SummaryA method has been developed for the collection and analysis of polar and non-polar C4-C14 hydrocarbons involved in the formation of photochemical smog. Enrichment of hydrocarbons from both polluted and unpolluted areas has been achieved with three-stage traps packed with carbon adsorbents of different surface area; the use of a home-made desorption unit employing ctyofocusing then enables the determination of the compounds by HRGC-FID. Two-stage traps filled with graphitic carbon have been used prior to GC-MS identification and quantitation of compounds producing overlapping peaks.The methodology has been tested in the urban area of Rome and in a pine forest, and more than 140 different compounds identified and quantitated. Many of the constituents were found to be oxygenated, either formed by photochemical reactions or of anthropogenic origin.
Glass capillary columns either with modified internal area or coated with a layer of liquid phase exhibit a very high resolution and may be used to separate isotopic molecules. Optimum working conditions have been established in terms of peak resolution and analysis time.The following systems have been studied by operating at temperatures up to 77°K.: CH4-CD4, CH-CDe, C2H4-C2D4, CtHs-CyDg, and 0216-0218. The gas chro-
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.