摘要:

AbstractThe activity of fused silica capillary tubing has been shown to vary considerably, which severely influences the reproducibility of column deactivation and inertness. Methods for producing a reproducible, high activity surface with maximum hydroxylation by various hydrothermal treatments were evaluated. Columns pretreated with 20% nitric acid at 200°C for 10 hours, deactivated with D4, coated with OV‐73, and crosslinked with azo‐tert‐butane were found to possess excellent inertness for sensitive analytes such as alcohols, amines, and alkaloid

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080702

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

年代:1985

数据来源: WILEY

摘要:

AbstractThe construction and evaluation of an interface for two‐dimensional gas chromatography is described. The interface consists of commercially available components and is attachable to available gas chromatographs without any major modifications. The interface has been constructed so as to permit “heartcutting” as well as solute band concentration. Trapping is performed in a simple cold trap of fused silica. Flow switching is accomplished by Deans switching. Factors of the over‐all chromatographic performance are e

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080703

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

年代:1985

数据来源: WILEY

摘要:

AbstractCo‐bonding ligands on the same support to produce “blended” HPLC stationary phases is most commonly carried out in the form of capped reversed‐phase materials. Non‐additive retention properties were observed over a range of trimethylsilane/dimethyloctylsilane ratios. In addition, the increase in retention per mole of bonded trimethylsilane was greatest at the highest dimethyloctylsilane

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080704

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

年代:1985

数据来源: WILEY

摘要:

AbstractA thermostated HPTLC system was assembled to test the influence of gradient chamber saturation upon resolution of polar lipids chromatographed on boric acid‐impregnated silica gel plates. Inexpensive mixtures of nonacidic (14 component peaks) and acidic (8 component peaks) lipids were prepared from soya lecithin by a simplified procedure involving DEAE‐Sephadex liquid column chromatography to monitor performance of the system using a readily available reference material. The system requiresca.5 min chamber presaturation after which the polar lipids are chromatographed in less than 30 min. Retention times (tR) as well as peak area % values of all component peaks and measured by scanning photodensitometry to demonstrate the influence of different modes of chamber saturation upon the resolution of polar lop

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080705

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

年代:1985

数据来源: WILEY

摘要:

AbstractA digital chromatogram simulator has been used to evaluate the performance of data handling systems. The simulator can synthesize chromatograms with any desired shape from a library of peaks based on real peak shapes. Once generated, the chromatograms can be reproduced exactly any number of times.The algorithms used in data handling systems have a significant effect on the results they produce. An object of this work was to examine how well the true size of a peak was reported when the peak was detected overlapping with other peaks. A series of experiments was therefore performed in which peaks were overlapped by different amounts and in different situations. The reported results from the data systems were compared with the results which would have been reported had the peaks been fully resolved. A significant difference was found between the overlap results and the fully resolved results, which did not have a linear relationship with the parameters tested.The chromatogram simulator was found to be a powerful tool in assessing the performance of the data systems. It offers a valuable means of evaluating the quality of the results produced by these systems.

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080706

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

年代:1985

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080707

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

年代:1985

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080708

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

年代:1985

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080709

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

年代:1985

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080710

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

年代:1985

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240080711

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

年代:1985

数据来源: WILEY