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排序方式: 共有1076条查询结果,搜索用时 15 毫秒
41.
采用循环伏安法、旋转金盘电极和库仑电解等方法研究了金在酸性硫脲(TU)溶液中的阳极溶解过程。提出了金的阳极溶解机构。认为表面的Au(TU)_(ads)~ 的“化学溶解”步骤是过程的控制步骤。由此解释了旋转金盘电极的极化曲线出现电流峰以及金的溶解速度出现极大的原因。 相似文献
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YangLIU ZhiYingLI JingHongLI 《中国化学快报》2005,16(1):64-66
IrO2Ta2O5 (70%: 30%, molar ratio) electrodes (ITEs) were prepared by the thermal decomposition method. Typical “mud-cracked” surface and surface enrichment of Ta were observed. The determination of dopamine (DA) was carried out in the presence of ascorbic acid (AA). The detection limit of DA was 5~10 5 mol/L without the interference of AA. 相似文献
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ChangLuSHAO HongYuGUAN ShangBinWEN BinCHEN XingHuaYANG JianGONG YiChunLIU 《中国化学快报》2004,15(4):492-494
Thin PVA/cobalt acetate composite fibers were prepared by using sol-gel processing and electrospinning technique.After calcination of the above precursor fibers,Co3O4 nanofibers with a diameter of 50-150 nm could be successfully obtained.The fibers were characterized by SEM,FT-IR,WAXD,respectively. 相似文献
46.
NIU Jian-Jun CHENG Guang-Jin DONG Shao-Jun acoratory of Electroanalytical Chemistry ChangChun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin China 《中国化学》1994,12(1):1-10
The electrooxidation of Bilirubin (BR) in N,N'-dimethylformamide (DMF) and DMF + H_2O mixed solvent is investigated by voltammetry techniques, in situ rapid scan thin layer spectroelectrochemistry and in situ ESR spectroscopy. The data reveal that the oxidation process of BR undergoes many stages, which are all sped up by the introduction of water. The species of bilirubin taking part in the reaction is found to be changed from BR in DMF into BR' in the mixed solvents and the anodic peak potential is shifted correspondingly from +0.58 V to +0.026-+0.35 V (vs. Ag/AgCl, 1.0 M KCl). Free radicals and the dimerization of them are observed during the oxidation. 相似文献
47.
YUAN Song-Yue ZHAO ZhenChangchun Institute of Applied Chemistry. Academia Sinica Changchun Jilin CYU Zuo-LongChengdu Institute of Organic Chemistry. Academia Sinica Chengdu. Sichuan To whom correspondence should be addressed 《天然气化学杂志》1995,(3)
The surface basicity of Ti-La-Li multicoinponent oxides has been investigated by means of CO2-TPD. The experiment results show that C2 (C2H6 C2H4) selectivity is related to surface basic strength. The surface active oxygen species have also been characterized by means of XPS, O2-TPD and so on. It has been indicated that C2 selectivity and CH4 conversion are correlated with lattice oxygen and the adsorbed oxygen on the surface of the catalyst respectively In the O2-TPD experiments, it has also been found that there are three kinds of oxygen species on the surface of the series catalvsts, which are a (100℃ 750℃) Among them α-oxvgen causes deep oxidation whileβand γ oxygen species are related to oxidalive coupling of methane (OCM). 相似文献
48.
A novel organic-inorganic hybrid compound {[Cu(2,2′-bpy)2]2Mo8O26} has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group, Pna21,with a=2.4164(5),b=1.8281(4),c=1.1877(2)nm,V=5.247(2)nm^3,Z=4,and final R1=0.0331,wR2=0.0727.The structure consists of discrete {[Cu(2,2′-bpy)2]2Mo8O26} clusters,constructed from a β-octamolybdate subunit[Mo8O26]^4- covalently bonded to two [Cu(2,2′-bpy)2]^2 coordination complex cations via bridging oxo groups.In addition,the spectroscopic properties and thernal behavior of this compound have been investigated by spectroscopic techniques (UV-vis,IR,Raman and EPR spectra) and TG analysis. 相似文献
49.
镍钴复合氧化物的制备和析氧活性 总被引:1,自引:0,他引:1
用浸碱热分解法制备了具有较高析氧活性和稳定性的复合氧化物NiCo_2O_4。考察了涂液成分、热分解温度和涂覆次数对NiCo_2O_4析氧活性的影响;测定了氧在NiCo_2O_4从电极上的稳态电化学行为。 相似文献
50.
Bi-Sr-Ca-Cu-O超导材料中存在110K和80K2个超导相。其组成是Bi_2Sr_2Ca_2Cu_3O_y和Bi_2Sr_2CaCu_2O。但迄今为止,在按2223组成比合成的未掺杂Bi系超导材料中从未得到过纯的110K相,也未见过组成为2223,零电阻温度在100K以上材料的报道。为了探索形成110K相的最佳条件,本文以2223组成比为参考,合成了5个系列材料:Bi_xSr_2Ca_2Cu_3O_y,Bi_2Sr_xCa_2Cu_3O_y,Bi_2Sr_2Ca_xCu_3O_y,Bi_2Sr_2Ca_2Cu_xO_y,Bi_i Sr_uCa_yCu_wO_s。 相似文献