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101.
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
102.
ZhiQuanZHAO LiZengPENG YuLinLI 《中国化学快报》2005,16(3):290-292
The phenomenon of migration of the silyl groups from α-oxygen to β-oxygen in sodium aldol reaction was observed for the first time in this paper. 相似文献
103.
Jun-hua Shi Yuxun Zhou Ming-lei He Jian Jin Yi-chuan Xiao Jun-hua Xiao Dong-zhi Wei 《Chemistry of Natural Compounds》2006,42(3):325-327
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
104.
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
105.
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
106.
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
107.
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
108.
109.
Shen YF Fang CJ Peng ZH Li DC Zhou YH 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2005,62(1-3):132-139
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
110.
医用聚氯乙烯膜的等离子体表面改性 总被引:4,自引:0,他引:4
用两种不同气氛的辉光放电等离子体工艺对医用软质聚氯乙烯(PVC)膜进行了表面改性研究。结果表明,聚合性气氛的等离子体改性效果明显优于非聚合性气氛。平整致密的聚合膜对PVC增塑剂——邻苯二甲酸二辛酯的迁移和扩散起了阻挡作用,也使膜表面亲水性和表面张力极性成份增大,液固相界面张力减小,生物相容性得以改善。 相似文献