Role of chemical content in water uptake processes of tropospherically relevant aerosol with diameters <100 nm

PHYS 636

Hunter B. Fontenot, hbfonten@loyno.edu and Joelle S. Underwood. Department of Chemistry, Loyola University New Orleans, 6363 St. Charles Ave., Campus Box 5, New Orleans, LA 70118
Nanoparticles of both anthropogenic and biogenic sources are ubiquitous in the atmosphere. Aerosol (liquid or solid particles suspended in air) exert a significant influence on their environment through unique chemistry and photochemistry. Aerosol are vessels for atmospheric reactions, aid in transport of nonvolatile material, play an important role as cloud condensation nuclei (CCN), and affect the earth's albedo. Both chemical content and particle diameter are critical factors that govern aerosol particle interaction with water; however, there is a lack of measurements of the hygroscopicity of model multi-component aerosol systems. Size-selected ultrafine aerosol with diameters less than 100 nm are generated in the laboratory using electrospray aerosol generation. This technique provides control over both size and chemical content of the particles. Water uptake processes are studied by measuring the growth factors of the aerosol as a function of relative humidity. Results will be presented for model oxidized and unreacted organic aerosol.
 

PHYS Poster Session - Physical Chemistry of Atmospheric Processes
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster

Sci-Mix
8:00 PM-10:00 PM, Monday, April 7, 2008 Morial Convention Center -- Hall A, Sci-Mix

Division of Physical Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008