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Model test of the tunnel subjected to high water pressure in Jinping Second Cascade Hydropower Station,China

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Science China(Technological Sciences) 2011年第S1期54卷 192-198页

作者： WANG JianXiu 1,2.FENG Bo 2.HU LiSheng 2.TIAN PuZhuo 2.SUI DongChang 2.TANG YiQun 1,2.&YANG Ping 1,2.1 Key Laboratory of Geotechnical and Underground Engineering of ministry of education,Tongji University,Shanghai 2.0092.China 2.Department of Geotechnical Engineering,Tongji University,Shanghai 2.0092.China 1. Key Laboratory of Geotechnical and Underground Engineering of ministry of education Tongji University Shanghai 200092 China2. Department of Geotechnical Engineering Tongji University Shanghai 200092 China

In the area with high groundwater pressure,grout curtain is often adopted to reduce the water pressure on tunnel lining.A series of model tests for the diversion tunnel of the Jinping Second Cascade Hydropower Station,China,is designed to study the effect of grout *** impact of the thickness of grout curtain,permeability of grout curtain,internal water pressure and drainage inflow on the distribution of water pressure are *** results indicates that under un-drained condition,water pressure is equal to hydrostatic one no matter grout curtain is selected or not,water pressure under drained condition is far less than that of un-drained condition,drainage in tunnel can reduce tunnel water pressure *** same inflow,both increasing of thickness and decrease of hydraulic conductivity of grout curtain can reduce water pressure *** the same water pressure,the smaller inflow of grout curtain,the less volume of water to be *** impact of hydraulic conductivity of grout curtain is more obvious than that of *** increasing of internal water pressure,the water pressure of grout curtain increases too,and the water pressure increases nearly *** proposed thickness of grout curtain for the diversion tunnels is 16 m.

关键词： tunnel grout curtain water pressure model test

Effects of Current Frequency on the Microstructure and Wear Resistance of Ceramic Coatings Embedded with SiC Nano-particles Produced by Micro-arc Oxidation on AZ91D Magnesium Alloy

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Journal of Materials Science & Technology 2010年第10期26卷 865-871页

作者： Yue Yang and Hua Wu Key Laboratory of Advanced Structural Materials,ministry of education,Changchun University of Technology,Changchun 130012.China [a] Key Laboratory of Advanced Structural Materials ministry of education Changchun University of Technology Changchun 130012 China

To improve the surface wear resistance of the ceramic coating fabricated by micro-arc oxidation （MAO） on AZ91D magnesium alloy,ceramic coatings embedded with SiC nano-particles at different current frequency （500 Hz,700 Hz,and 900 Hz） were produced during the MAO *** morphology and phase composition of the coatings were investigated by scanning electron microscopy （SEM）,field emission scanning electron microscopy （FESEM）,and X-ray diffraction （XRD）.The surface roughness of the coatings was characterized by confocal laser scanning microscopy （CLSM）.Simultaneously,the tribological properties of the composite coatings were evaluated by using a universal materials tester （UMT）.The results shows that the wear resistance of the ceramic coatings with SiC nano-particles was improved significantly compared to the ceramic coatings without SiC ***,the composite coating formed at current frequency 900 Hz showed the better wear resistance than the others.

关键词： Magnesium alloy Micro-arc oxidation SiC nano-particles Wear resistance

Comparison of photovoltaic devices based on MEH-PPV with various molecular weights

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Chinese Science Bulletin 2004年第21期49卷 2259-2261页

作者： KANG Bonan1,2. WANG Liduo1, YANG Yong1 & QIU Yong1 1. Key Laboratory of Organic Optoelectronics & Molecular Engineering of ministry of education, Department of Chemistry, Tsinghua Univer- sity, Beijing 100084, China 2. State Key Laboratory on Integrated optoelectronics, Jilin University Region, Changchun 13002., China Key Laboratory of Organic Optoelectronics & Molecular Engineering of ministry of education Department of Chemistry Tsinghua University Beijing 100084 China

Polymer photovoltaic devices based on poly (2. methoxy-5-(2. -ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH- PPV) with three weight-average molecular weights (Mw) have been fabricated with the device structure of ITO/PEDOT/ MEH-PPV/Ca/Ag, and the effect of the molecular weight on photovoltaic properties has been investigated. The experi- mental results show that the high molecular weight of MEH- PPV leads to low series resistance (Rs) and high short-circuit current. The low molecular weight of MEH-PPV leads to high shunt resistance (Rsh) and high open-circuit voltage. When the molecular weight is 6×105, the highest power con- version efficiency was observed.

关键词： MEHPPV 分子量光电器件载流子迁移率串联电阻并联电阻聚(2.甲氧基-5-(2.-乙基-乙氧基)-1,4-亚苯基乙烯撑)

Patterns of DNA cytosine methylation between haploids and corresponding diploids in rice

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Science Bulletin 2006年第14期51卷 1721-1728页

作者： ZHANG Hongyu1,2., PENG Hai1,2., LI Yun1,2. XU Peizhou1,2. WANG Xudong1,2.& WU Xianjun1,2.. Rice Research Institute of Sichuan Agricultural University, Wenjiang 611130, Sichuan 2. Key Laboratory of Southwest Crop Genetic Resources and Improve-ment, ministry of education, Sichuan Agricultural University, Ya’an 62.014, China Rice Research Institute of Sichuan Agricultural University Wenjiang 611130 Sichuan Key Laboratory of Southwest Crop Genetic Resources and Improve- ment Ministry of Education Sichuan Agricultural University Ya''an 625014 China

Eighteen pairs of diploid-haploid twin-seedlings were identified and screened out fromspecial rice SARII-62. population. Five pairs of themwere selected and randomly designated as A, B, C, Dand E. Simple sequence repeats (SSR) analysisshowed that there was no difference among 310 siteswhich indicated that there was no base mutation onDNA primary structure. DNA methylation plays animportant role in gene expression regulation duringgrowth and development stages in eukaryotes. Amodified AFLP technique (methylation-sensitiveAFLP, MSAP) was employed to detect the DNA me-thylation patterns in the 5′-CCGG sites of the fivepairs of twin-seedlings. Although no methylationmutation was detected among the five diploids,forty-three methylation mutation sites were foundfrom the corresponding haploids. The MSAP ratios,which were the ratios of MSAP sites to the total am-plified sites, in five haploids were 18.79%, 19.35%,18.49%, 18.45% and 18.75%, respectively. And cor-responding full methylation levels (5′-CmCGG indouble strands) of those haploids were 10.58%,11.3%, 10.11%, 10.09% and 10.34%, *** MSAP and full methylation levels in the fivehaploids were higher than that of their correspondingdiploids, which suggested that hypermethylation oc-curred in some 5′-CCGG sites. Five types of MASPpatterns among the five pairs of twin-seedlings weredetected as follows: (1) no changes, methylation lev-els were the same in both haploids and diploids; (2. demethylation, diploid was methylated but no me-thylation in the same site in haploid; (3) hypermethy-lation, the methylation level in haploid was higher than those in diploid; (4) hypomethylation, methyla-tion in haploid was lower than those in diploid; (5) undecided pattern, change trend of methylation lev-els in haploids was not decided. The bands of 18 sites were reclaimed, then sequenced and searched on website to determine the sites of those sequences on rice chromosomes. The result showed that the methylation mutation in

关键词： rice twin-seedling diploid haploid DNA methylation MSAP.

Synthesis, Crystal Structures and Catalysis of Dinuclear Cd(Ⅱ) Complexes Bridged by Unusual (N,O,O′)-Coordinated α-Amino Acids

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Chemical Research in Chinese Universities 2012年第1期28卷 73-78页

作者： DENG Dong-sheng1,2. WANG Li1, PEI Ya-mei1, FENG Lu2.and LIU Chang-lin1 1. Key Laboratory of Pesticide & Chemical Biology, ministry of education, School of Chemistry, Central China Normal University, Wuhan 430079, P. R. China 2. College of Chemistry and Chemical Engineering, Luoyang Normal University, Luoyang 47102., P. R. China School of Chemistry Central China Normal University Key Laboratory of Pesticide & Chemical Biology Ministry of Education Wuhan 430079 College of Chemistry and Chemical Engineering Luoyang Normal University Luoyang 471022

Four dinuclear amino acid cadmium（II） complexes [Cd2.tren）2.dl-alaninato）]（ClO4）3·H2.（I）, [Cd2.tren）2. （l-alaninato）]（ClO4）3·H2.（II）, [Cd2.tren）2.dl-phenylalaninato）]（ClO4）3（III） and [Cd2.tren）2.l-phenylalaninato）]· （ClO4）3（IV）, constructed from mixed ligands of tris（2.aminoethyl）amine（tren） and racemic or natural amino ac ids（amino acids=dl or l-alanine, and dl or l-phenylalanine）, have been synthesized and characterized by X-ray crys tallography. The structural analysis of complexes I and III reveals that the cadmium centers are coordinated by one tren ligand and one amino acid molecule with the unusual （N,O,O′）-bridged mode, resulting in asymmetric chromo phores of CdN4O and CdN5O in complex I, CdN4O2.and CdN5O in complex III, respectively. The utility of the four complexes as efficient water-compatible Lewis acid catalysts for the direct aldol reaction in water was examined. The reaction proceeded smoothly to afford the corresponding β-hydroxy ketones in up to 99% yield. Moreover, the dias tereoselectivity of the reaction favors the formation of the syn-isomers.

关键词： Dinuclear cadmium(II) complex Amino acid Aldol reaction

Security region based real and reactive power pricing of power system

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Science China(Technological Sciences) 2008年第12期51卷 2095-2111页

作者： YU YiXin1 & WANG YanJun1,2.1 Key Laboratory of Power System Simulation and Control of ministry of education,Tianjin University,Tianjin 300072.China 2.College of Mechanical and Electrical Engineering,Agriculture University of Hebei,Baoding 071001,China Key Laboratory of Power System Simulation and Control of ministry of education Tianjin University Tianjin 300072 China College of Mechanical and Electrical Engineering Agriculture University of Hebei Baoding 071001 China

This paper develops a novel model and an algorithm of security region based real and reactive power pricing of power *** the proposed model,the reactive power production cost is represented as the opportunity *** static voltage stability region in the cut set power space(CVSR) and the practical dynamic security region(PDSR) in the injection power space are used to represent the constraints of voltage stability and transient stability,so that the consideration of this kind of constraints in the optimization becomes very *** the proposed algorithm,a decoupled optimization and iteration method of active power production cost and reactive power production cost is *** to the K-T optimality conditions,the prices of active power and reactive power,and the different components corresponding to the concerned security constraints are *** components of spot prices can reflect the influence of different node power injections on each kind of security constraints,so that through the node price all of the participants in power market can be stimulated to take an active part in maintaining the system *** illustrative example on the New England 10-genetator 39-bus System is used to demonstrate the proposed method.

关键词： static voltage stability region practical dynamic security region opportunity cost spot price active power and reactive power

Molecular dynamics simulation of amorphous segregation in Ag-Rh alloys

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Rare Metals 2003年第3期22卷 164-168页

作者： ZHANG Jingxiang and BIAN XiufangKey Laboratory of Liquid Structure and Heredity of Materials, ministry of education, Shandong University, Jinan 2.0061, China Shandong University Key Laboratory of Liquid Structure and Heredity of Materials Ministry of Education Jinan 250061

Molecular dynamics simulation was carried out to investigate the liquid andamorphous microstructures of binary Ag_x-Rh_((100-x)) (x = 2., 50, 75 in atom fraction) *** feature of homogeneous interatomic binding of Ag-Rh liquid was found and probed, whichcan be retained into amorphous solids upon rapid cooling. Homogeneous binding may occur when thedifference in the elemental atomic sizes is less than 10%. The icosahedra in liquid before theformation of amorphous state exist in a stable state and the network formed by 1551-clusters inmolten alloys would inhibit the crystallization and diffusion of atoms. A higher degree of1551-clusters will be favorable to form metallic glasses.

关键词： metallic glass amorphous segregation molecular dynamics liquid structure Ag-Rh alloy

Relationship between plant species diversity and patch characteristics in a marsh in the Sangjiang Plain,China—Using Yaluhe farm as an example

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Progress in Natural Science:Materials International 2007年第6期17卷 664-669页

作者： Sun Zhonglin1, Xing Fu1,2. Lu Xianguo2. Xu Kun1, Yu Lili1 and Ni Hongwei3(1. Key Laboratory of Vegetation Ecology, ministry of education, Changchun 13002., China 2. Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012. China 3. Natural Resources Instute of Heilongjiang Academy of Sciences, Harbin 150040, China) [a]Key Laboratory of Vegetation Ecology Ministry of Education Changchun China [b]Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchum China [c]Natural Resources Instute of Heilongjiang Academy of Sciences Harbin China

Based on Quick Bird satellite image data, the present study examined small-scale herbaceous community patches in the marsh of the Sanjiang Plain and measured patch characteristics such as the area, perimeter and shape by GPS. The coenological characteristics of the patches were investigated using quadrat method, and the vascular plant species were recorded using transect method. A total of 2.9 plant species were recorded, which represents 12.2. of the vascular flora in Heilongjiang Province. Our results showed that species number S correlated with patch area and perimeter; richness index (R) correlated with patch perimeter; Simpson index (D) correlated with patch area and perimeter/area; Shannon-Wiener index (H′) correlated with patch area, perimeter and perimeter/area; Evenness index (Jsw) correlated with perimeter/area. Both S and R have significant difference between different size of patches. Plant diversity in the small-scale herbaceous communities tended to increase with the patch area and perimeter. We concluded that edge effects and the habitat heterogeneity of the patches are important in determining the number of species. The relative smoothness of the patch edges also affects the plant diversity of the patches. The richness of plant species in the marsh in the Sanjiang Plain is highly sensitive to the small-scale patches, which continues to play an important role in preserving plant diversity in the local area.

关键词： marsh in Sanjiang Plain plant diversity community patch habitat fragmentation small scale edge effect.

Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science China Earth Sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2. WANG Qingfei1,2., HUANG Dinghua3 , WAN Li4, YANG Liqiang1,2.& GAO Bangfei1,2.1. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Beijing 100083, China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of ministry of education, China University of Geo- sciences, Beijing 100083, China 3. Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China 4. School of Mathematics and Information Science, Guangzhou University, Guangzhou 510405, China 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of ministry of education China University of Geosciences Beijing 100083 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China 4. School of Mathematics and Information Science Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.