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Two-dimensional simulation of Poiseuille-Rayleigh-Bénard flows in binary fluids with Soret effect

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Progress in Natural Science:Materials International 2007年第12期17卷 1389-1396页

作者： Hu Jun1.and Yin Xieyuan2(1. Institute of Applied Physics and Computational Mathematics, beijing 1.0088,{1. 2. Department of Modern Mechanics, university of Science and Technology of{1., Hefei 230027,{1.) Institute of Applied Physics and Computational Mathematics Beijing 100088 China Department of Modern Mechanics University of Science and Technology of China Hefei 230027 China

Poiseuille-Rayleigh-Bénard flows in binary fluids with Soret effect are directly simulated by a mixed finite element method. A temperature perturbation is used as an initial disturbed source for the basic parallel flows. The whole spatio-temporal evolution of the binary fluid flows is exhibited: initially only the disturbed mode with the wavenumber k=π is amplified while others are damped, and continuously the amplified mode grows further and the nonlinear effect becomes important; after a nonlinear evolution transition the flow system evolves finally into a periodic right traveling wave.

关键词： Poiseuille-Rayleigh-Bénard flow Soret effect through-flow.

Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural Science:Materials International 2007年第10期17卷 1127-1135页

作者： Song Nanmeng1. Sang Jianli1.and Xu Heng2(1. Institute of Cell Biology, College of Life Science, beijing Normal {1., beijing 1.0875, china 2. Emory {1. School of Medicine, GA 30332, USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875 China School of Medicine Emory University GA 30332 United States

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.

Structure and kinematic analysis of a novel 2-DOF translational parallel robot

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Progress in Natural Science:Materials International 2007年第10期17卷 1213-1219页

作者： Chen Tao1. Wu Chao2 and Liu Xinjun2(1. School of Application Science and Technology, Harbin university of Science and Technology, Harbin 1.0080,{1. 2. Department of Precision Instruments, Tsinghua university, beijing 1.0084,{1.) School of Application Science and Technology Harbin University of Science and Technology Harbin 150080 China Department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2 translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.

Protective Effects of Vitamin E against Oxidative Damage Induced by Aβ(1.40)Cu(Ⅱ)Complexes

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 123-130页

作者： Xueling DAI~1.Yaxuan SUN~2 and Zhaofeng JIANG~2 ~1.ollege of Life Science,Capital Normal university,Bejing 1.0037,{1. ~2College of Applied Sciences Humanities of beijing Union university,beijing 1.0083,{1. College of Life Science Capital Normal UniversityBeijing 100037 China College of Applied Sciences and Humanities of beijing Union {1.beijing 1.0083 China

β-amyloid peptide （Aβ） is considered to be responsible for the formation of senile plaques,which is the hallmark of Alzheimer's disease （AD）.Oxidative stress,manifested by protein oxidation andlipid peroxidation,among other alterations,is a characteristic of AD brain.A growing body of evidence hasbeen presented in support of Aβ1.40forming an oligomeric complex that binds copper at a CuZn superoxidedismutase-like binding site. Aβ1.40Cu（Ⅱ） complexes generate neurotoxic hydrogen peroxide （H2O2） from O2via Cue+ reduction,though the precise reaction mechanism is *** toxicity of Aβ1.40or the Aβ1.40Cu（Ⅱ）complexes to cultured primary cortical neurons was partially attenuated when （+）-α-tocopherol （vitamin E）as free radical antioxidant was added at a concentration of 1.0 μ*** data derived from lactate dehydro-genase （LDH） release and the formation of H2O2confirmed the results from the MTT *** findingsindicate that copper binding to Aβ1.40can give rise to greater production of H2O2, which leads to a break-down in the integrity of the plasma membrane and subsequent neuronal *** treated with vitaminE exhibited much slighter damage,suggesting that vitamin E plays a key role in protecting neuronal cellsfrom dysfunction or death.

关键词： Aβ1.40Cu(II)complex vitamin E neuronal oxidative damage H2O2 generation lactate dehydrogenase(LDH)release

Wave tectono-sedimentary processes in Tarim basin

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Science china Earth Sciences 2005年第11期48卷 1949-1959页

作者： JIN Zhijun1.2, ZHANG Yiwei1.& CHEN Shuping1.1. Key Laboratory for Hydrocarbon Accumulation, Ministry of Education, china {1. of Petroleum, beijing 1.2249, china 2. Exploration and Production Research Institute, china Petroleum & Chemical Corporation, beijing 1.0083, china Key Laboratory for Hydrocarbon Accumulation Ministry of Education China University of Petroleum Beijing China Exploration and Production Research Institute China Petroleum & Chemical Corporation Beijing China

Based on the unconformities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. The results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was controlled by various wave processes with the periods of 740±Ma, 200±Ma, 1.0±Ma and 30±Ma. The analyses of basin fills, basin subsidence and unconformities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 200±Ma. These show the propagation of wave movements in space domain. The wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

关键词： Tarim basin, tectonics, sedimentation, crustal undation, wave evolution

Weight hierarchies of linear codes satisfying the Near-Chain condition

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Progress in Natural Science:Materials International 2005年第9期15卷 784-792页

作者： LIU Zihui1.* and CHEN Wende2(1. School of Mathematical Sciences, Peking university, {1. 1.0871. china 2. Laboratory of Systems and Control and Key State Laboratory of Information Security, Institute of Systems Science, Academy of Mathematics and Systems Science, Chinese Academy of Sciences, {1. 1.0080, china) School of Mathematical Sciences Peking University Beijing 100871 China Laboratory of Systems and Control and Key State Laboratory of Information Security Institute of Systems Science Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100080 China

The weight hierarchies of a linear [n,k;q] code C satisfying the Near-Chain condition are studied, almost all the weight hierarchies of such code are determined.

关键词： weight hierarchy Near-Chain condition difference sequence linear code.

The correspondence between the concepts in description logics for contexts and formal concept analysis

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Science china(Information Sciences) 2012年第5期55卷 1106-1122页

作者： MA Yue 1.2,SUI YueFei 1.& CAO CunGen 1.1.Key Laboratory of Intelligent Information Processing,Institute of Computing Technology,Chinese Academy of Sciences,beijing 1.01.0,{1. 2 graduate university of Chinese Academy of Sciences,beijing,{1. Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing China graduate {1. of Chinese Academy of Sciences Beijing China

Formal concept analysis (FCA) and description logic (DL) are meant to be formalizations of concepts.A formal concept in the former consists of its intent and extent,where the intent is the set of all the attributes shared by each object in the extent of the concept,and the extent is the set of all the objects sharing each property in the intent of the concept.A concept in the latter formalization is simply a concept name,the interpretation of which is a subset of a *** consider the correspondence between concepts in both formalizations,a multi-valued formal context must be represented both as a knowledge base and as a model of the DL for contexts,where concepts are decomposed into tuple concepts C,interpreted as a set of tuples and value concepts V,interpreted as a set of attribute-value *** show that there is a difference between the interpretation of concepts R.V /R.C and the Galois connection between the extent/intent of formal concepts in *** to the Galois connection,there should be concepts of the form + R.V and + R.C inter-preted in FCA,and hence the logical language L for DL is extended to be L + together with + as a constructor so that + R.V and + R.C are well-defined ***,according to the interpretation in DL there should be pseudo concepts in FCA so that the interpretation of concepts R.V /R.C is the extent/intent of pseudo *** correspondence between formal concepts and concepts in L +,and between pseudo concepts and concepts in L are presented in this paper.

关键词： description logic formal concept analysis concept attribute/role

Electroluminescent properties of three ternary europium complexes with different phenanthroline derivatives

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Science china Chemistry 2004年第4期47卷 326-334页

作者： BIAN Zuqiang1.2, GAO Deqing1. GUAN Min1. XIN Hao1. LI Fuyou1. HUANG Chunhui1. WANG Kezhi2 & JIN Linpei2 1. State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking university, {1. 1.0871. china 2. Department of Chemistry, {1. Normal university, {1. 1.0875, china State Key Laboratory of Rare Earth Materials Chemistry and Applications Peking University Beijing China Department of Chemistry Beijing Normal University Beijing China

Three ternary Eu(III) complexes with general formula of Eu(DBM)3LN (DBM = dibenzoylmethanate, and LN (N = 1.3 ) stand for three different 1.1.-phenanthroline derivatives) have been synthesized for vacuum deposition films-based electroluminescent devices. The complex Eu(DBM)3L3 (L3 = 2-phenyl-3-[3-(carbazol-9-yl)propyl]imidazo[4,5-f]1.1.-phenan-throline) was designed with an effort to combine the electron-transporting phenanthroline platform and the hole-transporting carbazole group into one molecule expecting to improve both electron and hole transporting properties simultaneously. The results show that the variation of the neutral ligands in Eu(III) mixed ligand complexes is a simple and effective approach to the improvement in the thermal stability, PL and EL properties of materials. A double-layer device with the configuration of ITO/TPD (50 nm)/Eu(DBM)3L3 (50 nm)/Mg0.9Ag0.1.(200 nm)/Ag (1.0 nm) exhibited Eu(III)-based pure red emission with a maximum brightness of 561.cd/m2 at 1. V, and an onset driving voltage of 8 V. A device with the configuration of ITO/TPD (50 nm)/[Eu(DBM)3L3 (5 nm):BCP (5 nm)]4/BCP (20 nm)/AIQ (1. nm) Mg0.9Ag0.9 (1.0 nm)/Ag (1.0 nm) gave high efficient and pure red light emission with a luminance of 1.1. cd/m2. Keywords dibenzoylmethane - electroluminescence - lanthanide - N ligands

关键词： dibenzoylmethane electroluminescence lanthanide N ligands

Testing local realism in P → VV decays

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Science china(Physics,Mechanics & Astronomy) 2010年第5期53卷 870-875页

作者： LI JunLi1.& QIAO CongFeng1.2 1.epartment of Physics,graduate {1. of Chinese Academy of Sciences,beijing 1.0049,china 2Theoretical Physics Center for Science Facilities(TPCSF),Chinese Academy of Sciences,beijing 1.0049,china Department of Physics Graduate University of Chinese Academy of Sciences Beijing China Theoretical Physics Center for Science Facilities (TPCSF) Chinese Academy of Sciences Beijing China

It was found that the vector meson pair from the pseudoscalar decays can form an entangled *** this work we give out detailed explanations on the polarization correlation of the two entangled vector *** is demonstrated that an experimental test of the Clauser-Horne inequality can be carried out through measuring the azimuthal distribution of four pseudoscalars in the cascade decay ηc→ VV →(PP)(PP),and the measurement of this process is feasible with the current running experiments in tau-charm ***,a brief discussion on the polarization correlation of the two vector mesons from B → VV decays is also presented.

关键词： nonlocality test high energy experiment meson decays