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Virtual multi-dimensional internal bonds model and its application in simulation of rock mass

Science china(Technological Sciences) 2008年第2期51卷 192-201页

作者： ZHANG ZhenNan1,2 & GE XiuRun3.4 1 Department of Civil Engineering,shanghai university,shanghai 200072,{3. 2 shanghai Institute of Applied Mathematics and Mechanics,shanghai university,shanghai 200072, {3. 3.Institute of Geotechnical Engineering,shanghai Jiao Tong university,shanghai 20003.,{3. 4 Institute of Rock and Soil Mechanics,{13. academy of Sciences,Wuhan 43.071,{3. 1. Department of Civil Engineering Shanghai University Shanghai 200072 China 2. shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China 3. Institute of Geotechnical Engineering Shanghai Jiao Tong University Shanghai 200030 China 4. Institute of Rock and Soil Mechanics Chinese Academy of Sciences Wuhan 430071 China

VMIB (virtual multi-dimensional internal bonds) is a multiscale mechanical model developed from the VIB (virtual internal bond) theory. In VIB theory,the solid mate-rial is considered to consist of random-distributed material particles in microscale. These particles are connected with normal bonds. The macro constitutive relation is derived from the cohesive law between particles. However,in VMIB,the micro particles are connected with both normal and shear bonds. The macro constitutive relation is derived in terms of bond stiffness coefficients. It has been theoretically certified that there exists a corresponding relationship between the two bond stiffness coefficients and the two macro material constants,i.e. the Young’s modulus and Poisson ratio. This corresponding relationship suggests that it should be necessary and sufficient to simultaneously account for the normal and shear interactions between particles. Due to the fact that the fracture criterion is directly incorporated into the constitutive relation,both VIB and VMIB present many advantages in simulating fractures of materials. In the damage model of rock mass,a damage tensor is usually defined to describe the distribution of cracks. The damage value in one direction determines the relative stiffness of rock mass in this direction. In VMIB solid,the relative distribution density of micro bonds in one direction determines the relative macro stiffness of the material in this direction. The effects of the damage value and the relative distribution density of bonds are consistent. To simulate the failure behavior of rock mass with VMIB,the presented paper sets up a quantitative relationship between the damage tensor and the rela-tive distribution density of bonds. Comparison of the theoretical and the experi-mental results shows that VMIB model can represent the effect of distributed cracks on rock mass with this relationship. The presented work provides a founda-tion for further simulating fracture behavior

关键词： VMIB (virtual multi-dimensional internal bonds) rock mass VIB (virtual internal bonds) multi-cracked body numerical simulation

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Transverse patterns and spatiotemporal instability of a photorefractive oscillator

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chinese Science Bulletin 1997年第9期42卷 724-729页

作者： ZHUANG Jun and TAN Weihan1. shanghai Institute of Optics and Fine Mechanics, chinese academy of Sciences, shanghai 201800, china 2. shanghai university, shanghai 201800, china shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai China shanghai university Shanghai China

IN time realm,instability and chaos phenomena of a nonlinear optical system have been dis-cussed *** recent years,as much interest was attracted to the transverse ef-fects in nonlinear optics,the study was developed t... 详细信息

关键词： photorefractive oscillator spatiotemporal instability transverse patterns.

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Impact Assessment and Protection of Outstanding Landscape Integrity in a Natural Heritage Site:Fairy Valley,Kanas Nature Reserve,Xinjiang,china

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Journal of Mountain Science 2011年第1期8卷 46-52页

作者： HAN Fang1,2,YANG Zhaoping1,LIU Xinyu1,2,DI Feng3.1 Xinjiang Institute of Ecology and Geography,chinese academy of Sciences,Urumqi 83.011,china 2 {3. university of chinese academy of Sciences,Beijing 100049,china 3.Xinjiang Department of Science and Technology,Urumqi 83.011,china Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi China graduate university of chinese {3. of Sciences Beijing China Xinjiang Department of Science and Technology Urumqi China

The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage *** landscape is the core embodiment of the aesthetic value of a natural heritage *** paper proposes a new assessment method from the point of view of the protection of heritage *** is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage *** paper employ three indices,a visual index of outstanding landscape,a harmony index of the artificial landscape and a disturbance index of damaged landscape,to measure the impact of landscape *** impact assessment model is based on a weighted combination of the three *** study site is the Fairy Valley,Kanas Nature Reserve,Xinjiang Uygur Autonomous Region in northwest *** information employed is derived from field investigation and a Digital Elevation Model(DEM).A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being *** protection methods are proposed to reduce the adverse effects and maintain landscape quality,thereby providing site managers with suggestions for the protection of natural heritage *** broadly,the paper contributes novel methods of landscape assessment applicable to natural protected areas.

关键词： Landscape integrity Landscape impact assessment Landscape protection Natural heritage site Kanas Nature Reserve Xinjiang

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Narrow line Seyfert 1 galaxies: where are the broad line regions?

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Science china(Physics,Mechanics & Astronomy) 2010年第12期53卷 2307-2311,2339-2343页

作者： MAO WeiMing 1,2,3., HU Chen 2 , WANG JianMin 2 , BIAN WeiHao 4 , ZHANG Shu 2 & ZHAO Gang 1 1 Key Laboratory of Optical Astronomy, National Astronomical Observatories, chinese academy of Sciences, Beijing 100012, china 2 Key Laboratory for Particle Astrophysics, Institute of High Energy Physics, chinese academy of Sciences, Beijing 100049, china 3.graduate university of the chinese academy of Sciences, Beijing 100049, china 4 Department of Physics, Nanjing Normal university, Nanjing 210011, china 1. Key Laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China4. Department of Physics Nanjing Normal University Nanjing 210011 China

A sample consisting of 211 narrow line Seyfert 1 galaxies (NLS1s) with high quality spectra from the Sloan Digital Sky Survey (SDSS) is selected to explore where broad line regions are in these objects. We find that the Hβ profile can be fitted well by three (narrow, intermediate and broad) Gaussian components, and the FWHM ratios of the broad to the intermediate components hold a constant of 3.0 roughly for the entire sample. If the broad components originate from the region scaled by the well-determined Hβ reverberation mapping relation, we find that the intermediate components originate from the inner edge of the torus, which is scaled by dust K-band reverberation. We find that the IC and the BC are strongly linked dynamically, but the relation of their covering factors is much more relaxed, implying that both regions are clumpy.

关键词： black hole physics galaxies: evolution quasars: general

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Positive Charges on Lysine Residues of the Extrinsic 18 kDa Protein Are Important to Its Electrostatic Interaction with Spinach Photosystem Ⅱ Membranes

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Acta Biochimica et Biophysica Sinica 2005年第11期37卷 737-742页

作者： Jin-Peng GAO Zhen-Hua YONG Feng ZHANG Kang-Cheng RUAN Chun-He XU Gen-Yun CHEN Institute of Plant Physiology & Ecology.shanghai Institutes for Biological Sciences,chinese academy of Sciences,{3.,china Laboratory of Proteomics,Institute of Biochemistry and Cell Biology,shanghai Institutes for Biological Sciences,chinese academy of Sciences,{3.,china College of Sciences,Zhejiang university.Hangzhou 3.0029,china graduate School of the chinese academy of Sciences,{3.,china Institute of Plant Physiology & Ecology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200032 China graduate School of the chinese academy of Sciences{3. China College of Sciences Zhejiang UniversityHangzhou 310029 China Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China

To determine the contribution of charged amino acids to binding with the photosystem Ⅱcomplex(PSⅡ),the amino or carboxyl groups of the extrinsic 18 kDa protein were modified with N-succinimidyl propionate(NSP)or glycine methyl ester(GME)in the presence of a water-soluble carbodiimide,*** on isoelectric point shift,4-10 and 10-14 amino groups were modified in the presence of2 and 4 mM NSP,***,3.4 carboxyl groups were modified by reaction with *** of negatively charged carboxyl groups with GME did not alter the binding activity of theextrinsic 18 kDa ***,the NSP-modified 18 kDa protein,in which the positively charged aminogroups had been modified to uncharged methyl esters,failed to bind with the PSⅡ membrane in the presenceof the extrinsic 23.kDa *** defect can not be attributed to structural or conformational alterationsimposed by chemical modification,as the fluorescence and circular dichroism spectra among native,GME-and NSP-modified extrinsic 18 kDa proteins were ***,we have concluded that the positive chargesof lysyl residues in the extrinsic 18 kDa protein are important for its interaction with PSⅡ membranes in thepresence of the extrinsic 23.kDa ***,it was found that the negative charges of carboxylgroups of this protein did not participate in binding with the extrinsic 23.kDa protein associated with PSⅡmembranes.

关键词： extrinsic 18 kDa protein circular dichroism electrostatic interaction chemical modification

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Identification and Characterization of hmr19 Gene Encoding a Multidrug Resistance Efflux Protein from Streptomyces hygroscopicus *** Strain 10-22

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 519-528页

作者： Lei QIN , Heng-An WANG1 , Zhong-Qin WU, Xiao-Feng ZHANG, Mei-Lei JIN,Zi-Xin DENG2, and Guo-Ping ZHAOshanghaiResearch Center of Biotechnology, shanghai Institute for Biological Sciences, chinese {3. of Sciences,graduate School of the chinese {3. of Sciences, shanghai 20023., china 1School of Agriculture and Biology, shanghai Jiaotong university, shanghai 201101, china 2School of Life Science and Biotechnology, shanghai Jiaotong university, shanghai 20003., china shanghaiResearch Center of Biotechnology Shanghai Institute for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences School of Agriculture and Biology Shanghai Jiaotong University

The hmr19 gene was cloned from Streptomyces hygroscopicus subsp. yingchengensis strain 10- 22, a bacterium strain producing agricultural antibiotics. Sequence similarity comparison indicates that hmr19 gene may encode a predicted protein with 14 putative transmembrane α-helical spanners, belonging to the drug:H+ antiporter-2 family of the major facilitator superfamily. The expression of hmr19 in the mycelium of strain 10-22 was detected by Western blotting analysis. Gene replacement technology was employed to construct an hmr19 disruption mutant. The growth inhibition test against different antibiotics indicated that the mutant strain was 5–20 fold more susceptible to tetracycline, vancomycin and mitomycin C than the parental wild type strain. The mutant took up tetracycline much faster and accumulated more antibiotics than the wild type strain 10-22. While with the addition of an energy uncoupler, carbonyl cyanide m- chlorophenylhydrazone, the characteristics of the accumulation of [3.]tetracycline in these two strains were almost the same. It was thus concluded that hmr19 encoded a multidrug resistance efflux protein.

关键词： multidrug resistance (MDR) gene replacement (knockout) Streptomyces Streptomyces hygroscopicus subsp. yingchengensis strain 10-22

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Application of the moist vorticity vector in the analysis of a heavy rainfall event in North china

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Progress in Natural Science:Materials International 2007年第12期17卷 1457-1465页

作者： Zhao Yu1,2,3. Wang Jianguo4 and Xue Deqiang2(1. Laboratory of Cloud-Precipitation Physics and Severe Storms, Institute of Atmospheric Physics, chinese academy of Sciences, Beijing 100029, china 2. Shandong Provincial Meteorological Observatory, Jinan 25003., china 3. graduate university of chinese academy of Sciences, Beijing 10003., china 4. Shandong Provincial Meteorological Bureau, Jinan 25003., china) Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Shandong Provincial Meteorological Observatory Jinan 250031 China graduate university of chinese {3. of Sciences Beijing 100039 China Shandong Provincial Meteorological Bureau Jinan 250031 China

The moist vorticity vector (MVV), defined as (ζa×▽qv)/ρ introduced by Gao et al. is used to study a heavy rainfall event in North china. The MVV has zonal, meridional and vertical components in a three-dimensional framework. Analysis of domain-mean and mass-integrated quantities shows that the variation of the vertical component of the MVV closely follows the variation of the cloud hydrometeors, with a linear correlation coefficient of 0.95, indicating that the vertical component of the MVV is strongly associated with midlatitude convection. Further analysis shows that the vertical component of the MVV reflects the interaction between the horizontal vorticity and the horizontal specific humidity gradient, which can associate dynamic and thermodynamic processes with cloud microphysical processes. Thus, this study can help to understand how the interaction between circulations and clouds aids the development of convection, and the MVV can be used to trace the development and evolution of heavy rainfall.

关键词： moist vorticity vector heavy rainfall modeling study.

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On conformal measures for infinitely renormalizable quadratic polynomials

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Science china Mathematics 2005年第10期48卷 1411-1420页

作者： HUANG Zhiyong~1 JIANG Yunping~(2,3. & WANG Yuefei~3.1. School of Information,Renmin university of china,Beijing 100872,china 2. Department of Mathematics,Queens College,City university of New York,NY 113.7,USA Department of Mathematics,graduate School,City university of New York,New York,NY 10016,USA 3. academy of Mathematics and Systems Science,chinese academy of Sciences,Beijing 100080,china 1. School of Information Renmin University of China 100872 Beijing China 2. Department of Mathematics Queens College City University of New York 11367 NY USA 3. Department of Mathematics Graduate School City University of New York 10016 New York NY USA 4. academy of Mathematics and Systems Science Chinese Academy of Sciences 100080 Beijing China

We study a conformal measure for an infinitely renormalizable quadratic polynomial. We prove that the conformal measure is ergodic if the polynomial is unbranched and has complex bounds. The main technique we use in t... 详细信息

关键词： Julia set, conformal measure, three-dimensional puzzle, infinitely renormalizable quadratic polynomial.

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Transient species and its properties of melatonin

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Science china Chemistry 2006年第4期49卷 308-314页

作者： ZHU Hongping1,2, ZHANG Zhaoxia1,2, ZHAO Hongwei1, WANG Wenfeng1 & YAO Side1 1. shanghai Institute of Applied Physics, chinese academy of Sciences, shanghai 201800, china 2. graduate university of the chinese academy of Sciences, Beijing 100049, china 1. shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 2. graduate university of the chinese {3. of Sciences Beijing 100049 China

The photo-physical and photo-chemical properties of melatonin (ML) werestudied by 266 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radicalcation of ML (ML^(·+))and hydrated electrons (e_(aq)^-), while excited triplet state ~3.L~* is alsoformed during photolysis. The oxidation via one electron transfer from ML to SO_4^(·+) and thetriplet state of riboflavin (~3.F~*) has been also investigated and the rate constants for theprocess have been determined to be 8.0x10^9 and 1.4x10^9 L·mol^(-1)·s^(-1) respectively. Theradical cation of 2,2''-azinobis(3.ethylbenzothiazoline-6-sulfonic acid)(ABTS^(·+)) scavengingcapacities of melatonin and other antioxidants are compared in this paper.

关键词： melatonin, laser flash photolysis, photoionization, triplet state.

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An H_2O flare in GGD25

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chinese Science Bulletin 2001年第1期46卷 35-39页

作者： XU Ye, ZHENG Xingwu JIANG Dongrong, ZHANG Fujun& YU Zhiyao1. shanghai Astronomical Observatory, chinese academy of Sciences, {3., china 2. chinese National Observatories, chinese academy of Sciences, Beijing 100080, china 3. Department of Astronomy, Nanjing university, Nanjing 210093. china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai China chinese National Observatories Chinese Academy of Sciences Beijing China Department of Astronomy Nanjing University 210093 China

We report the observing results of a short time scale monitoring of the 22 GHz water maser emission in GGD25. A rapid water maser outburst with the time scales of 4 d has been detected, and the variations are accompanied by some changes in the line width. The time variations were probably caused by a collision pump which led to changes in the pump input.

关键词： interstellar masers (ISM) individual GGD25 masers.

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