This project aims to investigate the interaction of anthropogenic (human-made) emissions and biogenic emissions from plants and trees and subsequent secondary organic aerosol (SOA) production in urban environments. This is relevant as SOA is part of particulate matter (PM), which is associated with smog events in cities, affects the climate and has negative impacts on human health.
SOA is formed in the atmosphere by complex reactions of volatile organic compounds (VOCs) of anthropogenic or biogenic origin with atmospheric oxidants (OH radicals, ozone or NOx (= NO + NO2)).
A smog chamber can simulate the production of SOA from these anthropogenic and biogenic emissions under controlled lab conditions. Here, the formation of SOA from α-pinene and isoprene (the most important biogenic SOA precursors) will be investigated in the QUT smog chamber.
The smog chamber consists of a 7m³ Teflon bag mounted to an aluminium frame with a set of UV-lights at two sides of the chamber to simulate the natural solar irradiation. You will study SOA formation from α-pinene and isoprene as they are the most abundant species emitted from biogenic sources. This will be done for different concentrations of biogenic precursors and with either ambient air or zero (i.e. clean) air as a matrix).
For each experiment the mixture in the chamber will be irradiated for 4-5 hours. During that time, a range of instruments will be used to monitor in real time physical and chemical properties of particles and gases. Some of these instruments are:
- compact Time of Flight Aerosol Mass Spectrometer (c-ToF-AMS)
- Condensation Particle Counter (CPC)
- Scanning Mobility Particle Sizer (SMPS)
- Selected Ion Flow Tube Mass Spectrometer (SIFT-MS)
- Chemical Ionisation Mass Spectrometer (CIMS).
You will work with a PhD student and supervisors to operate and monitor the instruments, as well as to prepare the chamber for each experiment.
The measurements will last for 5-6 weeks and will take place during the summer break from late November to mid January 2021.
This is an excellent opportunity to learn the operation principles of many instruments used in atmospheric sciences, as well as the basic principles of aerosol measurements, and to get involved in the data analysis.
Skills and experience
This project is suitable for a physics or chemistry student.
Contact the supervisor for more information.