Atmospheric Chemistry Program Seminar
Organic nitrogen chemistry: Recent results and future projects by Prof. Ellie Browne, ANYL faculty, CU Boulder
"Organic nitrogen is a ubiquitous atmospheric component typically accounting for between one-quarter and one- third of reactive nitrogen deposition. The chemical complexity and reactivity of organic nitrogen, however, has made it challenging to study. Consequently, little is known about the atmospheric processing of organic nitrogen and the resulting implications for biogeochemistry, air quality, and climate. Research in my group uses mass spectrometry to identify the organic nitrogen compounds present in the atmosphere and to investigate the atmospheric processing of these compounds. In this talk, I will discuss our recent work on organic nitrogen chemistry and describe new projects on aerosol measurement and chemical transport modeling."
Chemistry of Volatile Organic Compounds in the Atmosphere by Prof Joost de Gouw, ANYL faculty, CU Boulder
"Volatile organic compounds (VOCs) are released from many different natural and man-made sources to the atmosphere. VOCs are removed by different oxidants on time scales of minutes to months with oxidized VOCs, ozone and fine particles as a result. These processes affect air quality and climate and are a challenge to understand due to the large number of different VOCs that are released to the atmosphere and the analytical difficulties in measuring all of these compounds as well as their oxidation products.
In our laboratory, we make measurements of VOCs by proton-transfer-reaction time-of-flight mass spectrometry (PTR-TOF) and gas chromatography mass spectrometry (GC-MS). PTR-TOF allows measurements of many different VOCs with high time resolution and without the need for pre-separation or sample treatment. GC-MS allows higher chemical detail, but at the cost of time resolution. We also combine these methods to better understand the compounds that are detected by PTR-TOF in different environments.
Several different ongoing and future projects will be presented in this seminar. First, we recently acquired a new Vocus PTR-TOF and are characterizing and preparing this instrument for measurements of indoor air in the CU Athletic Center. This will allow quantification of VOCs released from student athletes as well as during pre-game, indoor tail-gate parties. Second, we are working on the emissions and chemistry of VOCs released from volatile chemical product (VCP) use to the atmosphere, which was recently discovered to be the dominant source of VOCs in urban air. This research will involve the development of new analytical capabilities, field measurements in Boulder and in Los Angeles, and laboratory work to better understand the chemistry of VCPs. Finally, we are working on a chamber study to better understand the formation of secondary organic aerosol from biogenic VOCs."