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Effect and mechanism of stresses on rock permeability at different scales

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science china Earth sciences 2006年第7期49卷 714-723页

作者： YIN Shangxian1 & WANG Shangxu2 1. Safety Engineering college, North china Institute of science and technology, Yanjiao, beijing 101601, china 2. Key Laboratory of Geophysics Exploration, china university of Petroleum, beijing 100083, china Safety Engineering college North China Institute of Science and Technology Yanjiao Beijing China Key Laboratory of Geophysics Exploration China University of Petroleum Beijing China

The effect of geo-stress fields on macroscopic hydro-geological conditions or micro-cosmic permeability of water-bearing media should follow some laws or principles. Cases study and tests show that: (1) At macro-geologic large scale, deformed and crashed rocks which were induced by geo-stress fields changing provided space for groundwater storage and flow. Groundwater adjusts water-bearing space and dilatants fractures by flowing and press transferring. Coupling of liquid and solid can be implemented for rocks and groundwater. Although tectonic fields witness several times of change and build-up in geological time, stress fields forming regional tectonic framework are coherent with seepage fields, orientation of the maximum horizontal stress demonstrates main seepage direc-tions. (2) At macro-geologic middle scale, zones of stresses changing sharply, quite low stresses, stress or shear concentration can be used to show locations and types of main fractures, zones of geo-stresses changing equably can be acted as normal base media zones of tri-porosity media. (3) At micro-geologic small scale, tri-porosity media include fractured rocks, porous rocks and capillary rocks. Investigations indicate that porosity or permeability is functions of effective stresses, and po-rosity or permeability changing rules of porous rocks with variation of effective stresses can be de-scribed as the index model, the model of power exponent functions is suitable for those of fractured rocks, the model of the second power parabola for capillary rocks. The porosity and permeability loss in fractured rocks, which are greater than that in porous rocks, are shown by calculation of effective compressive coefficient and closing pressure in cracks. The calculations can also explain the mecha-nism why porosity changes are always larger than permeability changes. It is proved by the thick wall cylinder theory that the second power parabola relation between porosity or permeability loss and effective

关键词： geo-stress fields, seepage fields, tri-porosity media, effective stresses, permeability, porosity,scale.

EST-derived microsatellites in P seudosciaena crocea and their applicability to related species

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Acta Oceanologica Sinica 2010年第6期29卷 83-91页

作者： YE Hua WANG Xiaoqing GAO Tianxiang WANG Zhiyong college of animal science and technology Hunan Agricultural University Changsha 410128 China Key Laboratory of science and technology for Aquaculture and Food Safety Fisheries College/Fisheries Biotechnology Institute Jimei University Xiamen 361021 China Key Laboratory of Mariculture Ministry of Education Ocean University of China Qingdao 266003 China

Simple sequence repeat （SSR） markers were obtained for the large yellow croaker Pseudosciaena crocea using 1 205 expressed sequences tags （ESTs） from the NCBI *** for 48 ESTSSR loci were designed and screened with 30 *** specimens captured from Guanjingyang sea area in Fujian Province of *** of the loci were polymorphic,which were amplified with 3 to 11 alleles per locus and the mean of *** observed and expected heterozygosity per locus ranged from 0.091 to 0.844 （mean 0.544） and from 0.118 to 0.892 （mean 0.644）,*** information content （PIC） ranged from 0.115 to 0.866 （mean 0.593）.The results for cross-species amplification of the 16 large yellow croaker EST-SSRs on ***,***,***,*** and *** revealed that 14,12,11,7 and 6 loci were successfully amplified with 1 to 10 alleles with an average of 4.5 per locus,respectively,which are suitable for population genetics studies of these species and useful for phylogenetic relationship analysis among these ***,this study provides a set of type I markers for population genetics studies and genome mapping for large yellow croaker and its closely related species.

关键词： Pseudosciaena crocea EST-SSRs genetic diversity cross-species amplification

Nanostructured Sulfide Composite Coating Prepared by Atmospheric Plasma Spraying

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材料工程 2006年第Z1期34卷 281-284页

作者： GUAN Yao-hui~1,XU Yang~1,ZHENG Zhong-yu~2,TONG Xiao-hui~2(1 Engineering college of china agricultural university,beijing 100083,china 2 beijing Research Institute of Mechanical & Electrical technology,beijing 100083,china) Engineering college China Agricultural University Beijing 100083 China beijing Research Institute of Mechanical and Electrical technology Beijing 100083 China

Nanostructured FeS-SiC coating was deposited by atmospheric plasma spraying（APS）.The microstructure and phase composition of the coating were characterized with SEM and XRD,*** addition,the size distribution of the reconstituted powders and the porosity of the coating have been *** was found that the reconstitiuted powers with sizes in the range of 20 to 80 μm had excellent flowability and were suitable for plasma spraying *** as-sprayed FeS-SiC composite coating exhibited a bimodal distribution with small grains（30～80nm） and large grains（100～200nm）.The coating was mainly composed of FeS and SiC,a small quantity of Fe1-xS and oxide were also *** porosity of the coating was approximately 19%.

关键词： plasma spraying nanostructured FeS-SiC composite coating

Density functional theory study of the magnetic properties of rare earth complexes:the magnetic coupling mechanism in Y~Ⅲ and Gd~Ⅲ complexes with nitronyl nitroxide

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science china Chemistry 2009年第11期52卷 1961-1968页

作者： REN Jie1,2,WANG BingWu1 & CHEN ZhiDa1 1 beijing National Laboratory for Molecular sciences,State Key Laboratory of Rare Earth Materials Chemistry and Applications,college of Chemistry and Molecular Engineering,Peking university,beijing 100871,china 2 college of science,Hebei university of science and technology,Shijiazhuang 050018,china beijing National Laboratory for Molecular sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing China college of science Hebei University of Science and Technology Shijiazhuang China

The magnetic coupling interactions of the nitronyl nitroxide radicals bound to diamagnetic(YⅢ) and paramagnetic(GdⅢ) rare earth ions in two model magnetic systems based on novel rare earth organic radical complexes Ln(hfac)3(NITPhOCH3)2(Ln=YⅢ 1,GdⅢ 2;hafc = hexafluoroacetylacetonate;NIT-PhOCH3 = 4'-methoxyo-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide) have been investigated by density functional theory(DFT).The magnetic coupling mechanisms were also explored from the viewpoint of molecular orbital and spin density *** calculations show that the empty 4d-orbitals of YⅢ and 5d-orbitals of GdⅢ play an important role in the antiferromagnetic coupling between the two nitronyl nitroxide radical ligands,and that the ferromagnetic coupling between the GdⅢ ion and the radical magnetic centers can be attributed to the nearly complete localization of the isotropic 4f-shell and singly occupied magnetic orbital(π) of the nitronyl nitroxide.

关键词： magnetic coupling density functional theory rare earth ion gadolinium(Ⅲ) complexes yttrium(Ⅲ) complexes

Possible Effect of 30K Proteins in Embryonic Development of Silkworm Bombyx mori

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Acta Biochimica et Biophysica Sinica 2005年第5期37卷 355-361页

作者： Bo-Xiong ZHONG~1 Jian-Ke LI~(1.2) Jian-Rong LIN~3 Jian-She LIANG~4 Song-Kun SU~1 Hai-Sheng XU~1 Hai-Yan YAN~1 Ping-Bo ZHANG~5 Hiroshi FUJII~5 1 Laboratory of Molecular Biology of Silkworm and Honeybee, Department of Bioresource science, college of animal science,Zhejiang university, Hangzhau 310029, china 2 Institute of Apicultural Research, Chinese Academy of agricultural science, beijing 100093, china 3 Department of Sericulture, South china agricultural university.Guangzhou 510642, china 4 Biochemistry Co. Ltd. of Zhejiang university, Hangzhou 310029. china 5 Faculty of Agriculture,Kyushu university, Fukuoka 812-81. Japan Laboratory of Molecular Biology of Silkworm and Honeybee Department of Bioresource Science College of Animal Science Zhejiang UniversityHangzhou 310029 China Institute of Agicultural Research Chinese Academy of Agricultural ScienceBeijing 100093 China Department of Sericulture South China Agricultural UniversityGuangzhou 510642 China Biochemistry Co. Ltd. of Zhejiang universityHangzhou 310029 China Faculty of Agriculture Kyushu UniversityFukuoka 812-81 Japan

The silkworm Bombyx mori possesses a 30K protein family of 3×10～4 Da,the biologicalfunctions of which have not been fully *** relationship between the 30K protein family and theembryonic development of temperature sensitive sex-linked mutant strain of silkworm was investigated bytwo dimensional polyacrylamide gel electrophoresis(2D-PAGE)and Matrix assisted laser desorption ionization-time of flight mass spectrometry(MALDI-TOF MS).The results show that protein spots 1-5 of the 30Kprotein family,mainly existing in normal strain,are possibly related to embryonic *** earlyconsumption of a 30K protein named 6G1-30K-1 and the accumulation of 30K proteins named 6G1-30K-3and 6G1-30K-4 are likely caused by the destruction of physiological balance in normal embryonic development,which may lead to lower hatchability of the temperature sensitive *** results suggest that reasonablemetabolism of 30K proteins is a prerequisite for the embryo's normal development.

关键词： silkworm Bombyx mori 30K protein embryonic development 2D-PAGE MALDI-TOF MS

Complex variable method for plane elasticity of icosahedral quasicrystals and elliptic notch problem

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science china(Physics,Mechanics & Astronomy) 2008年第7期51卷 773-780页

作者： LI LianHe1,2 & FAN TianYou1 1 Department of Physics, beijing Institute of technology, beijing 100081, china 2 college of Mathematics science, Inner Mongolia Normal university, Hohhot 010022, china Department of Physics Beijing Institute of Technology Beijing China college of Mathematics science Inner Mongolia Normal University Hohhot China

The complex variable method for the plane elasticity theory of icosahedral quasicrystals is developed. Based on the general solution obtained previously, complex representations of stress and displacement components of phonon and phason fields in the quasicrystals are given. With the help of conformal transformation, an analytic solution for the elliptic notch problem of the material is presented. The solution of the Griffith crack problem can be observed as a special case of the results. The stress intensity factor and energy release rate of the crack are also obtained.

关键词： icosahedral quasicrystals plane elasticity elliptic notch complex variable method

Arbitrarily long distance quantum communication using inspection and power insertion

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Chinese science Bulletin 2009年第1期54卷 158-162页

作者： WANG WanYing1,2,WANG Chuan1,2,ZHANG GuangYu1,3 & LONG GuiLu1,2 1 Department of Physics,Tsinghua university,beijing 100084,china 2 Tsinghua National Laboratory for Information science and technology,Tsinghua university,beijing 100084,china 3 college of Applied science,Harbin university of science and technology,Harbin 150080,china Department of Physics Tsinghua University Beijing China Tsinghua National Laboratory for Information science and technology Tsinghua University Beijing China college of Applied science Harbin University of Science and Technology Beijing China

The biggest obstacle for long distance quantum communication is the channel loss and the channel noise on photons. In this paper,a method to solve this problem was analyzed using inspection and power insertion (IPI). It is proved that quantum communication may be established over arbitrarily long distance using this technology. The amount of resources required is a polynomial function of the dis-tance. IPI is proposed as a general technique to prolong quantum secure direct communication where secret messages are transmitted directly over a quantum channel.

关键词：长距离量子通信量子安全通信量子密匙分布噪声

Preparation and Gas Permeation of Supported γ-Al_2O_3 Membranes Used as Substrate Layer for Microporous Membranes

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Journal of Wuhan university of technology(Materials science) 2005年第3期20卷 27-30页

作者：韦奇 Department of Materials science & Engineering University of Science & Technology of China college of Materials science & Engineering Beijing University of Technology Beijing 100022China

γ-Al2O3 membranes were successfidly deposited on the top of porous α-Al2O3 support by sol-gel process and characterized by means of XRD , SEM, N2 adsorption and gas permeation. The γ-Al2O3 membranes, free of pin-holes and cracks, adhere tightly to the supports and have a thlekness of about 7μm. When sintered at 400 ℃ , γ-Al2O3 membranes have a rutrrow pore size distribution, with a pore diameter of 3.6nm, and the transport of both H2 and CO2 in supported γ-Al2O3 membrane is governed by Knudsen mechanism, with H2 permeance of 3.3× 10^-6 molm^-2Pa^-1s^-1 and H2/ CO2 permselectivity close to the ideal Knudsen value at 50 ℃ . The γ-Al2O3 membranes are suitable for being used as the substrates of microparoas membranes .

关键词： supported γ-Al2O3 membranes hydrogen separation gas transport

3D building modeling,organization and application in digital city system

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中国科学：技术科学英文版 2010年第S1期53卷 134-142页

作者： YANG Xue 1,WENG JingNong 1,2,XIA YuBin 2,WU Lun 3 & SUI ZhengWei 3 1 college of Software,Beihang university,beijing 100191,china 2 college of Computer,Beihang university,beijing 100191,china 3 Institute of Remote Sensing and GIS,Peking university,beijing 100871,china college of Software Beihang University Beijing China college of Computer Beihang University Beijing China Institute of Remote Sensing and GIS Peking University Beijing China

The real world is a three-dimensional(3D)space requiring that 3D geospatial information applications be developed in alignment with the observer’s visual and perceptive ***,3D building model data are required in a wide range of areas such as urban planning,environmental protection,real estate management and emergency *** the same time,the development of Web service[LU1]technologies allows the possibility of the widely distributed 3D geospatial data on the web.3D city building model with its related information is an important part in the construction of a digital city system,and has become a staple resource on the web *** view of the hierarchical representation of a 3D building model,an abstract of a 3D building model based on structure details is studied,and a novel representation approach named 3D transparent building hierarchical model is presented in this *** approach fully uses both the existing 3D modeling technologies and CAD constructing mapping *** the spatial relationship description,structural components inside a building can be represented and integrated as hierarchical models in a unified 3D *** addition,based on the characteristics of the 3D building model data,a service-oriented architecture and Web service technologies for 3D city building models are *** aim of the approach is that 3D city building models can be used as a kind of data resource service on the web,and can also exist independently in various different web applications.

关键词： 3D modeling 3D transparent building hierarchical models china Star web services