AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Exploring Potential Brown Carbon Chromophores with Mass Spectrometry and NMR
PAIGE AIONA, Sergey Nizkorodov, Alexander Laskin, Julia Laskin, Peng Lin, University of California, Irvine
Abstract Number: 609 Working Group: Aerosol Chemistry
Abstract Atmospheric aerosols have the ability to scatter and absorb radiation, resulting in a strong influence on climate. One particular type of organic aerosol of increasing interest is “brown carbon” (BrC), which absorbs visible and near-ultraviolet light to varying degrees. Primary BrC is emitted directly from biomass and fossil fuel burning, but it can also be formed by secondary reactions in the atmosphere. It is unknown what types of compounds are responsible for the “brown” color of secondary BrC, but it is suggested by previous studies that nitrogen organic compounds (NOC) are often associated with BrC. This study will investigate the compound(s) in a variety of model BrC samples, such as products of reactions between atmospherically relevant carbonyl compounds and isotopically labelled ammonium nitrate and sulfate. We will determine the chemical form of nitrogen in BrC using nitrogen-15 nuclear magnetic resonance (NMR) spectroscopy. In addition, we will use high resolution mass spectrometry and optical absorption spectroscopy to identify BrC compounds, and fluorescence spectroscopy to further constrain its chemical properties.