Ion mobility distributions during the initial stages of new particle formation by the ozonolysis of α-pinene.
An ion mobility spectrometer (IMS) was used to study gas phase compounds during nucleation and growth of secondary organic aerosols (SOA). In this study SOA particles were generated by oxidizing α-pinene with O(3) and OH in a 6 m(3) reaction chamber. Positive ion peaks with reduced mobilities of 1.59 cm(2)(Vs)(-1) and 1.05 cm(2)(Vs)(-1) were observed 7 min after α-pinene and ozone were added to the chamber. The detected compounds can be associated with low volatility oxidation products of α-pinene, which have been suggested to participate in new particle formation. This is the first time that IMS has been applied to laboratory studies of SOA formation. IMS was found suitable for continuous online monitoring of the SOA formation process, allowing for highly sensitive detection of gas phase species that are thought to initiate new particle formation.
Aerosol Physics Laboratory, Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland. anna-kaisa.viitanen@tut.fi
Anna-Kaisa
AK
Viitanen
Erkka
E
Saukko
Annele
A
Virtanen
Pasi
P
Yli-Pirilää
James N
JN
Smith
Jorma
J
Joutsensaari
Jyrki M
JM
Mäkelä
D000336:Aerosols / Q000737:chemistry*; D000393:Air Pollutants / Q000737:chemistry*; D000081008:Bicyclic Monoterpenes; D002384:Catalysis; D008401:Gas Chromatography-Mass Spectrometry; D007477:Ions / Q000737:chemistry; D039821:Monoterpenes / Q000737:chemistry*; D010126:Ozone / Q000737:chemistry*; D010316:Particle Size
D000336:Aerosols; D000393:Air Pollutants; D000081008:Bicyclic Monoterpenes; D007477:Ions; D039821:Monoterpenes; D010126:Ozone; C005451:alpha-pinene