AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Surface Tension Measurement of Secondary Organic Aerosols Using Atomic Force Microscopy
ANDREW HRITZ, Dabrina Dutcher, Timothy Raymond, Bucknell University
Abstract Number: 261 Working Group: Instrumentation and Methods
Abstract Experimental measurements of secondary organic aerosol’s surface tension are needed to better understand these complex systems and to refine computational models that rely on our characterization of these systems. Obtaining direct measurements of surface tensions using traditional methods is challenging due to high sample volume requirements for direct measurement techniques relative to the small volumes of aerosol particles. Recent advances in Atomic Force Microscopy (AFM) tips have allowed direct measurement of the surface tension of small volumes of liquid$^1. In this study, the AFM method was utilized to directly measure the surface tension of liquid aerosols. Aerosols were generated in a small Teflon smog chamber through the oxidation of pure volatile organic compounds by ozone. The aerosols were collected by direct impaction of the liquid phase particles into custom-made impaction wells. The surface tension of the liquid aerosol from the oxidation of alpha-pinene will be presented along with a comparison of these values to values measured indirectly and those used in current models.
$^1 Yazdanpanah, Mehdi M., Mahdi Hosseini, Santosh Pabba, Scott M. Berry, Vladimir V. Dobrokhotov, Abdelilah Safir, Robert S. Keynton, and Robert W. Cohn. "Micro-wilhelmy and related liquid property measurements using constant-diameter nanoneedle-tipped atomic force microscope probes." Langmuir 24, no. 23 (2008): 13753-13764.