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31.
《Electroanalysis》2006,18(1):44-52
The electrochemical oxidation of cobalt(II) at gold, boron‐doped diamond, basal and edge plane pyrolytic graphite, and highly oriented pyrolytic graphite electrodes in aqueous solutions containing NH3 has been studied using cyclic voltammetry, with subsequent chemical and electrochemical processes explained in detail. Furthermore, the electro‐reduction of [Co(NH3)6]3+ in the presence of different electrolytes has also been studied to obtain a better understanding of the oxidation pathway of the Co(II)‐ammine complexes. In aqueous solution the mechanism can be described by the following scheme: 相似文献
32.
We have determined the crystal structure of the title compound, which has a triclinic cell with cell parameters of , , , α=76.617°, β=84.188°, γ=74.510° and space group . The crystal structure suggests the chemical formula CoMoO4·3/4H2O. The structure consists of MoO4 tetrahedra and CoO6 octahedra, confirming the earlier X-ray absorption near-edge spectroscopic (XANES) investigation on the hydrate. The comparison of the crystal structures of the hydrate and the α-,β-, and hp-phases shows that the hydrate exhibits metal cation coordinations similar to those of the β-phase, but had arrangements of CoO6 and MoOn polyhedra similar to those of the hp-phase. 相似文献
33.
Liliana Cseh Carol Csunderlik Ingo Pantenburg Gerd Meyer Otilia Costisor 《无机化学与普通化学杂志》2003,629(6):985-988
The complex Co(C14H13NO)2Cl2 with the protonated N‐salicylidene‐p‐toluidine ligand was synthesized from an ethanolic solution of CoCl2·6H2O and N‐salicylidene‐p‐toluidine. The crystal structure was determined from X‐ray single crystal data (monoclinic, space group Cc, a = 1496.2(3) pm, b = 1257.4(4) pm, c = 1544.6(3) pm, β = 115.01(1)°, Z = 4). Co2+ adopts a distorted tetrahedral geometry. The UV‐Vis and IR spectra of the complex are discussed. 相似文献
34.
A thiophene-functionalised macrocyclic ligand trans-6,13-dimethyl-6-((thiophen-3-ylmethyl)amino)-1,4,8,11-tetraazacyclotetradecane-13-amine (L1) has been prepared and complexed with CoIII. The ligand L1 binds as a pentadentate in the crystallographically characterised complexes [CoL1(OAc)](ClO4)2 and [CoL1Cl]Cl2. Electro-copolymerisation of [CoL1Cl]Cl2 with 3,4-ethylenedioxythiophene (EDOT) in a 1:2 ratio on a preformed poly-3,4-ethylenedioxythiophene (PEDOT) film resulted in metal–polymer hybrid films of high quality, consistency and uniformity in appearance. The copolymerised films were characterised by XPS indicating a 1:11 ratio of incorporation of complex to EDOT. Electrochemistry of the Co-PEDOT film (cast on an indium-doped tin oxide working electrode) in water revealed a CoIII/II redox couple at a potential ca. −600 mV (vs Ag/AgCl) which is similar to that seen in solution for the monomeric aqua complex [CoL1(OH2)]3+. 相似文献
35.
36.
Wolfgang Dietzsch Norman V. Duffy Aaron M. Lee Brian W. Skelton Allan H. White 《无机化学与普通化学杂志》2006,632(15):2419-2423
The consequences of replacement of the symmetrically chelate ligands in [M(E2CNR2)3] (E = S, Se) complexes of potential 32 symmetry by analogous mixed S,Se unsymmetrical chelates are explored for both small (M = Co) and large (M = In) metal atoms, and R = primary (Et) and secondary (iPr) alkyl substituents by way of low‐temperature single crystal X‐ray studies of [(Co(SSeCNEt2)3] ([Co(Se2CNEt2)3] also determined as datum), and [In(SSeCNR2)3], R = Et, iPr. The structure of [(iPr2N·CS·Se)2] is also recorded. 相似文献
37.
有关Co(Ⅱ)、Ni(Ⅱ)萃取分离的研究一直受到人们的重视。Preston报导了硫氰酸季铵盐(Q~ SCN-)萃取Co(Ⅱ)、Ni(Ⅱ)的平衡研究,认为Co(Ⅱ)的萃合物组成为Q_2Co(SCN)_4.本文用上升液滴法技术考察了Co(Ⅱ)/0.10mol·L~(-1)SO_4~(2-)/QSCN-煤油体系在298±1K条件下萃取速率R与CoSO_4、SO_4~(2-)和QSCN浓度的关系,确定了正向初始萃取速率方程,拟定了速控步骤。 相似文献
38.
偏最小二乘法在原子吸收光谱分析中的应用——钴和铟的同时测定 总被引:4,自引:1,他引:3
本文用偏最小二乘法(PLS)校正了火焰原子吸收分析In252.137nm对Co252.136nm的吸收线重叠干扰,对混合样中Co和In的含量进行了测定,结果令人满意。 相似文献
39.
We have prepared polycrystalline samples of Sr3YCo4O10.56, Sr2.4Ca0.6YCo4O10.54, and Sr3YCo3.76Mn0.24O10.59, and found that these materials show unusual impurity effects on their transport and magnetic properties. A tiny amount of impurities such as Mn or Ca suppresses room-temperature ferromagnetism of Sr3YCo4O10.56. With the suppression, their resistivities and thermopowers are also dramatically changed. We propose that the unusual impurity effects are caused by the suppression of orbital ordering. 相似文献
40.
Chun Chun ZHANG Wei ZENG Jian Zhang LI Sheng Ying QIN* Department of Chemistry Sichuan University Chengdu 《中国化学快报》2003,(6)
It is well known that the study on biomimetic oxygen carriers not only has important theoretic significance to discover the mechanism of reversible bonding, activating oxygen as well as the oxidation reaction in organism, but also has potential application in separating oxygen from air and realizing the high efficiency and selectivity of catalytic oxidation reaction under a mild condition1. Metal- porphyrin and metal- phthalol- gaunine have been extensively used as biomimetic oxygen carriers u… 相似文献