ISSN:0935-6304    

DOI:10.1002/jhrc.1240100402

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

年代:1987

数据来源: WILEY

摘要:

AbstractA micro high performance liquid chromatography coupled with a resonance Raman detection system is described. For highly sensitive Raman detection, aliphatic amines were derivatized with dabsyl chloride (4‐dimethylaminoazobenzene‐4′‐sulfonyl chloride). The derivatives were separated on an ODS micro column (0.5 mm i.d. × 145 mm PTFE tube). Chromatograms were obtained by measuring the intensity of Raman scattering at 1136 cm−1with the 488.0 nm line of an Arion laser. The lower detection limit was 1.5 ng and the RSD of relative peak height (n = 9) was 5.9% at 11 ng of methylamine derivative. Moreover, by stopping the flow of the micro HPLC system at the retention time of the individual derivatives, it was possible to measure their resonance Ram

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100403

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

年代:1987

数据来源: WILEY

摘要:

AbstractChemical modification of commercial high performance thin‐layer chromatography plates with various mixtures of cyano‐propyltrichlorosilane and octadecyltrichlorosilane is described. Surface coverage by different treatments is demonstrated as well as the variations in chromatographic performance. With regard to the development in aqueous media the utility of CN/ ODS plates compared to ODS plates is also sh

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100404

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

年代:1987

数据来源: WILEY

摘要:

AbstractThe influence of gaseous hydrogen chloride on the efficiency and thermal stability of a Ucon LB‐550‐X stationary phase film has been studied under various working conditions. The efficiency of capillary columns was found to be unchanged or even increased, and the upper working temperature increased by 40–50°C. Nor did the action of hydrogen chloride change the polarity of the columns s

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100405

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

年代:1987

数据来源: WILEY

摘要:

AbstractProcedures are described for the normal phase and reverse phase HPLC analysis of testosterone esters having diverse side chains: examples are given of the gram‐scale purification of these compounds using two commercial preparative liquid chromatography and an economical and efficient laboratory‐assembled preparative liquid chromatogr

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100406

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

年代:1987

数据来源: WILEY

摘要:

AbstractA mathematical method for the calculation of the dead time (tm) in HPLC was evaluated using a computer simulation approach, in which artificial perturbations were introduced to Simulated homolog retention times. The calculation was based on a modified and extended Grobler and Bálisz (GB) method. Investigated wav how the precision of the calculated tMis affected by: statistical fluctuations in retention times and which, and how many homolog retention times are used. Based on these simulations a two‐step procedure for the tMcalculation is proposed: In the first step the linearity of log tR, nvs carbon number n is checked using as many homolog retention times as possible. The slope value boof the first linear regression in the GB method is used for the selection of homolog retention times in the final tMcalculation. In the second step the optimal selection of homologs is made and the final tMcalculation is carried out. Guidelines for homolog selection are giv

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100407

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

年代:1987

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100408

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

年代:1987

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100409

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

年代:1987

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100410

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

年代:1987

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240100411

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

年代:1987

数据来源: WILEY