HR: 16:30h
AN: A54B-03    [Abstracts]
TI: Deliquescence investigated by environmental transmission electron microscopy
AU: * Wise, M E
EM: matthew.wise@asu.edu
AF: Arizona State University, Department of Geological Sciences PSF Rm 686 Box 871404 , Tempe, AZ 85287-1404 United States
AU: Biskos, G
EM: biskos@fas.harvard.edu
AF: Harvard University, Division of Engineering and Applied Sciences Pierce Hall, 29 Oxford St. , Cambridge, MA 02138 United States
AU: Martin, S T
EM: smartin@deas.harvard.edu
AF: Harvard University, Division of Engineering and Applied Sciences Pierce Hall, 29 Oxford St. , Cambridge, MA 02138 United States
AU: Buseck, P R
EM: pbuseck@asu.edu
AF: Arizona State University, Department of Geological Sciences PSF Rm 686 Box 871404 , Tempe, AZ 85287-1404 United States
AB: Although the deliquescence relative humidities of particles such as sodium chloride or ammonium sulfate are well known when their diameters are larger than 100 nm, there have been few studies on the deliquescence of particles having diameters between 1 and 100 nm, which are abundant in the troposphere. These previous studies do, however, show different behaviors of nanoparticles as they interact with water vapor. Environmental transmission electron microscopy (ETEM) allows high resolution, in-situ observation of nanoparticles as relative humidity is cycled in an environmental cell located in the electron microscope column. In order to utilize ETEM to study deliquescence of nanoparticles, the conditions the particles experience under the electron beam need to be determined. We have used a variety of sub-micron salt particles to determine water vapor pressure and particle temperature in the environmental cell of the ETEM. With this knowledge, we plan to extend the capabilities of ETEM to study phase changes of atmospherically relevant nanoparticles.
DE: 0305 Aerosols and particles (0345, 4801)
DE: 0320 Cloud physics and chemistry
DE: 0365 Troposphere--composition and chemistry
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting