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Explicit Solutions for a (2+1)-Dimensional Toda Lattice with Two Discrete Variables

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Communications in Theoretical Physics 2007年第10期48卷 667-670页

作者： WANG Zheng-Yan YANG Xiao Department of Mathematics,zhengzhou university,zhengzhou 450052,China Department of Mathematics Zhengzhou University

An integrable(2+1)-dimensional Toda lattice with two discrete variables is investigated again,which isproduced from a compatible condition of the Lax *** Darboux transformation for its spectral problems is *** an appl... 详细信息

关键词： Toda lattice two discrete variables Darboux transformation explicit solution

Classification of hypersurfaces with parallel Mobius second fundamental form in S^(n+1)

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Science China Mathematics 2004年第3期47卷 417-430页

作者： HU Zejun LI Haizhong Department of Mathematics, zhengzhou university zhengzhou 450052, China Department of Mathematical Sciences, Tsinghua university, Beijing 100084, China Department of Mathematics Zhengzhou University Zhengzhou China Department of Mathematical Sciences Tsinghua University Beijing China

Let Mn(n≥2) be an immersed umbilic-free hypersurface in the(n+1)-dimensional unit sphere Sn+1. Then Mn is associated witha so-called M(o)bius metric g, and a M(o)bius second fundamental form Bwhich are invariants of Mn under the M(o)bius transformation groupof Sn+*** this paper, we classify all umbilic-free hypersurfaces withparallel M(o)bius second fundamental form.

关键词： parallel Mobius second fundamental form,hypersurface, Mobius metric, Mobius equivalence.

Kinetics of Protonolysis of o-Substituted Phenylmercuric Chlorides by HCl(NaI) in Ethanol

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Chinese Chemical Letters 1997年第4期8卷 319-322页

作者： Yu Lan WANG Yang Jie WU(School of Pharmaceutical Sciences, Beijing Medical university, Beijing, 100083)(zhengzhou university, zhengzhou, 450052) BEIJING MED UNIV SCH PHARMACEUT SCIBEIJING 100083PEOPLES R CHINA zhengzhou UNIV ZHENGZHOU 450052PEOPLES R CHINA

The kinetics of protonolysis of o-substituted phenylmercuric chlorides, o-XC6H4HgCl (X = H, CH3, CH3O, C2H5O, CF3, COOC2H5, Cl, Br, F, NO2), by hydrochloric acid in the presence of sodium iodide as catalyst have been studied in ethanol. The reaction has been found to be second order overall, first order in each reactant. The rate constants k measured at the same temperature may be arranged in the following order: C2H5O > CH3O > CH3 > H > CO2C2H5 > F > Cl > Br > CF3 > NO2.

关键词： Kinetics of Protonolysis of o-Substituted Phenylmercuric Chlorides by HCl NaI in Ethanol

Semisymmetric Cubic Graphs as Regular Covers of K3,3

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Acta Mathematica Sinica,English Series 2008年第3期24卷 405-416页

作者： Chang Qun WANG Tie Sheng CHEN Department of Mathematics,zhengzhou university,zhengzhou,450052,P.R.China Department of Mathematics Zhengzhou University Zhengzhou 450052 P. R. China

A regular graph X is called semisymmetric if it is edge-transitive but not *** G≤Aut X,we call a G-cover X semisymmetric if X is semisymmetric,and call a G-cover Xone-regular if Aut X acts regularly on its *** this paper,we give the sufficient and necessaryconditions for the existence of one-regular or semisymmetric Z-covers of ***,an infinite familyof semisymmetric Z×Z-covers of Kare constructed.

关键词： semisymmetric graph symmetric graph covering graph one-regular graph

Enhancement of H_2 Sensing Properties of In_2O_3-based Gas Sensor by Chemical Modification with SiO_2

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Chinese Chemical Letters 2004年第12期15卷 1509-1512页

作者： Zi Li ZHAN Deng Gao JIANG Jia Qiang XU School of Chemical Engineering, zhengzhou university, zhengzhou 450002 Department of Chemical Engineering, zhengzhou Institute of Light Industry,zhengzhou 450002 School of Chemical Engineering Zhengzhou University Department of Chemical Engineering Zhengzhou Institute of Light Industry

The sensitivity and selectivity to H_2 of a new In_2O_3-based gas sensor were improvedsignificantly by surface chemical modification. A dense layer of SiO_2 near the surface of the porousIn_2O_3 bead was formed by chemical vapor deposition(CVD)of diethoxydimethysilane(DEMS).The dense layer functioned as a molecular sieve, thereby the diffusion of gases with large moleculardiameters,except for H_2, was effectively controlled, resulting in a prominent selectivity and highsensitivity for H_2. The working mechanism of the sensor was also presented.

关键词： H_2 gas sensor indium oxide molecular sieve.

Enantiomeric Excess Determination of Amino Acids with Chiral Cyclopalladated Ferrocenylimine

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Chinese Chemical Letters 1999年第2期10卷 127-128页

作者： Xiu Ling CUI Yang Jie WU Liang Ru YANG(Department of Chemistry, zhengzhou university, zhengzhou, 450052) zhengzhou Univ Dept Chem Zhengzhou 450052 Peoples R China

An efficient NMR determination of the enantiomeric excess of the amino acids can be achieved using chloro-bridged dimer R- (+)-{Pd [(eta(5)-C5H5)Fe (eta(5)-C5H3CMe=NAr)] (mu-Cl)}2 (Ar=p-CH3C6H4) (R-1).

关键词： determination e.e% amino acids chiral cyclopalladated ferrocenylimine

SYNTHESIS AND CHARACTERIZATION OF ORGANOMONTMORILLONITE AND POLYAMIDE 66/MONTMORILLONITE NANOCOMPOSITES

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Chinese Journal of Polymer Science 2002年第6期20卷 551-557页

作者： Cheng-shen Zhu Xin Kang Su-qin He Liu-yang Wang Li-yun Lu College of Materials Engineering,zhengzhou university, zhengzhou 450052, China zhengzhou Univ Coll Mat Engn Zhengzhou 450052 Peoples R China

The montmorillonites (MMTs), layered, smectite-type silicates, were premodified by two different methods prior to the polymer melt intercalation. In one case MMTs were modified with cetyltrimethylammonium bromide (CTAB), and termed as organomontmorillonites (OMMTs); in the other case MMTs were modified by nylon, and the products were called modified montmorillonites (MMMTs). The effects of CTAB and nylon on the MMTs were investigated by using TG and WAXD. The results show that interlayer spacings of CTAB and nylon modified MMTs are larger than that of sodium MMTs. Then, polyamide 66 (PA 66)/MMT nanocomposites were obtained through the method of melt intercalation of polymers. The nanocomposites were characterized by WAXD, TEM and Molau experiments. The results indicate that the MMTs disperse homogeneously in the PA 66 matrix. The mechanical properties of nanocomposites, such as tensile properties and flexural properties, were also measured and show a tendency to increase with increase of MMT content and reach the maximum values at 5phr MMT content. The heat distortion temperature (HDT) of the nanocomposites (7 phr) is about 32 K higher than that of pure PA 66.

关键词： montmorillonite polyamide 66 nanocomposites melt intercalation

Studies on the Synthesis and Property of A New Podand-armed Calix[4]arene Derivative

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Chinese Chemical Letters 2000年第1期11卷 17-18页

作者： Yan Jun XING Zhi Xian ZHOU Li MA Zhen Wei LU( Chemistry Department, zhengzhou university, zhengzhou 450052) zhengzhou Univ Dept Chem Zhengzhou 450052 Peoples R China

A new ligand 25, 26, 27, 28-tetrakis[2-(o-methoxyphenoxy)ethoxy]calix[4]arene 3 was synthesized by direct base-strength-driven O-alkylation of calix[4]arene 1. 3 has been used as ionophore for cesium selective PVC mem... 详细信息

关键词： podand-armed calixarene cesium

Structure and magnetism of a porous three-dimensional metal-organic framework based on planar tetranuclear copper(Ⅱ) cluster units

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Science China Chemistry 2010年第10期53卷 2118-2122页

作者： LI HuiJun, ZHANG ErPeng, GUO QianQian, HOU HongWei & FAN YaoTing Department of Chemistry, zhengzhou university, zhengzhou 450052, China 1. Department of Chemistry Zhengzhou University Zhengzhou 450052 China

A porous three-dimensional copper(Ⅱ) metal-organic framework (MOF) {[Cu2(tci)(OH)(pip)0.5(H2O)]·6H2O}n (1) [tci = tris (2-carboxyethyl)isocyanurate, pip = piperazine] has been generated under hydrothermal conditions at 120 °C. Single crystal X-ray diffraction reveals that the polymer exhibits a novel three-dimensional framework based on planar tetranuclear copper(Ⅱ) cluster units. The variable temperature magnetic susceptibility data in the range 2-280 K show antiferromagnetic spin-spin coupling in the tetranuclear unit in complex 1. A theoretical fitting of the magnetic data gives J values of -31.3 cm-1, -30.8 cm-1, and 13.5 cm-1.

关键词： metal–organic framework tetranuclear copper cluster unit topology magnetism