Microscopic analysis of aerosols collected during the CARES campaign
Authors
Alexander Laskin — Purdue University
Mary Gilles — Lawrence Berkeley National Laboratory
Ryan Moffet — Sonoma Technology Inc.
Category
Aerosol Properties
Description
STXM/NEXAFS composition map of particles collected during CARES. Of particular interest here is the mixing of soot (red) with organic (green) and inorganic material (blue).
As part of the Carbonaceous Aerosols and Radiative Effects Study (CARES), continuous sampling was performed to determine the potential effects of aerosol mixing state on optical properties. In central California, samples were collected with 20-minute resolution at fixed sites located in the urban Sacramento area (T0) and at a rural site located in the foothills of the Sierra Nevada Mountains (T1). Additional samples were collected onboard the G-1 aircraft with 3-minute time resolution. Preliminary results from scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) and scanning X-ray microscopy/near-edge X-ray absorption fine-structure spectroscopy (STXM/NEXAFS) will be presented. The SEM/EDX measurements provide insight into the elemental composition and nanostructure of thousands of individual particles. STXM/NEXAFS provides complementary information on the molecular characteristics of carbon with 35-nanometer resolution.
