Abstract
Collections of aerosol particles were carried out with an electrostatic aerosol sampler in the summertime at Nagoya and Yokkaichi which are heavily polluted areas in Japan. By electron microscopic examination 21 number size distributions of all particles and those of sulfate particles, including those in the Aitken size range, were obtained. Method for the detection of sulfate ions by electron microscopy, proposed by Bigg et al. (1974), was applied to the individual particles. Sulfate particles were found to be predominant in the range of 0.016 to 0.28λm radius and they were detected with high number fractions of particles, 55 to 75% on the average. It is considered that the distributions of aerosol particles in the Aitken size range were closely related to the behavior of sulfate particles formed by gas-to-particle conversion influenced by the amount of pre-existing particles.
