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A three-step development, optimization and validation strategy is described for gas chromatography (GC) fingerprints of Brazilian commercial diesel fuel. A suitable GC-flame ionization detection (FID) system was selected to assay a complex matrix such as diesel. The next step was to improve acceptable chromatographic resolution with reduced analysis time, which is recommended for routine applic...

Bennett RD and Heftmann E (1962) Thin-layer chromatography of sterols. Journal of Chromatography 9: 359. Copius-Peereboom JW and Beekes HW (1965) The analysis of mixtures of animal and vegetable fats. V. Separation of sterol acetates by thin-layer chromatography in reversed-phase systems and on silica gel G} silver nitrate layers. Journal of Chromatography 17: 99. Hung GWC and Harris AZ (1989) ...

This paper reports the results of an analytical study comparing capillary gas chromatography (GC) operated in the normal mode with 2 new GC techniques, comprehensive GC (GC x GC) and targeted (or selective) multidimensional GC, which use a longitudinally modulated cryogenic system (LMCS), recently developed in our laboratory. A high-temperature application of derivatized sterols, of interest in...

A simple and rapid microextraction procedure based on dispersive liquid-liquid microextraction (DLLME) coupled with gas chromatography-flame ionization detection (GC-FID) was developed for the extraction and analysis of 2-phenylethanol in rose water sample. In the proposed approach, carbon tetrachloride and ethanol were used as extraction and dispersive solvents, respectively. Some important pa...

possibility of very selective separations that depend on the geometry of the molecules to be separated rather than the more generalized solubility mechanisms acting in gas}liquid chromatography. It should be theoretically possible to design adsorbents for particular separations. In the branch of liquid chromatography known as afRnity chromatography, for example, it is already possible to manufa...

The ionization response of hydrocarbons In a hydrogen-atmosphere flame was compared to that of a normal flame ionization detector used in gas chromatography. Absolute response in the hydrogen-atmosphere flame lonizatlon detector (HAFID) was found to be two orders of magnitude less than that of the normal FID. This reduced response is attributed both to oxidation of hydrocarbons in the precombus...

the zinc-cadmium oxide (zno-cdo) nanocomposites with different weight percentages of cadmium oxide (cdo) nanoparticles were successfully synthesized by the sonochemical method using zinc and cadmium nitrates as precursors to probe their nano-structured surfaces for the decomposition reactions of chloroethyl phenyl sulfide (ceps) as a surrogate of sulfur mustard agent simulant. scanning electron...