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New Exact Solutions to (2.1)-Dimensional Variable Coefficients Broer-Kaup Equations

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Communications in Theoretical physics 2006年第9期46卷 393-396页

作者： ZHU Jia-Min~(1,2.+) MA Zheng-Yi~(1,2. ~1 department of physics, Zhejiang {2. University, lishui 3.3.00, china ~2.Shanghai Institute of Applied Mathematics and Mechanics, Shanghai 2.0072. china department of physics Zhejiang Lishui University Shanghai Institute of Applied Mathematics and Mechanics

In this paper, using the variable coefficient generalized projected Ricatti equation expansion method, we present explicit solutions of the (2.1)-dimensional variable coefficients Broer-Kaup (VCBK) equations. These solutions include Weierstrass function solution, solitary wave solutions, soliton-like solutions and trigonometric function solutions. Among these solutions, some are found for the first time. Because of the three or four arbitrary functions, rich localized excitations can be found.

关键词： variable coefficient generalized projected Ricatti equation method (2.1)-dimensional variable coefficients Broer Kaup equations Weierstrass function solution solitary wave solution trigonometric function solution

Charge order and spin order in Nd_(0.5)Sr_(0.5)Mn_(1-x)(Ga_x, Ti_x)O_3 system

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Science china(physics,Mechanics & Astronomy) 2007年第3期50卷 294-302页

作者： REN QingBao1,2. ZHU WeiTing1, hong Bo2.& ZHANG YuHeng2.1 {2. of physics, lishui University, lishui 3.3.00, china 2.National High Magnetic Field laboratory, University of Science and Technology of china, Hefei 2.002., china 1. department of physics Lishui University Lishui 323000 China 2. National High Magnetic Field laboratory University of Science and Technology of China Hefei 230026 China

Magnetic properties of Nd_(0.5)Sr_(0.5)Mn_(1-x)(Ga_x, Ti_x)O_3 system (0.04≤x≤0.4) were inves- tigated through magnetization and electron spin resonance (ESR) measurements. It was observed that a small amount of Ti substitution for Mn will destroy the charge-ordering (CO) phase completely and induce the cluster-spin-glass phase in the system, which displays a procedure of collapse of CO and of an enhancement of spin ordering (SO) phase. In contrast, the Ga substitution for Mn induces a melt- ing of CO phase in the system. It was observed that with substitution the CO phase is suppressed gradually and the remanent CO phase is retained all the while, and withal, there is a co-existence of AFM CO phase and FM SO at low temperature. In addition, an abrupt rise of magnetization was observed in M-T curves. We attributed this abnormal phenomenon to a transition from canted AFM SO to FM SO in CO region.

关键词： charge ordering spin ordering antiferromagnetic transition

Adsorption of platinum(Ⅳ)onto D3.1R resin

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Rare Metals 2008年第3期27卷 233-237页

作者： MO Jianjun SHI linmei GU Yongbing YAN Guobing department of Chemistry Lishui College Lishui 323000 China lishui Technical College Lishui 323000 China

Pt（Ⅳ） was quantitatively adsorbed by D3.1R resin in the medium of pH = 3.47. The statically saturated adsorption capacity is 410 mg/g. Pt（Ⅳ） adsorbed on D3.1R resin can be eluted by 1.0-2.0 mol/l NaOH. The rate constant is k2.8 = 5.43 × 10^-5 s^-1. The adsorption of Pt（Ⅳ） on D3.1R resin obeys the Freundlich isotherm. The adsorption parameters of thermodynamics are as follows： enthalpy change AH = 4.37 kJ/mol, Gibbs free energy change AG = -5.39 kJ/mol, and entropy change AS = 32.76 J/（mol.K）. The apparent activation energy is Ea = 2..5 kJ/mol. The coordination molar ratio of the functional group of D3.1R resin to Pt（Ⅳ） is 2.1.

关键词： D3.1R resin adsorption platinum adsorption mechanism

Anisotropic effect on the vibronic reduction factors

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Chinese Science Bulletin 2006年第21期51卷 2553-2558页

作者： QIU Qing-chun1,2.& QIAO Fen1,2.1. department of {2. and IT, Medical College, Shantou University,Shantou 515041, china 2. department of {2., Shantou University, Shantou 515063, china department of physics and IT Medical College Shantou University Shantou 515041 China department of physics Shantou University Shantou 515063 China

The reduction factors p and q defined by Ham in the Ee JT system and their relation 2.-p=1 have been well accepted and the concept of reduction factors is widely used in the studies of vibronic coupling. However, when the system is under the anisotropic conditions, the reduction factors and their relation will change accordingly. The first-order reduction factors p and q of Ee system were further studied using the method of unitary transformation here. The relation between p and q proposed by Ham was investigated under both conditions of the linear coupling and the anisotropic effects. The result demonstrated that the relation of 2.-p=1 was only correct for the linear vibronic coupling, but not correct when the anisotropic effect was considered. This result suggested that the anisotropic effect influence considerably the reduction factors, and hence the physical properties of materials. Our method could be also applied to other JT systems, especially the highly symmetric JT systems involving C60 molecules.

关键词：电子振动耦合声子交迭 Jahn-Teller效应各向异性

Effect of an impurity on 3-electron quantum dots in magnetic fields

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Science china(physics,Mechanics & Astronomy) 2004年第5期47卷 521-530页

作者： lIU Yimin1,2. HUANG Gangming1 & BAO Chengguang1 1. department of physics, Z{2.shan University, Guangzhou 5102.5, china 2. department of physics, Shaoguan University, Shaoguan 512.05, china 1. department of physics Zhongshan University 510275 Guangzhou China 2. department of physics Shaoguan University 512005 Shaoguan China

The ground-state property of a 2.dimensional 3-electron quantum dot (QD) subjected to an external magnetic fieldB and affected by an impurity is studied. The impurity is located at thez-axis by a distanced from the plane of the dot. The evolution of the angular momentuml o and the spinS o of the ground state in accordance withB andd has been calculated, and the results are summarized and plotted in a (l o,S o) diagram. The spatial distribution of the electrons (the size and the geometric features) and the optical absorption have also been investigated. The (l o S o) diagram indicates thatl o andS o may jump whend and/orB vary. It was found that, due to the constraints arising from symmetry, each symmetric geometry is accessible only to a specific group of states having specificl o andS o.

关键词： quantum dot, ground state, charged impurity, magnetic field.

Density-functional formula for strongly correlated systems

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Progress in Natural Science:Materials International 2005年第5期15卷 395-401页

作者： WANG Huaiyu1*, HAN Rushan2.and CHEN Nanxian1(1. department of physics, Tsinghua University, Beijing 100084, {2. 2. department of physics, Peking University, Beijing 100871, {2.) department of physics Tsinghua University Beijing 100084 China department of physics Peking University Beijing 100871 China

Density functional method is applied for strongly correlated systems. Based on the assumption that the systems are composed of electrons in singly-occupied orbitals and those in doubly-occupied orbitals, a set of self-consistent equations are obtained by standard variation procedure. The equations consist of two parts. One part is to solve the wave functions of the electrons in singly-occupied orbitals and the other is to solve the wave functions of the electrons in doubly-occupied orbitals. The physical meanings of the terms appearing in the equations are discussed.

关键词： density-functional theory strongly correlated systems doubly-occupied orbital two-particle wave function self-consistent equations.

Improved Reall-Santos method for AdS black holes in general 4-derivative gravities

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Science china(physics,Mechanics & Astronomy) 2024年第8期67卷 74-86页

作者： Peng-Ju Hu liang Ma hong lü Yi Pang Center for Joint Quantum Studies and department of physics School of ScienceTianjin UniversityTianjin 300350China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207China Peng Huanwu Center for Fundamental Theory Hefei 230026China

For asymptotically flat black holes,Reall-Santos method is a convenient tool to compute leading higher derivative corrections to the thermodynamic quantities without actually solving the modified field ***,there are subtleties in its generalization to asymptotically AdS black holes with general higher derivative *** of all,it is necessary to know all the higher derivative holographic counterterms and the surface terms implementing the variational principle and subtracting the *** then needs to solve for the modified AdS radius and rescale the time coordinate in an appropriate way such that the induced metric on the conformal boundary of AdS black hole is not *** observe that Reall-Santos method can be directly applied to a particular 4-derivative gravity model,known as the Einstein-Weyl gravity,which does not modify the AdS radius and requires only the Gibbons-Hawking-York term and holographic counterterms for the 2.derivative *** thus suggest that to compute the thermodynamic quantities of AdS black holes in general 4-derivative theories of gravity,one simply needs to transform it to a Einstein-Weyl gravity with identical thermodynamic variables by appropriate field *** explicitly verify this proposal with spherically-symmetric and static charged black holes in Einstein-Maxwell theory extended with generic 4-derivative interactions.

关键词： black holes thermodynamics higher-derivative corrections effective theories higher dimensional black holes quantum gravity

W ^(1,p)(R^n)-BOUNDEDNESS FOR MAXIMAl FUNCTIONS

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Analysis in Theory and Applications 2009年第1期25卷 86-91页

作者： li Cheng department of Mathematics lishui University lishui, 3.3.00P. R. china department of Mathematics Lishui University Lishui 323000 P. R. China

In this paper, we get W 1,p(Rn)-boundedness for tangential maximal func- tion and nontangential maximal function , which improves ***, *** and Tananka’s results.

关键词： tangential maximal function nontangential maximal function W 1 p(Rn)- boundedness

Stochastic resonance in surface catalytic oxidation of carbon monoxide induced by colored noise

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Science china Chemistry 2004年第2期47卷 106-112页

作者： GONG Yubing1,2. HOU Zhonghuai1 & XIN Houwen1 1. department of Chemical {2., University of Science and Technology of china, Hefei 2.002., china 2. department of {2., Yantai Teachers University, Yantai 2.402., china 1. department of Chemical physics University of Science and Technology of China 230026 Hefei China 2. department of physics Yantai Teachers University 264025 Yantai China

The dynamical behavior of surface catalytic oxidation reaction of Pt(110)/CO+O2.modulated by colored noise, under the condition of specific temperature, has been investigated when the partial pressure of CO gas is near the supercritical Hopf bifurcation point. By computer simulation the oscillation and stochastic resonance induced by colored noise are observed. The influences of the intensity and correlation time of colored noise on stochastic resonance are discussed. The range of sensitivity of the system to the environmental fluctuation is analyzed.

关键词： colored noise, stochastic resonance, surface catalytic reaction of Pt(110)/CO+O2. supercritical Hopf bifurcation, signal-to-noise ratio (SNR).