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Communications in Theoretical Physics 2020年第11期72卷 104-108页

作者： Jie Yao Yanting Wang CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of Sciences55 East Zhongguancun RoadPO Box 2735Beijing100190 China School of Physical Sciences University of Chinese Academy of Sciences19A Yuquan RoadBeijing 100049China

A classical particle system coupled with a thermostat driven by an external constant force reaches its steady state when the ensemble-averaged drift velocity does not vary with *** this work,the statistical mechanics of such a system is derived solely based on the equiprobability and ergodicity principles,free from any conclusions drawn on equilibrium statistical mechanics or local equilibrium *** momentum space distribution is determined by a random walk argument,and the position space distribution is determined by employing the equiprobability and ergodicity *** expressions for energy,entropy,free energy,and pressures are then deduced,and the relation among external force,drift velocity,and temperature is also ***,the relaxation towards its equilibrium is found to be an exponentially decaying process obeying the minimum entropy production theorem.

关键词： nonequilibrium steady state constant external force dissipation statistical mechanics

A New Dynamical Evolutionary Algorithm Based on statistical mechanics

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Journal of Computer Science & Technology 2003年第3期18卷 361-368页

作者：李元香邹秀芬康立山 Zbigniew Michalewicz Software Engineering Laboratory Wuhan University Wuhan 430072 P.R. China Computer Science Department University of North Carolina at Charlotte Charlotte NC 28223-0001 USA

In this paper, a new dynamical evolutionary algorithm (DEA) is presented basedon the theory of statistical mechanics. The novelty of this kind of dynamical evolutionary algorithmis that all individuals in a population (called particles in a dynamical system) are running andsearching with their population evolving driven by a nev selecting mechanism. This mechanismsimulates the principle of molecular dynamics, which is easy to design and implement. A basictheoretical analysis for the dynamical evolutionary algorithm is given and as a consequence twostopping criteria of the algorithm are derived from the principle of energy minimization and the lawof entropy increasing. In order to verify the effectiveness of the scheme, DEA is applied to solvingsome typical numerical function minimization problems which are poorly solved by traditionalevolutionary algorithms. The experimental results show that DEA is fast and reliable.

关键词： dynamical evolutionary algorithm statistical mechanics stopping criterion dynamical system

statistical mechanics Model of Liquid Binary Ailoy

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Rare Metals 1994年第4期13卷 251-257页

作者：樊成才王俭钱嘉裕

From the view of chemical short range order and uncomplete random mixing existing in liquid binary al-loy, absorbing the rational part of past statistical mechanics model. a statistical mechanics model of liquidbinary... 详细信息

关键词： statistical mechanics Binary alloy

Recent Advances in the Use of statistical mechanics to Establish Molecular Thermodynamic Models for Electrolyte Solutions

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Tsinghua Science and Technology 2004年第4期9卷 444-454页

作者：李以圭 Department of Chemical Engineering Tsinghua UniversityBeijing 100084 China

Based on statistical mechanics, a review of recent theoretical studies of real electrolyte solutions is presented from three aspects, namely, molecular simulation, mean spherical approximation (MSA), and perturbation theory. Recent advances in studies of three kinds of electrostatic potentials of mean force, three kinds of internal energies (ion-ion, ion-dipole, and dipole-dipole interactions), and three kinds of electro-lyte models (primitive, non-primitive, and solvent primitive models) are introduced. The advantages and dis-advantages between primitive and non-primitive models, and between MSA and perturbation theory are dis-cussed. Some new equations of state (EOSs) based on MSA and perturbation theory for real electrolyte so-lutions are introduced. The one-Yukawa EOS and the two-Yukawa EOS for charged colloid systems are presented.

关键词： statistical mechanics electrolyte solutions molecular simulation perturbation theory mean spherical approximation primitive and non-primitive models equation of state

Physical Chemistry: statistical mechanics

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statistical-mechanical analysis of multiuser channel capacity with imperfect channel state information

2006年

作者： Horia Metiu

ISBN: (数字)9781000065275

ISBN: (纸本)9780815340850

Physical Chemistry is a new undergraduate textbook by Horia Metiu published as four separate paperback volumes. These four volumes combine a clear and thorough presentation of the theoretical and mathematical aspects of the subject with examples and applications drawn from current industrial and academic research. By using the computer to

关键词： statistical mechanics

来源：畅想之星图书光盘版（南... 畅想之星图书光盘版（南... 评论

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Chinese Physics B 2008年第12期17卷 4451-4457页

作者：汪辉松曾贵华 The State Key Laboratory on Fiber-Optical Local Area Networks and Advanced Optical Communication Systems Electronic Engineering Department Shanghai Jiaotong University

In this paper, the effect of imperfect channel state information at the receiver, which is caused by noise and other interference, on the multi-access channel capacity is analysed through a statistical-mechanical approach. Replica analyses focus on analytically studying how the minimum mean square error （MMSE） channel estimation error appears in a multiuser channel capacity formula. And the relevant mathematical expressions are derived. At the same time, numerical simulation results are demonstrated to validate the Replica analyses. The simulation results show how the system parameters, such as channel estimation error, system load and signal-to-noise ratio, affect the channel capacity.

关键词： statistical mechanics channel capacity minimum mean square error channel estimation code division multiple access (CDMA)

A universal function of creep rate

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Chinese Physics B 2015年第9期24卷 5-10页

作者：李菁田荣曦明王建录张邦强宁西京 Institute of Modern Physics Department of Nuclear Science and TechnologyFudan University Department of Optical Science and Engineer Fudan University Dongfang Turbine Co. Ltd.

In this paper, we derive a universal function from a model based on statistical mechanics developed recently, and show that the function is well fitted to all the available experimental data which cannot be described by any function previously established. With the function predicting creep rate, it is unnecessary to consider which creep mechanism dominates the process, but only perform several experiments to determine the three constants in the function. It is expected that the new function would be widely used in industry in the future.

关键词： creep statistical mechanics metal and alloys

Evaporative cooling of ^(87)Rb atoms into Bose-Einstein condensate in an optical dipole trap

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Chinese Optics Letters 2010年第7期8卷 627-629页

作者：熊德智王鹏军付正砷柴世杰张靖 State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Opto-ElectronicsShanxi University

We create a Bose-Einstein condensate （BEC） of 87Rb atoms by runaway evaporative cooling in an optical trap. Two crossed infrared laser beams with a wavelength of 1064 nm are used to form an optical dipole trap. After precooling the atom samples in a quadrupole-Ioffe configuration （QUIC） trap under 1.5 #K by radio-frequency （RF） evaporative cooling, the samples are transferred into the center of the glass cell, then loaded into the optical dipole trap with 800 ms. The pure condensate with up to 1.5× 10^5 atoms is obtained over 1.17 s by lowering the power of the trap beams.

关键词： Cooling Evaporation Evaporative cooling systems Infrared lasers Rubidium statistical mechanics Steam condensers

Optimizing the atom types of proteins through iterative knowledge-based potentials

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Chinese Physics B 2018年第2期27卷 43-50页

作者：汪心享黄胜友 School of Physics Huazhong University of Science and Technology

Knowledge-based scoring functions have been widely used for protein structure prediction, protein-small molecule, and protein-nucleic acid interactions, in which one critical step is to find an appropriate representation of protein structures. A key issue is to determine the minimal protein representations, which is important not only for developing of scoring func- tions but also for understanding the physics of protein folding. Despite significant progresses in simplifying residues into alphabets, few studies have been done to address the optimal number of atom types for proteins. Here, we have investigated the atom typing issue by classifying the 167 heavy atoms of proteins through 11 schemes with 1 to 20 atom types based on their physicochemical and functional environments. For each atom typing scheme, a statistical mechanics-based iterative method was used to extract atomic distance-dependent potentials from protein structures. The atomic distance-dependent pair potentials for different schemes were illustrated by several typical atom pairs with different physicochemical proper- ties. The derived potentials were also evaluated on a high-resolution test set of 148 diverse proteins for native structure recognition. It was found that there was a crossover around the scheme of four atom types in terms of the success rate as a function of the number of atom types, which means that four atom types may be used when investigating the basic folding mechanism of proteins. However, it was revealed by a close examination of typical potentials that 14 atom types were needed to describe the protein interactions at atomic level. The present study will be beneficial for the development of protein related scoring functions and the understanding of folding mechanisms.

关键词： atom types knowledge-based potentials statistical mechanics iteration

Application of Corner Transfer Matrix Renormalization Group Method to the Correlation Function of a Two－Dimensional Ising Model ＊

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Chinese Physics Letters 2003年第11期20卷 2004-2007页

作者：何春山李志兵 DepartmentofPhysics ZhongshanUniversityGuangzhou510275

The correlation function of a two-dimensional Ising model is calculated by the corner transfer matrix renormalization group method. We obtain the critical exponent η = 0.2496 with few computer resources.

关键词： statistical mechanics