 |
| Titel |
Towards closing the gap between hygroscopic growth and activation for secondary organic aerosol – Part 2: Theoretical approaches |
| VerfasserIn |
M. D. Petters, H. Wex, C. M. Carrico, E. Hallbauer, A. Maßling, G. R. McMeeking, L. Poulain, Z. Wu, S. M. Kreidenweis, F. Stratmann |
| Medientyp |
Artikel
|
| Sprache |
Englisch
|
| ISSN |
1680-7316
|
| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 9, no. 12 ; Nr. 9, no. 12 (2009-06-18), S.3999-4009 |
| Datensatznummer |
250007431
|
| Publikation (Nr.) |
 copernicus.org/acp-9-3999-2009.pdf |
|
|
|
|
|
| Zusammenfassung |
| We examine the hygroscopic properties of secondary organic aerosol particles
generated through the reaction of α-pinene and ozone using a
continuous flow reaction chamber. The water activity versus composition
relationship is calculated from measurements of growth factors at relative
humidities up to 99.6% and from measurements of cloud condensation nuclei
activity. The observed relationships are complex, suggesting highly
non-ideal behavior for aerosol water contents at relative humidities less
than 98%. We present two models that may explain the observed water
activity-composition relationship equally well. The first model assumes that
the aerosol is a pseudo binary mixture of infinitely water soluble compounds
and sparingly soluble compounds that gradually enter the solution as
dilution increases. The second model is used to compute the Gibbs free
energy of the aerosol-water mixture and shows that the aerosol behaves
similarly to what can be expected for single compounds that contain a
certain fraction of oxygenated and non-polar functional groups. |
| |
|
| Teil von |
|
|
|
|
|
|
|
|