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Isospin-dependent relativistic microscopic optical potential in the Dirac Brueckner-Hartree-Fock method

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Science china(physics,Mechanics & Astronomy) 2004年第2期47卷 189-198页

作者： RONG Jian1 & MA Zhongyu1,2.3 1. china institute of Atomic Energy, Beijing 102.13, china 2. Center of Nuclear theoretical physics, National Laboratory of Heavy Ion Accelerator of Lanzhou, Lan-zhou 730000, china 3. institute of theoretical physics, chinese academy of sciences, Beijing 100080, china Correspondence should be addressed to Rong Jian (email: jrong@***) 1. china institute of Atomic Energy 102413 Beijing China 2. Center of Nuclear theoretical physics National Laboratory of Heavy Ion Accelerator of Lanzhou 730000 Lanzhou China 3. institute of theoretical {2. Chinese Academy of Sciences 100080 Beijing China

The relativistic microscopic optical potential in the asymmetric nuclear matter is studied in the framework of the Dirac Brueckner-Hartree-Fock method. A new decomposition of the Dirac structure of the nuclear self-energy in nuclear matter is adopted. The self-energy of a nucleon with E > 0 in nuclear matter is calculated with the G matrix in the Hartree-Fock approach. The optical potential of a nucleon in the nuclear medium is identified with the nucleon self-energy. The energy and asymmetric parameter dependence of the relativistic optical potentials for proton and neutron are discussed. The resulting Schroedinger equivalent potentials have reasonable behaviors of the energy dependence. The asymmetric parameter dependence of relativistic optical potentials and Schroedinger potentials are emphasized.

关键词： Dirac Brueckner Hartree-Fock, relativistic microscopic optical potential, asymmetric nuclear matter, isospin-dependence.

Anomalous dielectric behavior in nanocrystalline γ-Fe_2._3

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chinese Science Bulletin 1999年第2期44卷 186-189页

作者： YE Xisheng , SHA Jian , CHEN Bin , JIAO Zhengkuan ZHANG LideDepartment of physics, Zhejiang University, Hangzhou 31002., china Northwest {2. of Nuclear Technology, Xi’ an 71002., china {2. of theoretical physics, chinese academy of sciences, Beijing 100080, china {2. of Solid State physics, chinese academy of sciences, Hefei 2.0031, china Department of physics Zhejiang University Hangzhou China Northwst institute of Nuclear Technology Xi’an China institute of theoretical {2. Chinese Academy of Sciences Beijing China institute of Solid State physics Chinese Academy of Sciences Hefie China

The measurements of electric capacities and dielectric loss angles for nanocrystalline yFe2.3 under air and vacuum atmospheres have been conducted by using ac LRC method, and the conductivity and the polarization rela... 详细信息

The measurements of electric capacities and dielectric loss angles for nanocrystalline yFe2./sub>O3 under air and vacuum atmospheres have been conducted by using ac LRC method, and the conductivity and the polarization relaxation time have also been calculated from the frequency spectra of real and imaginary parts of the dielectric constants. The anomalous dielectric behavior implies the existence of two kinds of polarization mechanisms with different relaxation times, which are caused by the defects and the dangling bonds in the interfaces, respectively. The experimental and calculated results indicated that the polarization loss and the conductance loss are dominant in air atmosphere and vacuum, respectively.

关键词： nanocrystalline γ-Fe2.3 dielectric behavior polarization mechanism.

Challenges in the theoretical investigations of lipid membrane configurations

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chinese physics B 2013年第2期22卷 36-44页

作者：涂展春 Department of physics Beijing Normal University Kavli institute for theoretical {2. china Chinese Academy of Sciences

We report some key results in the theoretical investigations of configurations of lipid membranes and present several challenges in this field,which involve（i）the exact solutions to the shape equation of lipid vesicles,（ii）the exact solutions to the governing equations of open lipid membranes,（iii）the neck condition of two-phase vesicles in the budding state,（iv） the nonlocal theory of membrane elasticity,and（v）the relationship between the symmetry and the magnitude of the free energy.

关键词： configuration lipid membrane

Two mode photon bunching effect as witness of quantum criticality in circuit QED

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Science china(physics,Mechanics & Astronomy) 2009年第12期52卷 1898-1905页

作者： AI Qing1,WANG YingDan2.LONG GuiLu1,3 & SUN ChangPu4 1 Department of physics,Tsinghua University,Beijing 100084,china 2.Department of physics,University of Basel,Klingelbergstrasse 82.4056 Basel,Switzerland 3 Tsinghua National Laboratory for Information Science and Technology,Beijing 100084,china 4 institute of theoretical physics,chinese academy of sciences,Beijing 100080,china 1. Department of physics Tsinghua University Beijing 100084 China 2. Department of physics University of Basel Klingelbergstrasse 82 4056 Basel Switzerland 3. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China 4. institute of theoretical {2. Chinese Academy of Sciences Beijing 100080 China

We suggest a scheme to probe critical phenomena at a quantum phase transition (QPT) using the quantum correlation of two photonic modes simultaneously coupled to a critical system. As an experimentally accessible physical implementation,a circuit QED system is formed by a capacitively coupled Josephson junction qubit array interacting with one superconducting transmission line resonator (TLR). It realizes an Ising chain in the transverse field (ICTF) which interacts with the two magnetic modes propagating in the TLR. We demonstrate that in the vicinity of criticality the originally independent fields tend to display photon bunching effects due to their interaction with the ICTF. Thus,the occurrence of the QPT is reflected by the quantum characteristics of the photonic fields.

关键词： quantum phase transition photon bunching circuit QED

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2. HU Fei2.& ZHU Jiang2.1. College of Environmental sciences, Peking University, Beijing 100871, china 2. LAPC, {2. of Atmospheric physics, chinese academy of sciences, Beijing 10002., china 1. College of Environmental sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Ambient noise near the sea-route

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Science china(physics,Mechanics & Astronomy) 2009年第1期52卷 40-45页

作者： HE Li1,2. LI ZhengLin1,3 & PENG ZhaoHui1 1 National Laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, Beijing 100190, {2. 2.institute of Geology and Geophysics, chinese academy of sciences, Beijing 10002., {2. 3 NanHai Laboratory of Acoustics, institute of Acoustics, chinese academy of sciences, Haikou 5702.6, {2. National Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing 100190 China institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China NanHai Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Haikou 570206 China

Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

关键词： ambient noise model horizontal correlation discrete ships

A new principle of synthetic cascade utilization of chemical energy and physical energy

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Science china(Technological sciences) 2005年第2期48卷 163-179页

作者： JIN Hongguang1, HONG Hui1,2. WANG Baoqun1,2. HAN Wei1,2.& LIN Rumou1,2.1. institute of Engineering Thermophysics, {2., Beijing 100080, china 2. Graduate School of the {2., Beijing 100039, china 1. institute of Engineering Thermophysics Chinese Academy of Sciences 100080 Beijing China 2. Graduate School of the chinese academy of sciences 100039 Beijing China

We propose a new principle of the cascade utilization of both chemical energy and physical energy in energy systems with the integration of chemical processes and thermal cycles. Particularly, a general equation of energy levels of substance, Gibbs free energy of chemical reaction and physical energy is explicitly founded. On the basis of this equation, a chemical-looping combustion and an indirect combustion are investigated. Furthermore, a mechanism of energy release, with the combination of decreasing the energy level of Gibbs free energy and upgrading the energy level of low or middle- temperature thermal energy, is clarified. The promising results obtained here establish a theoretical basis for the further investigation of multi-function systems in which energy and the environment are compatible, and create a new approach to improve the performance of traditional thermal cycles.

关键词： chemical energy, cascade utilization, exergy, energy conversion.

Optimization of mathematical models for thematic maps

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Science china(Technological sciences) 2010年第S1期53卷 15-24页

作者： QI QingWen1,ZHANG An1,JIANG LiLi1,ZOU XiuPing2.XU Li3 & CHENG Xi1,4 1 institute of Geographical sciences and Natural Resources Research,{2.,Beijing 100101,china 2.institute of Policy and Management,{2.,Beijing 100080,china 3 Taishan University,Taian 2.102.,china 4 Graduate University of {2.,Beijing 100049,china chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Taishan Univ Tai An 271021 Shandong Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

The thematic map is a major class of maps designed to demonstrate particular features or concepts,functioning as an indispensable tool in geographical *** process of thematic mapping is one into which geographical research goes deeply and *** key activity and course of thematic map production is the use of mathematical models to create thematic data ***,the selection and optimization of mathematical models is in the forefront of thematic map *** theoretical foundations,mechanisms and methods of mathematical model optimization are expounded in this paper,including two approaches,the phase by phase mode and the multi-aim scheme balance *** studies in eco-environment mapping and emergency mapping are described and analyzed,with a hierarchical analysis method being used in the model optimization for eco-environment fragility and sensitivity assessment mapping in Beibuwan (Guangxi) District,the dynamic system (DS) method being used in the model optimization for ecological security adjustment mapping in Xishuang Banna,Yunnan province,and the multi-phase mode being used in the models for forest fire and infectious diseases mapping.

关键词： thematic map mathematic model optimization

Systematic study of survival probability of excited superheavy nuclei

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Science china(physics,Mechanics & Astronomy) 2011年第S1期54卷 109-113页

作者： XIA ChengJun1, SUN BaoXi1, ZHAO EnGuang2.3 & ZHOU ShanGui2.3 1College of Applied sciences, Beijing University of Technology, Beijing 10012., china 2.2. of theoretical physics, chinese academy of sciences, Beijing 100190, china 3Center of theoretical Nuclear physics, National Laboratory of Heavy Ion Accelerator, Lanzhou 730000, china chinese Acad Sci Inst Theoret Phys Beijing 100190 Peoples R China Beijing Univ Technol Coll Appl Sci Beijing 100124 Peoples R China Ctr Theoret Nucl Phys Natl Lab Heavy Ion Accelerator Lanzhou 730000 Peoples R China

The stability of excited superheavy nuclei (SHN) with 100 Z 134 against neutron emission and fission is investigated by using a statistical model. In particular, a systematic study of the survival probability against fission in the 1n-channel of these SHN is made. The present calculations consistently take the neutron separation energies and shell correction energies from the calculated results of the finite range droplet model which predicts an island of stability of SHN around Z = 115 and N = 179. It turns out that this island of stability persists for excited SHN in the sense that the calculated survival probabilities in the 1n-channel of excited SHN at the optimal excitation energy are maximized around Z = 115 and N = 179. This indicates that the survival probability in the 1n-channel is mainly determined by the nuclear shell effects.

关键词： survival probability superheavy elements island of stability neutron emission fission