摘要:

AbstractWith the simultaneous development of blank aluminum clad flexible fused silica glass capillary tubing capable of withstanding temperatures up to 500°C, coincident with a series of special high temperature methyl polysiloxane polymers, it was possible to produce for the first time, long lived fused silica capillary columns containing thin films of thermostable stationary phases which could be maintained isothermally at 400425°C and temperature programmed to 425–440°C. The “bleed rate” here for a well conditioned column was 5 picoamperes or less. Under these circumstances, alkanes with carbon numbers in the C‐90 to C‐100 area were rapidly and efficiently eluted from these columns. By extrapolation here, one can easily detect certain compounds with boiling points in the 750°C range. Since this type of capillary column was found to possess certain favorable properties, it was thought that it will soon replace the packed column and will probably be more popular than the borosilicate capillary column for many high temperature applications. Moreover, evidence has now accumulated which leads us to further believe that the majority of analyses of “high molecular weight” compounds performed by Supercritical Fluid Chromatography (SFC), utilizing very narrow bore fused silica capillary columns at several hundred atmospheres, can be much more simply, much more rapidly, much more economically, and much more efficiently accomplished by gas chromatography utilizing this new generation of high temperature

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090702

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

年代:1986

数据来源: WILEY

摘要:

AbstractA gas chromatographic method has been developed for the identification and direct determination of alcohols and methyltert‐butyl ether (MTBE) in gasolines. The technique involves simultaneous injection of the gasoline without any sample preparation onto two fused silica capillary columns of differing polarities. The method permits simultaneous determinations of methanol, ethanol, 2‐propanol,tert‐butanol, 1‐propanol,sec‐butanol, 1‐butanol, and MTBE. By using an automatic sampler in combination with electronic pressure programming and BASIC programming, the determinations were performed automatically and reproducibly with a relatively short an

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090703

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

年代:1986

数据来源: WILEY

摘要:

AbstractData are presented to illustrate putative water effects on the retention times and peak shapes for seven sulfur‐containing compounds when determined by sub‐ambient FSOT capillary GC/FPD. The observations are consistent with explanations based upon reported “phase soaking” and “reverse solvent effect

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090704

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

年代:1986

数据来源: WILEY

摘要:

AbstractA simple and rapid high‐performance liquid chromatographic method for the determination ofR[(5,6‐Dichloro‐2,3,9,9a‐tetrahydro‐3‐oxo‐9a‐propyl‐1‐H‐fluoren‐7‐yl)oxy]acetic acid (I) in human plasma and urine is described. The method utilizes Bond‐Elut® cartridge facilitate the drug extraction. Analysis is performed on a short reversed‐phase column with a mobile phase consisting of acetonitrile and phosphate buffer and quantification is carried out by ultraviolet detection with a wave‐length set at 340 nm. The method is linear and reproducible for both plasma and urine analyses (0.25–50) μg/mL) with the detection limit of 125 ng/mL of plasma and urine. Plasma and urine concentrations of / at selected time intervals following I.V. administration o

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090705

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

年代:1986

数据来源: WILEY

摘要:

AbstractA rapid, sensitive, and reliable method for the determination of nifedipine in human plasma is described. Using a single‐step solvent extraction and capillary gas chromatography combined with electron capture detection, an assay sensitivity of 2 ng/ml is achieved routinely using 0.5 ml of plasma. Intact nifedipine is quantitated and separated from its nitroso‐ and nitropyridine‐derivatives. The suitability of the assay for pharmacokinetic studies is illust

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090706

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

年代:1986

数据来源: WILEY

摘要:

AbstractMultidimensional GC (MDGC) with macrobore WCOT and PLOT columns has shown several benefits: (1) Higher flow rates, which are used, makes possible the use of common valves as the switching device; (2) very simple system configurations are possible; (3) because the columns have relatively large capacity, the TCD can be used to measure both organic and inorganic components; (4) micropacked or open tubular columns are precolumns which provide a wide range of selectivity; (5) both precolumn and analytical columns can be operated at the same flow rate without splitting of the sample. Four rapid sample analyses: (1) Oxygenates in gasohol; (2) natural gas; (3) refinery gas; (4) hydrocarbon types in naphtha, have been developed and performed on a less complex and economical gas chromatograph.

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090707

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

年代:1986

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090708

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

年代:1986

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090709

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

年代:1986

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090710

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

年代:1986

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240090711

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

年代:1986

数据来源: WILEY