Counteracting chromatographic

Locke, BR Carbonell, RG, A Theoretical and Experimental Study of Counteracting Chromatographic Electrophoresis, Separation and Purification Methods 18, 1, 1989. 

McCoy, B. J. "Counteracting chromatographic electrophoresis and related imposed-gradient sejjaration processes" AIChE J. 1986,32, pp 1570-73. 

British thermal unit continuous annular chromatograph counteracting chromatographic electrophoresis... 

Abscisin II is a plant hormone which accelerates (in interaction with other factors) the abscission of young fruit of cotton. It can accelerate leaf senescence and abscission, inhibit flowering, and induce dormancy. It has no activity as an auxin or a gibberellin but counteracts the action of these hormones. Abscisin II was isolated from the acid fraction of an acetone extract by chromatographic procedures guided by an abscission bioassay. Its structure was determined from elemental analysis, mass spectrum, and infrared, ultraviolet, and nuclear magnetic resonance spectra. Comparisons of these with relevant spectra of isophorone and sorbic acid derivatives confirmed that abscisin II is 3-methyl-5-(1-hydroxy-4-oxo-2, 6, 6-trimethyl-2-cyclohexen-l-yl)-c s, trans-2, 4-pen-tadienoic acid. This carbon skeleton is shown to be unique among the known sesquiterpenes. 

Puerariae Flos (the flowers of Pueraria lobata) is a crude drug used for counteraction to alcohol intoxication in traditional Japanese and Chinese therapeutic systems [20]. We have found that total OGs were effective for alcohol intoxication [21]. It was also effective for an experimental in vivo model of hepatic injury [22]. That is, the total OG decreased the alanine aminotransferase (ALT) level in high fatty food-induced and CCl4-induced experimental liver injury. After repeating some chromatographic technique, we obtained three OGs together with several isoflavones [20]. 

The practical value of any preparative chromatographic procedure is usually evaluated as the maximum volume of the sample that can still be tolerated by the column and the concentration of that sample. The two parameters usually counteract each other. From this viewpoint, ISE of electrolytes appears to be superior to all other chromatographic techniques in that the volume loading of a column increases with the increase in the concentration of the feed. This phenomenon results from the unique feature of the ISE technique that the phase distribution coefficients of two components fortunately change with increasing concentration smaller ions are forced to additionally concentrate in stagnant fine pores, while large ions are additionally excluded into the interstitial volume. 

As a general rule, highly acidic or highly basic samples are difficult to chromatograph because of their high reactivity and strong hydrogenbonding. To counteract these effects it has become common to add a small amount (1-2%) of modifier to the liquid phase to cover up the most active... 

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