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Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[cuLZn·cuLZn(H_2.)]·H_2.}_n

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Science china chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, cHENG Yanxiang2.& NIU Jingyang1 1. chemistry and chemical Engineering college of Henan University, Kaifeng 475001, china 2. changchun institute of applied chemistry, chinese academy of sciences, changchun 13002., china chemistry and chemical Engineering college of Henan University Kaifeng China changchun institute of applied {2. Chinese Academy of Sciences Changchun China

copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[cuLZn·cuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

δ-WAVE FOR 1-D AND 2.D HYPERBOLIc SYSTEMS

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Journal of computational Mathematics 1996年第3期14卷 256-262页

作者： S.L. Yang(institute of applied Mathematics,{2., Beijing, china) 中科院应用数学所北京

Here a new kind of nonlinear wave, which is called δ-wave, is described by some high resolution difference solutions for Riemann problems of one-dimensional (1-D) and two-dimensional (2.D) nonlinear hyperbolic systems in conservation laws. Some phenomena are numerically shown for the solutions of Riemann problems for 2.D gas dynamics systems

关键词： Zhang WAVE FOR 1-D AND 2.D HYPERBOLIc SYSTEMS

ELTA-WAVE IN A SIMPLE 1-D 2.x 2.HYPERBOLIc PROBLEM

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Journal of computational Mathematics 1996年第4期14卷 311-318页

作者： S.L. Yang(institute of applied Mathematics,{2., Beijing, china) institute of applied Mathematics Chinese Academy of Sciences Beijing China

A simple one-dimensional 2.x 2.hyperbolic system is considered in the *** model contains a linear hyperbolic equation, as well as a hyperbolic equation ofwhich the coefficients are about the solution of the linear one. The exact solution ispresented and discussed, then numerical experiments are given by TVD (or MmB)type schemes for Riemann problems. From the results, we know that the solutionsdo have δ-waves for some suitable initial data.

关键词： Zhang Figure DELTA-WAVE IN A SIMPLE 1-D 2 HYPERBOLIc PROBLEM

The Influence of Bond Valence on Bond covalency in RMn_2._5 (R=La, Pr, Nd, Sin, Eu)

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chinese chemical Letters 1999年第1期10卷 91-94页

作者： Zhi Jian WU Si Yuan ZHANG(changchun institute of applied {2., chinese academy of sciences, changchun 13002.) changchun Inst. of applied chemistry Chinese Academy of Sciences Changchun 130022 China

The relationship between bond valence and bond covalency in RMn2.5 (R = La, Pr, ***, Eu) has been investigated by a semiempirical method. This method is the generalization of thedielectric description theory of Phillips. Van Vechten, Levine and Tanaka scheme. The resultsindicate that larger valences usually result in higher bond covalencies, in good agreement with thepoint that the excess charge in the bonding region is the origin of formation of bond *** factors, such as oxidation state of elements, only make a small contribution to bondcovalency.

关键词： Bond valence bond covalency semiempirical method RMn_2._5

Magnetic properties of Jiaxian red clay sequences from northern chinese Loess Plateau and its paleoclimatic significance

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Science china Earth sciences 2005年第8期48卷 1234-1245页

作者： QIANG Xiaoke, AN Zhisheng, LI Huamei, cHANG Hong & SONG Yougui 1. SKLLQG, institute of Earth Environment,{2., Xi’an 710075, china 2. Guangzhou institute of Geochemistry,{2., Guangzhou 510640, china chinese academy of {2. SKLLQG Institute of Earth Environment Xi’an China chinese academy of {2. Guangzhou Institute of Geochemistry Guangzhou China

Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/southern chinese Loess Plateau, and it should be more arid in northern chinese Loess Plateau.

关键词： northern chinese Loess Plateau, red clay, magnetic property, paleoclimatic significance.

MELTING cRYSTALLIZATION BEHAVIOR OF NYLON 66

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chinese Journal of Polymer Science 2001年第3期19卷 237-246页

作者： Qing-xin Zhang Zhi-shen Mo State Key Laboratory of Polymer Physics & chemistry changchun {2. of applied chemistry chinese academy of sciences, changchun 13002., china 中科院长春应用化学所高分子物理与化学国家重点实验室吉林长春

Analysis of isothermal and nonisothermal crystallization kinetics of nylon 66 was carried out using differential scanning calorimetry (DSc). The commonly used Avrami equation and that modified by Jeziorny were used, respectively, to fit the primary stage of isothermal and nonisothermal crystallizations of nylon 66. In the isothermal crystallization process, mechanisms of spherulitic nucleation and growth were discussed. The lateral and folding surface free energies determined from the Lauritzen-Hoffman treatment are sigma = 9.77 erg/cm(2. and sigma (e) = 155.48 erg/cm(2., respectively; and the work of chain folding is q = 33.14 kJ/mol. The nonisothermal crystallization kinetics of nylon 66 was analyzed by using the Mo method combined with the Avrami and Ozawa equations. The average Avrami exponent (n) over bar was determined to be 3.45. The activation energies (DeltaE) were determined to be -485.45 kJ/mol and -331.2. kJ/mol, respectively, for the isothermal and nonisothermal crystallization processes by the Arrhenius and the Kissinger methods.

关键词： nylon 66 crystallization kinetics activation energy

Luminescence of RE^(3+) and energy transfer from Gd^(3+) to RE^(3+) (RE = Dy, Eu) in SrGdAlO_4:RE^(3+)

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chinese Journal of chemistry 1997年第1期15卷 60-67页

作者： LIU, Sheng-Li SU, QiangLaboratory of Rare Earth chemistry and Physics, changchun {2. of applied chemistry, chinese academy of sciences, changchun, Jilin 13002., china Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Spectral properties of Gd3+, Dy3+ and Eu3+ ions in SrGdAlO4 are reported in detail. A cooperative vibronic transition of Gd3+ and the emission from the higher 5DJ (J=1, 2. 3) levels of Eu3+ were observed. Energy transfer occurs from Gd3+ to Dy3+ and to Eu3+. The influence of Gd3+ and Dy3+ concentrations on the luminescence intensity is discussed.

关键词： Luminescence energy transfer rare earth aluminate

PREPARATION OF Pb-ca-Na MASTER ALLOY USING MOLTEN cHLORIDE SALT ELEcTROLYSIS

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中国有色金属学会会刊：英文版 1996年第2期6卷 18-19,21+25页

作者： Song Renying Wang Xingjie Luo Shumei Jiang chan Tang Dingxiang(changchun institute of {2. chemistry ,chinese academy of sciences, changchun 13002.) changchun institute of applied {2. Chinese Academy of Sciences Changchun 130022 China

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关键词： Pb-ca-Na master alloy molten chloride salt electrolysis preparation

copolymerization of N-4-Dibenzoylmethane Maleimide with Styrene

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chinese chemical Letters 1999年第9期10卷 787-788页

作者： Qing Hui cHU Meng Xian DING(changchun institute of {2. chemistry. chinese academy of sciences.changchun 13002.) changchun Inst. of applied chemistry Chinese Academy of Sciences Changchun 130022 China

The copolymer of N-4-dibenzoylmethane maleimide (p-DBMI) with styrene (St) was prepared and characterized by gel permeation chromatography, thermal analysis and spectroscopy.

关键词： N-4-dibenzoylmethane maleimide styrene copolymer