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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 1. chemistry and chemical Engineering college of Henan University Kaifeng 475001 China 2. changchun institute of {2. chemistry Chinese Academy of Sciences Changchun 130022 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.

PREPARATION AND PROPERTIES OF ETHYL-cYANOETHYL cELLULOSE/POLYAcRYLIc AcID cOMPOSITE FILMS WITH REFLEcTION cOLORS

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chinese Journal of Polymer Science 2001年第3期19卷 277-282页

作者： Yong Huang institute of chemistry,{2., Beijing 100080 china Laboratory of cellulose and Lignocellulosics chemistry Guangzhou institute of chemistry{2., Guangzhou 510650, china 中科院化学所北京

Ethyl-cyanoethyl cellulose [(E-cE)c]/acrylic acid (AA) becomes a cholesteric liquid crystalline solution withvivid colors when the (E-cE)c concentration is 42.wt%～52.wt%. (E-cE)c/polyacrylic acid (PAA) composites withcholesteric structure were prepared by polymerzing AA in (E-cE)c/AA liquid crystalline solutions. The layers of orderedpolymer chains in the cholesteric phase were inclined during polymerization and the degree of the inclination depended onthe polymerization temperature and the concentration of the solution before polymerization. The cholesteric structure in thecomposites could not be changed when temperature was lower than 100℃. cross-linking of the PAA in compositesimproved their water-resistance. The cholesteric order of the composites without cross-linking was destroyed when theywhere immersed in water. The color derived from the selective reflection of the cholesteric phase of the cross-linkedcomposites turned from blue to red after the composites absorbed water. The color of the composites could be returned to theoriginal one when the absorbed water was removed from the swollen composites.

关键词： cholesteric structure composites Selective reflection Liquid crystalline solutions

SYNTHESIS AND cHARAcTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLEcULAR WEIGHT

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chinese Journal of Polymer Science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan institute of chemistry{2., Beijing 100080 china chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Over 2.x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation

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) chinese AcAD ScI INST APPL MATHBEIJINGPEOPLES R CHINA

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.) chinese Acad Sci Changchun Inst Appl Chem Changchun 130022 Peoples R 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 1. chinese academy of sciences SKLLQG Institute of Earth Environment 710075 Xi’an China 2. chinese academy of sciences Guangzhou Institute of Geochemistry 510640 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 chinese Acad Sci Changchun Inst Appl Chem State Key Lab Polymer Phys & Chem Changchun 130022 Peoples R China

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

Principles and methods of quantitative analysis on b-axis disorder in 2.: 1 dioctahedral phyllosilicate

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chinese Science Bulletin 1997年第22期42卷 1908-1912页

作者： WANG Ling and ZHANG Zhenyu1. changsha institute of Geotectonics,{2., changsha 410013, china 2. institute of Geology,{2., Beijing 10002., china changsha institute of Geotectonics Chinese Academy of Sciences Changsha China institute of Geology Chinese Academy of Sciences Beijing China

IN XRD patterns of clay minerals, a phenomenon that strong peaks often have (00l) and(hkl) (k=3n) indices and show symmetric figures can be seen commonly, while a minorityof reflection peaks (hkl) (k≠3n) are comparat... 详细信息

关键词： b-axis disorder pyrophvllile 2 phyllosilicate clay minerals dioctahedral minerals orientating structure of hy-droxyls crystal structure analysis DTA-TG.