Improvement of Gas Analysis by Enrichment of Trace Species.

摘要

The objective was to develop a continuous on-line method for enhancing the sensitivity of detection and analysis of trace components in gases. The approach was to increase the concentration of trace species in the sample flow reaching the analyzer and/or detector. Three methods were explored: (1) Inertial Enrichment in the shock layer of stagnation sampling probe on the axis of a supersonic free jet of sample gas. (2) Focusing Enrichment in which microdroplets, aerosol particles or heavy molecules comprising or containing analyte species were aerodynamically focused on the centerline of a subsonic free jet at the entrance to a sampling probe. (3) Electrospray Enrichment in which trace species were scavenged by the highly charged small droplets produced by electrospraying an appropriate liquid, then desorbed as ions for analysis by mass spectrometry. Keywords: Trace gas analysis, Aero dynamic enrichment, Particle focusing, Electrospray, Aerosols, Mass spectrometry, Inertial separation. (JS)