HR: 0800h
AN: A51B-0037    [Abstracts]
TI: Mass Spectrometric Approaches to Carbon Balance in Oxidation of Biogenic Trace Gases in a Large Aerosol Chamber
AU: Tillmann, R
EM: r.tillmann@fz-juelich.de
AF: Forschungszentrum Juelich, ICG-II: Troposphaere, Juelich, 52425 Germany
AU: * Kiendler-Scharr, A
EM: a.kiendler-scharr@fz-juelich.de
AF: Forschungszentrum Juelich, ICG-II: Troposphaere, Juelich, 52425 Germany
AU: Mentel, T F
EM: t.mentel@fz-juelich.de
AF: Forschungszentrum Juelich, ICG-II: Troposphaere, Juelich, 52425 Germany
AU: Wahner, A
EM: a.wahner@fz-juelich.de
AF: Forschungszentrum Juelich, ICG-II: Troposphaere, Juelich, 52425 Germany
AB: Mass spectroscopic methods may help to determine mass balance between gas and particulate phase with high sensitivity and good time resolution. This can be achieved even if full organic speciation is not possible. We investigated the partitioning of the ozonolysis products of monoterpenes between gas and particulate phase. The experiments were performed in the large Aerosol Chamber in Juelich. Sabinene and α-Pinene were chosen as reactants; aqueous ammonium bisulphate served as seed aerosol. The gas-phase products were measured by proton transfer mass spectrometry (PTRMS). The condensation of oxidation products onto the sulphate particles was monitored by AMS (Aerosol Mass Spectrometry). From the PTR-mass spectra the fragmentation patterns and product masses were identified by linear regression analysis and by correlation analysis, respectively. We derived the fraction of carbon per consumed monoterpene which remained in the gas phase by attributing carbon numbers to the product masses. Similar, the fraction of carbon which appeared in the particulate phase was derived from the AMS data. For the α-Pinene a total carbon recovery of 0.6 (0.35 + 0.25) could be achieved for initial mixing ratios of 50 ppb O3 and 40 ppb of α-Pinene. The experiments are part of the EC project CASOMIO.
DE: 0305 Aerosols and particles (0345, 4801, 4906)
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0365 Troposphere: composition and chemistry
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005