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71.
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Three dinuclear copper(I) complexes, [Cu2(µ‐Cl)2(1,2‐(PPh2)2‐1,2‐C2B10H10)2]·2CH2Cl2 ( 1 ), [Cu2(µ‐Br)2(1,2‐(PPh2)2‐1,2‐C2B10H10)2]·2THF ( 2 ) and {Cu2(µ‐I)2[1,2‐(PPh2)2‐1,2‐C2B10H10]2} ( 3 ) have been synthesized by the reactions of CuX (X = Cl, Br and I) with the closo ligand 1,2‐(PPh2)2‐1,2‐C2B10H10. All these complexes were characterized by elemental analysis, FT‐IR, 1H and 13C NMR spectroscopy and X‐ray structure determination. Single crystal X‐ray structure determinations show that every complex contained di‐µ‐X‐bridged structure involving a crossed parallelogram plane formed by two Cu atoms and two X atoms (X = Cl, Br, I). The geometry at the Cu atom was a distorted tetrahedron, in which two positions were occupied by two P atoms of the PPh2 groups connected to the two C atoms of carborane (Cc), and the other two resulted from two X atoms which bridged the other Cu atom at the same time. To the best of our knowledge, this is the first example of copper(I) complexes with 1,2‐diphenylphosphino‐1,2‐dicarba‐closo‐dodecaborane as ligand characterized by X‐ray diffraction. The catalytic property of the complex 3 for the amination of iodobenzene with aniline was also investigated. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
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矿物质对煤焦表面性质和煤焦—CO2气化反应的影响   总被引:9,自引:0,他引:9  
  相似文献   
76.
He  Shuiyang  Peng  Ke  Ning  Wei  Wang  Daqi  Shi  Qizhen 《中国科学:化学(英文版)》2005,48(1):9-13

A novel compound (NH4)2Y(H2O)8[PMo10V2O40]·10H2O has been prepared in an aqueous solution and characterized by elemental analysis, IR, and TG-DTG analysis. X-ray diffraction analysis was carried out on (NH4)2Y(H2O)8 [PMo10V2O40]·10H2O single crystal, which crystallizes in the monoclinic system of a space group P21/c witha=0. 9871 (3) nm,b=1. 5424 (5) nm,c=2.7924(9) nm, β = 94.183(5)° and Z=2. In the compound, a two-dimensional network is constructed by the PMo10V2O 5−40 anion and the Y(H2O) 3+8 cation building blocks via hydrogen bonding exhibiting the porous structure.

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77.
基于并联神经网络的烤烟内在质量分析方法   总被引:3,自引:0,他引:3  
高大启  吴守一 《分析化学》1998,26(10):1174-1177
提出了一种并联神经网络,能直接将烤烟主要化学成分测量数据转换为与香气,吃味,杂气,刺激性等人的感官评定指标相一致的结果。该方法不必预先假定数学模型,较常规数据处理方法有更广泛的适用性。应用实例表明,与感官评定方法相比,该方法在客观性,准确性等方面有显著出优越性。  相似文献   
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A series of diorganotin(IV) compounds of the type [R(2)Sn(pca)Cl](3)(R = CH(3); (n)Bu; C(6)H(5); C(6)H(5)CH(2); Hpca = 2-pyrazinecarboxylic acid), R(2)Sn(pca)(2)(mH(2)O)xnH(2)O (m= 1: R = CH(3), n= 2, R =(n)Bu, n= 0; m= 0, n= 0: R =(n)Bu, C(6)H(5), C(6)H(5)CH(2)) and (Et(3)NH)(+)[R(2)Sn(pca)(2)Cl](-)xmH(2)O (m= 0: R = CH(3), (n)Bu, C(6)H(5)CH(2); m= 1: R = C(6)H(5)) have been obtained by reactions of 2-pyrazinecarboxylic acid with diorganotin(iv) dichloride in the presence of sodium ethoxide or triethylamine. All compounds were characterized by elemental, IR and NMR spectra analyses. Except for compounds, and, the others were also characterized by X-ray crystallography diffraction analyses, which revealed that compounds and were trinuclear macrocyclic structures with six-coordinate tin(IV) atoms, compounds and were monomeric structures with seven-coordinate tin(IV) atoms, compounds and were polymeric chain structures with seven-coordinate tin(IV) atoms and compounds and were stannate with seven-coordinate tin(IV) atoms.  相似文献   
79.
A novel compound (NH4)2Y(H2O)8[PMo10V2O40]·10H2O has been prepared in an aqueous solution and characterized by elemental analysis, IR, and TG-DTG analysis. X-ray diffraction analysis was carried out on (NH4)2Y(H2O)8 [PMo10V2O40]·10H2O single crystal, which crystallizes in the monoclinic system of a space group P21/C with a=0.9871(3) nm,b=1.5424(5) nm,c=2.7924(9) nm,β=94.183(5)°and Z=2. In the compound, a two-dimensional network is constructed by the PMo10V2O405- anion and the Y(H2O)83 cation building blocks via hydrogen bonding exhibiting the porous structure.  相似文献   
80.
[Pd(L1)2(CH3CN)](PF6)2 (L1 = 1-n-butyl-3-(2-pyrimidyl)imidazolylidene, 3) and [Pd(L2)2](PF6)2 (L2 = 1-(2-picolyl)-3-(2-pyrimidyl)imidazolylidene 4), prepared via carbene transfer reactions of [Ag(L1)2]PF6 (1) and [Ag2(L2)2](PF6)2 (2) with palladium salts, respectively, have been fully characterized by 1H and 13C NMR spectroscopy and elemental analysis. The X-ray crystal structures of complexes 1-4 are reported. Complex 3 is an unusual pentacoordinated palladium complex, in which the palladium is coordinated by two imidazolylidene, two pyridine, and one acetonitrile molecule in a square-pyramidal geometry. The apical position is occupied by a pyrimidine nitrogen atom with a relatively long Pd-N distance (2.762(6) angstroms). Complex is a typical square-planar palladium complex with palladium surrounded by two pairs of cis-arranged pyridine and imidazolylidene ligands. The complexes exhibit good catalytic activities in the Heck coupling reaction of aryl bromides and activated aryl chlorides under mild conditions.  相似文献   
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