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A Note on Wigner Functions and *-Genvalue Equation

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Communications in Theoretical physics 2009年第4期51卷 605-608页

作者： JING Si-Cong LIN Bing-Sheng department of {1. physics,{3. of Science and technology of china,hefei 230026,china department of {1. physics University of Science and Technology of China Hefei 230026 China

In deformation quantization,static Wigner functions obey functional *-genvalue equation,which is equiv-alent to time-independent Schr■dinger equation in Hilbert space operator formalism of quantum *** equiv-alence is proved mostly for Hamiltonian with form H=（1.2）■;+V（■）[***,***.60（1.64）581..In this note we generalize this proof to a very general Hamiltonian H（■,■）and give examples to support it.

关键词： Wigner function *-genvalue equation deformation quantization

A study of two-dimensional magnetic polaron

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Science china({1.,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1, ZHANG Huaihong1, FENG Mang1,2 & WANG Kelin1,3.1. School of Science, Southwest university of Science and technology, Mianyang 621010, china 2. Wuhan Institute of {3. and Mathematics, Chinese Academy of Sciences, Wuhan 43.070, china 3. department of modern physics, university of Science and technology of china, hefei 230026, china School of Science Southwest University of Science technology Mianyang 621010 China Wuhan Institute of physics Mathematics Chinese Academy of Sciences Wuhan 430070 China department of {1. physics University of Science technology of{1. Hefei 230026 China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

Bell violation for the thermal states of an XXZ spin chain with Dzialoshiski-Moriya interaction

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Science china({1.,Mechanics & Astronomy) 2010年第11期53卷 2074-2079页

作者： MA XiaoSan 1 & WANG AnMin 2 1 School of Electric Engineering and Information,Anhui university of technology,Maanshan 243.02,china 2 {3. of modern physics,university of Science and technology of china,hefei 230026,china 1. School of Electric Engineering and Information Anhui University of Technology Maanshan 243002 China2. Department of Modern Physics University of Science and Technology of China Hefei 230026 China

The effect of Dzialoshiski-Moriya (DM) interaction on the violation of Bell inequality for thermal states of interacting qubits via a two-qubit XXZ spin chain is *** results imply that the DM interaction and anisotropy taking a large positive value can enhance the Bell violation and improve the threshold temperatures of *** the comparison between the Bell violation and thermal entanglement,we find that the threshold temperatures of thermal entanglement are higher than those of the Bell *** implies that some states are entangled but the Bell inequality is not violated.

关键词： Bell violation threshold temperatures DM interaction

Degradation of nitrobenzene in wastewater by γ-ray irradiation

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Journal of Environmental Sciences 2004年第3期16卷 364-366页

作者： ZHANG Shu juan 1, FENG Shao hong 1, YU Han qing 1,* , LI Qian rong 2 (1 department of Chemistry, university of Science & technology of{3., hefei 230026,{3.. 2 Research Center for physics & Chemistry, university of Science & technology of{3., hefei 230026,{3.) department of Chemistry University of Science & Technology of China Hefei 230026 China.

The degradation of nitrobenzene(NB) by γ ray irradiation was studied. The influences of dose rate and initial NB concentration were investigated in details. At a dose rate of 55 Gy/min, the degradation kinetics was pseudo first order at NB concentrations from 0 2 mmol/L to 4 0 mmol/L. At an initial NB concentration of 0 8 mmol/L, the degradation of NB at various dose rates also followed pseudo first order kinetics. Dissolved oxygen was found to have a positive effect on NB degradation. The degradation products were identified as nitrophenol, nitrosobenzene, and hydroquinone, and so on. Based on the product analysis, possible degradation pathways of nitrobenzene were proposed.

关键词： degradation irradiation nitrobenzene(NB) kinetics

Internal noise stochastic resonance in CO oxidation on nm-sized palladium particles

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Science china Chemistry 2005年第5期48卷 395-401页

作者： GONG Yubing1.2, HOU Zhonghuai1.& XIN Houwen1.1. department of Chemical {1., university of Science and {3. of china, hefei 230026, china 2. department of {1., Yantai Teachers university, Yantai 264025, china 1. department of Chemical {1. University of Science and Technology of China 230026 Hefei China 2. department of {1. Yantai Teachers University 264025 Yantai China

Based on a stochastic mesoscopic model, the influence of internal noise on the oscillatory kinetics of the catalytic oxidation of CO on nm-sized palladium particles is studied, using the chemical Langevin equations, Poisson approximation algorithm, and exact stochastic simulation algorithm. The reaction rate oscillations are of stochastic nature due to considerable internal noise in such mesoscopic systems. It is found that the performance of the stochastic oscillations undergoes a maximum with the variation of internal noise level for a given CO partial pressure, which demonstrates the occurrence of internal noise stochastic resonance. This phe-nomenon implies that optimal internal noise would favor the reaction rate oscillation of CO oxi-dation on nm particles. Such a phenomenon is robust to the change of external parameters, such as CO pressures.

关键词： nanometer-sized palladium particles, surface catalytic CO oxidation, internal noise, stochastic resonance, chemical Langevin equation.

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

The dynamical behavior of surface catalytic oxidation reaction of Pt(1.0)/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(1.0)/CO+O2, supercritical Hopf bifurcation, signal-to-noise ratio (SNR).

A STUDY OF OSCILLATING FLOWS OVER PROPAGATING RIPPLES:PART Ⅱ. VORTICITY DYNAMICS

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Journal of Hydrodynamics 2000年第1期12卷 8-15页

作者： Lu Xi yun department of {1. Mechanics, university of Science and {3. of china, hefei 230026, P.R.china Univ of Science and technology of China Hefei China

Vortex shedding for an oscillating flow over ripples is numerically investigated by solving 2 D time dependent incompressible Navier Stokes equations in curvilinear coordinates. The dynamics of vortex structures generated by flow separation is studied in order to understand some phenomena which take place near the bottom and in particular to get insight into the mechanism through which sediment grains are lifted up and maintained in suspension. Based on our calculated results, some important phenomena, such as vortex shedding, vortices pairing, vortices coalescence, vortex interaction with the free shear layer and so on, can be found. The behaviors of energy dissipation in the flow field and of shear stress along the ripple surface are also discussed for studying the dynamics of sediment grains in suspension and to obtain new information on the suspended load over the ripples.

关键词： oscillating flow ripple vorticity dynamics separation flow

Z^+(443.) and Analogous Heavy Flavor States

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原子核物理评论 2009年第S1期26卷 39-43页

作者： DING Gui-jun(department of {1. physics,{3. of Science and technology of china,hefei 230026,china) department of {1. physics University of Science and Technology of ChinaHefei 230026China

We have studied Z+(443.)as a D*D1.molecule from the quark model,state mixing effect is considered by solving the coupled channel Schrdinger equation numerically. More precise measurements of Z+(443.)mass and width,partial wave analysis are helpful to understand its structure. If it lies below the D*D1.threshold,molecule interpretation with JP=1.is favored,and JP=0-can not be ruled out. Otherwise Z+(443.)may be a virtual state with JP=2-. The analogous heavy flavor mesons Z+bb and Z++bc are considered as well,and the masses predicted in our model are in agreement with the predictions from the potential model and QCD sum rule.

关键词： nonrelativistic quark model hadronic molecule coupled-channel analysis

A new approximating method for Holstein model

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Science china({1.,Mechanics & Astronomy) 2010年第1期53卷 44-48页

作者： REN XueZao 1., LIAO Xu 1., LI Lei 1.& WANG KeLin 2 1.School of Science, Southwest university of Science and {1., Mian Yang 621.1., china 2 {3. of modern physics, university of Science and {1. of china, hefei 230026, china 1. School of Science Southwest University of Science and Technology Mian Yang 621010 China2. Department of Modern Physics University of Science and Technology of China Hefei 230026 China

A new approach-the method of coherent state orthogonal expansion is developed for one-dimensional Holstein model. In zeroth order approximation, the formula of ground state energy is deduced analytically and the solutions in strong- and weak-coupling limits are obtained correctly. When the trial wave-function of ground state is expanded to the second order, the obtained ground state energy agrees quite well with that calculated by numerical method in all coupling regimes. The present approach can be easily generalized to the situations of higher dimensions and more electrons.

关键词： coherent-state orthogonal expansion polaron simulated annealing method