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Using lightning locating system based on time-of-arrival technique to study three-dimensional lightning discharge processes

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Science china Earth Sciences 2010年第4期53卷 591-602页

作者： ZHANG GuangShu1,WANG YanHui1,QIE XiuShu2,ZHANG Tong1,ZHAO YuXiang1,3,LI YaJun1 & CAO DongJie11 Laboratory for Climate Environment and Disasters of Western china,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,china 2 Laboratory for Middle Atmosphere and Global Environment Observation(LAGEO),Institute of Atmospheric physics,Chinese Academy of Sciences,Beijing 100029,china 3 department of physics,tianshui normal college,tianshui 741001,china Laboratory for Climate Environment and Disasters of Western china Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China department of physics Tianshui Normal College Tianshui China

A time-of-arrival(TOA) system based on GPS technology for locating VHF radiation sources from lightning has been developed and used in observation sites in the northern Shandong Province,*** 3D images of the lightning progression have been obtained successfully for the first time in *** 3D-channel evolutions of typical negative CG,positive CG and IC lightning flashes have been discussed together with the data of fast electric field *** was found that significant differences existed between the negative and positive CG lightning flashes in terms of the initiation and propagation of the radiation *** preliminary breakdown of a negative CG lightning flash propagated at a speed about 5.2×104 m/*** stepped leader of negative CG lightning flashes was trigged by negative initial ***,it propagated downward at a speed of 1.3×105 m/*** initial process of the positive CG lightning flashes was also a propagation process of negative *** streamers propagated dominantly horizontally in the positive charge region and accumulated positive charges at the origin of the lightning,and as a consequence,initiated downward positive streamers.A new type of lightning discharge that was triggered by a narrow bipolar pulse(NBP) is discussed in this *** NBP was originated at altitude of about 10.5 km in the upper positive charge *** a distinct difference from normal IC flash,its channels extended horizontally all around and produced a lot of radiation *** source power of the NBP could approach 16.7 kW,which is much greater than that of normal lightning discharge ranging between 100 mW and 500 *** 3D propagation of this new type of lightning discharge was observed and obtained for the first time in *** possible initiation mechanism of this new type of light-ning is discussed here.

关键词： time-of-arrival(TOA) technique three dimensional lightning locating system discharge process narrow bipolar pulse new-type of IC lightning

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Synthesis, characterization, and biological activities of Pt(Ⅱ) and Pd(Ⅱ2',3',4',5,7-pentahydroxy flavone

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Rare Metals 2004年第1期23卷 38-42页

作者： TANGHui＇An WANGXiaofang YANGSheng WANGLiufang Chemistrydepartment TianshuiNormalUniversityTianshui741018.China collegeofChemistryandChemicalEngineering LanzhouUniversityLanzhou730000.China

Pt(Ⅱ) and Pd(Ⅱ) complexes with 2′,3′,4′,5,7-pentahydroxy-flavone weresynthesized and characterized by elemental analysis, molar conductance, IR, ~1HNMR, TG-DTA, UV-Visspectroscopic techniques, and fluorescence analysis. The scavenging effect on the superoxide radical(O_2^-) and the inhibitory effect on lipid peroxides were also investigated. Both the ligand andthe complexes exhibit scavenging effect on superoxide radicals, and the effect of the complexes isgreater than that of the ligand. The Pt(Ⅱ) complex exhibits the strongest scavenging *** Pt(Ⅱ) and Pd(Ⅱ) complexes have the inhibitory effect on lipid peroxides, and the effect ofthe complexes is greater than that of the ligand, but the Pt(Ⅱ) complex has a high effect ofpromoting lipid peroxides.

关键词： inorganic chemistry metal complex 2′,3′,4′,5,7-pentahydroxy-flavone scavenging effect on superoxide radicals inhibitory effect on lipid peroxides

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From the Green's Function in Tight-Binding Representation to Interatomic Many-body Potentials

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Journal of Materials Science & Technology 1999年第4期15卷 315-319页

作者： Shaojun LIU(department of physics, Beijing normal University, Beijing 100875, china)Xiaobo WEI(department of physics, Liuzhou college of Education, Liuzhou 545005, china)Zhaodou CHEN Jun CAI and Benkun MA(department of physics, Beijing normal University, department of physics Beijing Normal University Beijing 100875 China department of physics Liuzhou College of Education Liuzhou 545005 China

In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method.

关键词： Rev Li Chen From the Green’s Function in Tight-Binding Representation to Interatomic Many-body Potentials body

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Codimension 3 nonresonant bifurcations of homoclinic orbits with two inclination flips

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Science china Mathematics 2005年第2期48卷 248-260页

作者： SHUI Shuliang & ZHU Deming college of Mathematics and physics, Zhejiang normal University, Jinhua 321004, china department of Mathematics, East china normal University, Shanghai 200062, china college of Mathematics and physics Zhejiang Normal University Jinhua China department of Mathematics East China Normal University Shanghai China

Homoclinic bifurcations in four-dimensional vector fields are investigated by setting up a local coordinate near a homoclinic orbit. This homoclinic orbit is principal but its stable and unstable foliations take inclination flip. The existence, nonexistence, and uniqueness of the 1-homoclinic orbit and 1-periodic orbit are studied. The existence of the two-fold 1-periodic orbit and three-fold 1 -periodic orbit are also obtained. It is indicated that the number of periodic orbits bifurcated from this kind of homoclinic orbits depends heavily on the strength of the inclination flip.

关键词： bifurcation, homoclinic orbit, non-resonance, inclination flip, 1-periodic orbit.

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Non-universal Gauge Bosons Z'and the Process e~+e~- →f

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Communications in Theoretical physics 2004年第3期41卷 419-424页

作者： YUE Chong-Xing~1 WANG Shun-Zhi~2 1 department of physics,Liaoning normal University,Dalian 116029,china 2 college of physics and Information Engineering,Henan normal University,Xinxiang 453002,china department of physics Liaoning Normal University Dalian 116029 college of physics and Information Engineering Henan Normal University Xinxiang 453002

Introduetion Altl、ough the standard model(SM)that bases on thega、lge gro、ip SU:(2)xU(1)has been sueeessful in de-seribing the Physies of eleetroweak interaetions,the meeh-anisn,of the eleetroweak symmetry breaking(... 详细信息

关键词： non-universal gauge bosons cross section TC2 models

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Robustness and breakup of the spiral wave in a two-dimensional lattice network of neurons

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Science china(physics,Mechanics & Astronomy) 2010年第4期53卷 672-679页

作者： MA Jun 1,2, TANG Jun 2 , ZHANG AiHua 3 & JIA Ya 2 1 department of physics, Lanzhou University of Technology, Lanzhou 730050, china 2 department of physics, Central china normal University, Wuhan 430079, china 3 college of Electrical and Information Engineering, Lanzhou University of Technology, Lanzhou 730050, china department of physics Lanzhou University of Technology Lanzhou 730050 China

The robustness and breakup of spiral wave in a two-dimensional lattice networks of neurons are investigated. The effect of small- world type connection is often simplified with local regular connection and the long-range connection with certain probability. The network effect on the development of spiral wave can be better described by local regular connection and changeable long-range connection probability than fixed long-range connection probability because the long-range probability could be changeable in realistic biological system. The effect from the changeable probability for long-range connection is simplified by multiplicative noise. At first, a stable rotating spiral wave is developed by using appropriate initial values, parameters and no-flux boundary conditions, and then the effect of networks is investigated. Extensive numerical studies show that spiral wave keeps its alive and robust when the intensity of multiplicative noise is below a certain threshold, otherwise, the breakup of spiral wave occurs. A statistical factor of synchronization in two-dimensional array is defined to study the phase transition of spiral wave by checking the membrane potentials of all neurons corresponding to the critical parameters(the intensity of noise or forcing current)in the curve for factor of synchronization. The Hindmarsh-Rose model is investigated, the Hodgkin-Huxley neuron model in the presence of the channel noise is also studied to check the model independence of our conclusions. And it is found that breakup of spiral wave is easier to be induced by the multiplicative noise in presence of channel noise.

关键词： spiral wave factor of synchronization breakup multiplicative noise robustness

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Observations favor the crossing of phantom divide lines

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Science china(physics,Mechanics & Astronomy) 2010年第3期53卷 562-566页

作者： HUANG TieTie1,2,3, WU PuXun2,3 & YU HongWei2,3 1department of physics, Xiangnan college, Chenzhou 423000, china 2department of physics and Institute of physics, Hunan normal University, Changsha 410081, china 3Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, Hunan normal University, Changsha 410081, china Xiangnan college Department of Physics Chenzhou China Hunan normal University Department of Physics and Institute of Physics Changsha China (GRID:grid.411427.5) (ISNI:***) Hunan normal University Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Changsha China (GRID:grid.411427.5) (ISNI:***) Hunan normal University Department of Physics and Institute of Physics Changsha China (GRID:grid.411427.5) (ISNI:***) Hunan normal University Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education Changsha China (GRID:grid.411427.5) (ISNI:***)

Using three different parameterized dark energy models, we reconstruct the properties of dark energy from the latest 397 Sne Ia, CMB and BAO with the present matter density, Ωm0, given prior. We find that, when Ωm0 is not small, for example, Ωm0 = 0.28 or 0.32, an evolving dark energy with a crossing of phantom divide line is favored and this conclusion seems to be model independent. We also find that the evolving properties of dark energy become more and more evident with the increase of Ωm0 given prior.

关键词： cosmology auelerating expansion dark energy

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D-Dimensional Dirac Fermions BEC-BCS Crossover Thermodynamics

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Communications in Theoretical physics 2007年第7期48卷 99-106页

作者： CHEN Ji-Sheng Institute of Particle physics & physics department,Central china normal University,Wuhan 430079,china Institute of Particle physics Central China Normal University physics department Central China Normal University

An effective relativistic continuum massive Proca Lagrangian action is used to account for the Lorentzvector condensation effects on the equation of state of the strongly interacting fermions *** interior quantumfluctuation effects are incorporated as an external field approximation indirectly through a fictive generalized ThomsonProblem counterterm *** general analytical formulas for the d-dimensional thermodynamics are given nearthe unitary limit region,In the non-relativistic limit for d=3,the universal dimensionless coefficientε=4/9 andenergy gap △/ε_f=5/18 are reasonably consistent with the existing theoretical and experimental *** the unitarylimit for d=2 and T=0,the universal coefficient can even approach the extreme occasion ξ=0 corresponding to theinfinite effective fermion mass m~*=∞,which can be mapped to the strongly coupled two-dimensional electrons and isquite similar to the three-dimensional Bose-Einstein condensation of ideal boson ***,for d=1,the universalcoefficient ξ is negative,implying the non-existence of phase transition from superfluidity to normal *** solutionsmanifest the quantum Ising universal class characteristic of the strongly coupled unitary fermions gas.

关键词： unitary fermions thermodynamics BEC-BCS crossover statistical methods

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Bell States and Two-Qubit Logic Gate with Superconducting Charge Qubits Coupling to a Nanomechanical Resonator

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Communications in Theoretical physics 2007年第12期48卷 999-1002页

作者： LIAO Jie-Qiao~1 and WANG Xin-Wen~(2,3)~1 department of physics,Hunan normal University,Changsha 410081,china~2 department of physics,Beijing normal University,Beijing 100875,china~3 department of Electronic Engineering and physics,Hunan University of Science and Engineering,Yongzhou 425100,china department of physics Hunan Normal University department of physics Beijing Normal University department of Electronic Engineering and physics Hunan University of Science and Engineering

We propose a scheme for generating Bell states involving two SQUID-based charge qubits by coupling themto a nanomechanical *** also show that it is possible to implement a two-qubit logic gate between the twocharge qu... 详细信息

关键词： Bell states superconducting charge qubit two-qubit logic gate nanomechanical resonator

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Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science china(physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2, SUN Weiguo1, HOU Shilin3 & FENG Hao4 1. Institute of physics, college of Chemical Engineering, Sichuan University, Chengdu 610065, china 2. Institute of Theoretical physics, Xihua normal University, Nanchong 637002, china 3. department of physics, china Oceanography University, Qingdao 266003, china 4. college of physics, Sichuan University, Chengdu 610065, china Institute of physics College of Chemical Engineering Sichuan University Chengdu China Institute of Theoretical physics Xihua Normal University Nanchong China department of physics China Oceanography University Qingdao China college of physics Sichuan University Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

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