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The title clusters [(PPh3)(p-BrC6H4CO2)2RuB10H8] (1) and [(PPh3)2Ru(PPh3)(p-BrC6H4CO2)RuB10H9] (2) have been prepared and characterized by elemental analysis, FT-IR, ^1H, ^13C NMR spectra and single-crystal X-ray diffraction analysis. The clusters crystallize in monoclinic system, space group C2/c, with a =2.569(4) nm, b= 1.546(2) nm, c= 1.927(3) nm ,8=95.11(2)°, Z=8, V=7.622(21) nm^3, Dc=1.533 Mg/m^3, F(000)=3472, S= 1.009, R= 0.0418, wR=0.0775 and triclinic system, space group P-l, with a=1.3142(3) nm, b= 1.3761(3) nm, c=1.8503(4) nm, a =90.445(4)°,β=105.950(4)°, γ108.980(4)°, Z=2, V=3.0251(12) nm^3, Dc = 1.434 Mg/m^3, F(000)= 1316, S=1.007, R=0.0464, wR=0.1175, respectively for 1 and 2. In the structures, both of the dusters are based on a closo-type C2v 1: 2 : 4 : 2 : 2 RUB10 stack with the metal occupying the unique six-connected apical position. In cluster 1, the metal center has three exo-polyhedral ligands: one triphenylphosphine and two dative oxygen atoms of p-bromobenzoates. The other oxygen atoms of two p-bromobenzoate are additionally bonded to B(2) and B(3) atoms respectively, resulting in two exo-cyclic five-membered Ru-O-C-O-B rings and engendering a symmetrical conformation. The cluster 2 is a bimetallic species in which the second ruthenium is bound to the {RUB10} center via one Ru-Ru bond and two {RuHμB} bridges resulting in one closo distorted exo-polyhedral Ru(1)-Ru(2)-B(3)-B(6) tetrahedron. 相似文献
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Zhang Ze Liu Qing-Liang Yang Jia-Xiang Wu Jie-Ying Tian Yu-Peng Jin Bao-kang Fun Hoong-Kun Chantrapromma Suchada Usman Anwar 《Transition Metal Chemistry》2003,28(8):930-934
The title complex [Mn2(phen)4(FCA)2](ClO4)2·H2O (1) (FCA = dianion of 3-ferrocenyl-2-crotonic acid, phen = 1,10-phenanthroline) has been prepared, and its structure determined by single crystal X-ray diffraction analysis. The structure consists of a dinuclear cation [Mn2(phen)4(FCA)2]2+, non-coordinated perchlorate anions and a water molecule. The two MnII ions are separated by 4.374 Å in the cation and are dicarboxylate-bridged by carboxylate ligands containing ferrocenyl units. Each FCA is bound to two MnII ions through carboxylate oxygens with the syn–anti bridging mode. The MnII ion is coordinated in an octahedral N4O2 geometry by two chelate phen ligands and two -carboxylate oxygen atoms. Electrochemical properties of (1) are discussed. 相似文献
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Quantum Game of Two Discriminable Coins 总被引:1,自引:0,他引:1
In some recent letters, it was reported that quantum strategies are more successful than classical ones for coin-tossing and
roulette game. In this paper, we will solve the quantum game of two discriminable coins. And we develop two methods, analogy
method and isolation method, to study this problem. 相似文献
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叠氮化钠对辣根过氧化物酶的荧光猝灭机制的研究 总被引:2,自引:0,他引:2
研究了辣根过氧化物酶 (HRP)和叠氮化钠 (NaN3 )作用前后的荧光光谱变化。探讨了HRP的荧光猝灭机制 ,首次运用了HRP的荧光猝灭行为确认了HRP和NaN3 之间生成了配合物。计算了HRP和NaN3 之间生成的配合物的形成常数为 7 9× 10 8L·mol-1,结合位点数为 1。研究还发现 ,NaN3 与HRP的结合 ,影响了分子构象 ,使酪氨酸和色氨酸残基的微环境受到不同程度的影响。 相似文献
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采用丝网印刷法制备了一种大面积的碳纳米管阴极,表征了阴极表面碳纳米管的形貌及分布.研究了该阴极在不同脉冲条件下的高压脉冲发射特性,分析了发射时阴极面等离子体产生和发射点的分布.研究表明:碳纳米管阴极的脉冲发射机制为爆炸电子发射,在平均场强为16.7V/μm的单脉冲电场下,阴极的最高发射电流密度为99 A/cm2.在平均场强为15.4 V/μm的双脉冲电场下,阴极的最高发射电流密度为267 A/cm2.碳纳米管阴极可以作为强流电子束源在高能微波器件中得到应用.
关键词:
强流脉冲电子束
碳纳米管
阴极
丝网印刷 相似文献
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