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Structure and Magnetic Properties of Ni-doped ZnO Powder

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Journal of wuhan university of {2.(Materials science) 2010年第5期25卷 770-773页

作者：高放赵俊 department of Electronic science and {2. Huazhong University of Science and Technology

Ni-doped ZnO nanopowder （Zn0.98Ni0.2.） was synthesized by improved coprecipitation method. The average particle size of the powder was estimated to be 50 nm. The powder was then processed by thermal treatment. Samples were annealed at 1 073, 1 2.3, and 1 473 K, respectively. The solubility of NiO in ZnO and the lattice parameters of ZnO both increased with the temperature. The magnetic property of the doped samples was examined, and hysteresis loops were got. The results showed all the samples were ferromagnetic, while powder processed at 1 2.3 K for 4 h got a highest saturation magnetization （Ms） of 0.0457 emu/g. Also, magnetic properties were related to the grain size of the powder.

关键词： ferromagnetism diluted magnetic semiconductor Ni-doped ZnO coprecipitation solid state reaction

A delay differential equation solver based on the parallel Adams algorithms

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Communications in Nonlinear science and Numerical Simulation 2001年第1期6卷 28-34页

作者： Chengjian ZHANG and Hongbing YU(department of Mathematics, huazhong university of science and technology, {2.,China) department of Mathematics Huazhong University of Science and Technology Wuhan 430074 China

This paper constructs a class of parallel Adams algorithms for the systems of delay differential equations. The results on convergence and stability are given. The theoretical analysis and numerical test shows that th... 详细信息

关键词： parallel algorithms Adams algorithms delay differential equations

AN IMPLICIT SCHEME FOR INCOMPRESSIBLE LBGK MODEL

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Journal of Hydrodynamics 2005年第3期17卷 330-337页

作者： DURui SHIBao-chang WANGGuang-chao LIUHong-juan departmentofMathematics HuazhongUniversityofScienceandTechnologyWuhan430074China departmentofMathematics HuazhongUniversityofScienceandStateKeyLaboratoryofCoalCombustionHuazhongUniversity430074China／／TechnologyWuhan430074ChinaofScienceandTechnologyWuhan

In this paper, an implicit scheme (also called the θ method) was proposed for the Lattice Bhatager-Gross-Krook (LBGK) model simulating incompressible flows. The new parameter θ made the model more flexible. Through the Chapman-Enskog procedure the impressible Navie-Stokes equations could be recovered with the coupled kinetic viscosity. Boundary conditions were treated briefly and it kept the numerical accuracy of the Lattice Boltzmann Method (LBM). The two-dimensional Poiseuille flow was simulated with different values of the parameters. It is found that the numerical accuracy and stability of the implicit scheme can be improved if some adaptable parameters are chosen.

关键词： Lattice Boltzmann Method (LBM) implicit scheme θ-Lattice Bhatager-Gross-Krook (LBGK) model Poiseuille flow

DYNAMIC SIMULATION OF ROTATING SHELLS COUPLED WITH LIQUID

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Acta Mechanica Solida Sinica 2001年第2期14卷 169-175页

作者： Wei Fayuan Li Shiqi Huang Yuying~1 Zhong Yifang (College of Mechanical science and Engineering, huazhong university of science and technology, {2., China) (1 department of mechanics, huazhong university of science and technology, {2.,China) ***

The dynamic behaviors of rotating shells coupled with liquid areshown. The shell under con- sideration has arbitrary boundaryconditions and a complex shape. A modified boundary element methodand finite strip technique are used to improve the computingefficiency and to guarantee the continuity conditions on theliquid-shell interaction plane. The effects of various parameterssuch as shell's thickness and liquid depth are investigated. Dynamicsimulations are applied to several typical shell-liquid systems, andthe natu- ral frequencies, mode shapes and response of vibration arecalculated numerically.

关键词： rotting shells dynamic simulation fluid-solid interaction

Exact eigenstates for a class of models describing multiphoton processes in the presence of seven bosonic modes

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science China(Physics,mechanics & Astronomy) 2004年第6期47卷 649-657页

作者： ZHAN Zhiming1,LI Weibin2.YOU Jun2.XIE Xiaotao2.& YANG Wenxing2.1.State Key Laboratory of Laser technology,huazhong university of science and technology,{2.,China 2.department of Physics,huazhong university of science and technology,{2.,China 1. State Key Laboratory of Laser technology Huazhong University of Science and Technology 430074 Wuhan China 2. department of Physics Huazhong University of Science and Technology 430074 Wuhan China

We present the analytical expressions of eigenstates and eigenenergies by using a parameter λ without the assumption of Bethe anzatz for three kinds of seven-bosonic-mode mixing models. The parameter is shown to be determined by the roots of a simple polynomial. We also demonstrate the exact analytical expressions of eigenstates and energies without any unknown parameter.

关键词： spectra, eigenstate, eigenvalue.

A Cognitive science Framework for the Analysis of Knowledge-Based Systems

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Journal of Systems Engineering and Electronics 1994年第2期5卷 60-67页

作者： Feng Shan (department of Automatic Control Engineering, huazhong university of science and technology, {2.,Hubei, 43.074 PRC) department of Automatic Control Engineering Huazhong University of Science and Technology Wuhan Hubei 430074 PRC

The paper presents a cognitive science framework for the analysis of knowledge-based systems,including people, media. simulation and expert systems, resulting in a practical model for the procedures ofknowledge engineering. Starting with the construct of a social organization model driven by anticipationand thed differentiating this into pesonal scientists with diverse relations to people and their internal andexternal communication, it provides powerful and general model of society. people, and the roles of peoplein society. This model extends naturally ic the role of conventional media in the knowledge processes ofsociety and the new roles of computer-based simulation and expert systems. In particular it provides amodel of knowledge transfer that enables the processes of knowledge engineering to be analyzed andautomated.

关键词： Cognitive modeling Knowledge-based systems Knowledge engineering Communal scientist Media.

NMDA and AMPA receptors mediate intracellular calcium increase in rat cortical astrocytes

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Acta Pharmacologica Sinica 2004年第6期25卷 12-18页

作者： Bo HU, Sheng-gang SUN2. E-tang TONGNeurology department, Union Hospital, Tongji College, huazhong university of science and technology, {2. 43002., China Neurology department Union Hospital Tongji College Huazhong University of Science and Technology Wuhan 430022 China

AIM: To study the effect of glutamate on the intracellular calcium signal of pure cultured rat astrocytes and the roleof N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA) re-ceptors in the procedure. METHODS: The fluorescence of calcium was measured by Fura-2.AM (F345/F380).RESULTS: L-Glutamate induced [Ca2.]i increase in most of the cells in concentration- and time-dependent *** 50 mmol/L induced the fluorescence increase by almost three to four times, while the effect of AMPA 50mmol/L was just half of that of D-(-)-2.amino-5-phosphonopentanoic acid (D-AP-5; a selective antagonist of theNMDA receptor). 6-Cyano-7-nitroquinoxaline-2.3-dione (CNQX, a selective antagonist of the AMPA receptor)abolished the effects of NMDA and AMPA, respectively. D-AP-5 and CNQX simultaneously or respectively attenu-ated the effect of L-glutamate at different degrees, but could not abolish it entirely. CONCLUSION: Glutamatemodulated intracellular Ca2. of pure cultured rat astrocytes through different pathways. The activation of NMDAand AMPA receptors took part in the complex mechanisms.

关键词： glutamate astrocytes NMDA receptors AMPA receptors calcium

A New Multisoliton Solution to (2.1)-Dimensional KdV Equation

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Communications in Theoretical Physics 2004年第5期41卷 669-670页

作者： PENG Yan-Ze~(1,2. 1 department of Mathematics,huazhong university of science and technology,{2.,China2.department of Mathematics and Physics,Henan university of science and technology,Luoyang 471003,China department of Mathematics and Physics Henan University of Science and Technology Luoyang 471003 China

A new multisoliton solution to the(2.1)-dimensional KdV equation is obtained by means of the truncatedPainleve expansion method and a direct ansatz *** new exact solution is periodic in the propagating directionx and exponentially decaying in y and thus it is called periodic solitons.A typical spatial structure of it is illustrated bythe figures.

关键词： (2.1)-dimensional KdV equation periodic solitons truncated Painleve expansion method

Numerical simulations and experimental investigations on transverse effects of two-wave mixing in a photovoltaic photorefractive crystal

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science China(Physics,mechanics & Astronomy) 2010年第5期53卷 856-863页

作者： CAI Xin1,2.LIU JinSong1 & WANG ShengLie1 1 wuhan National Laboratory for Optoelectronics,School of Optoelectronic science and Engineering,{2.,wuhan 43.074,China 2.School of science,wuhan university of technology,wuhan 430070,China 1. wuhan National Laboratory for Optoelectronics School of Optoelectronic Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China2. School of Science Wuhan University of Technology Wuhan 430070 China

The transverse effects of two Gauss waves mixing in a photovoltaic photorefractive crystal,i.e.,the dynamical evolutions of signal beam with different parameters,are traced numerically and *** the one-dimensional numerical simulations and two-dimensional experimental investigations show that the self-focusing effect of signal beam becomes more obvious as the intensity of pump beam and the angle between the signal and pump beams *** accordance with these results,the state of two Gaussian waves mixing is controllable.

关键词： numerical simulation experimental investigation two-wave mixing transverse effects Gaussian distribution