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Comparison of perturbation theory and Mean Spherical Approximation Based on Molecular Simulation Data

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Chinese Journal of Chemical Engineering 1999年第1期7卷 10-19页

作者：刘文彬李以圭陆九芳 Tsing Hua Univ Dept Chem Engn Beijing 100084 Peoples R China

A comprehensive study on various internal energies for the dipolar hard sphere fluids, including Stockmayer fluids, the mixtures of Lennard-Jones and Stockmayer and Stockmayer fluids and the electrolyte solutions is reported based on the perturbation theory and mean spherical approximation. Compared with the results of molecular simulations, it is shown that the perturbation theory is better than the mean spherical approximation.

关键词： perturbation theory mean spherical approximation molecular simulation internal energies

Characteristics of spectral-hole burning in Tm^(3+):YAG based on the perturbation theory

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Chinese Physics B 2014年第6期23卷 37-43页

作者：张世宇马秀荣张双根陈雷王夏洋穆宽林王松 Engineering Research Center on Communication Devices (Ministry of Education) School of Computer and Communication EngineeringTianjin University of Technology Tianjin Key Laboratory of Film Electronic and Communication Device School of Electronic Information EngineeringTianjin University of Technology

In this paper, the physical mechanism of the interaction between electromagnetic wave and spectral-hole burning crystal material is investigated in detail. In the small signal regime, a perturbation theory model is used to analyze the mechanism of spectral-hole burning. By solving the Liouville equation, three-order perturbation results are obtained. From the theoretic analysis, spectral-hole burning can be interpreted as a photon echo of the zero-order diffraction echo when the first optical pulse and the second optical pulse are overlapped in time. According to the model, the spectral-hole width is dependent on the chirp rate of the reading laser. When the chirp rate is slow with respect to the spectral features of interest, the spectral hole is closely mapped into time domain. For a fast chirp rate, distortions are observed. The results follow Maxwell-Bloch model and they are also in good agreement with the experimental results.

关键词： perturbation theory spectral-hole burning photon echo

A novel algorithm for evaluating cement azimuthal density based on perturbation theory in horizontal well

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Petroleum Science 2024年第1期21卷 244-251页

作者： Ji-Lin Fan Feng Zhang Qian Chen Hao-Chen Song Lu-Yu Zhong Yue-Xiang Dai National Key Laboratory of Deep Oil and Gas School of GeosciencesChina University of Petroleum(East China)Qingdao 266580ShandongChina China National Logging Corporation Xi'an 710076ShaanxiChina Sinopec Matrix Corporation Qingdao 266001ShandongChina

Cement density monitoring plays a vital role in evaluating the quality of cementing projects,which is of great significance to the development of oil and ***,the presence of inhomogeneous cement distribution and casing eccentricity in horizontal wells often complicates the accurate evaluation of cement azimuthal *** this regard,this paper proposes an algorithm to calculate the cement azimuthal density in horizontal wells using a multi-detector gamma-ray detection *** spatial dynamic response functions are simulated to obtain the influence of cement density on gamma-ray counts by the perturbation theory,and the contribution of cement density in six sectors to the gamma-ray recorded by different detectors is obtained by integrating the spatial dynamic response *** with the relationship between gamma-ray counts and cement density,a multi-parameter calculation equation system is established,and the regularized Newton iteration method is employed to invert casing eccentricity and cement azimuthal *** approach ensures the stability of the inversion process while simultaneously achieving an accuracy of 0.05 g/cm^(3) for the cement azimuthal *** accuracy level is ten times higher compared to density accuracy calculated using calibration ***,this algorithm enhances the accuracy of cement azimuthal density evaluation,provides valuable technical support for the monitoring of cement azimuthal density in the oil and gas industry.

关键词： Cement azimuthal density perturbation theory Casing eccentricity Spatial dynamic response function Regularized Newton iteration

Covariant perturbation theory of Non—Abelian Kinetic theory

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Chinese Physics Letters 2002年第1期19卷 23-25页

作者：郑小平李家荣 IstituteofParticlePhysics HuazhongNormalUniversityWuhan430079

A ``double perturbation'' theory is presented in the framework of the kinetic theory of quark-gluon plasma. A solvable set of equations from the double perturbation are derived and proven to be gauge invariant. The La... 详细信息

关键词： Quark matter perturbation theory Landau damping Convergent Series Plasmon correlators perturbation Kinetic theory DOUBLE

On the performance of the open-shell perturbation theory

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Science China Chemistry 2011年第3期54卷 446-453页

作者： CHEN FeiWu WEI MeiJu LIU WenJian Department of Chemistry University of Science and Technology Beijing Beijing 100083 China Beijing National Laboratory for Molecular Sciences Institute of Theoretical and Computational Chemistry State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

A few open-shell molecules are taken as examples in order to examine the performance of the open-shell perturbation theory for electron correlation(J Chem theory Comput,2009,5:931–936).The convergence of the perturbation series is shown to be stable for the doublet state of NH2 at both the equilibrium and stretched *** equilibrium bond lengths,and harmonic and anharmonic vibrational frequencies are calculated for NO(X2),OH(X2),CH(X2)and NH(X2)with different second-order perturbation theories at the cc-pVDZ,cc-pVTZ and cc-pVQZ *** ground state energies of BeF(X2+), MgH(X2+)and the HCCl triplet state have also been computed with various perturbation theories and compared with configuration interaction with single and double excitations(CISD)and CISD+Davidson *** energy difference between the formaldehyde(H2CO + )and hydroxymethylene(HCOH+)radical cations has been *** perturbation theory predicts correctly that H2CO + is more stable than HCOH+.However,calculations using UMP2,CASPT2,the Z-averaged perturbation theory and restricted Mφller–Plesset theory fail even to produce the correct sign of the energy difference.

关键词： open shell perturbation theory convergence bond length harmonic vibrational frequency

Derivation of Martin-Hou Equation of State from Hard-particle perturbation theory

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Chemical Research in Chinese Universities 2000年第1期16卷 49-56页

作者： ZHANG Bing-jian (Department of Chemistry, Zhejiang University, Hangzhou 310027, P. R. China) HOU Yu-chun (Department of Chemical Engineering, Zhejiang University, Hangzhou 310027, P. R. China) Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China Zhejiang Univ Dept Chem Engn Hangzhou 310027 Peoples R China

In this paper, the Martin-Hou equation of state is derived by using a power series representation of radial distribution function and an analytic representation of multi-section potential based on the Barker-Henderson hard-particle perturbation theory including high-order terms. In the derivation, a theoretical form of Martin-Hou equation was obtained. It had a similar form and the same capability to predict P-V-T properties as the Martin-Hou equation and no additional data were required for evaluating the constants. The characteristic constants of the theoretical expression have certain relationships with the molecular parameters.

关键词： perturbation theory Martin-Hou equation of state Theoretical expression P-V-T properties Molecular parameter

Three Types of Expression in Dark-Soliton perturbation theory Based on Squared Jost Solutions

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Communications in Theoretical Physics 2007年第1期47卷 15-18页

作者： AO Sheng-Mei YAN Jia-Ren College of Physics and Information Science Hunan Normal University Changsha 410081 China

Three types of expression in the dark-soliton perturbation theory based on squared Jost solutions are invesgigaged in ghis paper. It is shown that there are three formally different results about the effects of perturbagion on a dark soliton, and it is proved by means of a transformation between two integral variables that they are essentially equivalent.

关键词： dark soliton perturbation theory squared Jost solution soliton velocity first-order correction

Investigation of Bose-Einstein Condensates in q-Deformed Potentials with First Order perturbation theory

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Communications in Theoretical Physics 2018年第2期69卷 154-158页

作者： Ferhat Nutku Ekrem Ayd?ner Department of Physics Faculty of Science istanbul University Vezneciler istanbul 34134 Thrke

The Gross-Pitaevskii equation, which is the governor equation of Bose-Einstein condensates, is solved by first order perturbation expansion under various q-deformed potentials. Stationary probability distributions reveal one and two soliton behavior depending on the type of the q-deformed potential. Additionally a spatial shift of the probability distribution is found for the dark soliton solution, when the q parameter is changed.

关键词： Bose-Einstein condensates solitons q-deformed potential perturbation theory

Practical 0-stability of stochastic differential equations and corresponding stochastic perturbation theory

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Practical 0-stability of stochastic differential equations...