Health & Environmental Research Online (HERO)


Print Feedback Export to File
3457694 
Journal Article 
The Reactive-Diffusive Length of OH and Ozone in Model Organic Aerosols 
Lee, L; Wilson, K 
2016 
Yes 
Journal of Physical Chemistry A
ISSN: 1520-5215 
120 
34 
6800-6812 
English 
A key step in the heterogeneous oxidation of atmospheric aerosols is the reaction of ozone (O3) and hydroxyl radicals (OH) at the gas-particle interface. The formation of reaction products and free radical intermediates and their spatial distribution inside the particle is a sensitive function of the length over which these oxidants diffuse prior to reaction. The reactive-diffusive length of OH and ozone at organic aerosol interfaces is determined by observing the change in the effective uptake coefficient for size-selected model aerosols comprising a reactive core and a thin nanometer-sized (0-12 nm) organic shell. The core and shell materials are selected so that they are immiscible and adopt an assumed core-shell configuration. The results indicate a reactive-diffusive length of 1.4 nm for hydroxyl (OH) radicals in squalane and 1.0 nm for ozone in squalene. Measurements for a purely diffusive system allow for an estimate for diffusion constant (1.6 × 10(-6) cm(2)/s) of ozone in squalane to be determined. The reactive-diffusive length offers a simple first order estimate of how shielding of aerosols by immiscible layers can alter estimates of oxidative lifetimes of aerosols in the atmosphere. 
OPPT
• Squalane
     Literature Search
          Human Health
               PubMed (private)
          Fate
               WOS (private)