ISSN:0935-6304    

DOI:10.1002/jhrc.1240111102

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

年代:1988

数据来源: WILEY

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111103

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

年代:1988

数据来源: WILEY

摘要:

AbstractSamples were taken of the atmospheric particulate matter over Fairbanks Alaska in the winter of 1985, and from wood stoves burning the major wood types locally available. These samples were then analyzed for polycyclic aromatic hydrocarbon (PAH). A PAH emission profile was determined from the wood stove samples and applied to the atmospheric samples to determine the residential wood combustion contribution to the local atmospheric particulate burden. Emission profiles for coal burning and automobile emissions for PAH were also used to estimate their relative contributions.

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111104

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

年代:1988

数据来源: WILEY

摘要:

AbstractThe combination of supercritical fluid extraction, high resolution capillary supercritical fluid chromatography, and Fourier transform infrared microspectrometry is described for the separation and identification of polycyclic aromatic hydrocarbons in a coal tar pitch. The variable solvating power of the supercritical fluid was utilized to selectively fractionate the sample. The fluid extract was decompressed through a frit restrictor into the sample cavity of a cooled microvalve injector, where the analytes were deposited and concentrated for subsequent chromatographic analysis. Several of the analytes separated in the chromatograph were collected on a potassium bromide disc at a solvent elimination inter‐face for subsequent infrared analysis involving the use of an infra‐red microscope accessory. The spectra obtained show the power of this detection technique for distinguishing between isom

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111105

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

年代:1988

数据来源: WILEY

摘要:

AbstractA combined sampling and analysis technique for the determination of gas phase nicotine and 3‐ethenylpyridine, and of particulate phase nicotine in environmental tobacco smoke with capillary gas chromatography is reported. The major advantage of the technique is that all of the collected particulate phase material is analyzed by thermal desorption of the collected material rather than by analysis of only a fraction of the sample extracted from the collection medium. A Teflon filter microtube is used to collect particulate phase nicotine. This microtube is follwed by a small Tenax sorbent bed to collect gas phase nicotine and 3‐ethenylpyridine. After sampling, the Teflon filter is transferred to a clean glass tube and the tube becomes an insert for a modified packed column injector port where the material collected on the filter is heat desorbed to a cold capillary tubing trap. Gas phase nicotine and 3‐ethenylpyridine are also transferred from the Tenax to the GC column by thermal desorption from the Tenax sorbent bed. Gas phase nicotine and 3‐ethenylpyridine, and particulate phase nicotine are each determined by GC analysis of the desorbed material. Nicotine and 3‐ethenylpyridine are quantitated by the use of external standards. This technique is straightforward and can be used for semi‐real time determination of both gas and particulate phase compounds in environmental tobacco smoke. The results obtained by this technique compare well with those obtained by sampling with annular diffusi

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111106

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

年代:1988

数据来源: WILEY

摘要:

AbstractExtracolumn band broadening in multidimensional systems utilizing flow switching is clearly undesirable. In certain cases,i.e.capillary recycle gas chromatography, the success of an experiment is contingent on the minimization of pre‐ and post‐column dispersion of the peaks. Knowledge of these sources of peak distortion is necessary to optimize the experimental design. A system that extracts statistical parameters from real chromatographic peaks is discussed and used to evaluate band broadening in a capillary recycle experim

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111107

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

年代:1988

数据来源: WILEY

摘要:

AbstractThermal stability and enantioselectivity of chiral polysiloxane stationary phases for gas chromatography depend upon the composition and purity of the polymer matrix, its functional groups, the chiral selector, and the pretreatment of the inner surface of the capillary. Under proper conditions, narrow‐bore capillaries can be prepared which may be used up to 300 °C for short times. Crosslinking of the phases is achieved by heati

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111108

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

年代:1988

数据来源: WILEY

摘要:

AbstractThis work describes the analysis of a pyrolysis product of a lignite sample obtained from the Turkish Goynuk reserve. The aliphatic, aromatic and polar compounds present in the tar are separated and identified by various chromatographic techniques: Capillary gas chromatography/mass spectrometry (GC/MS), on‐line high performance microbore liquid chromatography/capillary gas chromatography (LC/GC) and capillary supercritical fluid chromatography (SFC). The suitability of each technique for this particular application is discussed, and semi‐quantitative results are presented for the major components detec

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111109

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

年代:1988

数据来源: WILEY

摘要:

AbstractThe idea of unified capillary chromatography is described. Different‐mode separations could be carried out by changing the column temperature and the pressure by using a single system. Gas chromatographic separation of aromatic hydrocarbons followed by supercritical fluid chromatographic separation of styrene oligomers was carried out in series in a single chromatographic ru

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111110

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

年代:1988

数据来源: WILEY

摘要:

AbstractThe kinetics of sample evaporation was studied for four common injection liners at various temperatures. The rates of solvent and sample evaporation were measured. The sample distribution at the split point was probed by inserting two capillary columns in one injector. Greater homogeneity at the split point corresponded to higher precision (better correlation between the sample and internal standard peak areas). Evidence of aerosol formation using inverted cup inlet liners was seen. Packed column precision was better than capillary precision in each case,i.e., using straight split liners, inverted cup liners, and cold on‐column injection. Capillary precision is best when the sample and internal standard elute close together, and may be improved by using solvents that vaporize slowl

ISSN:0935-6304    

DOI:10.1002/jhrc.1240111111

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

年代:1988

数据来源: WILEY