« Previous AbstractComprehensive two-dimensional gas chromatography and three-dimensional fluorometry for detection of volatile and bioactive substances in some berries    Next AbstractComparison of silica gel modified with three different functional groups with C-18 and styrene-divinylbenzene adsorbents for the analysis of selected volatile flavor compounds »

Environ Sci Technol

Title:		Modeling the multiday evolution and aging of secondary organic aerosol during MILAGRO 2006
Author(s):		Dzepina K; Cappa CD; Volkamer RM; Madronich S; DeCarlo PF; Zaveri RA; Jimenez JL;
Address:		"Cooperative Institute for Research in Environmental Sciences, University of Colorado , Boulder, Colorado, USA"
Journal Title:		Environ Sci Technol
Year:		2011
Volume:		20110322
Issue:		8
Page Number:		3496 - 3503
DOI:		10.1021/es103186f
ISSN/ISBN:		1520-5851 (Electronic) 0013-936X (Linking)
Abstract:		"In this study, we apply several recently proposed models to the evolution of secondary organic aerosols (SOA) and organic gases advected from downtown Mexico City at an altitude of approximately 3.5 km during three days of aging, in a way that is directly comparable to simulations in regional and global models. We constrain the model with and compare its results to available observations. The model SOA formed from oxidation of volatile organic compounds (V-SOA) when using a non-aging SOA parameterization cannot explain the observed SOA concentrations in aged pollution, despite the increasing importance of the low-NO(x) channel. However, when using an aging SOA parameterization, V-SOA alone is similar to the regional aircraft observations, highlighting the wide diversity in current V-SOA formulations. When the SOA formed from oxidation of semivolatile and intermediate volatility organic vapors (SI-SOA) is computed following Robinson et al. (2007) the model matches the observed SOA mass, but its O/C is approximately 2x too low. With the parameterization of Grieshop et al. (2009), the total SOA mass is approximately 2x too high, but O/C and volatility are closer to the observations. Heating or dilution cause the evaporation of a substantial fraction of the model SOA; this fraction is reduced by aging although differently for heating vs dilution. Lifting of the airmass to the free-troposphere during dry convection substantially increases SOA by condensation of semivolatile vapors; this effect is reduced by aging"
Keywords:		"Aerosols/analysis/*chemistry Air Pollutants/analysis/*chemistry Environmental Monitoring/*methods *Models, Chemical Organic Chemicals/analysis/*chemistry Phase Transition Time Volatilization;"
Notes:		"MedlineDzepina, Katja Cappa, Christopher D Volkamer, Rainer M Madronich, Sasha Decarlo, Peter F Zaveri, Rahul A Jimenez, Jose L eng Research Support, Non-U.S. Gov't 2011/03/24 Environ Sci Technol. 2011 Apr 15; 45(8):3496-503. doi: 10.1021/es103186f. Epub 2011 Mar 22"