共查询到19条相似文献,搜索用时 78 毫秒
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金属-有机骨架材料(Metal-organic frameworks,MOFs),因其具有较好的热稳定性、化学稳定性、可设计性等特点,广泛应用于气体吸附、物质分离、提纯、催化等领域,同时也作为模板制备各种功能材料.MOFs作为色谱分离的材料已得到了较多的研究与应用.按照被分离物质的类别,综述和总结了不同MOFs材料作为色谱固定相的分离效果,重点介绍了MOFs材料的色谱分离机理.MOFs材料的孔径、功能基团和不饱和金属位点在分离中起到重要的作用,最后对MOFs在色谱分离应用中的问题和前景进行了分析和展望. 相似文献
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本文对高效液相整体柱在药物分离分析方面的应用进行了综述.主要介绍了以烷氧基硅烷为主要原料,采用溶胶-凝胶法制备的硅胶整体柱,由于其具有微米级通孔结构和大的比表面积,他们在高效、快速分离小分子物质方面得到广泛地应用.对于聚合物整体柱,主要介绍了包括分子印迹聚合物在内的有机聚合物整体柱在药物分离、生物样品的处理等方面的应用. 相似文献
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共价-有机骨架材料在色谱及样品预处理中的应用 总被引:1,自引:0,他引:1
共价-有机骨架(COFs)材料具有比表面积大、热和化学稳定性好、结构和功能多样等优点,目前已广泛用于气体储存、催化、吸附和分离等领域。近年来,以COFs为固定相和吸附剂的色谱分离和样品预处理研究引起了人们的极大兴趣。该文综述了近年来COFs的色谱和样品预处理应用研究进展,并对这一领域进行了展望。 相似文献
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亲水作用色谱是采用极性固定相、高含量极性有机溶剂-水相缓冲液为流动相的一种分离技术,它能有效地保留反相色谱中保留弱或不保留的强极性碱性药物。本文综述了以未键合硅胶为固定相的亲水作用色谱分离碱性药物的机理、特点及其应用的最新进展。 相似文献
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The enzymatic hydrolysates of casein are so complex that there is no effective method to do quantitative analysis. The common
techniques, such as high performance chromatography and SDS-PAGE, can only carry out qualitative analysis. On the basis of
membrane separation and high performance size exclusion chromatography (HPSEC), standard peptides with different molecular
mass range were prepared, and the linear relationships between mass concentration of the standard peptides and the ultraviolet
absorption of corresponding peak areas were established. Consequently, mass concentration of the different hydrolysates at
different reaction times could be accurately calculated. The combination of chromatography and membrane separation is of great
importance to the quantitative analysis of the complex hydrolysates, which can also be applied to the other macromolecular
systems, such as carbohydrates.
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Translated from Chinese Journal of Chromatography, 2005, 23(2) (in Chinese) 相似文献
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Summary A dynamic method for the preparation of diluted standards in trace analysis by Ion Chromatography is described. The proposed system uses a diffusion cell that through a capillary tube of known dimension, continuously provides large volumes of highly diluted standard.The diffusion cell setting-up and its working conditions are described, and the advantages and difficulties of the dynamic method are pointed out. Loading the cell with concentrated standard solutions (200–10000 ppm), it was possible to produce diluted Na2SO4 standards in the 0.1–10 ppb concentration range. The cell is able to work for nearly a month before the source amount decreased by 1%.The linearity of the calibration device is good and the method is free of systematic errors. Under strictly controlled experimental condition, the diffusion cell provides primary standards because it allows to obtain concentrations only depending on its geometry. 相似文献
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J. P. Abjean 《Chromatographia》1993,36(1):359-361
Summary Planar chromatography (PC) is of interest for veterinary drug screening. An example is given of the use of a PC screening method followed by a high performance liquid chromatographic (HPLC) method for confirmation of positives. The results for 300 samples were obtained in 14 days whereas the HPLC analysis alone would have required 50 days work. The future of PC in veterinary drug residue analysis as a screening method and also as confirmatory (quantitative) method is discussed. 相似文献
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F. van Stijn M. A. T. Kerkhoff B. G. M. Vandeginste 《Journal of chromatography. A》1996,750(1-2):263-273
Various off-line methods for clean-up and sample enrichment are available for the analysis of polycyclic aromatic hydrocarbons (PAHs) in edible oils and fats. These methods consist of laborious and time consuming procedures. This study reports an on-line method using LC-LC coupling. After clean-up of the sample on a donor-acceptor complex chromatography (DACC) column the PAHs are transferred to and separated on an analytical HPLC column. Quantification is carried out with fluorescence detection. The DACC column clean-up is fast and is carried out during the HPLC run of the previous sample. Compared to the traditional methods this automated on-line method saves considerable time and significantly reduces the amount of solvent waste. The method uses common HPLC equipment and its performance has been evaluated. 相似文献
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Capillary columns offer the toxicologist several advantages over packed columns. We have presented a highly reproducible screening procedure based on the retention index system and have shown the use of capillary columns for routine quantitation. We are currently expanding the use of these columns in our laboratory and predict that they will be in routine use by most toxicologists in the near future. 相似文献
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本文通过离子色谱与柱切换技术联用实现了高浓度样品基体中的痕量阴离子检测.分别研究了不同类型基体的处理方法,使用商品化离子排斥柱和自制的聚合物色谱柱实现多种样品基体中痕量阴离子的检测.同时开发一种简化的单泵柱切换系统,利用抑制器将KOH淋洗液转化为水作为前处理柱的淋洗液,在同一个色谱系统中产生两种淋洗液,实现色谱分离与前... 相似文献
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A two-dimensional (2-D) separation system of coupling chromatography to electrophoresis was developed for profiling Escherichia coli metabolites. Capillary liquid chromatography (LC) with a monolithic silica-octadecyl silica column (500 x 0.2 mm ID) was used as the first dimension, from which the effluent fractions were further analyzed by capillary electrophoresis (CE) acting as the second dimension. Field-enhanced stacking was selectively employed as a concentration strategy to interface the two dimensions, which proved to be beneficial for the detection of metabolites. An artificial sample containing 118 standards, some of which lack chromophores or have weak UV absorbance, was used to optimize the 2-D separation system. Under the optimum conditions, 63 components in the artificial sample having absorbance at 254 nm could be well resolved and detected. The utility of the system was demonstrated by comprehensive analysis of E. coli metabolites. Comparing with the previous 2-D separation system we published in Anal. Chem. 2004, 76, 1419-1428, using a longer monolithic column in the first dimension improved the separation efficiency and offered the possibility of increasing the injection volume without compromising the separation efficiency. In the second dimension, field-enhanced stacking was used to improve the concentration sensitivity of the metabolites, and more metabolites in E. coli cell extract were detected and identified using the developed 2-D separation system. In addition, preliminary investigation for future CE-mass spectrometry coupling was also made in the study by using volatile buffers in the capillary LC and CE techniques. 相似文献
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Summary A moving column-bundle counter-current chromatographic system consisting of twelve 0.9 cm id×72.5 cm long glass columns has been used for the separation of glucose-starch and glucose-maltose mixtures. The system was packed with Spherosil XOBO75 for the glucose-starch separation and with Dowex-5OW-X4K+ for the glucose-maltose separation.Purities of up to 100% were obtained and the operating throughputs were up to 4.4 kg sugar solids/m3 resin/hr. 相似文献