Title: | Characterization of vapor wall loss in laboratory chambers |
Author(s): | Loza CL; Chan AW; Galloway MM; Keutsch FN; Flagan RC; Seinfeld JH; |
Address: | "Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA" |
ISSN/ISBN: | 0013-936X (Print) 0013-936X (Linking) |
Abstract: | "Laboratory chambers used to study atmospheric chemistry and aerosol formation are subject to wall loss of vapors and particles that must be accounted for in calculating aerosol yields. While particle wall loss in chambers is relatively well-understood and routinely accounted for, that of vapor is less so. Here we address experimental measurement and modeling of vapor losses in environmental chambers. We identify two compounds that exhibit wall loss: 2,3-epoxy-1,4-butanediol (BEPOX), an analog of an important isoprene oxidation product; and glyoxal, a common volatile organic compound oxidation product. Dilution experiments show that BEPOX wall loss is irreversible on short time scales but is reversible on long time scales, and glyoxal wall loss is reversible for all time scales. BEPOX exhibits minimal uptake onto clean chamber walls under dry conditions, with increasing rates of uptake over the life of an in-use chamber. By performing periodic BEPOX wall loss experiments, it is possible to assess quantitatively the aging of chamber walls" |
Keywords: | "Aerosols/chemistry Algorithms Chemistry/*methods Environmental Monitoring/methods Glyoxal/chemistry Kinetics Light Models, Statistical Organic Chemicals/chemistry Oxygen/chemistry Time Factors Volatilization;" |
Notes: | "MedlineLoza, Christine L Chan, Arthur W H Galloway, Melissa M Keutsch, Frank N Flagan, Richard C Seinfeld, John H eng Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2010/06/10 Environ Sci Technol. 2010 Jul 1; 44(13):5074-8. doi: 10.1021/es100727v" |