Keywords: irradiating toluene, SOA, secondary organic aerosols, SALMS, single aerosol laser mass spectrometry, reaction mechanisms, smog chamber experiments, chemical compositions
Real-time measurements of chemical compositions of secondary organic aerosol and analysis of reaction mechanisms using Single Aerosol Laser Mass Spectrometer
A home-made Single Aerosol Laser Mass Spectrometer (SALMS) was utilised to provide on-line measurements of the sizes and molecular compositions of Secondary Organic Aerosols (SOAs) from irradiating toluene in the smog chamber. Results demonstrate that variations in reaction conditions make a little difference in the size and chemical composition distributions of SOAs. According to the reaction mechanisms, some aromatic ring-retaining and ring-opening products have been tentatively identified. Compounds from the H-abstraction pathways contribute more to the aromatic ring-reserved products. Those ring opening products could be produced from OH-addition pathways via two important intermediate species 6-oxo-2,4-heptadienal and 5-methyl-6-oxo-2,4-hexadienal isomers.