Effect of chemical structure on optical properties of secondary organic aerosols derived from C12 alkanes.

Abstract With the development of the economy, anthropogenic emissions in the atmospheric environment increases, and air pollution has caused wide public concern. Vehicle exhaust is an important emission source in the atmosphere, and alkanes are the representative components in it. In this study, the optical properties of secondary organic aerosol (SOA) derived from several C12 alkanes (2-methylundecane, hexylcyclohexane, and cyclododecane) in the absence of NOX were determined. Absorption (imaginary part of the refractive index (RI), k) at 532 nm was negligible for all the derived SOA, and the scattering (real part of RI, n) of the SOA at 532 nm followed the order of cyclododecane SOA