Fig. 3.

Time-dependent particle size distributions formed by gas-phase nucleation in a chamber. (A) Obtained from the UMN chamber measurements, where SO₂ undergoes oxidation in the presence of amines (total amine = 0.9 ppbv). Size distributions shown in B were obtained by assuming that monomer is formed at the same rate as in the experiment shown in A, and that coagulation is collision controlled (i.e., monomer and clusters always stick when they collide and evaporation from clusters does not occur).