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The dynamical properties of Rydberg hydrogen atom near a metal surface

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Science china(physics,Mechanics & Astronomy) 2005年第6期48卷 667-675页

作者： GE Meihua1, ZHANG Yanhui1, WANG Dehua2, DU Mengli3.& LIN Shenglu1 1. College of physics and Electronics, Shandong normal university, Jinan 250014,{3. 2. department of Mathematics and physics, Shandong Institute of Architecture and Engineering, Jinan 250014,{3. 3. Institute of Theoretical physics, Chinese Academy of Sciences, Beijing 100080,{3. 1. College of physics and Electronics Shandong Normal University 250014 Jinan China 2. department of Mathematics and physics Shandong Institute of Architecture and Engineering 250014 Jinan China 3. Institute of Theoretical physics Chinese Academy of Sciences 100080 Beijing China

The dynamical properties of Rydberg hydrogen atom near a metal surface are presented by using the methods of phase space analysis and closed orbit theory. Transforming the coordinates of the Hamiltonian, we find that the phase space of the system is divided into vibrational and rotational region. Both the Poincaré surface of section and the closed orbit theory verify the same conclusion clearly. In this paper we choose the atomic principal quantum number as n = 20. The dynamical character of the exited hydrogen atom depends sensitively on the atom-surface distance d. When d is sufficiently large, the atom-surface potential can be expressed by the traditional van der Waals force and the system is integrable. When d becomes smaller, there exists a critical value dc. For d > dc, the system is near-integrable and the motion is regular. While chaotic motion appears for d < dc, and the system tends to be non-integrable. The trajectories become unstable and the electron might be captured onto the metal surface.

关键词： Rydberg hydrogen atom, van der Waals interaction, Poincaré surface of section, closed orbit theory, chaos.

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Neural Regeneration Research 2006年第8期1卷 763-765页

作者： Xiaofang Chen1, Yueji Sun2, Haiyan Liu1, Yunqiao Ding1, Shujuan Liu1, Jinghua Chen1, Xueying Wang1, Zhenpeng Han3. Fang Qu3.1department of Neurology, dalian Port Hospital, dalian 116015, {3. Province, china 2department of Psychology, dalian Medical university, dalian 116023. {3. Province, china 3.department of Rheumatology, Second Affiliated Hospital of dalian Medical university, dalian 116023. {3. Province, china 4department of Neurology, dalian Second People’s Hospital, dalian 116011, {3. Province, china department of Neurology Dalian Port Hospital Dalian 116015 Liaoning Province China department of Psychology Dalian Medical University Dalian 116023 Liaoning Province China department of Rheumatology Hospital of Dalian Medical University Dalian 116023 Liaoning Province China

BACKGROUND: Cognitive impairment after stroke associates with various factors, such as age, educational years, etc. Besides concerning about the recovery of limb function after stroke, we should also focus on the rehabilitation of cognition. Moreover, we’d better pay attention to the control of all the risk factors of stroke, and improve the quality of life in stroke patients. OBJECTIVE: To analyze the factors that affect cognitive impairment after stroke. DESIGN: A related factors analysis. SETTINGS: department of Neurology of dalian Port Hospital and dalian Second People’s Hospital. PARTICIPANTS: Totally 148 stroke inpatients were selected from department of Neurology, dalian Port Hospital and dalian Second People’s Hospital from April 2004 to December 2005, including 100 males and 48 females, aging 45-75 years with an average age of (67±8) years; Their educational years ranged 2-10 years with an average of (6.1±3.7) years; The disease course ranged 15-3. days; All were right-handed. Inclusive criteria: All were accorded with the diagnostic standard set by the Fourth National Academic Meeting for Cerebrovascular Disease; Confirmed by CT or MRI; Informed consents were obtained from all the subjects. METHODS: After the disease conditions were stable, the patients were assessed with Wechsler memory scale (WMS) and Wisconsin card sorting test (WCST). WMS included forward and backward recitation of numbers and short-term memory (verbal memory, visual recognition). The number of times for correct and wrong classifications in WCST and the time to complete the trail making tests A and B were recorded. The focal volume, area and layer were recorded at 24 hours after admission. The general data of the patients were recorded, including name, sex, age, educational years, history of hypertension, history of diabetes mellitus. Electroencepalograph (EEG) was examined to record the wave shape, blood lipids were detected, and the cognition related indexes were analyzed with the Pe

关键词： Related factors of cognitive impairment after stroke WCST WMS

Challenges in the theoretical investigations of lipid membrane configurations

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Chinese physics B 2013年第2期22卷 36-44页

作者：涂展春 department of physics Beijing Normal University Kavli Institute for Theoretical physics china Chinese Academy of Sciences

We report some key results in the theoretical investigations of configurations of lipid membranes and present several challenges in this field,which involve（i）the exact solutions to the shape equation of lipid vesicles,（ii）the exact solutions to the governing equations of open lipid membranes,（iii）the neck condition of two-phase vesicles in the budding state,（iv） the nonlocal theory of membrane elasticity,and（v）the relationship between the symmetry and the magnitude of the free energy.

关键词： configuration lipid membrane

Rational Form Solitary Wave Solutions and Doubly Periodic Wave Solutions to (1+1)-Dimensional Dispersive Long Wave Equation

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Communications in Theoretical physics 2005年第6期43卷 975-982页

作者： WANG Qi CHEN Yong ZHANG Hong-Qing department of Applied Mathematics, dalian university of Technology, dalian 116024. china department of Mathematics, Ningbo university, Ningbo 3.5211, china department of physics, Shanghai Jiao Tong university, Shanghai 20003., china department of Applied Mathematics Dalian University of Technology department of Mathematics Ningbo University department of physics Shanghai Jiao Tong University

In this work we devise an algebraic method to uniformly construct rational form solitary wave solutionsand Jacobi and Weierstrass doubly periodic wave solutions of physical interest for nonlinear evolution equations. Withthe aid of symbolic computation, we apply the proposed method to solving the (1+1)-dimensional dispersive long wavethe (1+1)-dmensional dispesive long wavedelliptic donbly periodc wave solutions as special cases.

关键词： elliptic equation rational expansion method rational form solitary wave solutions rational form Jacobi and Weierstrass doubly periodic wave solutions symbolic computation (1+1)-dimensional dispersive long wave equation

Variational calculation of the Intrashell 2p^2 ~3.^e State for Heliumlike F^( 7+) ion

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原子与分子物理学报 2000年第4期17卷 743-747页

作者： GUANG Xiao xu 1, WANG Zhi wen(Z.W.Wang) 2(1.Wuhan Institute of physics and Mathematics, Chinese Academy of Science, Wuhan 43.071 2.department of physics,{3. normal university, dalian 116029) 中科院武汉物理与数学所湖北武汉 430071 辽宁师范大学辽宁大连 116029

Doubly excited intrashell 2p 2 3. e state in heliumlike F 7+ ion is calculated by using the modified configuration interaction wave function. Using the modified Slater type wave function having up to 3.2 terms, the energy position of the discrete 2p 2 3. e state in F 7+ is determined to be -18.812 629 78 a.u., Several expectation values of r i,r -1 12 and r 12 are also given in the present work. The present results indicate that the modified Slater type wave function in which r coordinates are incorporated is effective and powerful for the description of the 2p 2 3. e state showing strong correlation effect in two electron systems.

关键词：变分计算壳层氟离子氦状态

The feature study on the π and proton rapidity distributions at AGS, SPS and RHIC

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Science china(physics,Mechanics & Astronomy) 2009年第2期52卷 198-206页

作者： FENG ShengQin1,2 & YUAN XianBao1,3.1 College of Science, china Three Gorges university, Yichang 443.02, china 2 School of {3. and Technology, Wuhan university, Wuhan 43.072, china 3.Institute of Particle {3., Central china normal university, Wuhan 43.070, china 1. College of Science China Three Gorges University Yichang 443002 China 2. School of physics and Technology Wuhan University Wuhan 430072 China 3. Institute of Particle physics Central China Normal University Wuhan 430070 China

The features of nuclear stopping power and multi-hadron production systematically are studied by making an analysis of rapidity distributions of pion and proton at AGS, SPS and RHIC in this work. It is found that nuclear stopping power increases linearly with project rapidity yp at AGS and SPS, but that is not liner at RHIC. It is argued that the average rapidity loss is saturated at central rapidity region at RHIC. For pion distribution, it is found that the phase space of pion distribution distributes uniformly in the longitudinal direction,and a linear relationship of L with log s is given at AGS and SPS. Non-uniform flow model may explain the features of the distribution at AGS and SPS, but may not ex- plain those of at RHIC.

关键词： non-uniform flow model average rapidity loss baryon number density nuclear stopping power

LEVEL SET METHOD FOR TOPOLOGICAL OPTIMIZATION APPLYING TO STRUCTURE, MECHANISM AND MATERIAL DESIGNS

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Chinese Journal of Mechanical Engineering 2004年第2期17卷 200-209页

作者： Mei Yulin Wang Xiaoming department of Mechanical Engineering,dalian university of Technology,dalian 116024,china department of Mechanical Engineering Dalian University of Technology Dalian 116024 China

Based on a level set model, a topology optimization method has been suggestedrecently. It uses a level set to express the moving structural boundary, which can flexibly handlecomplex topological changes. By combining vector level set models with gradient projectiontechnology, the level set method for topological optimization is extended to a topologicaloptimization problem with multi-constraints, multi-materials and multi-load cases. Meanwhile, anappropriate nonlinear speed, mapping is established in the tangential space of the activeconstraints for a fast convergence. Then the method is applied to structure designs, mechanism andmaterial designs by a number of benchmark examples. Finally, in order to further improvecomputational efficiency and overcome the difficulty that the level set method cannot generate newmaterial interfaces during the optimization process, the topological derivative analysis isincorporated into the level set method for topological optimization, and a topological derivativeand level set algorithm for topological optimization is proposed.

关键词： Level set method Topology optimization Mean curvature flow Materialdesign Mechanism design Topological derivative

A Series of Soliton-like and Double-like Periodic Solutions of a (2+1)-Dimensional Asymmetric Nizhnik-Novikov-Vesselov Equation

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Communications in Theoretical physics 2004年第11期42卷 655-660页

作者： CHEN Yong,~(1,3.4, WANG Qi~(2,4) LI Biao~(2,4) ~1department of Mathematics,Ningbo university,Ningbo 3.5211,china ~2department of Applied Mathematics,dalian university of Technology,dalian 116024,china ~3.0} of physics,Shanghai Jiao Tong university,Shanghai 20003.,china ~4Key Laboratory of Mathematics Mechanization~ the Chinese Academy of Sciences,Beijing 100080,china Key Laboratory of Mathematics Mechanization the Chinese Academy of Sciences Beijing 100080 China

We generalize the algebraic method presented by Fan [***.A:***.3. (2003. 7009)] to uniformlyconstruct a series of soliton-like solutions and double-llke periodic solutions for nonlinear partial differential equations(NPDE),As an application of the method,we choose a (2+1)-dimensional asymmetric Nizhnik-Novikov-Vesselov equa-tion and successfully construct new and more general solutions including a series of nontraveling wave and coefficientfunctions’ soliton-like solutions,double-like periodic and trigonometric-like function solutions.

关键词： symbolic computation soliton-like solution Weierstrass and Jacobi elliptic functions periodic solution

B→K~*γ Decay in Top-Quark Two-Higgs-Doublet Model

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Communications in Theoretical physics 2006年第11期46卷 895-900页

作者： XIAO Zhen-Jun,~+ CHENG Hui-Hui, and L Lin-Xia department of physics and Institute of Theoretical physics, Nanjing {3. university, Nanjing 210097, china department of physics Nanjing Normal University Institute of Theoretical physics Nanjing Normal University

By employing the QCD factorization approach for the exclusive B→Vγ decays, we study the exclusive decay B→K~*γ in the top-quark two-Higgs-doublet model (T2HDM). Within the considered parameter space, we find the following conclusions (a) A light charged-Higgs boson with a mass about 200 GeV is clearly excluded by the date of B→K~*γ decay, and this lower limit is comparable with that from the inclusive B→Xγ decay; (b) The theoretical predictions for CP asymmetry of B→K~*γ in the T2HDM is always less than 1% in size; and (c) The isospin symmetry breaking for B→K~*γ decay in the SM and T2HDM considered here is around 6% in size and well consistent with the data and the general expectations.

关键词： B meson decay charged-Higgs boson branching ratio CP asymmetry