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131.
1 INTRODUCTION In 1984, thiolate ligand was successfully introduced into molybdenum carbonyl compound by the reaction of Mo(CO)6 with [Et4N]SR( R = C6H5, But) in a moderate condition[1]. From then on, a series of dinuclear molybdenum(0) carbonyl thiolate compounds have been synthesized and characterized by using a variety of thiolate ligands in our research group. It was found that a planar Mo2S2 unit is in the compound [Et4N]2[Mo2(CO)8(SC6H4-CH_3-p)2][2] (2) and a "butterfly" t… 相似文献
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The concept of the residence time τksp of an atom in a kink site has recently been suggested to understand the processes in electrochemical deposition of alloys
and intermetallic compounds. Different kink sites with different residence times must be defined for alloys and intermetallic
compounds. Based on this model, the finite Markov chain theory is applied to describe the selectivity of the growth process.
An analytical relationship between the alloy composition and the metal ion concentrations in the electrolyte is derived. General
model parameters are ratios g
i = K
ii/K
ij of equilibrium constants of the reaction of electrolyte ions with different kink sites on the surface (i, j representing different alloy components). These ratios are called selectivity constants. For simple conditions, the equation
g
i ≈ τii/τij connects the g
i values with the residence times. The theory is tested in the deposition of alloys Co-Ni (anomalous co-deposition) and Ni-Mo
(induced co-deposition). Additionally, Bi2Te3, an example of stoichiometric semiconductor deposition, is treated.
Published in Russian in Elektrokhimiya, 2006, Vol. 42, No. 10, pp. 1216–1223.
The text was submitted by the authors in English. 相似文献
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配位聚合物通常是通过某种有机配体与金属的配位几何选择以及无限网络的拓扑结构控制而形成的具有无限结构的化合物 [1] ,其结构新颖并具有不寻常的光电效应、非线性光学性能、磁性、超导及催化等诸多具有诱人应用前景的独特性能 .因此 ,近年来倍受化学家和材料学家的重视 [2~ 5] .以 Co为配位中心的配位聚合物若具有八面体构型 ,在一定条件下具有自旋转换能力 ,而且往往可与光电转换能力相关联 ,是一种潜在的新型信息存储材料 [6 ] .对于配位聚合物的形成 ,配体的选择最重要 . 4,4′-联吡啶及其衍生物是一种较好的刚性配体 ,相关的配位聚… 相似文献
137.
Two new alkaline-earth Nd selenite chlorides MNd10(SeO3)12Cl8 (M=Ca, Sr) were obtained using crystal growth from alkaline-earth chloride melts in quartz tubes. These new compounds crystallize in the orthorhombic system in space group C cca (#68). The compounds were studied by energy dispersive X-ray spectroscopy (EDX) and X-ray diffraction. It was shown that both compounds adopt the same structure type, constructed by complex [M11(SeO3)12]8+ slabs separated by chloride anion layers perpendicular to the longest cell parameter. The SeO3 groups show a pyramidal shape and may be described as SeO3E tetrahedra. Such SeO3 groups decorate the Nd-O skeletons forming the [M11(SeO3)12]8+ slabs. 相似文献
138.
Pt(PPh_3)_2Cl_2在碱性介质中,与一氧化碳直接进行还原及羰基化反应,得到五种膦取代的羰基铂配合物:Pt_5(μ_2-CO)_5(CO)(PPh_3)_4 1,Pt_3(μ_2-CO)_3(PPh_3)_3 2,Pt_3(μ_2-CO)_3(PPh_3)_4 3,Pt_4(μ_2-CO)_5(PPh_3)_4 4,以及Pt(Cl)(PPh_3)_2(COOCH_3) 5。经X-射线单晶衍射分析,确定了新的三核铂羰基簇2以及配合物5的分子结构。还讨论了1和5的生成机理。 相似文献
139.
用硒与尿素化合,新生的由杂环有机硒所组成的Zs-93硒剂治疗移植性S180肉瘤,有显著的抑瘤作用(P<0.01),其作用表现出一定的剂量效应,以5μg/只小鼠为最适,抑瘤率达60.76%,治疗组小鼠的T细胞、SOD活性均有增强。 相似文献
140.
Summary The purity of the investigational antibacterial Abbott-086719.1 (I) which is 8[(3S)-3-amino-1-pyrrolidinyl]-1-cyclopropyl-7-fluoro-9-methyl-4-oxo-4H-quinolizine-3-carboxylic acid hydrochloride is determined using gradient elution HPLC. The chromatographic separation was optimized and the chromatographic parameters critical to separation are discussed in detail. Most acceptable separations were achieved using an Alltima C18 column (5 m) measuring 4.6 mm I.D.×15 cm with 0.01M–0.03M citrate eluents which were modified with acetonitrile or with mixtures of acetonitrile and methanol. Related substances in I were determinable to 0.05%. Repeatability (RSD values) for determining related substances at levels of 0.50 to 0.06% ranged from ±1.9 to ±10%. Determinations of I in 5% dextrose in water and in hydroxypropyl methylcellulose were made using the same column and a simple isocratic system. The determination of I was stability indicating with precision (RSD values) of ±0.5% to ±2.0% and good agreement with theory for formulations containing I at 1.0 to 95 mg/mL concentrations. Recoveries of I from the vehicles were quantitative and linearity of the detector response of I was demonstrated to at least 0.10 mg/mL. 相似文献