ISSN:0935-6304    

DOI:10.1002/jhrc.1240020102

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

年代:1979

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020103

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

年代:1979

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020104

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

年代:1979

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020105

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

年代:1979

数据来源: WILEY

摘要:

AbstractA detection system is described which is based on fluorescent ion‐pair formation between tertiary amine drugs and dimethoxyanthracene sulphonate. A dynamic micro‐extraction principle is then used to isolate the ion‐pairs from the excess reagent. The band broadening of this extraction detector was kept below 20% using standard auto‐analyser equipment. With the enhanced selectivity and sensitivity of this approach it was possible to analyse chloropheniramine in urine at ppb concentrations using a pre‐column clean‐up trace enri

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020106

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe discrimination of the high boiling components of a C9 to C44 alkane test mixture in a vaporizing injector (analysed with stream splitting on a capillary column) is mainly due to a selective elution of the sample out of the syringe needle. Different methods of handling the syringe needle are tested. The discrimination is quantitated and correlated with the material left in the needle. The poorest method of injection was found to retain the sample in the needle when the latter is introduced into the vaporizer. The sample should be pulled back into the barrel of the syringe and the needle allowed to warm up in the injector before the sample is transferred into it. The solvent flush technique may be preferred for components sensitive to the hot metal surface of the needle.

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020107

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe possibility of simultaneous application of an electron capture (ECD) and a flame ionization detector (FID) connected to a glass capillary column for analyzing polynuclear aromatic hydrocarbons (PNA) has been investigated. The ECD/FID ratio is determined for 46 PNA compounds. The ratios vary from 0.02 to 117 with relative standard deviations better than 20 percent determined from 10 replicate analyses. The results suggest that the method may be used for obtaining additional evidence in identifying PNA in environmental samples.Impurities and transformation products in the standard were identified by computerized glass capillary gas chromatography/mass spectrometry. Quinones and diones are responsible for the high EC‐response determined in some trace components in the standard.An application of the method is shown for PNA from particulates in urban atmosphere

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020108

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe interaction energies (X1) between the polymers polypropylene, poly(vinylidene chloride), sulphonyldiphenyl formaldehyde resin and poly(vinyl pyrrolidone) and the solvents toluene, ethylbenzene, isopropylbenzene, ortho, meta, and para‐xylene are determined by gas chromatography. As shown in earlier publications, this technique for the determination of X1, can be extended to similar systems of theoretical as well as of practical importance, although the selection of the present systems was primarly made on the fact that these systems are of industrial interest and have not so far been investigated by gas‐liquid chromatography. The studies were carried out at two temperatures and the results obtained show a decrease of X1with an increase of temperat

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020109

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

年代:1979

数据来源: WILEY

摘要:

AbstractA deactivation procedure is described based on a published method using hexamethyldisilazane in the gas phase. In addition to unusually high inertia and thermostability, the method produces truly neutral columns which allow simultaneous analysis of moderately strong free acids and bases. The silylated columns show their full potential only with on‐column injection. Preliminary experimental directions are given; more elaborate directions will become available after extended optimization wor

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020110

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

年代:1979

数据来源: WILEY

摘要:

AbstractThe paper describes the measurement and calculation of the primary statistical errors in the evaluation of TLC or HPTLC using in situ reflectance measurements. The primary errors are the errors of the sample volume spotted onto the plate, errors caused by the chromatographic process itself, the positioning error of the plate with respect to the centre of the light beam and the error in the light measurement. By scanning the same spot, the same track or the same plate under different conditions, the various errors can be determined.

ISSN:0935-6304    

DOI:10.1002/jhrc.1240020111

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

年代:1979

数据来源: WILEY