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51.
Quantitative enantiomeric analysis of chlorcyclizine,hydroxyzine, and meclizine by capillary electrophoresis 总被引:1,自引:0,他引:1
A simple capillary zone electrophoresis method was developed for the quantitative enantiomeric analysis of piperazine antihistamines with teratogenic suspicion in animals. Enantioseparation of chlorcyclizine, hydroxyzine, and meclizine was performed in glycine buffer (0.6 mol L-1; pH 3.00) with sulfated -cyclodextrin (5 mg mL-1) as a chiral selector; and the separated drugs were monitored by ultra-violet detector. The lower quantitation of the individual enantiomer is attainable at 10 µmol L-1, using an achiral piperazine drug (cyclizine) as internal standard. The method is simple and rapid with a short run time (<5 min) for the analysis of chlorcyclizine, hydroxyzine or meclizine enantiomers. 相似文献
52.
Teffo J Claveau C Kou Q Guelachvili G Ubelmann A Perevalov VI Tashkun SA 《Journal of Molecular Spectroscopy》2000,201(2):249-255
The 7000-8500 cm(-1) spectral region of (12)C(16)O(2) has been investigated using the high-resolution FT spectrometer of LPPM in Orsay. The two strongest bands in this region are the 10031 <-- 00001 and 10032 <-- 00001 bands centered at 8294 and 8192 cm(-1). Line intensities in these two bands and in the 40013 <-- 00001 and 40014 <-- 00001 bands have been measured. Using the method of effective operators, these line intensities have been included in a new fit of effective dipole-moment parameters to all available experimental data in the same spectral region of (12)C(16)O(2). The corresponding calculated line intensities of the 10031 <-- 00001 and 10032 <-- 00001 bands are compared with the experimental ones. Copyright 2000 Academic Press. 相似文献
53.
54.
Wen-Hua Zhang Xiu-Bao Wei Ping-Ning Jin Jun-Feng Kou Guang Yang 《Transition Metal Chemistry》2011,36(5):459-463
Reactions of 3(5)-methyl-5(3)-phenyl-1H-1,2,4-triazole (3-Me-5-Ph-tzH) with AgNO3 in the absence/presence of NH3 yield a mononuclear [Ag(3-Me-5-Ph-tzH)2]NO3·3H2O (1) and a polymeric [Ag(3-Me-5-Ph-tz)]n (2), respectively. Two structurally different infinite chains, however, with the same formula of AgC9H8N3—one is double-decked and the other single zigzag—coexist in 1:1 ratio in the crystal of 2. As far as we know, 2 is the first binary silver(I) complex based on an asymmetric triazole and represents a rare case of two supramolecular isomers
coexisting in the same crystal. 相似文献
55.
56.
Cao‐Yuan Niu Xian‐Fu Zheng Ling‐Ling Bai Xiao‐Ling Wu Chun‐Hong Kou 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(9):m305-m307
This study presents new coordinating modes of a Schiff base with three coordinating groups and an interesting two‐dimensional framework based on two types of constructing units. In the title compound, {[Ag(C14H10N4O)]ClO4}n, the AgI ion is coordinated by three N atoms and one O atom from three different N′‐(4‐cyanobenzylidene)isonicotinohydrazide (L) ligands, forming a primary distorted square‐planar coordination geometry. Two ligands each bridge two metal centres through one carbonitrile N atom in a monodentate mode and the hydrazide N and O atoms in a bidentate mode to form a small centrosymmetric (2+2)‐Ag2L2 ring as a principal constructing unit. The pyridyl N atoms from four ligands in four of these small rings coordinate to Ag atoms in adjacent rings to form a large hexanuclear silver grid. A two‐dimensional framework of rectangular grids is constructed from these small rings and large grids. Two perchlorate anions are located in each large grid and are bound to the grid by N—H...O hydrogen bonding. Crosslinking between the layers is achieved through long Ag...O interactions between the perchlorate anions and Ag atoms in adjacent layers. 相似文献
57.
Ai-Li Cui Guo-Xing Feng Ya-Fan Zhao Hui-Zhong Kou Hong Li Guang-Hua Zhu Ho-Soon Hwang Hee-Chang Oh Young-Jin Kwon Doo-Chul Lee 《Electrochemistry communications》2009,11(2):409-412
Electrochemical oxidation of graphite anode in deionized water at galvanostatic mode is investigated. It is found that mellitic acid and graphite oxide colloid (>20 nm) are coexisted as main products, as identified by XRD and TEM, FTIR and XPS. They can be separated successfully through several procedures. A few amounts of graphene and graphene rolls are also appeared as co-products. 相似文献
58.
对ISO/IEC17025-1999和ISO/IEC指南25-1990进行了比较,分析了ISO/IEC17025-1999的显著变化,提出了由ISO/IEC指南25-1990质量体系向ISO/IEC17025-1999质量体系过渡的措施。 相似文献
59.
In this paper, we present some variants of Cauchy's method for solving non-linear equations. Analysis of convergence shows that the methods have fourth-order convergence. Per iteration the new methods cost almost the same as Cauchy's method. Numerical results show that the methods can compete with Cauchy's method. 相似文献
60.
This paper introduces a novel niching scheme called the q-nearest neighbors replacement (q-NNR) method in the framework of the steady-state GAs (SSGAs) for solving binary multimodal optimization problems. A detailed
comparison of the main niching approaches are presented first. The niching paradigm and difference of the selection-recombination
genetic algorithms (GAs) and the recombination-replacement SSGAs are discussed. Then the q-NNR is developed by adopting special replacement policies based on the SSGAs; a Boltzmann scheme for dynamically sizing the
nearest neighbors set is designed to achieve a speed-up and control the proportion of individuals adapted to different niches.
Finally, experiments are carried out on a set of test functions characterized by deception, epistasis, symmetry and multimodality.
The results are satisfactory and illustrate the effectivity and efficiency of the proposed niching method. 相似文献