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

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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 2.0072.{2. 2.shanghai institute of applied Mathematics and Mechanics,shanghai University,shanghai 2.0072. china 3 institute of Geotechnical Engineering,shanghai Jiao Tong University,shanghai 2.0030,{2. 4 institute of Rock and Soil Mechanics,chinese academy of sciences,Wuhan 430071,{2. 1. Department of Civil Engineering Shanghai University Shanghai 200072 China 2. shanghai institute of {2. 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

On some tests-based projection pursuit for elliptical symmetry of a high-dimensional distribution

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chinese Science Bulletin 1998年第6期43卷 450-458页

作者： JING Ping 1 and ZHU Lixing 2.1. Mathematics Lab, china University of Mining & Technology, Beijing 100083, china 2. Probability Lab, {2. of applied Mathematics, chinese academy of sciences, Beijing 100080, china Mathematics Lab China University of Mining & Technology Beijing China Probability Lab Institute of Applied Mathematics Chinese Academy of Sciences Beijing China

Some test statistics of Kolmogorov type and Cramér-von Mises type based on projection pursuit technique are proposed for the testing problem of sphericity of a high-dimensional distribution. The limiting distributions of the test statistics are derived under the null hypothesis and under any fixed alternative. The asymptotic properties of bootstrap approximation are investigated. Furthermore, for computational reasons, an approximation for the statistics, based on the number theoretic method, is suggested.

关键词： bootstrap approximation projection pursuit type statistic elliptical symmetry.

Simulation on C/A codes and analysis of GPS/pseudolite signals acquisition

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Science china(Technological sciences) 2009年第5期52卷 1459-1462页

作者： ZHANG Lei shanghai institute of Technical Physics,{2. academy of sciences,shanghai 2.0083,china shanghai institute of Technical Physics Chinese Academy of Sciences Shanghai 200083 China

The global positioning system(GPS) is an extremely mature technique in the navigation and position-ing ***,there are still some limits in some aspects and for some special ***-cially,the performance of GPS needs to be improved with technological *** a GPS-like ground transmitter,the pseudolite provides a new research direction to achieve high positioning ac-curacy and *** this paper,we describe the core technologies of designing and simulation on the coarse acquisition codes in constructing the pseudolite *** the GPS/pseudolite integration system,the signal PRN 36 of the pseudolite and the GPS satellites signals are acquired in the modified receiver based on the computer software *** is shown that the pseudolite technology is ideally suited to augment the GPS alone and provide greater integrity,availability,and continuity of the navi-gation positioning system,especially for indoor use.

关键词： GPS pseudolite coarse acquisition(C/A) code acquisition

Organic Solvents Mediate Self-assembly of GAV-9 Peptide on Mica Surface

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Acta Biochimica et Biophysica Sinica 2007年第4期39卷 285-289页

作者： Hai LI~(1,3) Feng ZHANG~1 Yi ZHANG~1* Jianhua HE~1 Jun HU~(1,2. 1 shanghai institute of {2. Physics,chinese academy of sciences,shanghai 2.1800,china 2.Bio-X Life sciences Research Center.College of Life Science and Biotechnology,shanghai Jiaotong University,shanghai 2.0030,china 3 Graduate School of the chinese academy of sciences,Beijing 100049,china shanghai institute of {2. Physics Chinese Academy of SciencesShanghai 201800 China Graduate School of the chinese academy of sciencesBeijing 100049 China Bio-X Life sciences Research Center College of Life Science and Biotechnology Shanghai Jiaotong UniversityShanghai 200030 China

Self-assembly of peptides into fibrils and other morphologies has attracted much attention inmany fields,especially in nanofabrication,pathology and *** this paper,self-assembly of GAV-9peptide in organic solvents,ethanol and acetone,was investigated using atomic force microscopy(AFM)and attenuated total reflectance-Fourier transform infrared spectroscopy(ATR-FTIR).The results indicatedthat GAV-9 self-assembled into various nanostructures in both solvents after deposited and evaporated *** with β-sheet conformation were observed in both solvents when the peptide concentrationwas higher than 2.0 μ***,ordered fibrils with β-sheet conformation were formed in ethanol,butnot in acetone,with a peptide concentration ranging from 7 μM to 2. μ*** attribute the formation ofvarious nanostructures to the different physicochemical properties of the polar organic solvents on the self-assembly of GAV-9 peptide.

关键词： self-assembly GAV-9 peptide organic solvents ATR-FTIR AFM

Conus Peptides-A Rich Pharmaceutical Treasure

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Acta Biochimica et Biophysica Sinica 2004年第11期36卷 713-723页

作者： Cheng-Zhong WANG and Cheng-Wu CHIinstitute of Biochemistry and Cell Biology, shanghai institute of Biological sciences, the chinese academy of sciences, shanghai 2.0031, china institute of Neuroscience, the chinese academy of sciences, shanghai 2.0031, china institute of Protein Research, Tongji University, shanghai 2.0092. china institute of Biochemistry and Cell Biology Shanghai Institute of Biological Sciences the Chinese Academy of Sciences institute of Neuroscience the Chinese Academy of Science institute of Protein Research Tongji University

Marine predatory cone snails (genus Conus) with over 500 species represent what is arguably the largest single genus of marine animals alive today. All Conus are venomous and utilize a complex mixture of Conus peptide... 详细信息

关键词： Conus peptide conotoxin neuropathic disorder pharmaceutical potency

The Role of Propeptide in the Refolding of Human Group IB Phospholipase A2

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 583-588页

作者： Hong-Qiang CHENG1 and Gen-Jun XU1,2.institute of Biochemistry and Cell Biology, shanghai institutes for Biological sciences, chinese academy of sciences, shanghai 2.0031, china 2.ollege of Life Science, Zhejiang University of sciences, Hangzhou 310033, china institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences College of Life Science Zhejiang University of Sciences

Human group IB phospholipase A2.(IB-PLA2. and its zymogen (proIB-PLA2. were purified from E. coli. Refolding was carried out by diluting the denatured forms of both IB-PLA2.and proIB-PLA2. with renaturation buffer in which the disulfide bonds were completely reduced. The refolding yield of proIB-PLA2.was increased by about 50% over that of the mature enzyme. The refolding of IB-PLA2.usually produced aggregates under normal conditions, as determined by light scattering. In addition, the unfolding experiments showed that the mature enzyme was more stable than the proenzyme toward denaturants in the presence of DTT. Results suggested that the N-terminal sequence rather than its conformation of human proIB-PLA2.played an important role in the refolding process.

关键词： human group IB phospholipase A2.(IB-PLA2. refolding first disulfide bond propeptide

Formation and Oxidation Resistance of Silicide Coatings for Mo and Mo-Based Alloys

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Journal of Materials Science & Technology 2001年第4期17卷 479-481页

作者： Yu WANG , Yunpeng LI and Xingfang HU shanghai institute of Ceramics,{2., shanghai 2.0050, china chinese Acad Sci Shanghai Inst Ceram Shanghai 200050 Peoples R China

The forming process of silicide coatings on pure Mo and Mo-base alloys, obtained by the gas- phase deposition method. has been studied by examining the microstructure of coatings and the relationship between coating thickness and process parameters. It was shown that the growth of coatings was diffusion-controlled, the diffusion of silicon to be coated into Mo or Mo-base alloys was mainly responsible for the formation of silicide. The relationship between initial silicide thickness and oxidation resistance was also investigated, and the equation of service life of the coatings at high temperature in air is presented.

关键词： Mo Formation and Oxidation Resistance of Silicide Coatings for Mo and Mo-Based Alloys

Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science china Chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. Chemistry and Chemical Engineering College of Henan University, Kaifeng 475001, china 2. Changchun institute of {2. Chemistry, chinese academy of sciences, Changchun 13002., china 1. Chemistry and Chemical Engineering College of Henan University Kaifeng 475001 China 2. Changchun institute of applied Chemistry Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

Two-dimensional Riemann problems of simplified Euler equation

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chinese Science Bulletin 1998年第6期43卷 441-444页

作者： YANG Xiaozhou 1,2.and HUANG Feimin+1 1. institute of applied Mathematics,{2., Beijing 100080, china 2. Department of Mathematics, Shantou University, Guangdong 515063, china institute of applied Mathematics Chinese Academy of Sciences Beijing China Department of Mathematics Shantou University Guangdong China

The two-dimensional Riemann problem of simplifed Euler equation is discussed, in which initial value contains two different constant states that are separated by a smooth curve. This problem is a natural description of realistic phenomena, but it is hard to study by conventional idea. So a new approach is proposed. Some new properties about two-dimensional rarefaction wave, shock wave and intermediate state of solutions are disclosed.

关键词： D Riemann problem implicit functions cylindrical surface pencil of cylindrical surface.