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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 73.050, China 2 department of Physics, Central China Normal university, Wuhan 43.079, China 3.College of Electrical and Information Engineering, lanzhou university of Technology, lanzhou 73.050, China department of Physics Lanzhou University of Technology Lanzhou China department of Physics Central China Normal University Wuhan China College of Electrical and Information Engineering Lanzhou University of Technology Lanzhou 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

Syntheses,characterization,crystal structure and magnetic properties of copper(Ⅱ) α,β-unsaturated carboxylate complexes with trimethyl phosphate

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Chinese Science Bulletin 2001年第12期46卷 987-991页

作者： WANG Yaoyu, LIU Ping, SHI Qian, GAO Yici & SHI Qizhen1. department of Chemistry, Northwest university, Xi’an 710069, China 2. department of Chemistry, Wenzhou Teachers College, Wenzhou 3.5003. China 3. department of Chemistry, lanzhou university, lanzhou 73.000, China department of Chemistry Northwest University Xi’an China department of Chemistry Wenzhou Teachers College Wenzhou China department of Chemistry Lanzhou University Lanzhou China

Two ternary complexes Cu2A4[OP(OCH3.3.2 (A represents CH2=CH-COO- and CH2=C(CH3.-COO-) have been synthesized, and elemental analyses, IR, ESR, electronic reflectance spectra and magnetic studies were carried out. The single crystal X-ray diffraction shows that Cu2[CH2=C(CH3.-COO]4[OP(OCH3.3.2 is triclinic, with space group P1, a = 1.05128(13., b = 1.7559(5), c = 1.94479(3. nm, α =91.263.14)°,(β = 102.559(6)°,γ= 106.3.9(13.°, Z = 4 and R = 0.0668. Two copper(Ⅱ) atoms are bridged by four (a-methacrylate groups, and each copper(Ⅱ) atom is coordinated with a trimethyl phosphate molecule in the axial position, forming a distorted square pyramidal configuration. The symmetric center is between the two copper(Ⅱ) atoms, and the Cu-Cu bond distance is 0.26098(6) nm. The Cu-Cu distance and magnetic studies suggest that there exist anti-ferromagnetic interactions between the two copper(Ⅱ) atoms.

关键词： copper(Ⅱ ) complex α β-unsaturated carboxylate trimethyl phosphate magnetic property crystal structure.

A NONLINEAR GALERKIN METHOD WITH VARIABLEMODES FOR KURAMOTO-SIVASHINSKY EQUATION

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Journal of Computational Mathematics 1999年第3期17卷 243-256页

作者： Yu-jiang wu(Depadrtment of Mathematics, Shanghai university, Jiadiap Shanghai 201800, China department of Mathematics, lanzhou university, {3. 750000, China) 上海大学数学系上海

This article proposes a kind of nonlinear Galerkin methods with variable modes for the long-term integration of Kuramoto-Sivashinsky equation. It consists of finding an appropriate or best number of modes in the correction of the method. Convergence results and error estimates are derived for this method. Numerical examples show also the efficiency and advantage of our method over the usual nonlinear Galerkin method and the classical Galerkin method.

关键词： Kuramoto-Sivaskinsky equation nonlinear Galerkin method approximation convergence

Seasonal changes of endogenous ABA and cytokinins in environmental adaptation of different ecotypes of reed plants

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Journal of Environmental Sciences 1995年第4期7卷 449-454页

作者： Wang Hongliang , Zhang Chenglie(department of Biology, lanzhou university , lanzhou 73.000 , China)

ＳｅａｓｏｎａｌｃｈａｎｇｅｓｏｆｅｎｄｏｇｅｎｏｕｓＡＢＡａｎｄｃｙｔｏｋｉｎｉｎｓｉｎｅｎｖｉｒｏｎｍｅｎｔａｌａｄａｐｔａｔｉｏｎｏｆｄｉｆｆｅｒｅｎｔｅｃｏｔｙｐｅｓｏｆｒｅｅｄｐｌａｎｔｓＷａｎｇＨｏｎｇｌ... 详细信息

ＳｅａｓｏｎａｌｃｈａｎｇｅｓｏｆｅｎｄｏｇｅｎｏｕｓＡＢＡａｎｄｃｙｔｏｋｉｎｉｎｓｉｎｅｎｖｉｒｏｎｍｅｎｔａｌａｄａｐｔａｔｉｏｎｏｆｄｉｆｆｅｒｅｎｔｅｃｏｔｙｐｅｓｏｆｒｅｅｄｐｌａｎｔｓＷａｎｇＨｏｎｇｌｉａｎｇ，ＺｈａｎｇＣｈｅｎｇｌｉ...

关键词： ABA cytokinin ecotype environmental adaptation Phragmites communis T.

STABILITIES OF (A,B,C) AND NPDIRK METHODS FOR SYSTEMS OF NEUTRAL DELAY-DIFFERENTIAL EQUATIONS WITH MULTIPLE DELAYS

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Journal of Computational Mathematics 2003年第3期21卷 375-382页

作者： Guo-feng Zhang (department of Mathematics, lanzhou university, lanzhou 73.000, China) department of Mathematics Lanzhou University Lanzhou 730000

Consider the following neutral delay-differential equations with multiple delays (NMDDE)where γ> 0, L, Mj and Nj are constant complex- value d×d matrices. A sufficient condition for the asymptotic stability of NMDDE system (0.1) is given. The stability of Butcher's (A,B,C)-method for systems of NMDDE are studied. In addition, we present a parallel diagonally-implicit iteration RK (PDIRK) methods(NPDIRK) for systems of NMDDE, which is easier to be implemented than fully implicit RK methods. We also investigate the stability of a special class of NPDIRK methods by analyzing their stability behaviors of the solutions of (0.1).

关键词： Neutral delay differential equations (A,B,C)-method RK method Parallel diagonally-implicit iteration RK method.

Effects of additives on the aggregation of surfactants: binding domination

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Chinese Journal of Chemistry 1992年第3期10卷 237-244页

作者： LEI, Xue-Gong department of Chemistry, lanzhou university, lanzhou 73.000 department of Chemistry Lanzhou University Lanzhou 730000

The effects of electrolytes, alcohols, and urea on the aggregation of SDS, CTAB, and Triton X-100 at 25℃ have been investigated by fluorescence probing of pyrene. Both electrolytes and alcohols reduce the critical micelle concentration (CMC) of the ionic surfactants, while the effect of the former is more pronounced. It is shown that the effects of electrolytes mainly depend on the concentrations and especially the valence of the opposite charge ions, and only slightly depend on the same charge ions in respect of ion aggregate of micelle. The logarithm of CMC is not linearly correlated with the concentrations of the counter ion or the electrolytes. The results are rationalized in terms of Hartley's model. Propanol increases the CMC of TX-100, while electrolytes and urea do not. In all the three kinds of surfactant micelles the excitation spectrum of pyrene slightly red-shifts (ca. 4 nm) from that in water, but is not affected by the additives. The micropolarity of the environment in which pyrene molecule resides in SDS micelle decreases with the increase of the concentrations of electrolytes. This is not the case when alcohols and urea were added to SDS or to TX-100. It is suggested that the addition of electrolytes would result in more orderly orientation of SDS molecules. It is the binding strength of the counter ions that dominates the effects of additives on the aggregation of surfactants.

关键词： CMC binding domination Effects of additives on the aggregation of surfactants

Synthesis and Characterization of New Schiff Base and Polyoxa-azaCryptands and Their Rare Earth Cryptates with [1+1] Condensation and Reduction Methods

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Chinese Chemical Letters 1999年第12期10卷 995-998页

作者： Zhen MA Ru Dong YANG Lan YAN(department of Chemistry, lanzhou university, lanzhou, Gansu {3.) department of Chemistry Lanzhou University Lanzhou Gansu 730000 China

The Schiff base cryptand and its cryptates were synthesized with the methods of [1+1] condensation of trialdehyde and tris(2-aminoethyl)amine and obtained in 60-65%, 5-25% and 70-80% yields respectively with or without some rare earth elements as templates. The polyoxa-aza cryptand was produced in 72% and 60-70% yields with reduction of Schiff base and its cryptates respectively.

关键词： Schiff base polyoxa-aza cryptand rare earth condensation

VARIATIONAL PRINCIPLES OF PERFORATED THIN PLATES AND FINITE ELEMENT METHOD FOR BUCKLING AND POST-BUCKLING ANALYSIS

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Acta Mechanica Sinica 1991年第2期7卷 147-156页

作者： Yang Xiao Cheng Changjun (department of Mechanics,lanzhou university,lanzhou,73.000) department of Mechanics Lanzhou University Lanzhou

On the basis of the general theory of perforated thin plates under large deflections, variational principles with deflection w and stress function F as variables are stated in *** on these princi- ples,finite element method is established for analysing the buckling and post-buckling of perforated thin plates. It is found that the property of element is very complicated,owing to the multiple connexity of the region.

关键词： variational principle finite element method perforated thin plate buckling and post-buckling analysis

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 Physics, Chinese Academy of Sciences, lanzhou 73.000, China 2. department of Physics, Xianyang Normal university, Xianyang 712000, China 3. department of Modern Physics, lanzhou university, lanzhou 73.000, China 4. department of Applied Physics, Xi’an Jiaotong university, Xi’an 710049, China Institute of Modern Physics Chinese Academy of Sciences Lanzhou China department of Physics Xianyang Normal University Xianyang China department of Modern Physics Lanzhou University Lanzhou China department of Applied Physics Xi’an Jiaotong University Xi’an 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.