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Synthesis and Crystal Structure of a New cis-Dioxovanadium (V) Complex with Pyruvic Acid Isonicotinyl Hydrazone (PAINH)

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Chinese Journal of Structural Chemistry 2006年第2期25卷 219-223页

作者： CHEN Rui-Jin ZHOU Yin-Zhuang HU Dai-Di TU Shu-Jie XIAO Ling-Mei DePartment of Chemistry Capital Normal University Beijing 100037 China

A new cis-dioxovanadium （V） complex [VO2（C9H8N3O3）]（C5H5N） involving a carboxyl group coordination employing a tridentate Schiff Base derived from pyruvic acid and isonicotinyl hydrazide is reported. This complex crystallizes in triclinic, space group P1^- with a = 7.3522 （12）, b = 7.8376（13）, c = 14.898（2） ,A°, a = 84.010（2）, β = 86.568（2）, γ= 64.586（2）°, V = 771.1（2）A °^3 ,Z = 2, F（000） = 376, Mr = 368.22, D, = 1.586 g/cm^3, g = 0.677 mm ^-1, R = 0.0421 and wR = 0.1253. The vanadium atom of the dioxovanadium （V） is five-coordinated to furnish a distorted trigonal bipyramid geometry.

关键词： dioxovanadium complex pyruvic acid isonicotinyl hydrazone (PAINH),crystal structure

A NUMERICAL SIMULATION OF CHANNEL RESERVOIRS CONTAINING VERTICAL AND HORIZONTAL WELLS

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Journal of Hydrodynamics 2006年第5期18卷 527-536页

作者： LIU Fu-ping WANG Xu-song WANG Jun WANG An-ling beijing Institute of Graphic Communication Beijing 102600 China Institute of Geology and Geophysics Chinese Academy of Sciences Beij ing 100029 China

In this article, the bounding surfaces of channels were modeled by Bayesian stochastic simulation, which is a boundary-valued problem with observed valley erosion thickness at the locations of wells （hard data）. In this study, it was assumed that the cross-section of the channel shows a parabolic shape, and the case that the vertical well and the horizontal well are located in the channel was considered. Peaceman＇s equations were modified to simultaneously solve both the vertical well problem and the horizontal well problem. In porous media, a 3D fluid equation was solved with iteration in the spatial domain, which had channels, vertical wells, and horizontal wells. As an example, the spatial distributions of pressure were calculated for channel reservoirs containing vertical and horizontal wells.

关键词： fluid equations in porous media porosity channel reservoirs numerical simulation heterogeneous media hrizontal well vertical well

Synthesis and Crystal Structure of an Unusual Dodecacoordinated Lanthanum Complex by Phenanthroline and Nitrate (phenH)_2[La(NO_3)_5(phen)]·CH_3OH

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Chinese Journal of Structural Chemistry 2011年第5期30卷 690-696页

作者：邓玉恒高国然刘娟刘灏 Department of Chemistry Capital Normal University

Lanthanum complex （phenH）2[La（NO3）5（phen）]·CH3OH （1, phen=phenanthroline） was synthesized and characterized by single-crystal X-ray diffraction. The title compound crystallizes in the monoclinic system, space group P21/c with a=20.3040（3）, b=10.7091（1）, c=19.0771（2）, β=102.090（1）°, V=4056.07（8）3, Z=4, Dc=1.676 g/cm3, μ= 1.142 mm-1, F（000）=2056, the final R=0.0346 and wR=0.0793 for 9981 （Rint=0.0358） independent reflections. The mononuclear complex 1 consists of four parts： two phenH＋ cations formed by the protonation of phen, one complex anion [La（NO3）5（phen）]2-, and one solvent methanol molecule. The complex anion contains one phen and five nitrate ligands which both chelate the center La（III） ion, adopting a distorted twelve-coordinated icosahedral geometry. The cations, anion and solvent molecule are linked together by hydrogen bonds. One of the protonated phenanthrolines （phenH＋） acting as cation connects to the anion via N–H…O hydrogen bond directly, and the other one links to the anion through an intermediate solvent CH3OH via N–H…O and O–H…O hydrogen bonds. By the plentiful additional weak C–H…O intermolecular hydrogen bonds, the compound molecules construct a two-dimensional layer structure.

关键词： lanthanum complex phenanthroline twelve-coordination crystal structure

Synthesis, Crystal Structure and Properties of a Novel Vanadium(Ⅴ) Oxoperoxo Complex Incorporating a Tridentate Hydrazone Ligand

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Chinese Journal of Structural Chemistry 2012年第2期31卷 185-190页

作者：耿磊珍邢婧周荫庄 Department of Chemistry Capital Normal University

A novel vanadium（V） oxoperoxo complex [VOO2（APTCH）（CH3OH）] （HAPTCH = 2-acetylpyridine thiophene-2-carboxylic hydrazone） has been synthesized and characterized by IR, TGA and X-ray single-crystal structure determination. The complex crystallizes in the monoclinic system, space group P21/c with a = 11.232（2）, b = 10.762（2）, c = 112.613（3）, β = 99.44（3）°, V = 1504.1（5）3, Dc = 1.657 g·cm-3, Z = 4, F（000） = 768, μ = 0.827 mm-1, the final R = 0.0392 and wR = 0.1073 for 2266 observed reflections with I 〉 2σ（I）. Single-crystal X-ray diffraction studies reveal that the vanadium（V） is coordinated by a tridentate ligand, methanol molecule and peroxo group to form a pentagonal-bipyramidal geometry. The crystal structure is stabilized by intermolecular hydrogen bonds of O-H···N and C-H···O.

关键词： vanadium(V) oxoperoxo complex hydrazone crystal structure TGA

Electrochemical performance of SrF_2-coated LiMn_2O_4 cathode material for Li-ion batteries

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中国有色金属学会会刊：英文版 2007年第6期17卷 1324-1327页

作者：李建刚何向明赵如松 School of Chemical Engineering Beijing Institute of Petrochemical Technology Institute of Nuclear and New Energy Technology Tsinghua University

SrF2-coated LiMn2O4 powders with excellent electrochemical performance were synthesized. The electrochemical performance of SrF2-coated LiMn2O4 electrodes was studied as function of the level of SrF2 coating. With increasing the amount of the coated-SrF2 to 2.0% (molar fraction), the discharge capacity of LiMn2O4 decreases slightly, but the cycleability of LiMn2O4 at elevated temperature is improved obviously. In view of discharge capacity and cycleability, the 2.0% (molar fraction) coated sample shows optimum cathodic behaviors. When being cycled at 55 ℃, as-prepared LiMn2O4 remains only 79% of its initial capacity after 20 cycles, whereas the 2.0% (molar fraction) coated sample shows initial discharge capacity of 108 mA·h/g, and 97% initial capacity retention.

关键词：锂离子电池表面涂层 LiMn2O4 电气化学性质

Synthesis and Characterization of Three Vanadium(Ⅴ) Complexes Incorporating Tridentate Hydrazone Ligands of Thiophene-2-carboxylic Hydrazide and 2-Furoic Acid Hydrazide

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Chinese Journal of Structural Chemistry 2012年第4期31卷 562-568页

作者：耿磊珍邢婧魏玮周荫庄 Department of Chemistry Capital Normal University

Divanadium（Ⅴ） complex [VO（aptch）（μ-OCH3）]2（1） and two monovanadium（Ⅴ） complexes [VO（apfah））（OEt）]（2a and 2b,H2aptch = 2-hydroxyacetophenone thiophene-2-car-boxylic hydrazone,H2apfah = 2-hydroxyacetophenone 2-furoic acid hydrazone） have been synthesized and ***-crystal X-ray diffraction studies reveal that 1 is a cen-trosymmetric dimer bridged by two methoxido *** 1 crystallizes in the monoclinic crystal system,space groups P21/c with a = 7.4825（4）,b = 17.0928（11）,c = 11.6961（7） ,β = 98.172（4）o,Z = 2,F（000） = 728,μ = 0.829 mm-1,the final R = 0.0457 and wR = 0.1137 for 2654 observed reflections with I 〉 2（I）.The vanadium（V） is coordinated to the tridentate ligand,ethanol molecule to form a distorted square-pyramidal geometry,complexes 2a and *** 2a and 2b have the same asymmetric unit,they belong to different space *** 2a crystallizes in the monoclinic crystal system,space groups P21/n with a = 10.2293（2）,b = 15.6660（3）,c = 10.6298（2） ,β = 116.259（1）o,Z = 4,μ = 0.676 mm-1;complex 2b crystallizes in the triclinic crystal system,space groups P with a = 8.2808（4）,b = 9.4704（5）,c = 10.0819（5） ,α = 86.133（3）,= 81.956（3）,γ = 80.248（3）o,Z = 2 and μ = 0.670 *** hydrogen bonds are found to exist in 2b *** crystal structure is stabilized by intermolecular hydrogen bonds of C-H···O.

关键词： vanadium(Ⅴ) complex hydrazone synthesis crystal structure

Synthesis,Crystal Structure and Interaction with DNA of a Novel Chromium(Ⅲ) Complex Containing Salicylaldehyde Semicarbazone

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Chinese Journal of Structural Chemistry 2009年第7期28卷 789-796页

作者：岳蕾周荫庄刘金丽屠淑洁肖岭梅 Department of Chemistry Capital Normal University

The novel chromium（Ⅲ） complex with salicylaldehyde semicarbazone was synthesized and characterized by IR spectra and single-crystal X-ray diffraction analysis. The crystal belongs to the orthorhombic system, space group Pbca with a = 8.9849（13）, b = 12.0475（16）, c = 34.522（5）A, V = 3736.9（9）A3, Z = 8, C16H18C1CrN6O5, Mr= 461.81, De= 1.642 g/cm^3, F（000） = 1896,A（MoKα） = 0.799 mm^-1, the final R = 0.0370 and wR = 0.0827 for 2908 observed reflections with I 〉 2σ（I）. The interaction between the chromium（Ⅲ） complex with calf thymus DNA （Ct-DNA） has been investigated by absorption spectroscopy, fluorescence spectroscopy and viscosity measurements. The results indicated that the complex was bonded to Ct-DNA through a non-classical intercalative mode.

关键词： chromium(Ⅲ) complex semicarbazone crystal structure calf thymus DNA

Synthesis and Structural Characterization of a Tetranuclear Copper Complex with 2-Amino-1,3-thiazole

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Chinese Journal of Structural Chemistry 2010年第12期29卷 1818-1823页

作者：邓玉恒丁彦峰刘娟单晓晨 Department of Chemistry Capital Normal University

The title tetranuclear complex,（μ4-oxo）-hexakis（μ2-chloro）-tetrakis（2-amino-1,3-thiazole-N）-tetra-copper（ii） [Cu4（μ4-O）（μ-Cl）6L4]（1,L=2-amino-1,3-thiazole） was synthesized by the reaction of CuCl2·2H2O with 2-amino-1,3-thiazole in methanol and characterized by IR spectra and X-ray *** 1 crystallizes in triclinic,space group P1 with a=9.7137（2）,b=10.7005（2）,c=14.6505（2）,α=83.9550（10）,β=82.0930（10）,γ=67.1640（10）°,V=1387.84（4）3,Mr=883.43,Z=2,μ=3.927 mm-1,Dc=2.1144 g/cm3,F（000）=868,R=0.0332 and wR=*** complex contains a tetrahedron of four CuII atoms coordinating to a central μ4-O atom,with the six edges of the tetrahedron bridged by six Cl *** Cu-O bond distances range from 1.910（2） to 1.918（2）,Cu-Cl from 2.3501（11） to 2.5924（10）,and Cu-Cu from 3.1003（6） to 3.1663（6）.The coordination geometries of the four coppers distort from trigonal bipramid to tetragonal pyramid with different distortion *** free animo groups of the ligands result in a lot of N-H···Cl and N-H···N intra-and intermolecular hydrogen bonds.

关键词： 2-amino-1 3-thiazole tetranuclear copper complex crystal structure

Corrosion resistance properties of AZ31 magnesium alloy after Ti ion implantation

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Rare Metals 2007年第2期26卷 142-146页

作者： CHEN Fei ZHOU Hai CAI Suo LV Fanxiu LI Chengming College of Mechanical Engineering Beijing Institute of Petrochemical Technology Beijing 102617 China Materials Science and Engineering School University of Science and Technology Beijing Beijing 100083 China

Magnesium alloys have a wide range of applications in industry; however, their corrosion resistance, wear resistance, and hardness are rather poor, which limit their applications. Ti ion was implanted into the AZ31 magnesium alloy surface by metal vapor vacuum arc （MEVVA） implanter. This metal arc ion source has a broad beam and high current capabilities. The implantation energy was fixed at 45 keV and the dose was at 9×10^17 cm^-2. Through ion implantation, Ti ion implantation layer with approximately 900 um in thickness was directly formed on the surface of AZ31 magnesium alloy, by which its surface property greatly improved. The chemical states of some typical elements of the ion implantation layer were analyzed by means of X-ray photoelectron spectroscopy （XPS）, while the cross sectional morphology of the ion implantation layer and the phase structure were observed by means of scanning electron microscopy （SEM） and X-ray diffraction （XRD）. The property of corrosion resistance of the Ti ion implanted layer was studied by the CS300P electrochemistry corrosion workstation in 3.5% NaCl solution. The results showed that the property of corrosion resistance was enhanced remarkably, while the corrosion velocity was obviously slowed down.

关键词： magnesium alloy ion implantation component distribution corrosion resistance