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91.
Tetra-Schiff base macrocyclic compound containing benzo-12-crown-4 was synthesized via condensation of 2,6-diformyl-4-methyl-phenol with 4′,5′-diaminobenzo-12-C-4 promoted by proton. The compound was characterized by MS,IR ^1HNMR spectroscopy and elemental analysis. 相似文献
92.
A Pt microelectrode modified with nickel(II) polytetramethyldibenzo[b,i]tetraaza[14]annulene was prepared by electropolymerization of nickel(II) tetramethyldibenzo[b,i]tetraaza[14]annulene monomers and applied to determine sulfur dioxide in vitriol plant wastewater. For determination of SO2 with this electrochemically modified Pt microelectrode, the linear range was from 9.6 x 10(-6) to 2.4 x 10(-4) mol L-1, the sensitivity was 1.8 x 10(-4) A L mol-1, the detection limit was calculated to be 4.8 x 10(-6) mol L-1 (S/N = 3), the response time was less than 20 s and the relative standard deviation was found to be 2.1% on analyzing 4.8 x 10(-5) mol L-1 SO2 solution repeatedly (n = 7). These results demonstrated good accuracy compared with those obtained by the conventional iodimetric method. 相似文献
93.
94.
The atom transfer radical polymerization(ARP)of (-)-menthyl methacrylatc((-)-MnMA) mediated by CuCl/bipyridine and ethy1 2-bromopropionate or 1-phenylethyl bromide in THF system has been studied.The dependence of the specific rotation on molecular weight and the CD of Poly((-)-MnMA) thus obatined was investigated. 相似文献
95.
96.
Wei Ming XU Yu Guang WANG Zhen Hua CHEN Xian HUANG 《中国化学快报》2005,16(8):995-996
The development of organoselenium chemistry1 has been expanding rapidly during the last decades. Among them, organic selenides are key intermediates, for that they can be efficiently introduced, manipulated, and removed through selenoxide syn-elimination2. Our research group3 has been interested in the application of selenium in organic synthesis for several years. Isoxazolinyl substituted phenyl selenide 13a, although a β-H exists in the molecule, did not undergo selenoxide syn-elimination e… 相似文献
97.
In the present paper, Na_2SO_4-Al_2(SO_4)_3-H_2O system has been studied by ~(23)Na and ~(27)Al NMR quantitative method. It has been shown that the existence of double salt can be easily identified by this method. 相似文献
98.
De Bin ZHU Da XING Xian LI Lan ZHANG 《中国化学快报》2006,17(4):499-501
Current methods for single nucleotide polymorphism (SNP) analysis are time-consuming and complicated. We aimed at development of one-step real-time fluorescence mutant-allele-specific amplification (MASA) method for rapid SNP analysis. The method is a marriage of two technologies: MASA primers for target DNA and a double-stranded DNA-selective fluorescent dye, SYBR Green I. Genotypes are separated according to the different threshold cycles of the wild-type and mutant primers. K-rar oncogene was used as a target to validate the feasibility of the method. The experimental results showed that the different genotypes can be clearly discriminated by the assay. The real-time fluorescence MASA method will have an enormous potential for fast and reliable SNP analysis due to its simplicity and low cost. 相似文献
99.
丙二酸亚异丙酯及乙烯基硫代缩酮均是重要的有机合成试剂。而新近开发的5-(双甲硫基亚甲基)丙二酸亚异丙酯(1)既具有丙二酸亚异丙酯的环状结构,又具有乙烯基硫代缩酮的结构特征,它是一种多功能新的合成试剂。其最重要的性质是它可与多种亲核试剂发生加成反 相似文献
100.
表面修饰二氧化锡纳米微晶的制备与表征 总被引:10,自引:0,他引:10
制备了硅烷偶联剂KH-570表面修饰的SnO2纳米微晶,通过FT-IR、XPS、TEM和TG-DTA对其结构和表面特性进行表征和研究. FT-IR和XPS分析结果确证了KH-570与SnO2表面是以化学键合或物理吸附方式相结合,粒子表面存在酯基等有机官能团的红外吸收特征;观测到KH-570中Si原子的Si2s和Si2p谱线. TEM分析表明,表面修饰反应增强了SnO2纳米微晶的疏水性和分散性.由XPS和TG的实测数据探讨了纳米粒子具有较低包覆量的可能原因. 相似文献