The De-activation of Ammonium Sulfate Aerosol Particles as a function of Organic Acid Deposition onto the Particle Surface: Implications for Understanding Cloud Condensation Nuclei (CCN) Activity of Processed Ambient Aerosol Particles

Authors

Erica F. Gagne, Connecticut CollegeFollow

Document Type

Article

Publication Date

May 2007

Abstract

The cloud condensation nuclei activity of organic coated ammonium sulfate particles was studied using a CCN counter in conjunction with the Aerodyne Aerosol Mass Spectrometer. The organic coatings studied were adipic acid, decanedioic acid (DEHS) and stearic acid. It was found, that the CCN activity of ammonium sulfate particles decreased as a function of insoluble (stearic, DEHS) and slightly soluble (adipic) organic coating on the surface of the aerosol particles. Due to the liquid state of DEHS, water molecules diffused through the coating and caused a slight increase in the critical supersaturation. Water was unable to diffuse through the thick and insoluble coating of stearic acid and caused the CCN activation of the ammonium sulfate core to be suppressed within the parameters of this experiment.

Recommended Citation

Gagne, Erica F., "The De-activation of Ammonium Sulfate Aerosol Particles as a function of Organic Acid Deposition onto the Particle Surface: Implications for Understanding Cloud Condensation Nuclei (CCN) Activity of Processed Ambient Aerosol Particles" (2007). Chemistry Honors Papers. 3.
https://digitalcommons.conncoll.edu/chemhp/3