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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 325003, china 3. department of Chemistry, Lanzhou University, Lanzhou 730000, 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= 106.339(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.

Variable Separation Solution for(1+1)-Dimensional Nonlinear Models Related to Schrdinger Equation

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Communications in Theoretical physics 2004年第10期42卷 568-572页

作者： XU Chang-Zhi~(1,2) ZHANG Jie-Fang~11 Institute of Nonlinear physics,Zhejiang Normal University,Jinhua 321004,china2 department of physics and Mathematics,Jinhua Educational college,Jinhua 321000,china department of physics and Mathematics Jinhua Educational College Jinhua 321000 China

A variable separation approach is proposed and successfully extended to the(1+1)-dimensional *** new exact solution of(1+1)-dimensional nonlinear models related to Schr(?)dinger equation by the entranceof three arbitrary functions is *** special types of soliton wave solutions such as multi-soliton wave solution,non-stable soliton solution,oscillating soliton solution,and periodic soliton solutions are discussed by selecting thearbitrary functions appropriately.

关键词： variable separation approach (1+1)-dimensional nonlinear models solution of soliton

Global asymptotic stability of a two species competitive system with stage structure and harvesting

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Communications in Nonlinear Science and Numerical Simulation 2001年第2期6卷 81-87页

作者： Xinyu SONG and Lansun CHEN department of Mathematics, Xinyang teachers college, Henan 464000, china Institute of Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, china department of Mathematics Xinyang Teachers College Henan 464000 China Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 100080 China

The dynamics of a two species competitive system, where the species one has two stages, a immature stage and a mature stage with harvesting, and the growth of the species two is of Lotka-Volterra nature, is modelled by a system of retarded functional differential equations. We obtain the conditions for global asymptotic stability of three nonnegative equilibria and the threshold of harvesting mature population. The effect of the delay on the population at equilibrium and the optimal harvesting of mature population are also considered.

关键词： optimal harvesting stage structure competitive system global asymptotic stability.

On generalized k-syzygy modules

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Science china Mathematics 2007年第5期50卷 675-682页

作者： Chong-hui HUANG & Zhao-yong HUANG department of Mathematics, Nanjing University, Nanjing 210093, china college of Mathematics and physics, Nanhua University, Hengyang 421001, china department of Mathematics Nanjing University Nanjing China college of Mathematics and physics Nanhua University Hengyang China

In this paper, we first introduce the notion of generalized k-syzygy modules, and then give an equivalent characterization that the class of generalized k-syzygy modules coincides with that ofω-k-torsionfree modules. We further study the extension closure of the category consisting of generalized k-syzygy modules. Some known results are obtained as corollaries.

关键词： generalized k-syzygy module ω-k-torsionfree module extension closure

Molecular dynamics simulation of kink in 〈100〉 edge dislocation in body centred cubic iron

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Chinese Science Bulletin 2007年第16期52卷 2291-2296页

作者： CHEN LiQun1,2,WANG ChongYu2,3,4 & YU Tao2 1 college of Sciences,Central South University of Forestry & Technology,Changsha 410004,china 2 Central Iron and Steel Research Institute,Beijing 100081,china 3 department of physics,Tsinghua University,Beijing 100084,china 4 International Center for Materials physics,Chinese Academy of Sciences,Shenyang 110016,china college of Sciences Central South University of Forestry and Technology Changsha 410004 China

Using the molecular dynamics method,we have constructed two kink models corresponding to the 〈100〉{010} and 〈100〉{011} edge dislocations (EDs) in body centred cubic (bcc) Fe. It is found that the geometric structure of a kink depends on the type of edge dislocation and the structural energies of the atoms sites in the dislocation core region. The formation energies,migration energies and widths of the kinks in different types of EDs are calculated. The results show that formation and migration of the kink in the 〈100〉{010} edge dislocation are difficult. The 〈100〉{011} edge dislocation moves primarily through kink nucleation,rather than kink migration.

关键词：分子动力学边缘位移铁纽结结构

INTERIOR SPACETIME FOR THE QUANTUM BLACK HOLE AND ITS HOMOMORPHIC MAP

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Science in china,Ser.A 1986年第8期29卷 880-888页

作者：朱世昌 department of physics Shanghai teachers Univerity

The quantum gravitational effect in the Planck area is discussed for the dynamical and static cases. The interior metric of the quantum black hole is obtained. We prove the existance of the singularity-free quantum bl... 详细信息

关键词： INTERIOR SPACETIME FOR THE QUANTUM BLACK HOLE AND ITS HOMOMORPHIC MAP IT 占一

Persistence and Periodic Solutions of a System of Two Competing Species with Functional Response

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生物数学学报 1997年第1期 15-22页

作者： Dou Jiawei(department of Mathematics teachers college of Xi'an United University,Xi'an 710061,china)

This paper considers a nonautonomous system of two competing species with functional *** of two species can diffuse between two patches,and another is confined to one *** prove that the system can be persistent under some conditions and that if the system is a periodic system, then it has a strictly positive orbit which is globally asymptotically stable under the appropriate conditions.

关键词： Invdriant set ultimately bounded region persistence periodic solution

^(31)P solid-state NMR spectroscopy of VPO catalysts

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Chinese Science Bulletin 1997年第16期42卷 1370-1372页

作者： LI Mingxiu and YANG Shutaodepartment of Chemistry, Hebei teachers college, Shijiazhuang 050091, china department of Chemistry Hebei Teachers College Shijiazhuang China

VPO are well-known catalysts for the oxidation of n-butane to maleic anhydride. The catalytic behavior is influenced by several factors, such as the phase composition and the vanadium oxidation state of VPO catalysts. These catalysts have been characterized by means of XRD and XPS, but it is difficult to detect the presence of low concentrations of VOPO4 phases

关键词： 31P solid-state NMR spectroscopy VPO catalyst Tm n-butane maleic anhydride.

The Thermal Resistance and Its Measurement of a Modular Micro-channel Cooler

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Chinese Journal of Lasers 2000年第4期9卷 43-49页

作者： DAI Teli (department of physics and Information Technology of Chongqing teachers college, Chongqing 400047, china) 重庆师范学院重庆

The thermal impedance of Modular Micro channel Cooler (MCC) is the summation of the thermal impedances from heat source to silicon substrate, the silicon walls (fins), the interface between the PN junction bottom and indium layer, and the boundary layer of the coolant. The equations about the thermal conduction of MCC have been established and solved. The measurement of the thermal impedance of the MCC gave three curves that are the temperature rise versus the thermal power dissipated, the water flow versus the pressure across the device, and the wavelength versus the inverse water pressure. The calculated value of the thermal impedance from solving equations is in agreement with the measured value of the thermal impedance from the three curves.

关键词： modular micro cooler theranal impedance diode laser

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内战前美国南部商业经济的落后性及其原因

山东师范大学学报（人文社会科学版） 2002年第4期47卷 86-89页

作者：祝令建济宁师范专科学校历史系山东济宁272025

内战前 ,美国南部的商业经济从总体上看较为落后 ,主要原因在于 :南部内地市场狭小 ,商业资本缺乏 ;南部的城市没有担负起促进商业发展的重担 ;南方人的保守倾向和重农抑商观念抑制了商业经济的发展。

关键词：美国南部商业经济种植园经济商品零售业