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On the Burgers-Ginzburg-Landau Equations

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Communications in Nonlinear Science and Numerical Simulation 1998年第3期3卷 143-147页

作者： Boling GUO and Haiyang HUANG(Center of Nonlinear Studies. Institute of Applied physics and ComputationalMathematics, beijing, 100088. china)(Dept. of Math. beijing normal university. beijing 100875. china)E-mail: hhywsg@*** Center of Nonlinear Studies Inst. Appl. Phys. and Compl. Math. Beijing 100088 China Dept. of Math. Beijing Normal University Beijing 100875 China

In this paper we consider the Burger-Ginzburg-Landau equations. and provethe existence of the global attractor in with finite Hausdorff and fractaldimensions.

关键词： Burger-Ginzbur-Landau equations mild solution global attractor hausdorff and fractal dimensions

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COSMIC PLASMA DYNAMO

空间科学学报 2002年第4期22卷 289-299页

作者： YANG Zhiliang(Astronomy department, beijing normal university, beijing 100875. Astronomydepartment BeijingNormalUniversity 北京 100875

A new dynamo model based on the polarization of plasma is presented in this *** the Maxwell equations in a moving medium, a magnetization vector can be causedwith Rongon current. The steady solar magnetic field is solved from the equations. Onthe assumption that the meridianal flow is ignored, the distribution of magnetic field isput out. In the model, there is no additional parameter considered. The intensity ofmagnetic field inside the sun ranges from 1-6T. The surface magnetic field around thepole is in the order of 1×10-3T, at low latitude the calculated surface magnetic fieldhas the order of 1×10-2 T. The maximum magnetic field is around 30° in latitude.

关键词：太阳风发动机模型等离子体磁场强度

Structural and mechanical properties of amorphous carbon films deposited by the dual plasma technique

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Journal of university of Science and Technology beijing 2008年第5期15卷 622-626页

作者： Yaohui Wang,Xu Zhang,Xianying Wu,Huixing Zhang,and Xiaoji Zhang Key Laboratory of the Ministry of Education of china for Beam Technology and Material Modification,Institution of Low Energy Nuclear physics,beijing normal university beijing Radiation Center,beijing 100875.china [a]Key Laboratory of the Ministry of Education of china for Beam Technology Material Modification Institution of Low Energy Nuclear Physics Beijing Normal University beijing Radiation Center Beijing 100875 China

Direct current metal filtered cathodic vacuum arc （FCVA） and acetylene gas （C2H2） were wielded to synthesize Ti-containing amorphous carbon films on Si （100）. The influence of substrate bias voltage and acetylene gas on the microstructure and mechanical properties of the films were investigated. The results show that the phase of TiC in the （111） preferential crystallographic orientation exists in the film,and the main existing pattern of carbon is sp2. With increasing the acetylene flow rate,the contents of Ti and TiC phase of the film gradually reduce; however,the thickness of the film increases. When the substrate bias voltage reaches -600 V,the internal stress of the film reaches 1.6 GPa. The micro-hardness and elastic modulus of the film can reach 33.9 and 237.6 GPa,respectively,and the friction coefficient of the film is 0.25.

关键词： metal containing amorphous carbon amorphous carbon films filtered arc acetylene flow rate bias voltage structure and properties

The kink-soliton and antikink-soliton in quasi-one-dimensional nonlinear monoatomic lattice

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Science china(physics,Mechanics & Astronomy) 2005年第2期48卷 150-157页

作者： XU Quan1 & TIAN Qiang2 1. Scientific and Technological Office, Daqing Teacher College, Daqing 163712, china 2. department of physics , beijing normal university, beijing 100875. china Scientific and Technological Office Daqing Teacher College Daqing 163712 China department of physics Beijing Normal University Beijing 100875 China

The quasi-one-dimensional nonlinear monoatomic lattice is analyzed. The kink-soliton and antikink-soliton are presented. When the interaction of the lattice is strong in the x-direction and weak in the y-direction, the two-dimensional (2D) lattice changes to a quasi-one-dimensional lattice. Taking nearest-neighbor interaction into account, the vibration equation can be transformed into the KPI, KPII and MKP equation. Considering the cubic nonlinear potential of the vibration in the lattice, the kink-soliton solution is presented. Considering the quartic nonlinear potential and the cubic interaction potential, the kink-soliton and antikink-soliton solutions are presented.

关键词： two-dimensional nonlinear lattice, quasi-one-dimensional nonlinear lattice, kink-soliton, antikink-soliton.

Development and application of ergodicity model with FRCM and FLAR for hydrological process

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Science china(Technological Sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2, LIN Xin3 & ZENG WenYi4 1 College of Water Science, Key Laboratory for Water and Sediment Sciences of the Ministry of Education, beijing normal university, beijing 100875. china 2 School of Science, beijing Institute of Education, beijing 100011, china 3 School of Mathematical Sciences, beijing normal university, beijing 100875. china 4 College of Information Science and Technology, beijing normal university, beijing 100875. china 1. College of Water Science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing 100875 China 2. School of Science Beijing Institute of Education Beijing 100011 China 3. School of Mathematical Sciences Beijing Normal University Beijing 100875 China 4. College of Information Science and Technology Beijing Normal University Beijing 100875 China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2004) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression

Effects of chlorogenic acid, an active compound activating calcineurin, purified from Flos Lonicerae on macrophage

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Acta Pharmacologica Sinica 2004年第12期25卷 119-123页

作者： He-zhen WU, Jing LUO, Yan-xia YIN, Qun WEI2 department of Biochemistry and Molecular Biology, beijing normal university, beijing 100875. china department of Biochemistry and Molecular Biology Beijing Normal University

AIM: To investigate the activation of chlorogenic acid (CHA) purified from Flos Lonicerae to calcineurin and its effects on macrophage functions in vivo and in vitro. METHODS: According to the screening results that Flos Lonicerae could activate calcineurin, the active component which could activate calcineurin was purified from Flos Lonicerae by column chromatography on silica gel and identified as CHA. The activation of CHA on calcineurin had been validated with both p-NPP and P-labeled RII peptide as the substrates. The clearance of charcoal particles in 32 normal mice and the cytotoxicity of U937 to MCF-7 were used together to determine the effects of CHA on macrophage functions. RESULTS: CHA could activate calcineurin, and the concentration of CHA on maximal activating calcineurin was 282.5 μmol/L. CHA administration (10 mg/kg, ig×7 d) significantly enhanced the mac- rophage functions in normal mice. CHA (70.6, 141.2, and 282.5 μmol/L) obviously increased the cytotoxicity of U937 to MCF-7. CONCLUSION: CHA could activate calcineurin and enhance the macrophage functions in vivo and in vitro, and its functions in vivo may be realized via the signal pathways of calcineurin.

关键词： calcineurin macrophage chlorogenic acid Flos Lonicerae

Ergodicity of Reversible Reaction Diffusion Processes with General Reaction Rates

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Acta Mathematica Sinica,English Series 1994年第1期10卷 99-112页

作者： Chen Mufa Ding Wanding Zhu Dongjin department of Mathematics beijing normal university beijing,100875.china department of Mathematics Animi normal university Wuhu,241000 china 1. department of Mathematics Beijing Normal University 100875 Beijing China 2. department of Mathematics Anhui Normal University 241000 Wuhu China

In this paper,a class of reaction diffusion processes with general reaction rates is studied.A necessary and sufficient condition for the reversibility of this calss of reaction diffusion processes is given,and then t... 详细信息

关键词： Ergodicity of Reversible Reaction Diffusion Processes with General Reaction Rates

ASYMPTOTIC normalITY OF M-ESTIMATES IN THE EV MODEL

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Systems Science and Mathematical Sciences 1997年第3期10卷 225-236页

作者： CUI Hengjian(department of Mathematics, beijing normal university, beijing 100875. china) 北京师范大学数学系北京

The M-estimate of parameters in the errors-in-variables (EV) model Y =xτβ0+∈,X =x+u ((∈,uτ)τ is a (p+1)-dimensional spherical error, Coy[(∈, uτ)τ] =σ2Ip+1)being considered. The M-estimate βn,, of β0 under a general ρ(·) function and the estimateof σ2 are given, the strong consistency and asymptotic normality of βn as well as are obtained. The conditions for the ρ(·) function in this paper are similar to that of linearexpression of M-estimates in the linear regression model.

关键词： EV model M-estimate strong consistency asymptotic normality

Theoretical Study on the Pyrolysis Mechanism and Kinetics of 3-Hydroxy-3-Methyl-2-Butanone

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Chinese Chemical Letters 1998年第11期9卷 0-0页

作者： Wen Lin FENG Jie Hao CHEN Yan WANG (department of chemistry, beijing normal university, beijing 100875. beijing normal Univ Dept Chem Beijing 100875 Peoples R China

The mechanism and kinetics for the decomposition of 3-hydroxy-3-methyl-2-butanone have been studied by using the ab initio RHF/3-21G method. The calculated activation barrier of the reaction is 249.6kJ/mol which is in reasonable agreement with the experimental data (222.2±3kJ/mol). The calculated results show that the decomposition is a concerted process with hydrogen transferring and bond breaking via a five-membered cyclic transition state. The thermal rate constants of the decomposition are obtained by calculating microcanonical probability fluxes through transition state1.

关键词： Kinetics mechanism theoretical study rate constants