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| Titel |
Temperature dependence of yields of secondary organic aerosols from the ozonolysis of α-pinene and limonene |
| VerfasserIn |
H. Saathoff, K.-H. Naumann, O. Möhler, A. M. Jönsson, M. Hallquist, A. Kiendler-Scharr, Th. F. Mentel, R. Tillmann, U. Schurath |
| Medientyp |
Artikel
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| Sprache |
Englisch
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| ISSN |
1680-7316
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| Digitales Dokument |
URL |
| Erschienen |
In: Atmospheric Chemistry and Physics ; 9, no. 5 ; Nr. 9, no. 5 (2009-03-03), S.1551-1577 |
| Datensatznummer |
250006999
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| Publikation (Nr.) |
 copernicus.org/acp-9-1551-2009.pdf |
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| Zusammenfassung |
| Secondary organic aerosol (SOA) formation has been investigated as a
function of temperature and humidity for the ozone-initiated reaction of the
two monoterpenes α-pinene (243–313 K) and limonene (253–313 K) using
the 84.5 m3 aerosol chamber AIDA. This paper gives an overview of the
measurements done and presents parameters specifically useful for aerosol
yield calculations. The ozonolysis reaction, selected oxidation products and
subsequent aerosol formation were followed using several analytical
techniques for both gas and condensed phase characterisation. The effective
densities of the SOA were determined by comparing mass and volume size
distributions to (1.25±0.10) g cm−3 for α-pinene and
(1.3±0.2) g cm−3 for limonene. The detailed aerosol dynamics code
COSIMA-SOA proved to be essential for a comprehensive evaluation of the
experimental results and for providing parameterisations directly applicable
within atmospheric models. The COSIMA-assisted analysis succeeded to
reproduce the observed time evolutions of SOA total mass, number and size
distributions by adjusting the following properties of two oxidation product
proxies: individual yield parameters (αi), partitioning
coefficients (Ki), vapour pressures (pi) and effective
accommodation coefficients (γi). For these properties
temperature dependences were derived and parameterised. Vapour pressures and
partitioning coefficients followed classical Clausius – Clapeyron
temperature dependences. From this relationship enthalpies of vaporisation
were derived for the two more and less volatile product proxies of α-pinene: (59±8) kJ mol−1 and (24±9) kJ mol−1, and
limonene: (55±14) kJ mol−1 and (25±12) kJ mol−1. The
more volatile proxy components had a notably low enthalpy of vaporisation
while the less volatile proxy components gave enthalpies of vaporisation
comparable with those of typical products from α-pinene oxidation,
e.g. pinonaldehyde and pinonic acid. |
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