Spectroscopic Observation of Acid Sulfate in Atmospheric Particulate Samples

Abstract
Infrared spectra of time- and size-classified atmospheric particulate samples collected with a inertial impactor reveal the presence of acid sulfate in the submicrometer-sized fraction. Although the degree of acidity is highly variable with time, the acidic nature of the particles is observed at all times of the day and may persist for several days in urban areas.