共查询到20条相似文献,搜索用时 15 毫秒
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《液相色谱法及相关技术杂志》2012,35(5):693-726
Abstract The recent literature on aqueous gel permeation chromatography is reviewed. The chromatography of charged and uncharged solutes has been considered. A major emphasis has been to document the newer types of column packings for use in aqueous systems and their typical applications. 相似文献
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讨论了近 10年来发展较为活跃的螯合离子色谱 (CIC)的原理及其系统组成和分析流程 ,高效螯合离子色谱(HPCIC)的原理 ,高效螯合固定相的类型、应用范围及优缺点等 ,其中包括化学键合、永久涂敷或动态涂敷的高效螯合固定相 , 5 3篇。 相似文献
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《液相色谱法及相关技术杂志》2012,35(2):303-322
Abstract Countercurrent chromatography (CCC) has been successfully applied for the separation of plant hormones; namely, indole auxins, gibberellins, cytokinins and abscisic acid. In our present study three different types of CCC devices were evaluated for their performance in separation of plant hormones with a special emphasis on analysis and purification of abscisic acid (ABA). A large-scale preparative CCC apparatus consisting of a slowly rotating coil assembly was used for preliminary separations of ABA from a large volume of crude plant extracts. The toroidal coil planet centrifuge (CPC) for analytical-scale separations was subsequently applied for purification of ABA, the final confirmation being obtained by HPLC and combined gas chromatographic-mass spectrometric method. This two-step procedure utilizing preparative CCC and toroidal CPC was successfully applied for determination of ABA content in several plant tissues. A recently introduced high-speed CCC apparatus was tested for semipreparative separation of ABA and indole-3-acetic acid. The method yielded high peak resolution within 2 hours. 相似文献
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《液相色谱法及相关技术杂志》2012,35(12):2221-2238
Abstract Countercurrent chromatography (CCC) has been successfully applied for the separation of four chlorinated s-triazine derivatives, namely, simazine, atrazine, propazine, and trietazine, which are widely used as herbicides. Of several solvent systems investigated, n-hexane-ethyl acetate-methanol-water (8:2:5:5) gave the best range of the partition coefficient values because of the satisfactory solubility for all samples and therefore was used for the separation of s-triazines. Two types of countercurrent chromatographs, high speed CCC, and horizontal flow-through coil planet centrifuge, were used for s-triazines separation, and the identity of the separated fractions was unequivocally established by mass spectrometry. The potential practical application of CCC to herbicide analysis is discussed. 相似文献
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根据逆流保留方程可知,溶质的出峰顺序主要取决于其在互不混溶的两液相间分配系数的大小顺序。以饱和及不饱和脂肪酸乙酯、2,4 二硝基苯胺基脂肪醇和对硝基苯基葡萄糖甙等结构较为简单、极性差别较大的溶质系列为研究对象,应用修正的通用基团活度系数(UNIFAC)(Dortmund)模型,通过相平衡计算,预测了它们在含水或不含水的溶剂体系中分配系数的变化趋势,并与前人的工作进行了对比。结果表明,由该方法预测出的相似结构溶质分配系数的顺序基本上与实验值相同,其中对饱和脂肪酸乙酯在己烷 乙腈(体积比为1∶1)体系中分配系数的预测最好。 相似文献
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T. A. Maryutina S. N. Ignatova B. Ya. Spivakov I. A. Sutherland 《Journal of Analytical Chemistry》2003,58(8):762-767
The effect of hydrodynamic parameters and the specific features of instrument design on the efficiency of substance separation in countercurrent liquid chromatography (CCC) was studied using a constant retention factor of the stationary phase in the column. The study was conducted with the separation of benzyl alcohol and p-cresol in a two-phase liquid system heptane–ethyl acetate–methanol–water (1.4 : 0.6 : 1 : 1) in as an example. It was shown that the peak resolution is improved with an increase in the rotational speed of the column and a decrease in the flow rate of the mobile phase. The best peak separation was attained using columns for which the ratio of the column rotation radius to the radius of column revolution was 0.615. It was shown that countercurrent chromatography allows the separation of substances with low partition constants (K < 1) in dilute solutions. The volume of the test sample may be up to 15% of the total volume of the chromatography column. 相似文献
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《液相色谱法及相关技术杂志》2012,35(12):2131-2152
Abstract A novel method of performing foam separation is described. The method utilizes a gas-liquid dual countercurrent flow through a helical column subjected to a particular type of synchronous planetary motion. Samples introduced at the middle portion of the column, in either batch or continuous mode, are separated according to the foam affinity. Any material having an affinity to the foam is quickly carried with the foaming stream and eluted through one end of the column whereas other materials are carried with the liquid stream in the opposite direction and eluted out through the other end of the column. Capability of this foam countercurrent chromatographic method is demonstrated on separations of rhodamine B and Evans blue with an anionic surfactant, SDS, as a collector of rhodamine B. Successful preliminary separation of protein samples, BSA and sheep hemoglobin, indicates that the present method may be effectively applied to separation and purification of various biological samples such as enzymes, membrane receptors, etc. 相似文献
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《液相色谱法及相关技术杂志》2012,35(12):2239-2251
Abstract Countercurrent chromatography (CCC) was chosen for study as an isolation technique for pesticides and the impurities found with them, because its high capacity makes possible comparatively large batches of purified materials and because its mild operating conditions minimize the danger of degradation during the separation. Technical grade fenthion, an organophosphorus insecticide, showed traces of six impurities. The principal one found in an analytical standard fenthion was identified as 3-methyl-4-(methylthio)anisole, well separated from the fenthion. The n-octyl ester of the herbicide 2,4,5-T was easily separated from the methyl ester impurity. 相似文献
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薄层色谱在高速逆流色谱溶剂系统选择过程中的应用 总被引:9,自引:0,他引:9
本文对薄层色谱在高降流色谱的溶剂系统选择过程中的应用进行了研究,发现根据薄层色谱的斑点色度可以观察样品中各组分的含量差别及其在两相溶剂中分配系数间的差异,由此来判断溶剂系统的适用性,并确定哪一层适宜作流动相。 相似文献
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应用高速逆流色谱法对同分异构体的分离纯化进行研究。实验结果表明,以正己烷-乙酸乙酯-水(体积比为1∶10∶10)为两相溶剂系统,上相为固定相,下相为流动相,进行二次高速逆流色谱分离,可从茶多酚中分离出g级的儿茶素同分异构体——(-)-表没食子儿茶素没食子酸酯(EGCG)和(-)-没食子儿茶素没食子酸酯(GCG),其高效液相色谱纯度均在98%以上。选择四氯化碳-氯仿-甲醇-水(体积比为7∶3∶7∶3)为溶剂系统,下相为固定相,上相为流动相,经一次高速逆流色谱即可将药物中间体溴代苯胺同分异构体进行有效的分离。 相似文献