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A modified multi-reference second order perturbation theory

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中国科学：化学英文版 2010年第4期53卷 933-939页

作者： LI AnYang1, HAN Huixian2. SUO BingBing3, WANG YuBin3 & WEN ZhenYi3 1institute of Computational Chemistry, Chongqing University of Post and Telecommunications, Chongqing 400065, china 2.epartment of {2., Northwest University, xi’ an 710069, china 3institute of modern physics, Northwest University, xi’ an 710069, china institute of Computational Chemistry Chongqing University of Post and Telecommunications Chongqing China Department of physics Northwest University Xi’ an China institute of modern {2. Northwest University Xi’ an China

A new scheme with extended model space is proposed to improve the calculation of multi-reference second order perturbation theory (MRPT2.. The new scheme preserves the concise code structure of the original program, and avoids intruder states in constructions of the potential energy surface, which is confirmed by a series of comparable calculations. The new MRPT2.program is an available tool for the research of molecular excited states and electronic spectrum.

关键词： perturbation theory multi-reference intruder state

Pairwise entanglement and local polarization of Heisenberg model

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Science china(physics,Mechanics & Astronomy) 2008年第10期51卷 1515-1522页

作者： xi xiaoQiang1,2. ZHANG Tao3, YUE RuiHong3,4 & LIU WuMing2.1 Department of Applied Mathematics and physics, xi’an institute of Post and Telecommunications, xi’an 710061,{2. 2.Beijing National Laboratory for Condensed Matter physics, institute of physics, Chinese Academy of Sciences, Beijing 100080,{2. 3 institute of modern physics, Northwest University, xi’an 710069,{2. 4 Department of physics, Ningbo University, Ningbo 3152.1,{2. Department of Applied Mathematics and physics Xi’an Institute of Post and Telecommunications Xi’an China Beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing China institute of modern {2. Northwest University Xi’an China Department of physics Ningbo University Ningbo China

The characteristics of pairwise entanglement and local polarization (LP) are dis-cussed by studying the ground state (states) of the Heisenberg XX model. The re-sults show that: the ground state (states) is (are) composed of the micro states with the minimal polarization (0 for even qubit and 1/2.for odd qubit); LP and the prob-ability of the micro state have an intimate relation, i.e. the stronger the LP, the smaller the probability, and the same LP corresponds to the same probability; the pairwise entanglement of the ground state is the biggest in all eigenvectors. It is found that the pairwise entanglement is decreased by the state degeneracy and the system size. The concurrence approaches a fixed value of about 0.3412.(for odd-qubit chain) or 0.3491 (for even-qubit chain) if the qubit number is large enough.

关键词： Heisenberg XX model local polarization pairwise entanglement

X-ray spectra induced in highly charged 40Ar^q+ interacting with Au surface

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 203-212页

作者： ZHANG xiao’an1,2. xiAO Guoqing1, YANG Zhihu1, CHEN ximeng3, ZHAO Yongtao1, LI Fuli4, ZHANG Yinping1, CUI Ying3, ZHANG Hongqiang3, XU Xu3, SHAO Jianxiong3 & ZHAN Wenlong11. institute of modern {2., Chinese Academy of Sciences, Lanzhou 730000, china 2. Department of {2., xianyang Normal University, xianyang 712.00, china 3. Department of modern {2., Lanzhou University, Lanzhou 730000, china 4. Department of Applied {2., xi’an Jiaotong University, xi’an 710049, china institute of modern {2. Chinese Academy of Sciences Lanzhou 730000 China

By use of optical spectrum technology, the spectra of X-ray induced by highly charged 40Arq+ ions interacting with Au surface have been studied. The results show that the argon Kα X-ray were emitted from the hollow atoms formed below the surface. There is a process of multi-electron exciting in neutralization of the Ar16+ion, with electronic con-figuration 1s2.in its ground state below the solid surface. The yield of the projectile Kα X-ray is related to its initial electronic configuration, and the yield of the target X-ray is related to the projectile kinetic energy.

关键词： highly charged ion hollow multi-electron excitation X- ray.

Parameter Estimation of Sub-/Super-synchronous Oscillation Based on Interpolated All-phase Fast Fourier Transform with Optimized Window Function

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Journal of modern Power Systems and Clean Energy 2024年第4期12卷 1031-1041页

作者： Bo Sun xi Wu xi Chen Zixiao Zou Qiang Li Bixing Ren School of Electrical Engineering Southeast UniversityNanjingChina State Grid Jiangsu Electric Power Company Limited Research institute NanjingChina

In recent years,with increasing amounts of renew-able energy sources connecting to power grids,sub-/super-syn-chronous oscillations(SSOs)occurred more *** to the time-variant nature of SsO magnitudes and frequencies,as well as the mutual interferences among SsO modes with close frequencies,the accurate parameter estimation of SsO has be-come a particularly challenging *** solve this issue,this paper proposes an improved spectrum analysis method by im-proving the window function and a spectrum correction method to achieve higher ***,by aiming at the sidelobe characteristics of the window function as evaluation criteria,a combined cosine function is optimized using a genetic algorithm(GA).Furthermore,the obtained window function is self-con-volved to extend its excellent characteristics,which have better performance in reducing mutual interference from other SSO ***,a new form of interpolated all-phase fast Fourier transform(IpApFFT)using the optimized window func-tion is proposed to estimate the parameters of *** meth-od allows for phase-unbiased estimation while maintaining algo-rithmic simplicity and *** performance of the pro-posed method is demonstrated under various conditions,com-pared with other estimation *** results vali-date the effectiveness and superiority of the proposed method.

关键词： Sub-/Super-synchronous oscillation(SSO) window function parameter estimation interpolated all-phase fast Fourier transform(ApFFT)

X-ray spectra induced by ^(12.)Xe^(q+) impacting the metal surface

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Science china(physics,Mechanics & Astronomy) 2008年第1期51卷 82-89页

作者： ZHANG xiaoAn 1,2.,xiAO GuoQing 1 ,YANG ZhiHu 1 ,CHEN xiMeng 3 ,ZHAO YongTao 1 , LI FuLi 4 ,WANG Li 1,2.,CUI Ying 3 ,ZHANG HongQiang 3 &ZHAN WenLong 1 1institute of modern {2.,Chinese Academy of Sciences,Lanzhou 730000,china 2.epartment of {2.,xianyang Normal University,xianyang 712.00,china 3Department of modern {2.,Lanzhou University,Lanzhou 730000,china 4Department of Applied {2.,xi’an Jiaotong University,xi’an 710049,china institute of modern {2. Chinese Academy of Sciences Department of physics Xianyang Normal University

Using the slow highly charged ions 12. Xe q+ (q=2.,2.,2.;initial kinetic T0≤4.65 keV/a.u.)to impact Au surface,the Au atomic Mαcharacteristic X-ray spectrum is *** result shows that as long as the charge state of projectile is high enough,the heavy atomic characteristic X-ray can be effectively excited even though the incident beam is very weak(nA magnitude),and the X-ray yield per ion is in the order of 10-8and increases with the kinetic energy and potential energy of *** measuring the Au Mα-X-ray spectra,Au atomic N-level lifetime is estimated at about 1.33×10-18s based on Heisenberg uncertainty relation.

关键词： slow highly charged ions characteristic X-ray level lifetime

Doubly contracted CI method and applications

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Science china Chemistry 2004年第4期47卷 276-282页

作者： WANG Yubin1, HAN Huixian1, ZHAI Gaohong2.,SUO Bin1 & WEN Zheny1,2.1. institute of modern {2., Northwest University, xian 710069, china 2. Laboratory of Physico-Inorganic Chemistry, Department of Chemistry, Northwest University, xian 710069,china Correspondence should be addressed to Wen Zhenyi institute of modern {2. Northwest University Xian China Laboratory of Physico-Inorganic Chemistry Department of Chemistry Northwest University Xi’an China

Based on the hole-particle correspondence an approximate so-called doubly contracted CI scheme is proposed. Examples calculated based on the doubly contracted CI (DCCI) scheme show that the number of configurations after contraction is reduced by three orders of magnitude, and the computation time is reduced by an order of magnitude. The examples also show that compared with experiments the DCCI and uncontracted CI have similar and reasonable accuracy to some spectroscopic parameters.

关键词： doubly contracted CI hole-particle symmetry approximate MRCI

A new method to solve the Reynolds equation including mass-conserving cavitation by physics informed neural networks(PINNs)with both soft and hard constraints

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Friction 2024年第6期12卷 1165-1175页

作者： Yinhu xi Jinhui DENG Yiling LI School of Mechanical Engineering Anhui University of Science and TechnologyHuainan 232001China Ericsson AB Datalinjen 3Linköping 58330Sweden

In this work,a new method to solve the Reynolds equation including mass-conserving cavitation by using the physics informed neural networks(PINNs)is *** complementarity relationship between the pressure and the void fraction is *** are several difficulties in problem solving,and the solutions are ***,the difficulty for considering the pressure inequality constraint by PINNs is solved by transferring it into one equality constraint without introducing *** the void fraction inequality constraint is considered by using the hard constraint with the max-min ***,to avoid the fluctuation of the boundary value problems,the hard constraint method is also utilized to apply the boundary pressure values and the corresponding functions are ***,for avoiding the trivial solution the limitation for the mean value of the void fraction is *** results are validated against existing data,and both the incompressible and compressible lubricant are *** agreement can be found for both the domain and domain boundaries.

关键词： Reynolds equation mass-conserving cavitation physics informed neural networks hard constraints trivial solution

The characteristic spectral lines of target atoms in the impact of^(40)Ar^(q+)ions on metal surfaces

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Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 729-736页

作者： ZHANG xiao’an1,2.ZHAO Yongtao1,2.LI Fuli1,YANG Zhihu2.xiAO Guoqing2.& ZHAN Wenlong2.1.Department of Applied physics,xi’an Jiaotong University,xi’an 710049,china 2.{2. of modern physics,Chinese Academy of Sciences,Lanzhou 730000,china Department of Applied physics Xi'an Jiaotong University Xi'an 710049 China institute of modern {2. Chinese Academy of Sciences Lanzhou 730000 China

We report the measured results of the 2.0 nm—1000 nm characteristic spectral lines of target atoms when highly charged ions40Ar q+(6≤q≤14) with the same kinetic energy and40Ar6+ with different kinetic energies are incident upon Al, Ti, Ni, Ta and Au surfaces, respectively. The results for12.Xe6+,12.Xe10+ and12.Xe15+ with the same kinetic energy (150 keV) incident upon a Ta surface are also reported. These results show that when the projectile and target are properly selected (40Ar12. impinges on Al,12.Xe6+ impinges on Ta), the spectral intensity of characteristic spectral lines of the target atom is effectively enhanced, and is not strongly dependent on the kinetic energy of the incident ions.

关键词： highly charged ion, hollow atom, characteristic spectrum, spectral intensity.

Two-dimensional simulation of Poiseuille-Rayleigh-Bénard flows in binary fluids with Soret effect

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Progress in Natural Science:Materials International 2007年第12期17卷 1389-1396页

作者： Hu Jun1 and Yin xieyuan2.1. institute of Applied physics and Computational Mathematics, Beijing 100088,{2. 2. Department of modern Mechanics, University of Science and Technology of{2., Hefei 2.002.,{2.) institute of Applied physics and Computational Mathematics Beijing 100088 China Department of modern Mechanics University of Science and Technology of China Hefei 230027 China

Poiseuille-Rayleigh-Bénard flows in binary fluids with Soret effect are directly simulated by a mixed finite element method. A temperature perturbation is used as an initial disturbed source for the basic parallel flows. The whole spatio-temporal evolution of the binary fluid flows is exhibited: initially only the disturbed mode with the wavenumber k=π is amplified while others are damped, and continuously the amplified mode grows further and the nonlinear effect becomes important; after a nonlinear evolution transition the flow system evolves finally into a periodic right traveling wave.

关键词： Poiseuille-Rayleigh-Bénard flow Soret effect through-flow.