ah Kang UniversitéClermont Auvergne ISIMAAubièreFrance UniversitéClermont Auvergne INRAEUR TSCFClermont-FerrandFrance UniversitéClermont Auvergne CNRS/IN2P3LPCClermont-FerrandFrance

Recent advances in big and streaming data systems have enabled real-time analysis of data generated by Internet of things(IoT)systems and sensors in various *** this context,many applications require integrating data from several heterogeneous sources,either stream or static *** such as Apache Spark are able to integrate and process large datasets from different ***,these frameworks are hard to use when the data sources are heterogeneous and *** address this issue,we propose a system based on mediation techniques for integrating stream and static data *** integration process of our system consists of three main steps:configuration,query expression and query *** the configuration step,an administrator designs a mediated schema and defines mapping between the mediated schema and local data *** the query expression step,users express queries using customized SQL grammar on the mediated ***,our system rewrites the query into an optimized Spark application and submits the application to a Spark *** results are continuously returned to *** experiments show that our optimizations can improve query execution time by up to one order of magnitude,making complex streaming and spatial data analysis more accessible.

关键词： Streaming data streaming data integration mediator geospatial data continuous queries

Pattern of smoking cessation and its associated factors in Vietnam

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Health 2012年第6期4卷 289-296页

作者： Le thi Huong Hoang Van Minh Kim Bao Giang Le thi Thanh Xuan vu thi thu Nga Pham Quynh Nga Phan thi Hai Jason Hsia Center for Disease Control and Prevention Atlanta USA Institute for Preventive Medicine and Public Health Hanoi Medical University Hanoi Vietnam Vietnam Steering Committee on Smoking and Health (VINACOSH) Hanoi Vietnam World Health Organization Office in Vietnam Hanoi Vietnam

Background: Even though the number of research on tobacco in Vietnam has recently increased rapidly, there remains a lack of reporting on the pattern of quit smoking and its correlates. It is necessary to have scientific evidence on this issue to help the policy makers and the Public Health sector to have appropriate intervention program to enhance the smoke cessation smoke program and improve the health status of the smokers. this study aims to: (1) Describe the pattern of smoking cessation in Vietnam 2010. (2) Examine the association between smoking cessation with some associated factors in Vietnam 2010. Methods: Data used in this paper were obtained from the Global Adult Tobacco Survey (GATS) conducted in Vietnam in 2010. A total of 11,142 households were selected for this survey using a two-phase sampling design analogous to a three-stage stratified cluster sampling. Both descriptive and analytical statistical analyses were carried out. Multivariate logistic regression modeling was performed to examine the association between the patterns of quit daily;quit smoke;attempt to quit and intend to quit among smokers with relevant factors. Results: The prevalence of the different type of cessation among male and female were 23.3% and 28.6% for quit daily;19.1% and 1.0% for quit;55.6% and 44.4% for attempt to quit and 29.6% and 19.3% for intend to quit respectively. The prevalence of quit daily and quit increased with age whereas attempt to quit decreased with age. Prevalence of cessation was highest among the group who were asked about smoking tobacco by health care providers. Some determinants of quit daily and quit include age, area, and knowledge of illnesses caused by smoking. There was no association between attempt and intend to quit with any socio-characteristic except for area. People in rural area were 2.1 and 1.7 times more likely attempt to quit and intend to quit than those in urban area, respectively. Conclusion: The GATS Vietnam 2010 showed that the prev

关键词： Cessation Socio-Demographic Factors Global Adult Tobacco Use Survey Vietnam

Nonlocal isogeometric analysis for bidirectional functionally graded porous curved microbeams with arbitrary boundary conditions

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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