ISSN:0935-6304    

DOI:10.1002/jhrc.1240070302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractA terminal band length is defined here as the length of a dispersed solute band as it emerges from the chromatographic column. The number of terminal band lengths per column can be used in the same way that the number of theoretical plates per column is used to measure and compare chromatographic efficiencies, but with greater insight since the proposed unit of measure is an easily visualized, real entity. In addition, the height equivalent to a theoretical plate (HETP) can be regarded as a ratio of the terminal band lenght to sixteen times the number of equivalent terminal band lengths that could be contained in tandem in the column. This concept offers another approach to understanding the meaning of the term, HETP. The terminal band length of a series of homologues is constant and independent of retention time above a certain solute molecular size and column capacity ratio. Within those conditions the correlation between the recorded peak width and retention time during isothermal analysis occurs primarily as a result of change in solute velocity.

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThe stationary‐phase capacity concepts derived from linear capacity are discussed in connection with the needs of analytical, trace enrichment analysis and preparative chromatography and shown to be unsuited to them. A new concept based on stationary‐phase saturation and called “available capacity” is proposed. It generalizes the ion‐exchanger exchange capacity to adsorption and partition chromatography when the sampling solvent is the mobile phase.In linear elution chromatography the available capacity is proportional to the solute concentration Coand to the analytical capacity factor k′ for given Coand k′ values, it is independent of the nature of the solute. Furthermore, when both the concentrations and the analytical capacity factors (practically, for Co≥ 1 M and k′ ≥ 10, respectively) are high, the available capacity reaches a value roughly independent of Coand k′, called “maximum available capacity” and related only to the number of sites available on the stationary phase. Numerous measurements were made in ion‐exchange, adsorption, and reversed‐phase chromatography. For solutes having a single polar functional group interacting with the stationary phase, the orders of magnitude of the maximum available capacity are 1.2 mmole g−1for a classical silica gel (Partisil 5 μm, 400m−2g−1with a water content of 2.7%); 1.8 mmole g−1for the Lichroprep RP 8 octyl bonded silica (11.6% carbon content); 3.8 mmole g−1fo

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractIt is proposed to extend the area of application of circular separation of substances in flat‐bed chromatography by a wider use of its intermedial modifications. Equations for calculating the basic parameters of migration of the mobile phase and zones of separated substances are given. The known equations are shown to be particular cases of the ones propose

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240070311

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY