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31.
A. Müller E. Krickemeyer F. El-Katri D. Rehder A. Stammler H. Bgge F. Hellweg 《无机化学与普通化学杂志》1995,621(7):1160-1170
Simple Trithio- and Perthiocarbonato Complexes with Interesting Bond Properties: [E(CS3)2]2? (E = Sn, Zn, Cd), [E(CS3)3]3? (E = As, Sb, Bi, Co), {Cu(CS3)?}∞ and [Zn(CS4)2]2? By reactions of potassium trithiocarbonate ( 1 ) with solutions of zinc(II)- acetylacetonate, cadmium(II)-chloride, tin(II)-chloride, arsenic(III)-sulfide (suspension), antimony(III)-chloride, bismuth(III)-chloride and copper(II)-chloride in dimethyl sulfoxide, as well as of trisodium hexanitrito cobaltate(III) in water, and the precipitation of the complexes with an aqueous solution of tetraphenylphosphonium chloride the compounds (PPh4)2[Zn(CS3)2] ( 2 ), (PPh4)2[Cd(CS3)2] ( 3 ), (PPh4)2[Sn(CS3)2] ( 4 ), (PPh4)3[As(CS3)3] ( 5 ), (PPh4)3[Sb(CS3)3] ( 6 ), (PPh4)3[Bi(CS3)3] ( 7 ), (PPh4)3[Co(CS3)3] ( 8 ) and (PPh4)Cu(CS3) ( 9 ) have been isolated. (PPh4)2[Zn(CS4)2] · CH3NO2 ( 10 ) has been prepared by heating a solution of 2 in nitromethane to 60--70°C in presence of air. The reaction of 1 in dimethyl sulfoxide with an aqueous tetraphenylphosphonium chloride solution in presence of oxygen leads to (PPh4)2[C2S6] ( 11 ). The compounds have been characterized by spectroscopical studies (IR, Raman, UV/Vis, 113Cd/59Co-NMR), magnetic susceptibility measurements, powder diffractometry, elemental analyses and single crystal X-ray structure analysis ( 4 – 7 , 10 and 11 ). The difficult growing of single crystals has been reported in detail. For crystal data see Inhaltsübersicht. 相似文献
32.
The apparent molar volumes V of KCl, BaCl2, K2SO4, LaCl3, Co(en)3Cl3 [Tris(ethylenediamine)cobalt(III) chloride], K3Co(CN)6, K3Fe(CN)6, K4Fe(CN)6, and Ba3[Co(CN)6]2 have been determined at 25°C in both light and heavy water. The V values in D2O are systematically lower and increase more rapidly with salt concentration than the V in H2O. The volume of transfer from H2O to D2O as well as the partial molar volume at infinite dilution in both solvents have also been calculated. These results together with literature values for other electrolytes were used to estimate both of these quantities for D2O solutions of individual ions. The predictions of ion hydration models and ion-ion interactions are compared with experimental observations. 相似文献
33.
RongZhongYUAN ZuoLongYU MeiZhenQU 《中国化学快报》2003,14(7):755-758
A novel gel-like process has been developed for synthesizing LiaNi0.8Co0.2O2 powders,using citric acid as a chelating agent. This process improves the homogeneity of constituent cation and enhances their reactivity in the obtained precursor. The results of electrochemical test demonstrated that these materials exhibited excellent electrochemical properties. Its initial capacity reached 181.6 mAh/g and reversible efficiency at the first cycle is about 88.6%. 相似文献
34.
测定不同配比的氟氰菊酯与丙硫磷复配制剂(简称氯丙制剂)对褐棘蛾和马尾松毛虫幼虫的触杀毒力、共毒系数和增效配比,加工成不同比例的氯丙复合乳油,对两种供试昆虫进行了防治效果检验。结果表明,以有效成分间1:7的比例配制的氯丙复剂增效明显,成本较低,具有较理想的防治效果。 相似文献
35.
Rapid dissolution procedure for base-metals-bearing complex materials for quality control assessment
A less labour-intensive method, involving a mixture of 1.0 g MnO2 + 20 mL HCl (11), is proposed for decomposing seven ores and six metallurgical products for accurate and precise estimation of copper, lead, zinc, cobalt and nickel for quality control assessment. Twentyone international reference materials were also analysed. Results of regression analyses are presented and intermethod comparison studies reveal that the probability of results being different compared with a reference method was less than 1%. Sample decomposition is straightforward and the method has been found to be very simple, rapid and easily adaptable, as it involves no separation of the analyte from the matrix elements. 相似文献
36.
辅酶I(NAD+)在0.005moL/LTris 0.01moL/LNaCl溶液(pH7.0)中,于钴离子注入修饰碳纤维电极上出现一个S形的还原波,半波电位为-1.45V(vs.SCE)。峰电流与NAD+的浓度在2.38×10-5~4.76×10-4mol/L(r=0 9992)和4.76×10-4~1.78×10-3mol/L(r=0.9982)之间成线性关系,检出限为1.19×10-5mol/L,回收率在96.7%~103.4%之间。用线性扫描、循环伏安法研究了钴离子注入修饰碳纤维电极上NAD+的电化学行为。电极反应机理为:NAD++e NAD·;NAD·+e+H+ NADH;2NAD·→NAD2。另外,钴离子注入修饰碳纤维电极对NAD+具有电催化作用。 相似文献
37.
溶胶-凝胶-钴-邻菲啰啉修饰电极对一氧化氮的电催化氧化及其测定 总被引:3,自引:0,他引:3
报道了溶胶 凝胶 钴 邻菲口罗啉膜修饰电极的制备方法及其在一氧化氮(NO)检测中的应用,采用循环伏安法(CV)研究修饰电极的电化学特性,差示脉冲伏安法(DPV)对NO进行检测。该修饰电极对NO的电化学氧化具有很好的催化作用,使其氧化电位负移了210mV,氧化峰电流与NO浓度在5.6×10-8~2.8×10-5mol/L范围内呈良好的线性关系,相关系数r=0.999,检测限为1.4×10-8mol/L,且生物体内常见的干扰物质如抗坏血酸、NO2-和儿茶酚胺类神经递质的代谢物等不干扰测定。 相似文献
38.
钴铈复合金属氧化物催化剂上氧化亚氮催化分解性能研究 总被引:2,自引:0,他引:2
采用共沉淀法制备了一系列钴铈复合金属氧化物催化剂CoCex(x=0~0.2,x为Ce/Co摩尔比),进行了比表面积和XRD表征,并考察了它们对氧化亚氮催化分解反应的活性.结果表明,随着铈添加量的增加,催化剂上钴尖晶石相的衍射峰逐渐宽化,同时催化剂的比表面积逐渐增大;催化剂的活性随着铈添加量的增加先升高,然后下降,CoCe0.05催化剂表现出了最佳催化活性.在对CoCe0.05催化剂制备条件的考察实验中发现,共沉淀过程中控制pH值在9左右,于400 ℃焙烧得到的催化剂的活性最好.当反应气氛中存在O2或H2O时,CoCe0.05催化剂上N2O的分解反应受到抑制,但这种影响是可逆的,可能是由于它们与N2O在相同的活性位上存在竞争吸附. 相似文献
39.
A new Co(II) complex with tridentate Schiff base ligand with a N,N,O donor set has been synthesized and characterized by single X-ray technique and spectroscopic techniques. The thermochemical properties have been studied. X-ray structure analysis of the title compound Co(II)L2 [HL = 2-methyl-6-(2′-hydroxybenzylideneamino) pyridine] shows that the polyhedron around Co(II) is a distorted tetrahedron, and the self-assembly via intermolecular π-π interactions leads to a three-dimensional network. Crystal data for the title complex C26H22CoN4O2: Monoclinic, space group Ia, a = 11.741(7) Å, b = 8.149(5) Å, c = 22.764(16) Å, β = 98.530(12)°, V = 2154(2) Å3, Z = 4. 相似文献
40.
1 INTRODUCTION The tris(ethylenediamine) cobalt (Ⅲ) complex in which there are L and D configurations is one of the very interest cations due to the chirality among research complexes and the characterization of reaction on the ion-pair charge-transfer transitions. It has been mentioned in a lot of examples on the chirality and the structure, such as [L-Co(en)3]- [?Co(edta)]2Cl?0H2O[1], [(+)DCo(en)3]Cl3稨2O[2], [(+)-Co(en)3?-)-Cr(en)3]Cl?.1H2O[3], [()-Co(en)3] (SCN)3[4], [(+)D… 相似文献