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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 {2., Jinhua 32.004, china department of Mathematics, East china normal {2., Shanghai 2.0062. 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.

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,{2. 2. Institute of Theoretical physics, Xihua normal university, Nanchong 637002.{2. 3. department of physics,{2. Oceanography university, Qingdao 2.6003,{2. 4. College of physics, Sichuan university, Chengdu 610065,{2. 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.

The Research of Scattering Cross-Section and Energy-Extraction in FEL

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Chinese Journal of Lasers 1995年第1期B4卷 25-29页

作者： ZHU Jiaqing (department of physics,Central{2. normal university,Wuhan,430070,china) Central china normal Univ Wuhan China

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ＴｈｅＲｅｓｅａｒｃｈｏｆＳｃａｔｔｅｒｉｎｇＣｒｏｓｓ－ＳｅｃｔｉｏｎａｎｄＥｎｅｒｇｙ－ＥｘｔｒａｃｔｉｏｎｉｎＦＥＬＴｈｅＲｅｓｅａｒｃｈｏｆＳｃａｔｔｅｒｉｎｇＣｒｏｓｓ－ＳｅｃｔｉｏｎａｎｄＥｎｅｒｇｙ－ＥｘｔｒａｃｔｉｏｎｉｎＦＥＬ￥ＺＨ...

关键词： free-electron laser scattering cross-section

Analytic Solution of the Three-Variable Dynamical Equations of Oscillation Phenomena in B-Z Reaction

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Chemical Research in Chinese Universities 2001年第3期17卷 311-314页

作者： LU Ling (department of physics, Liaoning {2. university, Dalian 11602., P. R. china) department of physics Liaoning Normal University Dalian 116029 China

The dynamical behaviour of the inorganic bromate oscillator catalyzed by manganese ions in the B-Z reaction is discussed, a three-variable nonlinear dynamical equations of the oscillation phenomena have been obtained,... 详细信息

关键词： B-Z reaction Oscillation Analytic solution

Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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Science china(physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3 & BAO Jingdong1,2.1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing normal university, Beijing 100875,{2. 2. physics department, Beijing normal university, Beijing 100875,{2. 3.{2. Institute of Atomic Energy, Beijing 102.13,{2. Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China physics department Beijing Normal University Beijing China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.8Cm(2.Mg,4n)2.0Hs, 2.4Pu(30Si,4n)2.0Hs, 2.8U(36S,4n)2.0Hs and 2.6Ra(48Ca,4n)2.0Hs using a two-parameter Smoluchowski equation. It is found from our results that 2.6Ra(48Ca,4n)2.0Hs and 2.8U(36S,4n)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

Transitional function of DG to CA3 in the hippocampus

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Progress in Natural Science:Materials International 2007年第12期17卷 1436-1444页

作者： Yan Chuankui1 and Liu Shenquan2.1. department of Mathematics, Hangzhou normal {2., Hangzhou 310036, china 2. department of Applied Mathematics, School of Mathematical Sciences, South china {2. of Technology, Guangzhou 510640, china) department of Mathematics Hangzhou Normal University Hangzhou 310036 China department of Applied Mathematics School of Mathematical Sciences South China University of Technology Guangzhou 510640 China

Using single cell channel model, the transmission features of CA3-DG network in the hippocampus are investigated. The influence of the stimulation on discharge pattern of pyramidal neurons is analyzed, which shows that it starts with period spiking discharges, followed by period-doubling bifurcation to chaos, and period 3 discharge evolving into chaos, and ultimately a period of bursting discharges. By the synaptic model, the CA3-DG network model is constructed, which analyzes the summation of postsynaptic currents in the network, the influence of postsynaptic current on discharge rhythm as well as the mechanism of bursting discharges. The strong capacity of spatiotemporal encoding in the network indicates the features of CA3 network during the information transmission process in the hippocampus. The modeling result with time delay of the synaptic transmission is in accordance with the experimental phenomena of action potential in the hippocampus.

关键词： hippocampus CA3-DG period-doubling bifurcation chaos.

Theoretical study on thermal decomposition of azoisobutyronitrile in ground state

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Science china Chemistry 2004年第5期47卷 373-380页

作者： SUN Chengke1,2. ZHAO Hongmei1 & LI Zonghe1 1. department of Chemistry, Beijing normal {2., Beijing 100875, china 2. department of Chemistry, Qujing normal College, Qujing 655000, china Dept. of Chem. Beijing Normal Univ. Beijing 100875 China Dept. of Chem. Qujing Normal Coll. Qujing 655000 China

The thermal decomposition mechanisms of azoisobutyronitrile (AIBN) in the ground state have been investigated systematically. Based on the potential energy surfaces (PES) of various possible dissociation paths obtained using the semiempirical AM1 method with partial optimization, the density function theory B3LYP/6-311G* method was employed to optimize the geometric parameters of the reactants, the intermediates, the products and the transition states, which were further confirmed by the vibrational analysis. The obtained results show that the re- action process of the two-bond (three-body) simultaneous cleavage Me2.CN)C─ N=N─ C(CN)Me2. 2.e2.CN)C?+N2.is much more favorable than the reaction process of the two one- bond asynchronous cleavage Me2.CN)CN=N─C(CN)Me2.? Me2.CN)CN=N?+ Me2.CN)C?? Me2.CN)C?+ N2. It was suggested that the electron shrinking effect of double bond (─N=N─) in AIBN and the stabilities of the Me2.CN)C?radical as well as N2.molecule are main factors of leading to the reaction proceeding in the former pathway. The calculation results were consistent with all the experimental facts.

关键词： azoisobutyronitrile, radicals, thermal decomposition, density function theory (DFT).

K-uniformly rotund spaces and k-uniformly smooth spaces

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Chinese Science Bulletin 1998年第2期43卷 92-95页

作者： Suyalatu 1 and WU Congxin 2.1. department of Mathematics,Inner Mongolia normal {2., Huhhot 01002., china 2. department of Mathematics, Harbin Institute of Technology, Harbin 150006, china department of Mathematics Inner Mongolia Normal University Huhhot China department of Mathematics Harbin Institute of Technology Harbin China

The conception of k_uniform smoothness (KUS) is introduced. It is the extension of the conception of uniform smoothness. It is proved that the k_uniform smoothness and Sullivan’s K_uniform rotundity (KUR) are the daul notions. X+* is a KUR space if and only if X is a KUS space, X+* is a KUS space if and only if X is a KUR space. If X is a KUS space, then X is a (K+1)US space. It is also proved that the KUS space includes the Nan’s k_strongly smooth space.

关键词： K_uniform smoothness K_uniform convexity.

Effect of annealing treatment on the structural, optical, and electrical properties of Al-doped ZnO thin films

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Rare Metals 2007年第3期26卷 247-253页

作者： LI Li FANG Liang CHEN Ximing LIU Gaobin LIU Jun YANG Fengfan FU Guangzong KONG Chunyang College of Photoelectric Engineering Chongqing University of Posts and Telecommunications Chongqing 400065 China department of Applied physics Chongqing University Chongqing 400044 China department of physics Chongqing Normal University Chongqing 400047 China

Highly conductive and transparent Al-doped ZnO （AZO） thin films were prepared from a zinc target containing Al （1.5 wt.%） by direct current （DC） and radio frequency （RF） reactive magnetron sputtering. The structural, optical, and electrical properties of AZO films as-deposited and submitted to annealing treatment （at 300 and 400℃, respectively） were characterized using various techniques. The experimental results show that the properties of AZO thin films can be further improved by annealing treatment. The crystallinity of ZnO films improves after annealing treatment. The transmittances of the AZO thin films prepared by DC and RF reactive magnetron sputtering are up to 80% and 85% in the visible region, respectively. The electrical resistivity of AZO thin films prepared by DC reactive magnetron sputtering can be as low as 8.06 x 10-4 Ωcm after annealing treatment. It was also found that AZO thin films prepared by RF reactive magnetron sputtering have better structural and optical properties than that prepared by DC reactive magnetron sputtering.

关键词： AZO thin films structure optical and electrical properties annealing transmittance spectra electrical resistivity