Sergey Nizkorodov

sergey Photochemical and Dark Ageing Processes in Organic Aerosols

About the Presenter:

Sergey Nizkorodov received his undergraduate degree in biochemistry from Novosibirsk State University, Russia, in 1993 and graduate degree in chemical physics from Basel University, Switzerland, in 1997. After doing his postdoctoral research in chemical kinetics and reaction dynamics at the University of Colorado at Boulder, and in atmospheric chemistry at the California Institute of Technology, he joined the faculty of the Department of Chemistry, University of California, Irvine, in 2002. He teaches analytical, physical and atmospheric chemistry courses, and does research on chemistry of particulate matter in the ambient atmosphere and in indoor environments using state-of-the art spectroscopic and mass-spectrometric techniques. His primary areas of expertise are molecular spectroscopy, high resolution mass spectrometry, chemical reaction dynamics, and photochemistry. He has been a research mentor to 55 graduate, undergraduate and postdoctoral students including 30 female researchers. His research, education and public outreach work were recognized by several awards including Camille Dreyfus Teacher-Scholar Award, Ascent Award, Coblentz Award, and UCI Chancellor’s Award for Excellence in Fostering Undergraduate Research.

Full Presentation:


Organic compounds make up a significant, and often dominant, fraction of the atmospheric particulate matter. Primary Organic Aerosol (POA) is emitted in the atmosphere directly by various sources, and the initial molecular make-up of POA usually reflects the specific environment it originated from. Secondary Organic Aerosol (SOA) is produced directly in the atmosphere as a result of oxidation of volatile organic compounds (VOC). One of the challenges in representing organic aerosols in climate and air pollution models is their astonishingly high degree of chemical complexity. Furthermore, the chemical composition of organic aerosols is highly dynamic and continuously changes as a result of various “ageing” processes, such as photolysis, hydrolysis, oligomerization, oxidation, and other reactions involving aerosol constituents and atmospheric gases. This presentation will discuss the recent advances and current challenges in our understanding of the effects light-induced and dark ageing reactions on the molecular level chemical composition of organic aerosols, with a strong emphasis placed on so called “brown carbon”, organic aerosol that absorbs near-UV and visible radiation and plays a rather uncertain role in climate.