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Chinese Journal of Chemistry 1997年第1期15卷 54-59页

作者： LI, Shu-Lan LIU, De-Xin YANG, Zhao-HeDepartment of Chemistry, shandong university, jinan, shandong 250100, china National Laboratory of Crystal Materials, shandong university, jinan, shandong 250100, china Department of Chemistry Shandong University Jinan Shandong 250100 China National Laboratory of Crystal Materials Shandong University Jinan Shandong 250100 China

Monoaqua salicylaldehyde-o-aminobenzoic acid Ni(Ⅱ) monohydrate (cp1) and monoaqua o-vanillin-o-aminobenzoic acid Ni(Ⅱ) monohydrate (cp2) were synthesized. The composition and structures of these two compounds were analyzed. Their thermal stability and non-isothermal kinetics were also investigated by use of TG and DTG curves. The possible reaction mechanisms in their first steps of thermal decomposition reactions were deduced by means of integral and differential methods. Thermodecomposition kinetic equations of the compounds are as follows:Cp1: da/At = A . exp(-E/RT) . 3/2(1 - a)4/3 . [1/(1 - a)1/3 -1]-1 Cp2 : da/At = A . exp(-E/RT) . (1 - a)

关键词： Schiff base compound amino acid nickel(Ⅱ) kinetics nonisothermal

Genetic diversity of the endangered species Rosa rugosa *** china and implications for conservation strategies

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Journal of Systematics and Evolution 2009年第6期47卷 515-524页

作者： ~1Ji-Hong YANG ~1Shu-Ping ZHANG ~2Jian LIU ~1Wen ZHAI ~(1,2)Ren-Qing WANG~* 1(school of Life Sciences,shandong university,jinan 250100,china) 2(Institute of Environment Research,shandong university,jinan 250100,china) (school of Life Sciences Shandong University Jinan 250100 China) (Institute of Environment Research Shandong University Jinan 250100 China)

Rosa rugosa *** one of the dominant and important shrub species in estuary dunes and shingle beaches of northern ***,its area of distribution,the number of populations,and the size of each population have decreased rapidly in the past two decades because of habitat degradation and *** amplified polymorphic DNA markers were used to determine the genetic diversity of four remaining large natural populations of *** and to discuss an effective conservation strategy for this endangered species in *** genetic variations were detected in *** populations in *** mean percentage of polymorphic loci(P%) within four local populations was 57.99%,with the P%of the total population being 75.30%.Mean Shannon’s information index(H0) was 0.2826,whereas total H0was *** genetic differentiation among populations was 0.1878, which indicates that most genetic diversity occurs within *** Tumenjiang(TMJ) showed the highest genetic diversity(P%= 66.27%;H0= 0.3117) and contained two exclusive *** Changshandao (CSD) showed higher genetic diversity(P%= 59.04%;H0= 0.3065).Populations TMJ and CSD contained 95.33% and 99.33%,respectively,of loci with moderate to high frequency(P>0.05) of the total *** results indicate that populations TMJ and CSD should be given priority for in situ conservation and regarded as seed or propagule sources for ex situ *** results of the present study also suggest that *** in china has become endangered as a result of human actions rather than genetic depression of populations;thus,human interference should be absolutely forbidden in *** habitats.

关键词： china genetic diversity in situ conservation random amplified polymorphic DNA(RAPD) Rosa rugosa

DFT study of the conductance of molecular wire:The effect of coupling geometry and intermolecular interaction on the transport properties

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Science china Chemistry 2006年第6期49卷 492-498页

作者： QI Yuanhua1,2, GUAN Daren1 & LIU Chengbu1 1. Institute of Theoretical Chemistry, shandong university, jinan 250100, china 2. school of Physics and Microelectronics, shandong university, jinan 250061, china Institute of Theoretical Chemistry Shandong University Jinan China school of Physics and Microelectronics Shandong University Jinan China

The density functional theory (DFT) combining with the non-equilibrium Green functions (NEGF) method is applied to the study of the electronic transport properties for a Di-thiol-benzene (DTB) molecule coupled to two Au(111) surfaces. The dependence of the transport properties on the bias, the coupling geometry of the molecule-electrode interface, and the intermolecular interaction are examined in detail. The results show that the existence of the hydrogen atom at the end of the DTB molecule would significantly decrease the transmission coefficients, and then the differential conductance (dI/dV). By changing the position of the DTB molecule located between two electrodes a maximum value of calculated current is observed. It is also found that the intermolecular interaction will strongly influence the transport properties of the system studied.

关键词： non-equilibrium Green functions method, transmission spectrum, the molecular projected selfconsistent Hamiltonian, projected density of state.

WEIERSTRASS REPRESENTATION FORSURFACES WITH PRESCRIBED NORMALGAUSS MAP AND GAUSS CURVATURE IN H^3

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Chinese Annals of mathematics,Series B 2004年第4期25卷 567-586页

作者： SHISHUGUO Instituteofmathematics FudanUniversityShanghai200433China.

The author obtains a Weierstrass representation for surfaces with prescribed normal Gauss map and Gauss curvature in H3. A differential equation about the hyperbolic Gauss map is also obtained, which characterizes the relation among the hyperbolic Gauss map, the normal Gauss map and Gauss curvature. The author discusses the harmonicity of the normal Gauss map and the hyperbolic Gauss map from surface with constant Gauss curvature in H3 to S2 with certain altered conformal ***, the author considers the surface whose normal Gauss map is conformal and derives a completely nonlinear differential equation of second order which graph must satisfy.

关键词： Hyperbolic space Hyperbolic Gauss map Normal Gauss map Weier-strass representation Harmonic map

Optical waveguides in LiNbO_3 and stoichiometric LiNbO_3 crystals by proton exchange

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1479-1488页

作者： LI ShiLing College of Physics and Engineering, Qufu Normal university, Qufu 273165, china school of Physics and Microelectronics, shandong university, jinan 250100, china College of Physics and Engineering Qufu Normal University Qufu China school of Physics and Microelectronics Shandong University Jinan China

The formation of optical planar waveguides in LiNbO3 and stoichiometric LiNbO3 crystals by proton exchange was reported. The prism-coupling method was used to characterize the dark-line spectroscopy at the wavelength of 633 and 1539 nm, re-spectively. The mode optical near-field outputs from proton-exchanged LiNbO3 and SLN waveguides at 633 nm were presented. The mode field from stoichiometric LiNbO3 (SLN) waveguide is lighter and more uniform than that from LiNbO3 waveguide, which means the quality of the waveguide in SLN crystal is better than that of the LiNbO3 waveguide. For proton-exchanged LiNbO3 waveguides, the evo-lution of the refractive index profile with annealing was presented. The disorder profiles of Nb atoms in proton-exchanged LiNbO3 waveguides were obtained by Rutherford backscattering/channeling technique. It is shown that the longer the exchange time, the larger the displacement of Nb atoms.

关键词： optical waveguide proton exchange LiNbO3 crystal stoichiometric LiNbO3 crystal

SMALLEST g-SUPERSOLUTION FOR BSDE WITH CONTINUOUS DRIFT COEFFICIENTS

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Chinese Annals of mathematics,Series B 2000年第3期21卷 359-366页

作者： LIN QINGQUAN (school of mathematics and System Science, shandong university, jinan 250100, china.) PENG SHIGE(school of mathematics and System Science, shandong university, jinan 250100, china.) E-mail: Linqingquan@math. sdu. cn Peng@sdu. edu. cn school of mathematics and System Science Shandong University Jinan 250100 China

The authors prove the existence and uniqueness of smallest g-supersolution with an equality constrains on (y, z) for one demensional stochastic differential equations whose drift coefficients are continuous and linear... 详细信息

关键词： Backward stochastic differentail equation g-supersolution Constraint

THE MODIFIED METHOD OF CHARACTERISTICS WITH FINITE ELEMENT OPERATOR-SPLITTING PROCEDURES FOR COMPRESSIBLE MULTICOMPONENT DISPLACEMENT PROBLEM

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Journal of Systems Science & Complexity 2003年第1期16卷 30-45页

作者： YUAN Yirang (Institute of mathematics, shandong university, jinan 250100, china) (Instilute of mathematics Shandong University Jinan 250100

For the three-dimensional compressible multicomponent displacement problem we put forward the modified method of characteristics with finite element operator-splitting procedures and make use of operator-splitting,characteristic method,calculus of variations,energy method,negative norm estimate,two kinds of test functions and the theory of prior estimates and *** order estimates in L^2 norm are derived for the error in the approximate *** methods have been successfully used in oil-gas resources estimation,enhanced oil recovery simulation and seawater intrusion numerical simulation.

关键词： Multicomponent displacement 3-dimensional compressibility operator-splitting characteristics finite element optimal order L2 error estimates.

A polynomial algorithm for finding (g,f)-colorings orthogonal to stars in bipartite graphs

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Science china mathematics 2005年第3期48卷 322-332页

作者： LIU Guizhen & DENG Xiaotie Department of mathematics, shandong university, jinan 250100, china Department of Computer Science, The City university of Hong Kong, Hong Kong, china Department of mathematics Shandong University Jinan China Department of Computer Science The City University of Hong Kong Hong Kong China

Let G be a bipartite graph with vertex set V(G) and edge set E(G), and let g and f be two nonnegative integer-valued functions defined on V(G) such that g(x) ≤f(x)for every vertex x of V(G). A(g,f)-coloring of G is a generalized edge-coloring in which each color appears at each vertex x at least g(x) and at most f(x) times. In this paper a polynomial algorithm to find a(g, f)-coloring of a bipartite graph with some constraints using the minimum number of colors is given. Furthermore, we show that the results in this paper are best possible.

关键词： bipartite graph, (g, f)-coloring, (g, f)-factor, orthogonal coloring.

THREE-POINT BOUNDARY VALUE PROBLEMSFOR A CLASS OF THREE ORDER DIFFERENTIAL INCLUSIONS

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Systems Science and Mathematical Sciences 1998年第2期11卷 144-149页

作者： ZHANG Fubao(Department of mathematics, shandong university, jinan 250100, china) 山东大学数学系山东济南

Some existence theorems of three-point boundary value problems for a class ofthree order differential inclusions are obtained by means of the topological degree theory forset-valued mappings and an improved Wirtinger’s inequality. The results, even restrictedto the case of differential equations, have generized and improved on the related results in[1]. Particularlyt a problem raised in Remark 5 in if] is answered definitely.

关键词： Three-point boundary value differential inclusion topological degree.

Repetitious-Hot-Pressing Technique in Hot-Pressing Process

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Journal of Materials Science & Technology 2003年第5期19卷 486-488页

作者： Shixue SONG, Xing AI, Wei GAO and Jun ZHAO1)school of Mechanical Engineering, shandong university, jinan 250061, china2)school of Science, jinan university, jinan 250022, china school of Mechanical Engineering Shandong University Jinan 250061 China school of Science Jinan University Jinan 250022 China

A new pressing method was proposed for hot-pressing process. Experimental results indicated that the porosity in Al2O3/TiC/ Ni/Mo (hereafter called AI2O3/TiC composite) composite compacts decreases by 6% after adopting this new technique, compared to traditional hot-pressing technique under the same sintering temperature. The flexural strength and Vicker hardness increase from 883 MPa to 980 MPa and from 16 GPa to 21.1 GPa, respectively. A theoretical model was given to analyze the densification mechanism of the composite in the process of repetitious-hot-pressing.

关键词： Hot-pressing sintering Repetitious-hot-pressing sintering Composite