Environmental Chamber Study of Atmospheric Chemistry and Secondary Organic Aerosol Formation Using Cavity Enhanced Absorption Spectroscopy
Air pollution and global climate change are important environmental issues that affect our society. Deeper understanding of atmospheric chemistry is required to understand these problems and to develop effective control strategies. Environmental chambers have been used for the past few decades to study atmospheric chemistry and investigate processes leading to secondary pollutant formation. This thesis work provides two different high sensitivity real time cavity enhance absorption spectroscopy (CEAS) instruments to detect NO3 radical and NO2/ glyoxal for environmental chamber study. These CEAS instruments can monitor these species with high sensitivity (in sub-ppb concentrations), with good selectivity, and with high spatial resolution in real time and in situ.
Environmental chamber studies using CEAS instruments include NO3 behavior and reaction kinetics between NO3 and amine; sources and sinks for oxides of nitrogen (NOx) in the atmospheric photooxidation reactions; glyoxal uptake by secondary organic aerosol (SOA) under dry and humid conditions and glyoxal formation from the photooxidation of aromatic and isoprene. These studies provide insightful data in atmospheric processes and lead to a better understanding of the atmospheric system, which will eventually extend to environmental policy.
This thesis is only a part of my research work. For more information about my other work, including cavity ring down spectroscopy studies for peroxy radical, aerosol optical extinction, transparent thin and time of flight mass spectrometry studies for the initial steps of ozone and alkenes reaactions, please refer to my PhD thesis in Chemistry department, UC-Riverside.