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31.
A two-dimensional network compound [Ce(DMF)4(H2O)][α-BW12O40]·H2O·(HDMA)2 (HDMA = protoned dimethylamine, DMF = N,N-dimethylformamide) was synthesized from α-H5BW12O40·nH2O, Ce(NO3)3·6H2O and DMF and characterized by IR, UV spectra and TG-DTA. The result of the X-ray single crystal diffraction indicates that the crystal is monoclinic, space group P21/n, with unit cell dimensional: a = 1.1983(3), b = 2.4216(5), c = 1.9517(4) nm, β = 92.91(3)°, Z = 4, R1 = 0.07710, wR2 = 0.1416. Structural analysis indicates that every [Ce(DMF)4(H2O)]3-building block is surrounded by three adjacent [α-BW12O40]5-polyanions, meanwhile, every [α-BW12O40]5-polyanion interconnects with three neighboring [Ce(DMF)4(H2O)]3+ subunits, by making use of which two-dimensional network structure can be constructed. The result of thermogravimetric analysis manifests that the title compound has two-stage weight loss and the decomposition temperature of the title polyanionic framework is 560℃. The electrochemical analysis shows the title polyanion has three-step redox processes in the pH = 4-7 media. 相似文献
32.
GUO Hai-Ming NIU Hong-Ying ZHANG Xin-Ying WANG Jian-Ji 《有机化学》2003,23(Z1):107-108
The selective deprotection of geminal diacetates promoted by FeCl3·6H2O in the ionic liquid [bmim] [BF4] canbe efficiently achieved in good yields. The ionic liquid and the catalyst can be recycled easily and the process is car ried out under mild conditions. 相似文献
33.
NIU Jian-Jun CHENG Guang-Jin DONG Shao-Jun acoratory of Electroanalytical Chemistry ChangChun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin China 《中国化学》1994,12(1):1-10
The electrooxidation of Bilirubin (BR) in N,N'-dimethylformamide (DMF) and DMF + H_2O mixed solvent is investigated by voltammetry techniques, in situ rapid scan thin layer spectroelectrochemistry and in situ ESR spectroscopy. The data reveal that the oxidation process of BR undergoes many stages, which are all sped up by the introduction of water. The species of bilirubin taking part in the reaction is found to be changed from BR in DMF into BR' in the mixed solvents and the anodic peak potential is shifted correspondingly from +0.58 V to +0.026-+0.35 V (vs. Ag/AgCl, 1.0 M KCl). Free radicals and the dimerization of them are observed during the oxidation. 相似文献
34.
以AlCl3·6H2O、Na2MoO4·2H2O、CoCl2·6H2O和2,2'-联吡啶为主要原料合成了Anderson-B-型多金属氧酸盐[Co(2,2'-bipy)3]H[Al(OH)6(Mo6O18)]·5H2O,进行了红外光谱、紫外光谱、差热分析和单晶结构测定.晶体学测定结果表明,化合物属于三斜晶系,Pi空间群,晶胞参数:a=1.216 0(2),b=1.221 5(2),c=1.780 0(4)nm,α=86.83(3)°,β=88.76(3)°,γ=89.82(3)°,V=2.639 4(9)nm3,Z=2,R1=0.079 4,wR2=0.176 6.化合物结构分析表明,在晶体学上,标题化合物分子是由1个[Co(2,2'-bipy)3]2+配阳离子,1个H+离子,2个1/2[Al(OH)6(Mo6O18)]3-多阴离子和5个结晶水分子组成.多阴离子[Al(OH)6(Mo6-O18)]3-借助水分子和金属配离子通过超分子作用形成二维网状结构,网状结构之间又借助超分子作用形成三维无限伸展结构.差热分析表明,标题化合物的失重过程分为2步,多阴离子骨架破坏温度为547.5℃. 相似文献
35.
36.
A novel hybrid tungstocuprate(Ⅱ) [Cu(2,2'-bpy)3]2H4[CuW12O40]·6H2O(2,2'-bpy=2,2'-bipyridine) was synthesized via hydrothermal method and characterized using elemental analyses, IR, UV, XPS, TG-DSC, EPR, and X-ray single crystal diffraction. The structural analysis shows that the complex consists of an unusual Keggin-type polyoxoanion [CuW12O40]6- and a pair of chiral complex cations [Cu(2,2'-bpy)3] together with four protons and six crystallization water molecules, and the Keggin polyoxoanion is connected with [Cu(2,2'-bpy)3] via multiple C-H…O hydrogen bonds resulting in a dimer. 相似文献
37.
毒蕈碱受体激动剂的三维定量构效关系研究 总被引:1,自引:0,他引:1
采用比较分子场分析法(CoMFA)研究了55个四氢吡啶类毒蕈碱受体激动剂的三维定量构效关系(3D-QSAR), 建立了具有较强预测能力的3D-QSAR模型. 所得模型的交叉验证相关系数(q2)为0.507, 常规相关系数(R2)为0.982 , 标准方差为0.218, 说明系列化合物分子周围立体场和静电场的分布与生物活性间存在良好的相关性. 模型不仅很好地预测了训练集和测试集化合物的活性, 而且为设计活性更高的受体激动剂提供了理论依据. 相似文献
38.
LI Xue-mei ZENG Cheng-chu NIU Li-ting YAN Hong ZHENG Da-wei ZHONG Ru-gang 《高等学校化学研究》2006,22(6):747-752
IntroductionSubstituted diketo acid derivatives possess a varie-ty of biological properties, such as analgesic[1—3], anti-bacterial[4]as well as anti-inflammatory[3]. Very re-cently, the results of random screening of millions ofcompounds have shown that… 相似文献
39.
LU Zai-Sheng② NIU De-Zhong LI Xiu-Ling 《结构化学》2003,22(5)
1 INTRODUCTION 3-Hydroxy-2-methyl-4-pyranone (maltol) and 3-hydroxy-2-ethyl-4-pyranone (ethylmaltol) are nontoxic compounds that have been applied to bio- inorganic chemistry over several decades[1, 2]. Their iron(III) complexes are relevant to the control of iron levels in the human body. Such complexes have been assessed for the amelioration of anaemia[3] and their respective ligands have been tested for the removal of excess burdens of iron in diseases such as siderosis, haemochroma… 相似文献
40.