Humidity-dependent phase state of SOA particles from biogenic and anthropogenic precursors

Saukko E, Lambe AT, Massoli P, Koop T, Wright JP, Croasdale DR, Pedernera DA, Onasch TB, Laaksonen A, Davidovits P, Worsnop DR, et al. (2012)
ATMOSPHERIC CHEMISTRY AND PHYSICS 12(16): 7517-7529.

Download
OA 2.67 MB
Zeitschriftenaufsatz | Veröffentlicht | Englisch
Autor
; ; ; ; ; ; ; ; ; ; ;
Alle
Abstract / Bemerkung
The physical phase state (solid, semi-solid, or liquid) of secondary organic aerosol (SOA) particles has important implications for a number of atmospheric processes. We report the phase state of SOA particles spanning a wide range of oxygen to carbon ratios (O/C), used here as a surrogate for SOA oxidation level, produced in a flow tube reactor by photo-oxidation of various atmospherically relevant surrogate anthropogenic and biogenic volatile organic compounds (VOCs). The phase state of laboratory-generated SOA was determined by the particle bounce behavior after inertial impaction on a polished steel substrate. The measured bounce fraction was evaluated as a function of relative humidity and SOA oxidation level (O/C) measured by an Aerodyne high resolution time of flight aerosol mass spectrometer (HR-ToF AMS). The main findings of the study are: (1) biogenic and anthropogenic SOA particles are found to be amorphous solid or semi-solid based on the measured bounced fraction (BF), which was typically higher than 0.6 on a 0 to 1 scale. A decrease in the BF is observed for most systems after the SOA is exposed to relative humidity of at least 80% RH, corresponding to a RH at impaction of 55 %. (2) Long-chain alkanes have a low BF (indicating a "liquid-like", less viscous phase) particles at low oxidation levels (BF < 0.2 +/- 0.05 for O/C = 0.1). However, BF increases substantially upon increasing oxidation. (3) Increasing the concentration of sulphuric acid (H2SO4) in solid SOA particles (here tested for longifolene SOA) causes a decrease in BF levels. (4) In the majority of cases the bounce behavior of the various SOA systems did not show correlation with the particle O/C. Rather, the molar mass of the gas-phase VOC precursor showed a positive correlation with the resistance to the RH-induced phase change of the formed SOA particles.
Erscheinungsjahr
Zeitschriftentitel
ATMOSPHERIC CHEMISTRY AND PHYSICS
Band
12
Zeitschriftennummer
16
Seite
7517-7529
ISSN
eISSN
PUB-ID

Zitieren

Saukko E, Lambe AT, Massoli P, et al. Humidity-dependent phase state of SOA particles from biogenic and anthropogenic precursors. ATMOSPHERIC CHEMISTRY AND PHYSICS. 2012;12(16):7517-7529.
Saukko, E., Lambe, A. T., Massoli, P., Koop, T., Wright, J. P., Croasdale, D. R., Pedernera, D. A., et al. (2012). Humidity-dependent phase state of SOA particles from biogenic and anthropogenic precursors. ATMOSPHERIC CHEMISTRY AND PHYSICS, 12(16), 7517-7529. doi:10.5194/acp-12-7517-2012
Saukko, E., Lambe, A. T., Massoli, P., Koop, T., Wright, J. P., Croasdale, D. R., Pedernera, D. A., Onasch, T. B., Laaksonen, A., Davidovits, P., et al. (2012). Humidity-dependent phase state of SOA particles from biogenic and anthropogenic precursors. ATMOSPHERIC CHEMISTRY AND PHYSICS 12, 7517-7529.
Saukko, E., et al., 2012. Humidity-dependent phase state of SOA particles from biogenic and anthropogenic precursors. ATMOSPHERIC CHEMISTRY AND PHYSICS, 12(16), p 7517-7529.
E. Saukko, et al., “Humidity-dependent phase state of SOA particles from biogenic and anthropogenic precursors”, ATMOSPHERIC CHEMISTRY AND PHYSICS, vol. 12, 2012, pp. 7517-7529.
Saukko, E., Lambe, A.T., Massoli, P., Koop, T., Wright, J.P., Croasdale, D.R., Pedernera, D.A., Onasch, T.B., Laaksonen, A., Davidovits, P., Worsnop, D.R., Virtanen, A.: Humidity-dependent phase state of SOA particles from biogenic and anthropogenic precursors. ATMOSPHERIC CHEMISTRY AND PHYSICS. 12, 7517-7529 (2012).
Saukko, E., Lambe, A. T., Massoli, P., Koop, Thomas, Wright, J. P., Croasdale, D. R., Pedernera, D. A., Onasch, T. B., Laaksonen, A., Davidovits, P., Worsnop, D. R., and Virtanen, A. “Humidity-dependent phase state of SOA particles from biogenic and anthropogenic precursors”. ATMOSPHERIC CHEMISTRY AND PHYSICS 12.16 (2012): 7517-7529.
Alle Dateien verfügbar unter der/den folgenden Lizenz(en):
Copyright Statement:
This Item is protected by copyright and/or related rights. [...]
Volltext(e)
Access Level
OA Open Access
Zuletzt Hochgeladen
2017-02-03T10:12:55Z