AAAR 33rd Annual Conference
October 20 - October 24, 2014
Rosen Shingle Creek
Orlando, Florida, USA
Abstract View
Initial Field Deployments of a Volatility and Polarity Separator (VAPS) for Organic Aerosol Characterization
RAUL MARTINEZ, David Hagan, Yaping Zhang, Dhruv Mitroo, Michael Walker, Lu Hu, Munkhbayar Baasandorj, Dylan Millet, Brent Williams, Washington University in St. Louis
Abstract Number: 408 Working Group: Air Quality and Climate in the Southeast US: Insights from Recent Measurement Campaigns
Abstract The Volatility and Polarity Separator (VAPS) was deployed during two field campaigns in the summer and fall of 2013 – Centerville, Alabama and East St. Louis, Illinois. VAPS was used to obtain hourly measurements of chemically resolved organic aerosol (OA) detected using high-resolution time-of-flight mass spectrometry (HR-ToFMS). This novel instrument increases the mass throughput of ambient OA in comparison to traditional GC by utilizing shorter transfer paths and passivated coatings. Chemical separation resolution is sacrificed for this increased mass transfer, but the high-resolution mass spectral data recovers information such as chemical classes and even some individual compounds along with elemental composition to determine aerosol oxidation states.
The ambient data sets are explored by using high resolution mass spectral analysis and positive matrix factorization (PMF). Different techniques for interpreting and representing VAPS data are considered and PMF factors are compared to meteorological and chemical data from other co-located instruments. Differences and similarities between the two sites are also presented.