HR: 0830h
AN: A51F-0746 [PDF]
TI: Partitioning of organic aerosol components between gas phase and particulate phase
AU: Folkers, M
EM: m.folkers@fz-juelich.de
AF: ICG-II: Troposph\"are, Forschungszentrum J\"ulich, J\"ulich, 52425
Germany
AU: * Mentel, T F
EM: t.mentel@fz-juelich.de
AF: ICG-II: Troposph\"are, Forschungszentrum J\"ulich, J\"ulich, 52425
Germany
AU: Henk, H
EM: h.henk@fz-juelich.de
AF: ICG-II: Troposph\"are, Forschungszentrum J\"ulich, J\"ulich, 52425
Germany
AU: Tillmann, R
EM: r.tillmann@fz-juelich.de
AF: ICG-II: Troposph\"are, Forschungszentrum J\"ulich, J\"ulich, 52425
Germany
AU: Wahner, A
EM: a.wahner@fz-juelich.de
AF: ICG-II: Troposph\"are, Forschungszentrum J\"ulich, J\"ulich, 52425
Germany
AU: Otjes, R P
EM: otjes@ecn.nl
AF: Energy research Centre of the Netherlands, P.O.Box 1, Petten, ZG 1755
Netherlands
AU: Blom, M J
EM: m.blom@ecn.nl
AF: Energy research Centre of the Netherlands, P.O.Box 1, Petten, ZG 1755
Netherlands
AU: Ten Brink, H M
EM: tenbrink@ecn.nl
AF: Energy research Centre of the Netherlands, P.O.Box 1, Petten, ZG 1755
Netherlands
AB:
To understand the role of organics in aerosols both the
particulate composition and the gas/vapor phase composition must
determined simultaneously. Ammonium sulfates and dicarboxylic
acids are major components of continental, tropospheric aerosols.
We performed two experiments in which we studied the partitioning
of organic aerosol components between the gas and the particulate
phase. As model systems we chose ($\rm NH_4HSO_4$\,+\, glutaric
acid) aerosol and ($\rm(NH_4)HSO_4$\, +\,methyl glyoxal) aerosol
(an oxidation product of isoprene). The experiment were performed
in the large Aerosol Chamber at the FZ-J\"ulich at room
temperature. The relative humidity was constantly increased in the
course of the experiment (40\,$\rightarrow$\,90% r.h.,
60\,$\rightarrow$\,90% r.h.).\newline
%
The particulate phase was characterized on line by SJAC/IC (Steam
Jet Aerosol Collector/ Ion Chromatography, ECN) and an AMS
(Aerosol Mass Spectrometer, Aerodyne). Simultaneously we measured
the gas phase concentration of the organic component by a rotating
wet denuder/TOC (Total Organic Carbon, ECN) and PTR-MS (Proton
Transfer MS, Ionicon) and the $\rm NH_3$/$\rm NH_4^+$
concentration with an online monitor (AMANDA, ECN). Furthermore,
the particle size distribution was measured by both an SMPS (TSI)
and an APS (TSI3321). Temperature, pressure, and relative humidity
were routinely recorded.\newline
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The experimental observations will be interpretated based on
results of thermodynamic model calculations. This model utilizes a
combination of a Pitzer type model for the inorganic components
and a UNIFAC model for the organic components.\newline
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The studies are part of the EU project CASOMIO.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0365 Troposphere--composition and chemistry
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting