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Quantum statistical entropy corresponding to cosmic horizon in five-dimensional spacetime

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Science china(physics,Mechanics & Astronomy) 2008年第2期51卷 140-146页

作者： ZHAO Ren1,2.& ZHANG ShengLi1 1 Department of applied physics, Xi’an Jiaotong University, Xi’an 710049,{2. 2.Department of physics, Shanxi Datong University, Datong 037009,{2. Department of applied physics Xi’an Jiaotong University Xi’an 710049 China Department of physics Shanxi Datong University Datong 037009 China

The generalized uncertainty relation is introduced to calculate the quantum statis-tical entropy corresponding to cosmic horizon. By using the new equation of state density motivated by the generalized uncertainty relation, we discuss entropies of Bose field and Fermi field on the background of five-dimensional spacetime. In our calculation, we need not introduce cutoff. There is no divergent logarithmic term in the original brick-wall method. And it is obtained that the quantum statistical en-tropy corresponding to cosmic horizon is proportional to the area of the horizon. Further it is shown that the entropy corresponding to cosmic horizon is the entropy of quantum state on the surface of horizon. The black hole's entropy is the intrinsic property of the black hole. The entropy is a quantum effect. In our calculation, by using the quantum statistical method, we obtain the partition function of Bose field and Fermi field on the background of five-dimensional spacetime. We provide a way to study the quantum statistical entropy corresponding to cosmic horizon in the higher-dimensional spacetime.

关键词： quantum statistical entropy generalized uncertainty relation high-dimensional spacetime

Transient species and its properties of melatonin

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Science china Chemistry 2006年第4期49卷 308-314页

作者： ZHU Hongping1,2. ZHANG Zhaoxia1,2. ZHAO Hongwei1, WANG Wenfeng1 & YAO Side1 1. Shanghai institute of applied {2., Chinese Academy of Sciences, Shanghai 2.1800, china 2. Graduate University of the Chinese Academy of Sciences, Beijing 100049, china 1. Shanghai institute of applied {2. Chinese Academy of Sciences Shanghai 201800 China 2. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The photo-physical and photo-chemical properties of melatonin (ML) werestudied by 2.6 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radicalcation of ML (ML^(·+))and hydrated electrons (e_(aq)^-), while excited triplet state ~3ML~* is alsoformed during photolysis. The oxidation via one electron transfer from ML to SO_4^(·+) and thetriplet state of riboflavin (~3RF~*) has been also investigated and the rate constants for theprocess have been determined to be 8.0x10^9 and 1.4x10^9 L·mol^(-1)·s^(-1) respectively. Theradical cation of 2.2.'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS^(·+)) scavengingcapacities of melatonin and other antioxidants are compared in this paper.

关键词： melatonin, laser flash photolysis, photoionization, triplet state.

DIFFERENCE SCHEMES WITH NONUNIFORM MESHES FOR NONLINEAR PARABOLIC SYSTEM

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Journal of computational Mathematics 1996年第4期14卷 319-335页

作者： Y.L. Zhou(Laboratory of computational physics, Centre for Nonlinear Studies, {2. of appliedphysics and computational Mathematics, Beijing, china) INST APPL PHYS & COMPUTAT MATH CTR NONLINEAR STUDIESLAB COMPUTAT PHYSBEIJING 100088PEOPLES R CHINA

The boundary value problem for the nonlinear parabolic system is solved by the finite difference method with nonuniform meshes. The existence and a priori estemates of the discrete vector solutions for the general difference schemes with unequal meshsteps are established by the fixed point technique. The absolute and relative convergence of the discrete vector solution are justified by a series of a priori estimates. The analysis of mentioned problems are based on the assumption of heuristic character concerning the existence of the unique smooth solution for the original problem of the nonlinear parabolic system.

关键词： Math QT DIFFERENCE SCHEMES WITH NONUNIFORM MESHES FOR NONLINEAR PARABOLIC SYSTEM

Regularity criterion to some liquid crystal models and the Landau-Lifshitz equations in R^3

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Science china Mathematics 2008年第10期51卷 1787-1797页

作者： FAN JiShan1 & GUO BoLing2.1 College of Information Science and Technology, Nanjing Forestry University, Nanjing 2.0037, china 2.institute of {2. physics and computational Mathematics, P. O. Box 8009, Beijing 100088, china College of Information Science and Technology Nanjing Forestry University Nanjing 210037 China institute of applied {2. and computational Mathematics P. O. Box 8009 Beijing 100088 China

We consider the regularity problem under the critical condition to some liquid crystal models and the Landau-Lifshitz equations. The Serrin type reularity criteria are obtained in the terms of the Besov spaces.

关键词： liquid crystal Landau-Lifshitz equations critical condition Besov space

The study of two-color excitation upconversion of Pr(0.5)Yb(3):ZBLAN

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 169-177页

作者： CHEN Xiaobo1 & SONG Zengfu2.1. applied Optics Beijing Area Major Laboratory, Analysis and testing center, Beijing Normal University, Beijing 100875, china 2. Peking University, {2. School, Beijing 100871, china applied Optics Beijing Area Major Laboratory Analysis testing center Beijing Normal University Beijing 100875 China physics School Peking University Beijing 100871 China

The excited state absorption upconversion of Pr(0.5)Yb(3):ZBLAN glass material, under two-color excitation of the 960 nm semiconductor laser and the Xe lamp light simultaneously, is reported in this article. It was found that the upconversion emission spectra of 480.1, 519.0, 601.9 and 631.8 nm coincide with the common emission spectra. Meanwhile, the upconversion-excitation spectrum has three obvious peaks under two-color excitation, and they respectively correspond to the 856.0 nm upconversion ex-citation transition [1G4(Pr3+)→1I6(Pr3+) and 1G4(Pr3+)→3P1(Pr3+)], the 789.0 nm upconver-sion excitation transition 1G4(Pr3+)→3P2.Pr3+), and the 803.7 nm upconversion excitation transition 3H6(Pr3+)→1D2.Pr3+). The upconversion excitation transition 1G4(Pr3+)→1I6(Pr3+) is strong because its oscillator strength f = 2..040×10?6 is large, which results in a large peak appearing in the upconversion excitation spectrum. That is just the new interesting two-color excitation upconversion luminescence phenomenon of Pr(0.5)Yb(3):ZBLAN induced by one laser and one continuous normal light simultaneously.

关键词： upconversion volumetric three-dimensional display two-color excitation.

Steady-state responses of axially accelerating viscoelastic beams: Approximate analysis and numerical confirmation

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Science china(physics,Mechanics & Astronomy) 2008年第11期51卷 1707-1721页

作者： CHEN LiQun1,2.& DING Hu2.1 Department of Mechanics, Shanghai University, Shanghai 2.0444, china 2.Shanghai institute of {2. Mathematics and Mechanics, Shanghai 2.0070, china Department of Mechanics Shanghai University Shanghai 200444 China Shanghai institute of applied Mathematics and Mechanics Shanghai 200070 China

Nonlinear parametric vibration of axially accelerating viscoelastic beams is inves-tigated via an approximate analytical method with numerical confirmations. Based on nonlinear models of a finite-small-stretching slender beam moving at a speed with a periodic fluctuation, a solvability condition is established via the method of multiple scales for subharmonic resonance. Therefore, the amplitudes of steady-state periodic responses and their existence conditions are derived. The amplitudes of stable steady-state responses increase with the amplitude of the axial speed fluctuation, and decrease with the viscosity coefficient and the nonlinear coefficient. The minimum of the detuning parameter which causes the existence of a stable steady-state periodic response decreases with the amplitude of the axial speed fluctuation, and increases with the viscosity coefficient. Nu-merical solutions are sought via the finite difference scheme for a nonlinear par-tial-differential equation and a nonlinear integro-partial-differential equation. The calculation results qualitatively confirm the effects of the related parameters pre-dicted by the approximate analysis on the amplitude and the existence condition of the stable steady-state periodic responses. Quantitative comparisons demonstrate that the approximate analysis results have rather high precision.

关键词： nonlinearity parametric vibration axially accelerating beam method of multiple scales numerical confir-mation

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 physics and IT, Medical College, Shantou University,Shantou 515041, china 2. Department of physics, 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

A high power MOPA free-electron laser with narrowline-width

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Nuclear Science and Techniques 1999年第3期10卷 165-167页

作者： SHU Xiaojian (institute of Modern physics, Fudan University, Shanghai 2.0433 institute of applied physics and computational Mathematics, Beijing 100088) 复旦大学物理系上海

A new kind of MOPA configuration to obtain a high power free-electron laser with very narrow line-width that can satisfy the requirements of some applications such as the laser isotope separation has been proposed, wh... 详细信息

关键词：自由电子激光器线宽窄功率大

On the Asymptotic Behavior of Nonlinear Schrodinger Equations with Magnetic Effect

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Acta Mathematica Sinica,English Series 1995年第2期11卷 179-187页

作者： Guo Boling Tan Shaobin institute of applied {2. and computational Mathematics Academia Sinica Beijing, 100088 china institute of applied {2. and computational Mathematics Academia Sinica Beijing People's Republic of China

The purpose of this paper is to study the long time asymptotic behavior for a nonlinear Schrdinger equations with magnetic effect. Under certain conditions, we prove the existence and nonexistence of the non-trivial f... 详细信息

关键词： Math On the Asymptotic Behavior of Nonlinear Schrodinger Equations with Magnetic Effect