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李俊霞  王建革  黄唯平 《结构化学》2011,30(10):1469-1476
Use of free air as oxidant and copper(II)chloride as catalyst,3,3'-di-tert-butylbi-phenyl-2,5,2',5'-diquinone(BBDQ)was prepared via catalytic oxidation of 2,2'-dihydroxy-3,3'-di-tert-butyl-5,5'-dimethoxy-biphenyl(di-BHA).The yield of reaction attained 95% and the selectivity for BBDQ was 100%.The single-crystal X-ray diffraction analysis reveals that the dihedral angle between two rings(benzene rings for di-BHA and quinone rings for BBDQ)changes from 89.8 to 45.3o,indicating the steric hindrance effects of methyl disappear in the oxidation process.The crystal structures of di-BHA and BBDQ are further confirmed by their spectral characterizations.The probable mechanism for this oxidation process is also discussed.  相似文献   
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以溴代十二烷和五甲基二乙烯三胺为原料,用微波辐射合成了新型三联季铵盐阳离子表面活性剂,探索了合成低聚表面活性剂的新途径,结果表明:最佳工艺条件为在98℃下,以正丙醇为溶剂,叔胺与溴代十二烷的mol比为2:5;反应8min结束.并对产物进行了化学分析、核磁共振氢谱、红外光谱表征,测定了产物水溶液的CMC值为0.06mmol/L及最低表面张力为38.4mN/m.  相似文献   
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A new cadmium(II) compound, {[Cd[μ-(4,4'-dps)]2(H2O)2]·(4-abs)2(H2O)2}n 1 (4,4'-dps = 4,4'-dipyridylsulfide, 4-abs = deprotonated 4-amino benzenesulfonic acid), has been synthesized and structurally characterized. It belongs to the orthorhombic system, space group Pbcn with a = 19.950(3), b = 10.6381(13), c = 18.055(2) , V = 3831.8(8) 3, Z = 4, C32H36CdN6O10S4, Mr = 905.31, F(000) = 1848, μ = 0.850 mm-1, Dc = 1.569 Mg/m3 , the final R = 0.0238 and wR = 0.0589 for 3080 observed reflections with I > 2σ(I). Complex 1 is a one-dimensional linear chain coordination polymer and the repeat unit is comprised of doubly charged cadmium complex cation, uncoordinated 4-aminobenzene sulfonate anions and water molecules. The cadmium(II) ion adopts a six-coordinate distorted octahedral geometry. Complex 1 is stabilized and linked into a three-dimensional layered structure through intermolecular O–H···O and N–H···O hydrogen bonds together with electrostatic force. The cyclic voltammograms and fluorescence spectrum of 1 were also measured. It shows one irreversible redox process and emits a very strong and sharp fluorescent band at about 341 nm.  相似文献   
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本文研究了基因表达式编程在重金属形态获取中的应用问题.利用改进的基因表达式编程和Shannon信息熵方法,验证了算法的高效性,获得了重金属形态预测模型并从该模型中获取了重金属的形态知识的结果.该新模型方法还可广泛用于其他时间序列预测问题的研究.  相似文献   
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