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Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science China Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research Center, Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 10002., China 2. department of Atmospheric Science, Yunnan {2., Kunming 650091, China 3. Graduate {2. of the Chinese Academy of Sciences, Beijing 100049, China 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate university of the Chinese Academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

DFT study of the conductance of molecular wire:The effect of coupling geometry and intermolecular interaction on the transport properties

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Science China Chemistry 2006年第6期49卷 492-498页

作者： QI Yuanhua1,2. GUAN Daren1 & LIU Chengbu1 1. Institute of Theoretical Chemistry, Shandong university, Jinan 2.0100, China 2. School of physics and Microelectronics, Shandong university, Jinan 2.0061, China 1. Institute of Theoretical Chemistry Shandong University Jinan 250100 China 2. School of physics and Microelectronics Shandong University Jinan 250061 China

The density functional theory (DFT) combining with the non-equilibrium Green functions (NEGF) method is applied to the study of the electronic transport properties for a Di-thiol-benzene (DTB) molecule coupled to two Au(111) surfaces. The dependence of the transport properties on the bias, the coupling geometry of the molecule-electrode interface, and the intermolecular interaction are examined in detail. The results show that the existence of the hydrogen atom at the end of the DTB molecule would significantly decrease the transmission coefficients, and then the differential conductance (dI/dV). By changing the position of the DTB molecule located between two electrodes a maximum value of calculated current is observed. It is also found that the intermolecular interaction will strongly influence the transport properties of the system studied.

关键词： non-equilibrium Green functions method, transmission spectrum, the molecular projected selfconsistent Hamiltonian, projected density of state.

Field-induced Magnetic Phase Transitions in FerrimagnetGdMn_2.e_2. H-T Magnetic Phase Diagrams

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Journal of Central South university 2000年第2期12卷 107-110页

作者： GUO Guang hua 1,R.Z. Levitin 2.N.P. Kolmakova 3 (1 department of applied {2. and Heat Energy Engineering, Central South university of Technology, changsha 410083, China 2.department of {2., M. V. Lomonosov Moscow State university, 1198 1. department of applied {2. and Heat Energy Engineering Central South University of Technology 410083 Changsha China 2. department of physics M. V. Lomonosov Moscow State University 119899 Moscow Russia 3. Bryansk State Technical university 241035 Bryansk Russia

Magnetic properties of a two sublattice ferrimagnet with antiferromagnetic exchange interaction inside one of the sublattices are calculated within the framework of the molecular field theory taking into account the anisotropy of unstable sublattice. The magnetization curves of single crystal GdMn 2.e 2.for the magnetic field parallel and perpendicular to the c axis at different temperatures are calculated. Field induced magnetic phase transitions in GdMn 2.e 2.are discussed. Calculated H T magnetic phase diagrams are in fair agreement with experimental data.

关键词： ferrimagnet magnetic phase transition rare earth intermetallics

Approaches to improving critical current density of YBCO superconducting thick films deposited by electrophoresis

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Science China(physics,Mechanics & Astronomy) 2004年第2期47卷 165-172页

作者： ZHU Yabin1,2. ZHOU Yueliang2. LIU Zhen2. WANG Shufang2. CHEN Zhenghao2. L?Huibin2. YANG Guozhen2. XIAO Ling3, REN Hongtao3, JIAO Yulei3 & ZHENG Minghui3 1. department of physics, College of Science, Beijing Jiaotong {2., Beijing 100044, China 2. Laboratory of Optical physics, Institute of physics and Center for Condensed Matter physics, Chinese Academy of Sciences, Beijing 100080, China 3. General Research Institute for Nonferrous Metals, Beijing 100088, China Correspondence should be addressed to Zhu Yabin (email: ybzhu@***) 1. department of physics College of Science Beijing Jiaotong University 100044 Beijing China 2. Laboratory of Optical physics Institute of physics and Center for Condensed Matter physics Chinese Academy of Sciences 100080 Beijing China 3. General Research Institute for Nonferrous Metals 100088 Beijing China

Fabrication of YBCO superconducting thick films by electrophoresis has been widely reported. However, the value of critical current density (J c) is far from what the practical application requires. The superconducting thick films are obtained using top-seeded melt growth method with different proportional Y2.aCuO5 (Y2.1) addition. High-pressure oxygen has been used in the annealing process to improve the uniformity of the oxygen content in the superconducting thick films. When 40mol% Y2.1 powder is added to the YBa2.u3O7–5 (Y12.) powder,J c for the superconducting thick film by approaches described above reaches 7.008×103 A/cm2.(77 K, 0 T), which is greater than the value ever reported.

关键词： YBCO thick films, electrophoretic deposition, melt-textured.

Modulation on the collective response behavior by the system size in two-dimensional coupled cell systems

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Science China(physics,Mechanics & Astronomy) 2006年第3期49卷 304-312页

作者： ZHANG Jiqian1, SHEN Chuansheng1,2.& CUI Zhifeng1 1. College of physics and Electronic Information, Anhui Normal university, Wuhu 2.1000, China 2. {2. of Educational Technology, Anqing Teachers College, Anqing 2.6011, China College of physics Electronic Information Anhui Normal University Wuhu 241000 China department of Educational Technology Anqing Teachers College Anqing 246011 China

By the intracellular calcium ionic minimal model proposed by Berridge, we investigated the collective response of two-dimensional (N×N) coupled cell systems to the external stimulation using numerical simulation methods. With a coupled intensity fixed and an appropriate coupled cell number chosen, the kinetic system size resonance was discovered. At the same time, it was found that the system size responding to the external stimulation for different coupled intensities transferred too, especially when the coupled intensity increased, the range of the corresponding system size extended. These phe- nomena illustrate that the coupled cell number and the coupled intensity can play con- structive roles in noisy coupled systems, by which the biology system would probably improve its capability to respond to the external stimulation.

关键词： cell coupling,collective response,system size resonance

Entropy product measure for multipartite pure states

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Science China(physics,Mechanics & Astronomy) 2006年第5期49卷 606-615页

作者： CAO Wancang1,2. LIU Dan2. PAN Feng3 & LONG Guilu2.4 1. department of physics, Chifeng College, Chifeng 02.001, China 2. Key Laboratory for Quantum Information and Measurements, department of physics, Tsinghua university, Beijing 100084, China 3. department of physics, Liaoning Normal university, Dalian 11602., China 4. Key Laboratory for Atomic and Molecular Nano-Sciences, Tsinghua university, Beijing 100084, China Correspondence should be addressed to Long Guilu department of physics Chifeng College Chifeng 024001 China Key Laboratory for Quantum Information Measurements Department of Physics Tsinghua University Beijing 100084 China department of physics Liaoning Normal University Dalian 116029 China Key Laboratory for Atomic Molecular Nano-Sciences Tsinghua University Beijing 100084 China

An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents. Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been compared with the result of ‘the average entropy’. The new measure can be used to calculate the degree of entanglement, and an improvement is given in the area near the zero entropy.

关键词： multipartite pure state von Neumann entropy entanglement measure

PERIODIC SOLUTIONS OF LINEAR NEUTRAL INTEGRO-DIFFERENTIAL EQUATIONS

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Acta Mathematica Scientia 2004年第3期24卷 337-348页

作者：马世旺王志成许强 department of Mathematics Shanghai Jiaotong University Shanghai 200030 China department of applied Mathematics Hunan University Changsha 410082 China x(t + s) + f(t)where x and / are ra-dimensional vectors A is an n x n constant matrix and L(s) is an n x n matrix function with bounded total variation. Some necessary and sufficient conditions are given which guarantee the existence and uniqueness of periodic solutions to the above equation.

Consider the linear neutral FDEd/dt[x(t) + Ax(t - r)] = R [dL(s)]x(t + s) + f(t)where x and / are ra-dimensional vectors; A is an n x n constant matrix and L(s) is an n x n matrix function with bounded total variation. Some necessary and sufficient conditions are given which guarantee the existence and uniqueness of periodic solutions to the above equation.

关键词： Linear neutral FDE bounded total variation periodic solution

Immune Algorithm for Solving the Optimization Problems of Computer Communication Networks

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The Journal of China Universities of Posts and Telecommunications 2000年第4期7卷 18-24页

作者： GAO Jie 1, WU Xin yu 2.(1. department of applied Mathematics and {2., Nanjing university of Posts and Telecommunications, Nanjing 2.0003, P. R. China 2. department of Electronical Engineering, Nanjing university of Posts and Telecommunications, department of applied Mathematics and {2. Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China department of Electronical Engineering Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China

The basic problem in optimizing communication networks is to assign a proper circuit for each origin destination pair in networks so as to minimize the average network delay, and the network optimal route selection model is a multi constrained 0 1 nonlinear programming problem. In this paper, a new stochastic optimization algorithm, Immune Algorithm, is applied to solve the optimization problem in communication networks. And the backbone network vBNS is chosen to illustrate the technique of evaluating delay in a virtual network. At last, IA is compared with the optimization method in communication networks based on Genetic Algorithm, and the result shows that IA is better than GA in global optimum finding.

关键词： immune algorithm computer communication networks network delay optimal route select

PRIMARY STUDY FOR THE TECHNOLOGY OF ELECTROLESS PLATING Fe-Al-P ALLOYS

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 733-735页

作者： L.L.Wang,L.H.Zhao,W.Y.Hu, X.L.Shu, X.J.Yuan, B.W.Zhang and X.Sheng department of applied {2., hunan university, changsha 410082. China hunan Univ Changsha China

Manuscript received 2. June 1999 The Fe Al P alloy deposits were plated on copper sheets by electroless plating. The change law of the deposition rate, composition, surface appearance and structure for the deposits was studied by changing the metallic salt ratios (AlCl 3/AlCl 3+FeSO 4), the concentration of metallic salt AlCl 3 and reductant NaH 2.O 2. The optimum plating bath was obtained. It was found that the choices of ligand and reductant were the key of increasing Al content for the deposits.

关键词： electroless Fe Al P plating Fe Al P alloys technology structure