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141.
A new way for synthesizing styrenic type of chiral resins grafting to multidentate ligand has been found. The synthetic scheme is proved to be practical by means of elemental anaysis, IR spectra and metal adsorbility. The resolving power of the new chiral ligand resins coordinated with copper (Ⅱ) as stationary phases has been discussed based on HPLC, and some points of view about the compositions of mobil phase and mechanism of resolution are presented. 相似文献
142.
Resolution of enantiomers by HPLC on cellulose derivatives 总被引:4,自引:0,他引:4
Summary Various polysaccharide derivatives, particularly cellulose derivatives, were synthesized and used as chiral stationary phases
for optical resolution by HPLC after being adsorbed on macroporous silica gel. Cellulose triacetate (CTA-II), which was synthesized
under homogeneous conditions, showed a chiral recognition ability for many racemates. Other cellulose derivatives such as
cellulose tribenzoate (OB), cellulose-trisphenylcarbamate (OC), cellulose tribenzyl ether (OE), and cellulose tricinnamate
(OK) also showed unique chiral recognition. Among other polysaccharide derivatives, curdlan triacetate was also exhibited
an effective chiral recognition.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献
143.
Summary Inverse gas chromatography is shown to be suitable for the study of the oxidation of vegetable oils. With air as carrier gas
characteristic plots of retention index versus time are obtained for hydroxylic test solutes that are consistent with the
oxidation behaviour of vegetable oils. Shifts of retention are found to be accompanied by changes of column efficiency due
to the oxidative crosslinking of polyunsaturated vegetable oils. The technique also leads to useful information concerning
the oxidation of antioxidant inhibited systems.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献
144.
Summary 2,8-Dihydroxyadeninuria and xanthinuria are inborn enzyme disorders which must be under lifelong therapeutic control. Quantitative
determination of 2,8-DHA and xanthine using reversed phase HPLC was performed. A new application for the separation of purines
shortens analysis-time. Examples of the determination of 2,8-DHA and xanthine before and under certain therapies are shown.
Long term monitoring of the patients offers the possibility of a reliable prophylaxis against stone recurrence. 相似文献
145.
146.
Summary The concept of a diffusion-averaged molecular weight, Md is presented, and Md is defined for polydisperse samples. It is shown via oligostyrene mixtures that Md can be determined in 20 minutes with common chromatographic equipment. If Md is measured and Mn or Mw is known, the polydispersity can be obtained. 相似文献
147.
建立了反相高效液相色谱法监测人口服地尔硫艹卓缓释片后血药浓度。血样用正己烷-氯仿-异丙醇混合溶剂(60405)提取后,以C18化学键合硅胶为固定相,甲醇-水-三乙胺为流动相,安定为内标,在239nm波长处定量检测。血药浓度在15~300μg/L范围内线性关系良好,最低检测浓度为3μg/L。批内(n=7)及批间(n=5)测定相对标准偏差分别小于6.8%和8.4%,回收率为91%~104%。监测了8名健康人口服盐酸地尔硫艹卓缓释片后的不同时间的血药浓度变化,计算了有关的药代动力学参数。 相似文献
148.
149.
150.
Nicolas Le Calvez 《中国化学会会志》2002,49(4):585-592
The aim of this study was to develop an analytical method to determine the organochlorine concentrations in sediments. Combination of Microwave assisted Solvent Extraction (MASE) and capillary gas chromatography with specific detection (electron capture detector) was a viable approach for the determination of pesticides in solid matrixes. In this study, MASE development was focused on the selection of a suitable extraction solvent for all the target analytes. MASE procedure was validated by comparison with conventional methods such as Soxhlet and sonication extraction. The proposed method was then applied to determine the organochlorine insecticides concentrations in samples from Authie Bay (France). Environmental water samples were analysed and five target analytes were detected in concentrations from 0.03 to 0.56 ng/g of dry sediment. These investigations showed the accumulation and the persistency of these products in sediments in spite of the fact they were banned a few decades ago. 相似文献