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B→Xsγ, Xsl+l~-Decays and Constraints on Mass Insertion Parameters in MSSM

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Communications in theoretical physics 2006年第10期46卷 687-696页

作者： XIAO Zhen-Jun,~+ LI Feng-Ying, and ZOU Wen-Jun Department of physics and institute of {2. physics, Nanjing normal university, Nanjing 2.0097, china Department of physics and institute of {2. physics Nanjing Normal University Nanjing 210097 China

In this paper, we study the upper bounds on the mass insertion parameters (δ~q)in the minimal supersymmetric standard model. We found that the information from the measured branching ratio of B→Xl+l~-decaycan help us to improve the upper bounds on the mass insertions parameters(δ. Some regions allowed by thedata of Br(B→Xγ)are excluded by the requirement of an SM-like C(m)imposed by the data of Br(B→Xl+l~-).

关键词： B meson decay the minimal supersymmetric standard model mass insertion

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 {2. 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

Existence of the solutions and the attractors for the large-scale atmospheric equations

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Science china Earth Sciences 2006年第6期49卷 650-660页

作者： HUANG Haiyang1 & GUO Boling2.1. Department of Mathematics, Beijing normal university, Beijing 100875, {2. 2. institute of Applied physics and Computational Mathematics, Beijing 100080, {2. Department of Mathematics Beijing Normal University Beijing China institute of Applied physics and Computational Mathematics Beijing China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.

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 {2., Jinan 2.0100, china 2. School of physics and Microelectronics, Shandong {2., Jinan 2.0061, china institute of theoretical Chemistry Shandong University Jinan China School of physics and Microelectronics Shandong University Jinan 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.

Morphology and the M_(BH)-σ_* relation for NLS1s

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Science china(physics,Mechanics & Astronomy) 2010年第S1期53卷 256-258页

作者： BIAN WeiHao & HUANG Li Department of physics and institute of {2. physics,Nanjing normal university,Nanjing 2.0097,china Department of physics and institute of {2. physics Nanjing Normal University Nanjing China

For a sample of 33 narrow-line Seyfert 1 galaxies(NLS1s)(z<0.1) from the Sloan Digital Sky Survey,we investigate their *** find that 2. NLS1s show clear bar structure and 9 NLS1s show no bar *** bar frequency in this ... 详细信息

For a sample of 33 narrow-line Seyfert 1 galaxies(NLS1s)(z2. NLS1s show clear bar structure and 9 NLS1s show no bar *** bar frequency in this NLS1s sample is about 70%.We do not find any difference in the location of NLS1s with or without bars on the MBH-σ* diagram.

关键词： active galaxies bar black hole mass

D-Dimensional Dirac Fermions BEC-BCS Crossover Thermodynamics

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Communications in theoretical physics 2007年第7期48卷 99-106页

作者： CHEN Ji-Sheng institute of Particle physics & physics Department,Central china normal university,Wuhan 430079,china institute of Particle physics & physics Department Central China Normal University Wuhan 430079 China

An effective relativistic continuum massive Proca Lagrangian action is used to account for the Lorentzvector condensation effects on the equation of state of the strongly interacting fermions *** interior quantumfluctuation effects are incorporated as an external field approximation indirectly through a fictive generalized ThomsonProblem counterterm *** general analytical formulas for the d-dimensional thermodynamics are given nearthe unitary limit region,In the non-relativistic limit for d=3,the universal dimensionless coefficientε=4/9 andenergy gap △/ε_f=5/18 are reasonably consistent with the existing theoretical and experimental *** the unitarylimit for d=2.and T=0,the universal coefficient can even approach the extreme occasion ξ=0 corresponding to theinfinite effective fermion mass m~*=∞,which can be mapped to the strongly coupled two-dimensional electrons and isquite similar to the three-dimensional Bose-Einstein condensation of ideal boson ***,for d=1,the universalcoefficient ξ is negative,implying the non-existence of phase transition from superfluidity to normal *** solutionsmanifest the quantum Ising universal class characteristic of the strongly coupled unitary fermions gas.

关键词： unitary fermions thermodynamics BEC-BCS crossover statistical methods

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 {2., Jinan 2.0014, china 2. Department of Mathematics and physics, Shandong institute of Architecture and Engineering, Jinan 2.0014, china 3. institute of theoretical physics, Chinese Academy of Sciences, Beijing 100080, china College of physics and Electronics Shandong Normal University Jinan China Department of Mathematics and physics Shandong Institute of Architecture and Engineering Jinan China institute of theoretical {2. Chinese Academy of Sciences 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 = 2.. 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.

Maximal possible accretion rates for slim disks

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Science china(physics,Mechanics & Astronomy) 2009年第12期52卷 2054-2058页

作者： LIN YiQing1 & JIAO ChengLiang2.1 Department of Mathematics and physics,Xiamen university of Technology,Xiamen 36102.,{2. 2.Department of physics and institute of theoretical physics and Astrophysics,Xiamen university,Xiamen 361005,{2. Department of Mathematics and physics Xiamen University of Technology Xiamen China Department of physics and institute of {2. physics and Astrophysics Xiamen University Xiamen China

It was proved in the previous work that there must be a maximal possible accretion rate $ \dot M_{max} $ for a slim disk. Here we discuss how the value of $ \dot M_{max} $ depends on the two fundamental parameters of the disk, namely the mass of the central black hole M and the viscosity parameter α. It is shown that $ \dot M_{max} $ increases with decreasing α, but is almost independent of M if $ \dot M_{max} $ is measured by the Eddington accretion rate $ \dot M_{Edd} $ , which is in turn proportional to M.

关键词： accretion disks black hole physics hydrodynamics

The geodetic numbers of graphs and digraphs

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Science china Mathematics 2007年第8期50卷 1163-1172页

作者： Chang-hong LU~(1,2. 1 Department of Mathematics,East china normal {2.,Shanghai 2.0062.china 2.institute of theoretical Computing,East china Narnal {2.,Shanghai 2.0062.china Department of Mathematics East China Normal University Shanghai China institute of theoretical Computing East China Narnal University Shanghai China

For every two vertices u and v in a graph G, a u-v geodesic is a shortest path between u and v. Let I(u, v) denote the set of all vertices lying on a u-v geodesic. For a vertex subset S, let I(S) denote the union of all I(u, v) for u, v ∈ S. The geodetic number g(G) of a graph G is the minimum cardinality of a set S with I(S) = V (G). For a digraph D, there is analogous terminology for the geodetic number g(D). The geodetic spectrum of a graph G, denoted by S(G), is the set of geodetic numbers of all orientations of graph G. The lower geodetic number is g ?(G) = minS(G) and the upper geodetic number is g +(G) = maxS(G). The main purpose of this paper is to study the relations among g(G), g ?(G) and g +(G) for connected graphs G. In addition, a sufficient and necessary condition for the equality of g(G) and g(G × K 2. is presented, which improves a result of Chartrand, Harary and Zhang.

关键词： convex set digraph distance geodesic geodetic number 05C12 05C2.