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Science bulletin 2011年第34期56卷 3654-3660页

作者： bI Qiao & LIU Jie department of Physics, School of Science, wuhan University of Technology, wuhan 430070, China department of Physics School of Science Wuhan University of Technology

Since Gibbs synthesized a general equilibrium statistical ensemble theory, generalizing the Gibbsian theory to non-equilibrium phenomena has been a dream for some theorists. However, the status of the theory for the n... 详细信息

bstract>Since Gibbs synthesized a general equilibrium statistical ensemble theory, generalizing the Gibbsian theory to non-equilibrium phenomena has been a dream for some theorists. However, the status of the theory for the non-equilibrium ensemble formalism is not as well established as the Gibbsian ensemble theory. In this work, we explore the formalism behind the non-equilibrium statistical ensemble theory based on the sub-dynamic kinetic equation originating from the brussels-Austin school and developed further by others. The key is establishing a similarity transformation between Gibbsian ensembles and the sub-dynamic ensemble. Using this way, we study a spin-boson model with strong coupling. A reduced density operator for the canonical ensemble can be easily obtained and the relevant decoherence-free property is revealed.

关键词： subdynamics statistical ensemble non-equilibrium statistical physics

ADMISSIbLE　ESTIMATES　IN　THE　IMPORTANT　CLASS　OF　ESTIMATES　OF　THE　COVARIANCE　MATRIX

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Chinese Annals of Mathematics,Series b 1994年第4期15卷 435-442页

作者： XIE MINYU(department of Mathematics, Central China Normal Universityt wuhan 430070, China.) 华中师范大学数学系湖北武汉 430070

Let X1,X2(where N>m)be independent Nm(μ,∑) random vectors, and putwhere T is upper- triangular with positive diagonal elements. The author considers the problemof estimating ∑,and restricts his attention to the class of estimates is any diagonal matrix and b* is any nonnegative constant} because it has the following attractive features:(a) Its elements are all quadratic forms of the sufficient and complete statistics (X, T).(b) It contains all estimates of the form(and), which constructa complete subclass of the class of nonnegative quadratic estimates (where X = (X1,…, XN)') for any strict convex loss function.(c)It contains all invariant estimates under the transformation group of *** author obtains the Characteristics for an estimate of the formof ∑ to be admissible in when the loss function is chosed as tr(∑-1∑-Ⅰ)2, and shows,by an example, that(and)is admissible in can not imply itsadmissibility in .

关键词： Covariance matrix Admissible estimate bartlett's decomposition.

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 China 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

ELECTRO-THERMAL EFFECTS AND DEFORMATION RESPONSE OF CARbON FIbER MAT CEMENT bEAMS

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Acta Mechanica Solida Sinica 2003年第4期16卷 359-365页

作者： Zhu Sirong Li Zhuoqiu Song Xianhui (department of Engineering Structures and Mechanics,wuhan University of Technology,wuhan 430070,China) department of Engineering Structures Wuhan University of Technology Wuhan 430070 China

A carbon fiber mat is a sheet composed of intercrossing short carbon fibers,which has more stable and lower electrical resistivity compared with dispersed short carbon fiber mixed in *** carbon fiber mat cement could exhibit obvious electro-thermal *** electrified,the temperature of composite structures made up of cement mortar and carbon fiber mat will rise *** the temperature field is not uniform,temperature difference will cause structures to deform,which can be used to adjust the deformation of *** temperature field and deformation response driven by the electro-thermal effects of a type of carbon fiber mat cement beams are ***,the temperature and deformation responses are studied using theories of thermal conduction and ***,experimental results are given to verify the theoretical *** two parts lay the foundation for temperature and deformation adjustment.

关键词： carbon fiber mat cement electro-thermal effect deformation response

Synthesis and Characterization of 2-cetyl-3-20 keto acid(N-ethyl perfluorinated octyl sulfonamide) N-ethyl ester

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Journal of wuhan University of Technology(Materials Science) 2009年第2期24卷 292-294页

作者：翁睿 department of Composites Wuhan University of Technology

2-Cetyl-3-20 keto acid（N-ethyl perfluorinated octyl sulfonamide） N-ethyl ester was synthesized by the reaction of N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide and alky ketene dimer. The experimental results show that the yield of products can be 89% when the molar ratio of perfluorinated octyl sulfonamide to ketene dimer is 1 ： 1.1 and the reaction lasts about four hours at 80 ℃. The structure of the product was characterized by FTIR and ^1HNMR. The product can dissolve in polar solvents such as NMP, DMAC, THF, DMSO, CHCl3, and 10% weight-loss temperature measured by TGA is 202℃.

关键词： keto ester N-ethyl-N-hydroxyethyl perfluorinated octyl sulfonamide thermal performance

Dimensions of modified besicovitch-Eggleston sets

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Science China Mathematics 2006年第2期49卷 245-254页

作者： XIE Yuqiong & WEN Zhixiong department of Mathematics, wuhan University of Technology, wuhan 430070, China School of Mathematics and Statistics, wuhan University, wuhan 430072, China department of Mathematics Wuhan University of Technology Wuhan China School of Mathematics and Statistics Wuhan University Wuhan China

We consider the variants of besicovitch-Eggleston sets in symbolic spaces, and determine their fractal dimensions.

关键词： besicovitch-Eggleston set fractal dimension symbolic space multifractal.

Electronic Structures and Chemical bonds of Cobaltite and Ni-Doped

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Journal of wuhan University of Technology(Materials Science) 2005年第3期20卷 48-51页

作者：闵新民 department of Applied Chemistry Wuhan University of Technology

The relation among electronic structure, chemical bond and thermoelectric property of Ca3 Co2 O6 and Ni-doped was studied by density function theory and discrete variation method（DFT-DVM）. The results indicate that the highest valence band（ HVb ）attd the lowest conduction band（ LCb ） are mainly attribuled to Co3d, Ni3d and O2p atomic orbitals. The property of a semiconductor is shown from the gap between HVb and LCb. The gap of Ni-doped one is less than that of Ca3 Co2 O6. The non-metal bond or ceramic characteristic of Ni-doped one is weaker than that of Ca3 Co2 O6, but the metal characteristics of Ni-doped one are stronger than those of Ca3 Co2 O6. The thermoelectric property should be improved by adding Ni element into the system of Ca3 Co2 O6 .

关键词： cobaltite Ni- doped electronic structure chemical bond thermoelectric property

On　Orthogonal　Latin　Squares　and　Geodetic　blocks

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Systems Science and Systems Engineering 1997年第3期7卷 21-29页

作者： LI Xiangwen department of Mathematics, Huazhong Normal University, wuhan 430070

In this paper, we use the concept of an allowable geodetic block which we propose here and orthogonal latin square to construct geodetic blocks which generalize the construction of Ho jin Lee .

关键词： geodetic block unique vertex shortest path

Electronic Structure and Thermoelectric Properties of Na and Ni-doped Ca_3Co_2O_6

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Journal of wuhan University of Technology(Materials Science) 2006年第3期21卷 94-96页

作者：闵新民 department of Applied Chemistry Wuhan University of Technology Wuhan 430070 ChinaState Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of Technology Wuhan 430070China

The electronic structures of Ca3Co2O6, Na and Ni doped models were studied by the quantum chemical software of Cambride Serial Total Energy Package （CASTEP） that is based on deusity function theory （DFT） and psendo-potential. The electronic conductivity, seebeck coefficient, thermal conduetivity and figure of merit （Z） were computed. The energy band structure reveals the form of the impurity levels due to the substitutional imapurity in semiconductors. Na-doped model stunts the character of p-type semiconductor, but Xi-doped model is n-type semiconductor. The calculation results show that the electric conduetirity of the doped model is higher than that of the non-doped model, while the Seebeck coefficient and thermal conductivity of the doped model are lower than those of the non-doped one. because of the great increase of the electric conductivity, Z of Na- doped model is enhanced and thermoelectric properties are improved. On the other hand, as the large decline of Seebeck coefficient, Z of Ni-doped model is less than that of the non-doped model.

关键词： cobalt oxide substitutional impurity quantum chemical calculation electronic structure thermoelectric property