摘要:

In countercurrent distribution, as in other methods of separation, a solute band broadens during the analysis. This allows the definition of theoretical plates, resolution, and peak capacities in terms of CCD parameters, namely, the number of transfers and the partition coefficients. The significance and the implication of the above quantities in evaluating CCD is discussed. When possible, comparisons with other methods of separation are made.

ISSN:0037-2366    

DOI:10.1080/00372367108055559

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A theoretical analysis is made of the relative resolving power of equilibrium-gradient separation methods, such as isoelectric focusing and density-gradient sedimentation, and the corresponding kinetic methods, such as electrophoresis and kinetic centrifugatipn. Both general and specific equations are derived for resolution and peak capacity. It is concluded that peak capacity, the most general index of over-all resolving power, is of comparable magnitude for these two different approaches.

ISSN:0037-2366    

DOI:10.1080/00372367108055560

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The hydrolytic behavior of a metal can be related to its removal by foaming. In this study the effect of pH and ionic strength on the foam separation of 0.1 mM zinc (II) was investigated using different concentrations of sodium lauryl sulfate as the collector. At low pH Zn2+ion was removed by foam fractionation while above pH 8 Zn(OH)2(s) was removed by precipitate flotation. The results demonstrate that precipitate flotation is a more efficient removal process than the foam separation of soluble metal species.

ISSN:0037-2366    

DOI:10.1080/00372367108055561

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A useful chromatographic parameter–the column characteristic, [Ggrave]–is defined and derived. It contains all of the dynamic information of interest for chromatography, yet it can be determined from a single-stage experiment. The column characteristic can be employed directly to derive the column transfer function and is related to the Murphree stage efficiency for the chromatographic column operated as a single equilibrium stage. The relationship of the column characteristic to the first normal statistical moment is derived. Application is made to a simple physical situation and results are obtained for both a distributed and a discrete description of the stationary liquid phase. The nature of the discrete approximation is discussed. This paper provides the foundation for two additional papers that explore in detail several aspects of nonequilibrium chromatography.

ISSN:0037-2366    

DOI:10.1080/00372367108055562

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The relationships among the retention time, elution curve shape, and the zeroth and first partial normal moments are evaluated under conditions in which slight, moderate, or severe lateral mass transfer control exists. The elution curve and its moments are characterized by a single dirnen-sionless group, ø, which is a measure of the rate of diffusional mass transfer into the stationary phase relative to the rate of mobile-phase convective mass transfer in the axial direction. Closed form solutions are given for a discrete description (a one-term approximation to the distributed description) of the stationary liquid phase. The dimension-less retention time is derived as a function of ø and the results compared to recently published experimental observations. The first normal moment is not invariant with respect to lateral kinetic phenomena when proper account is taken of the experimental restriction of a finite cutoff time.

ISSN:0037-2366    

DOI:10.1080/00372367108055563

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

An expression for the production rate in preparative elution chromatography, based on a simplified model, is derived, and is used to illustrate the roles played by the relevant variables.

ISSN:0037-2366    

DOI:10.1080/00372367108055564

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Batch, semicontinuous, and continuous versions of the parametric pump are analyzed in terms of an equilibrium theory of pump performance. The batch pump and pumps with feed at the enriched end are shown under certain conditions to have the capacity for complete removal of solute from one product fraction and at the same time arbitrarily large enrichment of solute in the other product fraction. Under other conditions and for all conditions for pumps with feed at the depleted end separation factors and enrichment are modest.

ISSN:0037-2366    

DOI:10.1080/00372367108055565

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

An attachment for the Linear Transport System of the Gilford 2000 recording spectrophotometer is described which allows in situ continuous scanning of protein zones subjected to isoelectric focusing in sucrose gradients. Microgram quantities of protein samples can be analyzed in a short time (1.5 to 3 hr) in a quartz microcolumn. Resolution of separated components is excellent. Application of the method to the isoelectric separation of the commercially available proteins ovalbumin, beta lactoglobulin, myoglobin, Bowman-Birk soybean protease inhibitor, and rabbit gamma globulins is reported. The method provides for scanning at different wavelengths for differentiation of colored proteins, or proteins lacking tryptophan. The described procedure offers an opportunity for the studying of the kinetics of isoelectrofocusing in sucrose gradients.

ISSN:0037-2366    

DOI:10.1080/00372367108055566

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

A systematic study of the comparative extraction behavior of some divalent metals has been carried out with the high molecular weight carboxylic acid, namely SRS-100. Benzene is used as diluent. The study includes the extraction behavior as a function of pH, effect of diluent, metal ion concentration, solvent concentration, and finally interference of the associated elements. In almost all cases nearly quantitative extraction has been achieved. The proposed method is very simple, rapid, and is applicable both at micro and macro levels. The. method is applicable to extraction of metal ions in the presence of other commonly interfering ions present at the milligram level.

ISSN:0037-2366    

DOI:10.1080/00372367108055567

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

RFvalues of EDTA complexes of some common metal ions in seven solvent systems are given. The separation of Al and Be EDTA complexes has been achieved in different ratios by paper chromatography. Paper electrophoresis is also performed in four solvent systems to study the separation of EDTA complexes of metal ions.

ISSN:0037-2366    

DOI:10.1080/00372367108055568

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor