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FAULT CAUSED BY WATER PRESSURE IN THE HEAD-COVER CHAMBER

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Journal of Hydrodynamics 2006年第3期18卷 280-286页

作者： PEI Hai-lin QI Xue-yi li hui li jian-hui PEI Ze-yu College of Fluid Power and Control Lanzhou University of Technology Lanzhou 730050 China Gansu Electrical and scientifical Institute Lanzhou 730050 China Vernon Barford School Edmonton Alberta T6J2X6 Canada

Owing to the high temperature of the thrust beating pads, the No.l unit wasn＇t performed in the upgrading test at liujiaxia Hydropower Plant. Through the experimental and theoretical analysis, it has been confirmed that the fault unit was caused by the high water pressure in the head-cover chamber. This type of the fault is out-of-the-way. After the suitable measure wags against the fault were taken, the No. 1 unit can stably operate. The conclusions and the methodology are of the certain reference value to the fault-diagnosis of the hydroelectric unit.

关键词： hydroelectric unit perturbation vibration,fault diagnosis

Formation Mechanism and Binding Energy for Body-Centred Regular Tetrahedral Structure of li5

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Communications in Theoretical Physics 2006年第5期45卷 914-918页

作者： li Ping YANG jian-hui GOU Qing-Quan Institute of Atomic and Molecular Physics Sichuan University Chengdu 610065 China

The formation mechanism for the body-centred regular tetrahedral structure of li5 cluster is proposed. The curve of the total energy versus the separation R between the nucleus at the centre and nuclei at the apexes for this structure of li5 has been calculated by using the method of Gou＇s modified arrangement channel quantum mechanics （MACQM）, The result shows that the curve has a minimal energy of-37.2562 a.u. at R =14.5α0. When R approaches infinity the total energy of five lithium atoms has the value of-37.1401 a.u. So the binding energy of li5 with respect to five lithium atoms is the difference of 0.1161 a.u. for the above two energy values. Therefore the binding energy per atom for li5 is 0.023 22 a.u., or 0.632 eV, which is greater than the binding energy per atom of 0.453 eV for li2 and the binding energy per atom of 0.494 eV for li3 calculated previously by us. This means that the li3 cluster may be formed stably in a body-centred regular tetrahedral structure with a greater binding energy.

关键词： li5 cluster formation mechanism binding energy

Syntheses,Crystal Structures and Bioactivities of Two Novel Isatin Derivatives

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Chemical Research in Chinese Universities 2011年第4期27卷 595-598页

作者： SHANG jian-li li hui-dong SHANG Jun SONG Hai-bin li Zheng-ming WANG jian-guo State Key Laboratory of Elemento-Organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tianjin 300071 P. R. China

Two novel compounds 1-（4-fluorobenzyl）-4-chloro-（Z）-3-benzoylhydrazono-2-indolinone（1） and 1-（4-methoxybenzyl）-（Z）-3-benzoylhydrazono-2-indolinone（2） were synthesized and their crystal structures were determined by single-crystal X-ray *** 1（C22H15ClFN3O2） crystallized in the triclinic system,space group P1·with a=0.94198（19） nm,b=1.4339（3） nm,c=1.5018（3） nm,α=101.58（3）°,β=102.96（3）°,γ=102.73°,V=1.8602（6） nm3,Mr=407.82,Dc=1.456 g/cm3,μ=0.240 mm-1,F（000）=840,Z=4,R1=0.0442 and wR2=*** 2（C23H19N3O3） crystallized in the triclinic system,space group P1·with a=1.0022（2） nm,b=1.0192（2） nm,c=1.0461（2） nm,α=99.86（3）°,β=117.30（3）°,γ=94.13（3）°,V=0.9215（3） nm3,Mr=385.41,Dc=1.389 g/cm3,μ=0.094 mm-1,F（000）=404,Z=2,R1=0.0403 and wR2=*** preliminary herbicidal activities of the two compounds were also evaluated.

关键词： Acetohydroxy acid synthase(AHAS) Crystal structure Isatin derivative Herbicidal activity

Test and numerical investigations on static and dynamic characteristics of extra-wide concrete self-anchored suspension bridge under vehicle loads

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Journal of Central South University 2017年第10期24卷 2382-2395页

作者： ZHOU Guang-pan li Ai-qun li jian-hui DUAN Mao-jun School of Civil Engineering Southeast University Beijing Advanced Innovation Centre for Future Urban Design Beijing University of Civil Engineering and Architecture School of Civil Engineering Nanjing Forestry University

The present work is aimed at studying the mechanic properties of the extra-wide concrete self-anchored suspension bridge under static and dynamic vehicle loads. Based on the field test using 12 heavy trucks and finite element simulations, the static deformations of different components, stress increments and distributions of the girder, as well as the vibration characteristics and damping ratio of the Hunan Road Bridge were analyzed, which is the widest self-anchored suspension bridge in China at present. The dynamic responses were calculated using the Newmark-β integration method assisted by the simulation models of bridge and vehicles, the influences on the dynamic impact coefficient(DIC) brought by the vehicle parameters, girder width, eccentricity travel and deck flatness were also researched. The spatial effect of the girder is obvious due to the extra width, which performs as the stress increments distribute unevenly along the transverse direction, and the girder deflections and stress increments of the upper plate change as a "V" and "M" shape respectively under the symmetrical vehicle loads affected by the shear lag effect, cross slope and local effect of the wheels, the maximum of stress increments are located in the junctions with the inner webs. The obvious girder torsional deformation and the apparent unevenness of the hanger forces between the two cable planes under the eccentric vehicle loads, together with the mode shapes such as the girder transverse bending and torsion which appear relatively earlier, all reflect the weakened torsional rigidity of the extra-wide girder. The transverse displacements of towers are more obvious than the longitudinal ones. As for the influences on the DIC, the static effect of the heavier vehicles plays a major role when pass through with a higher speed and the changes of vehicle suspension stiffness generate greater impacts than the suspension damp. The values of DIC in the vehicle-running side during the eccentric tra

关键词： self-anchored suspension bridge extra-wide girder field test simulation vehicle loads increments distribution damping ratio mode shape dynamic impact coefficient

Silencing of Bcl-2 gene expression by siRNA transfection in- hibits the protective effect of fluvastatin against cell apoptosis in human aortic endothelial cells

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Journal of Geriatric Cardiology 2008年第1期5卷 33-38页

作者： Wenwen Zhong Yang liu jian li hui Tian Department of Geriatric Endocrinology Chinese PLA General HospitalBeijing 100853China Department of Geriatric EndocrinologyChinese PLA General HospitalBeijing 100853China Department of Geriatric EndocrinologyChinese PLA General HospitalBeijing 100853China Department of Geriatric EndocrinologyChinese PLA General HospitalBeijing 100853China

Objective To study the protective effect of fluvastatin,one of the HMG-CoA reductase inhibitors (statins),against oxygen radical-induced oxidative damages in human aortic endothelial cell,and the role of Bcl-2 in this *** Human aortic endothelial cells with or without Bcl-2 siRNA transfection were subjected to 1-100 nM of fluvastatin and 100 la hydrogen peroxide for 24 ***-2 mRNA and protein expression were measured by Taqman quantitative PCR and Western *** apoptosis was measured by normal and fluorescent microscopy and Cell Death Detection *** In the Bcl-2-expressed cells,fluvastatin significantly reversed hydrogen peroxide-induced microscopic apoptosis and apoptotic DNA fragmentation,which were accompanied by a markedly upregulation of Bcl-2 expression by ***,the endothelial protection by fluvastatin was completely lost in Bcl-2 siRNA transfected *** Fluvastatin protects human endothelial cells against oxygen radical-induced cell apoptosis in vitro,and this protection seemed to be mediated in a Bcl-2 dependent pathway.(J Geriatr Cardil 12008;5:33-38)

关键词： fluvastatin,Bcl-2,gene silencing,apoptosis

Association between Organophosphate Exposure and Mental Health among Rural Residents from Two Towns in China

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Biomedical and Environmental Sciences 2022年第2期35卷 165-169页

作者： ZHU jian CUI Jia Jing GU Yu Lu li jian hui BESELER Cheryl L STALLONES Lorann KAN Mu Jie REN Shu Ping Department of Occupational Health and Environmental Health School of Public HealthJilin UniversityChangchun 130021JilinChina Radiation Medicine Key Laboratory of Ministry of Health School of Public HealthJilin UniversityChangchun 130021JilinChina Department of Teaching Management Chengde Medical CollegeChengde 067000HebeiChina Department of Environmental Agricultural and Occupational HealthCollege of Public HealthUniversity of Nebraska Medical CenterOmahaNebraskaUSA 68198-4388 Colorado Injury Control Research Center Department of PsychologyColorado State UniversityFort CollinsColoradoUSA 80525-1876 Department of Biochemistry College of Basic MedicineJilin UniversityChangchun 130021JilinChina

Organophosphate(OP)pesticides are a class of chemicals that are typically derived from phosphoric,phosphonic,and phosphinic acids,and are commonly used in agriculture[1].China is the largest producer of pesticides and one of the most intensive pesticide users in crop production in the *** poisoning has been shown to be an important public health problem among Chinese farm workers[2].Multiple routes of exposure to OP pesticides occur through food contamination,environmental and household pollution,proximity to agricultural fields,and agricultural work[3].

关键词： pesticides typically agricultural

Case Control Study of Impulsivity,Aggression,Pesticide Exposure and Suicide Attempts Using Pesticides among Farmers

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Biomedical and Environmental Sciences 2018年第3期31卷 242-246页

作者： LYU Chun Ping PEI jian Ru BESELER L. Cheryl li Yu ling li jian hui REN Ming STALLONES Lorann REN Shu Ping Department of Occupational and Environmental Health School of Public Health Jilin University Changchun 230022Jilin China Center for Disease Prevention and Control of Yanzhou District Jining City Shandong Province Jining 272100 Shandong China Colorado Injury Control Research Center Department of Psychology Colorado State University FortCollins Colorado USA 80525-1876 Department of Information Retrieval School of Public Health Jilin UniversityChangchun 130021 Jilin China

A case-control study was conducted to investigate associations between organophosphate pesticide（OP）exposure,aggression,impulsivity,and attempted *** were used to collect information;impulsivity and aggression were ... 详细信息

关键词： Case Control Study of Impulsivity,Aggression,Pesticide Exposure and Suicide Attempts Using Pesticides among Farmers OP

Structural characteristics and mechanism of hydrogen-induced disproportionation of the ZrCo alloy

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International Journal of Minerals,Metallurgy and Materials 2012年第11期19卷 1010-1015页

作者： Xiu-mei Guo Shu-mao Wang Xiao-peng liu Zhi-nian li jian-hua Ye hui-ping Yuan li-jun jiang Energy Material and Technology Institute General Research Institute for Nonferrous Metals Beijing 100088 China

The intermetallic compound ZrCo was prepared, and its hydrogen-induced disproportionation in hydrogen desorption processes was investigated. The hydrogenation-dehydrogenation thermodynamics of the ZrCo alloy was evaluated by pressure-composition isotherm measurements at different temperatures. The kinetic processes of hydrogen-induced disproportionation at different temperatures under certain pressures were detailedly studied. The disproportionation rate of the ZrCo alloy increased with the increases of temperature and initial hy- drogen pressure under experimental conditions. However, the maximum attainable extent of disproportionation did not change much with an increase in temperature or initial hydrogen pressure. The crystallographic structure analysis of the ZrCo alloy combining with its corre- sponding dehydrogenation kinetic curves under the conditions of an initial hydrogen pressure of 0.2 MPa and a temperature of 723 K indi- cated that the basic process of disproportionation reactions was composed of four stages： rapid dehydrogenation of ZrCoH3, equilibrium of dehydrogenation, simultaneity of dehydrogenation and disproportionation, and completion of disproportionation.

关键词： zirconium compounds cobalt compounds hydrogenation dehydrogenation structural analysis thermodynamics

Pathogenicity of GB virus C on virus hepatitis and hemodialysis patients

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World Journal of Gastroenterology 2003年第8期9卷 1739-1742页

作者： Wan-Fu Zhu li-Min Yin Peng li jian Huang hui Zhuang, Department of Microbiology, School of Basic Medical Sciences, Peking University, Beijing 100083, China Department of Microbiology School of Basic Medical Sciences Peking University Beijing 100083 China. zhuwanfu@***

AIM: To determine the pathogenicity of GB virus C (GBV-C)on liver and the effects of its co-infection on the clinical features and prognosis of patients with hepatitis B and ***: Cross-sectional study was carried out in 413patients with acute, chronic hepatitis B or liver cirrhosis,and in 67 hemodialysis patients. A 20-month prospective cohort study was carried out in 95 hepatitis B and 80 hepatitis C patients. A reverse transcriptase nested polymerase chain reaction (RT-nPCR) of the 5′-noncoding region was used to detect circulating GBV-C RNA. liver function was determined by an automated analyzer for all ***: The prevalence of GBV-C in the high-risk populations with the virus transmitted via blood was high,ranging from 16.2 to 28.8%. Co-infection with GBV-C in hepatitis B patients did not affect the clinical features of the disease or liver function. The dialysis patients infected with GBV-C alone did not develop functional changes to the *** cohort study showed that GBV-C co-infection did not affect the clinical features, prognosis or negative serum conversion rate of chronic hepatitis B and ***: The results suggest that GBV-C has no marked pathogenicity on liver, so it may not be a hepatitis virus.

关键词：病毒性肝炎血液透析 GB病毒病原学