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61.
合成并表征了5-(4-乙酰氧基苯基),10,15,20-三苯基卟啉及其金属配合物,将它们作为修饰物,制得铂支撑的双层脂膜,用循环伏安法研究了抗坏血酸的氧化还原反应,并对其机理作了探讨。  相似文献   
62.
The reductive alkylation of amine with carbonyl compounds usingsodium hydrogen telluride has been investigated in recent years.Application of this method to the synthesis of N-alkyl derivativesof biologically important amino acids and their esters is described.  相似文献   
63.
Summary Dichloro bis(5) molybdenum catalyses the reduction of organic halides by sodium borohydride smoothly and selectively. The reactions with representative organic monohalides and polyhalides are investigated. The ease of reduction depends on the structure of the halide and the solvent used. alkoxycarbonyl and cyano groups are unattacked in the reaction. An oxidative addition-reductive elimination mechanism is tentatively suggested.  相似文献   
64.
The palladium-catalyzed reaction of simple arenes and nitriles provides good to excellent yields of aryl ketones or the corresponding hindered imines. The addition of a small amount of DMSO increases the yields dramatically. Both intermolecular and intramolecular examples of this process are successful. This novel chemistry is believed to involve palladium-catalyzed C-H activation, followed by carbopalladation of the nitrile.  相似文献   
65.
A novel compound, biotinylated 18β-glycyrrhetinic acid (BGA), was synthesized. It is a compound of 18β-glycyrrhetinic acid linked with biotin. Published in Khimiya Prirodnykh Soedinenii, No. 3, pp. 266–267, May–June, 2006. An erratum to this article is available at .  相似文献   
66.
The combination of matrix isolation infrared spectroscopic and density functional calculation results provides strong evidence that the transition metal monoxide cation, ScO+, coordinates five noble gas atoms in forming the [ScO(Ng)5]+ (Ng = Ar, Kr, or Xe) complexes in noble gas matrixes.  相似文献   
67.
Unlabeled fluoroimmunoassay with a europium chelate is described. The recommended method is simple because the complicated labeling process is omitted. The recovery of some samples ranges from 91 to 111%. The relative standard deviation of the method is less than 10%. The detection limit is about 10−10mol liter−1antigen.  相似文献   
68.
3,5-diBr-PADAP作锆(Ⅳ)显色剂的分光光度法研究与应用   总被引:2,自引:0,他引:2  
本文研究了在非离子表面活性剂存在下,用3,5-diBr-PADAP作锆显色剂的胶束增溶分光光度法。在pH1.0~2.0的HCl介质中,配合物吸光度最大且稳定,最大吸收值在610nm处。Zr(Ⅳ)与试剂形成1:2的配合物,摩尔吸光系数为1.10×10~5L·mol~(-1)·cm~(-1),zr(Ⅳ)量在0~30μg/25mL范围内遵守比尔定律。采用钽试剂一苯苹取分离法,适合于钽铌矿中微量锆的测定。  相似文献   
69.
α—Fe_2O_3是多种工业催化剂的主要成分,有反铁磁结构的特殊性.张和Matijevie的实验曾经发现,草酸在均匀α-Fe_2O_3胶体粒子上的吸附随温度的升高而增加,这可能暗示着草酸从物理吸附向化学吸附的过渡.考虑到磁学测量需要更为明显的表面效应,我们制备了较小的α-Fe_2O_3粒子,并测定其吸附草酸前后的磁化率变化。  相似文献   
70.
The molecular structure and binding, as well as infrared and electronic spectroscopic properties for the title complex Cu(mnt)(dmbpy)(mnt(2-)=maleonitriledithiolate, dmbpy=4,4'-dimethyl-2,2'-bipyridine) were studied in this paper. With semi-empirical PM3 and non-empirical DFT (B3LYP/6-311G*) methods, the molecular geometry of the complex was optimized and corresponding vibrational spectra in the gaseous state were obtained. The calculated results derived from DFT were more reasonable than those from PM3. The point group of Cu(mnt)(dmbpy) in isolated gaseous state was C(2), in which Cu(II) adopted a distorted tetrahedral geometry and the dihedral angle between the N(2)Cu and S(2)Cu planes was about 29.814 degrees. And a complete assignment to the IR spectra of such a complicated molecule was exhibited. With ZINDO/S method an electronic spectrum was calculated. The results showed that the calculated values generally agreed with the observed ones. And a detailed explain was made on its electronic spectra.  相似文献   
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