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Entropy product measure for multipartite pure states

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Science china(physics,Mechanics & Astronomy) 2006年第5期49卷 606-615页

作者： CAO Wancang1,2. LIU Dan2. PAN Feng3 & LONG Guilu2.4 1. Department of physics, Chifeng college, Chifeng 02.001, {2. 2. Key Laboratory for Quantum Information and Measurements, Department of physics, Tsinghua university, Beijing 100084, {2. 3. Department of physics, Liaoning Normal university, Dalian 11602., {2. 4. Key Laboratory for Atomic and Molecular Nano-Sciences, Tsinghua university, Beijing 100084, {2. Correspondence should be addressed to Long Guilu Department of physics Chifeng College Chifeng 024001 China Key Laboratory for Quantum Information Measurements Department of Physics Tsinghua University Beijing 100084 China Department of physics Liaoning Normal University Dalian 116029 China Key Laboratory for Atomic Molecular Nano-Sciences Tsinghua University Beijing 100084 China

An entanglement measure for multipartite pure states is formulated using the product of the von Neumann entropy of the reduced density matrices of the constituents. Based on this new measure, all possible ways of the maximal entanglement of the triqubit pure states are studied in detail and all types of the maximal entanglement have been compared with the result of ‘the average entropy’. The new measure can be used to calculate the degree of entanglement, and an improvement is given in the area near the zero entropy.

关键词： multipartite pure state von Neumann entropy entanglement measure

Role of gallium wetting layer in high-quality ZnO growth on sapphire (0001) substrates

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Science china(physics,Mechanics & Astronomy) 2004年第5期47卷 612-620页

作者： ZENG Zhaoquan1,3, WANG Yong2. DU Xiaolong1, MEI Zengxia1, KONG Xianghe3, JIA Jinfeng1, XUE Qikun1 & ZHANG Ze2. 4 1. State Key Laboratory for Surface physics, Institute of physics, Chinese Academy of Sciences, Beijing 100080, {2. 2. Laboratory of Electron Microscopy, Institute of physics, Chinese Academy of Sciences, Beijing 100080, {2. 3. college of physics and Engineering, Qufu Normal university, Qufu 2.3165, {2. 4. Beijing university of Technology, Beijing 10002., {2. 1. State Key Laboratory for Surface physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 2. college of physics and Engineering Qufu Normal University 273165 Qufu China 3. Laboratory of Electron Microscopy Institute of Physics Chinese Academy of Sciences 100080 Beijing China 4. Beijing university of Technology 100022 Beijing China

A Ga wetting layer was used to modify the surface structure of sapphire (0001) substrate to prepare high-quality ZnO film by radio frequency plasma-assisted molecule beam epitaxy. We found that this Ga layer plays a crucial role in eliminating 30 rotation domains, controlling polarity and decreasing defect density in ZnO epilayers, as demonstrated by in situ reflection high energy electron diffraction, ex situ high resolution X-ray diffraction and high resolution cross-sectional transmission electron microscopy. Zn-polar film of ZnO was determined by convergent beam electron diffraction. A Ga bilayer model is proposed to understand the effects of the Ga wetting layer on high-quality ZnO growth.

关键词： Ga wetting layer, sapphire, polarity, defect density, zinc oxide, rf-MBE, RHEED, HRXRD, TEM, CBED.

Nonequilibrium solvation theory:Comparison,modification and application

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Chinese Science Bulletin 2003年第10期48卷 965-970页

作者： FU Kexiang1,2. LI Xiangyuan1 & ZHU Quan1 1. college of Chemical Engineering, Sichuan university, Chengdu 610065, {2. 2. college of physics, Sichuan university, Chengdu 610065, {2. college of Chemical Engineering Sichuan University Chengdu China college of physics Sichuan University Chengdu China

Faults existing in the current theories of non- equilibrium solvation have been clarified in this report. Based on a novel expression of solvation free energy for nonequilibrium, generalized formulations of solvent reor- ganization energy for electron transfer and of solvation shift for spectrum have been established. Furthermore, a new form of solvent reorganization energy for electron transfer in two-sphere case, which greatly differs from the one by Mar- cus, has been deduced. A single-sphere model for solvation shift of spectrum has been put forward both by deducing the generalized formulations and by showing the correct forms of self-energy of reaction field. It has been concluded that the current theories overestimate the solvent reorganization energy and the solvation shift by a factor of about 2. By apply- ing the models established, the discrepancies between the theory and experiments before have been perfectly explained.

关键词：非平衡溶剂理论修正应用电子转移溶剂重构能量反应场溶剂交换

Investigation of nano-talc as a filling material and a reinforcing agent in high density polyethylene (HDPE)

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Rare Metals 2006年第z1期25卷 422-425页

作者： CHEN Nanchun MA Lei ZHANG Tao Center for Material Engineering Guilin Institute of Technology Guilin 541004 China Key Laboratory of Nonferrous Materials and Processing Technology Ministry of Education Guilin Institute of Technology Guilin 541004 China Department of Physics and Information Technology Yulin Teachers'' College Yulin 537000 China Center for Material Engineering Guilin Institute of Technology Guilin 541004 China Key Laboratory of Nonferrous Materials and Processing Technology Ministry of Education Guilin Institute of Technology Guilin 541004 China

An experiment of producing high density polyethylene (HDPE) nano-composite filled with 4wt.% talc was presented. Acting as filler and a reinforcing agent in the HDPE, talc powder, sized at around 5 μm, was surface-treated with aluminum diethylene glycol dinitrate coupling agent before adding to the HDPE. Analyses of the reinforced HDPE nano-composite show significant improvement in its mechanical properties including, tensile strength (>2. MPa), break elongation (2. MPa), and friction coefficients<0.11. The results demonstrate that, after surface-treated, talc can be used as a promising filling material and a reinforcing agent in making HDPE nano-composite.

关键词： HDPE talc filling material reinforcing agent nano-composite mechanical properties

The new insights of hyperbaric oxygen therapy:focus on inflammatory bowel disease

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Precision Clinical Medicine 2024年第2期7卷 159-169页

作者： Leilei Chen Yan Wang Huihui Zhou Yi Liang Fengqin Zhu guangxi Zhou Cheeloo college of Medicine Shandong UniversityJinan 250012China Department of Gastroenterology Affliated Hospital of jining Medical University Jining Medical UniversityJining 272000China Department of Hyperbaric Oxygen Affliated Hospital of jining Medical UniversityJining Medical UniversityJining 272000China

Inflammatory bowel diseases(IBD),with an increasing incidence,pose a significant health *** there have been significant advances in the treatment of IBD,more progress is still *** oxygen therapy(HBOT)has been shown to treat a host of conditions such as carbon monoxide poisoning,decompression sickness,and gas *** the last few years,there has been an increase in research into the use of HBOT as an adjunct to conventional treatment for *** research has shown that HBOT may exert its therapeutic effects by decreasing oxidative stress,inhibiting mucosal inflammation,promoting ulcer healing,influencing gut microbes,and reducing the incidence of IBD *** paper aims to provide a comprehensive review of experimental and clinical trials exploring HBOT as a supplement to IBD treatment strategies.

关键词： hyperbaric oxygen therapy inflammatory bowel disease mucosal inflammation

Direct CP violation in hadronic B decays

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2.& Lü Caidian3 1. Department of physics, Lishui university, Lishui 32.000,{2. 2. Department of physics, Shanghai Jiaotong university, Shanghai 2.0030, {2. 3. Institute of High Energy physics, Beijing 100049,{2. Department of physics Lishui University Lishui 323000 China Department of physics Shanghai Jiaotong University Shanghai 200030 China Institute of High Energy physics Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

Effect of an impurity on 3-electron quantum dots in magnetic fields

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Science china(physics,Mechanics & Astronomy) 2004年第5期47卷 521-530页

作者： LIU Yimin1,2. HUANG Gangming1 & BAO Chengguang1 1. Department of physics, Zhongshan university, Guangzhou 5102.5, {2. 2. Department of physics, Shaoguan university, Shaoguan 512.05, {2. 1. Department of physics Zhongshan University 510275 Guangzhou China 2. Department of physics Shaoguan University 512005 Shaoguan China

The ground-state property of a 2.dimensional 3-electron quantum dot (QD) subjected to an external magnetic fieldB and affected by an impurity is studied. The impurity is located at thez-axis by a distanced from the plane of the dot. The evolution of the angular momentumL o and the spinS o of the ground state in accordance withB andd has been calculated, and the results are summarized and plotted in a (L o,S o) diagram. The spatial distribution of the electrons (the size and the geometric features) and the optical absorption have also been investigated. The (L o S o) diagram indicates thatL o andS o may jump whend and/orB vary. It was found that, due to the constraints arising from symmetry, each symmetric geometry is accessible only to a specific group of states having specificL o andS o.

关键词： quantum dot, ground state, charged impurity, magnetic field.

The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & LIN Shenglu2.1. School of physics and Electronic Engineering, Yantai Normal university, Yantai 2.402., {2. 2. Department of physics, Shandong Normal university, Jinan 2.0014, {2. 1. School of physics and Electronic Engineering Yantai Normal University Yantai 264025 China 2. Department of physics Shandong Normal University Jinan 250014 China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

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, {2. 2. LAPC, Institute of Atmospheric physics, Chinese Academy of Sciences, Beijing 10002., {2. 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.