PhD Thesis Defence Presentations - Maria Zakoura
Abstract (Περίληψη)
Atmospheric particles, also known as atmospheric aerosols, are suspended particles (liquid or solid) with diameters ranging from a few nanometers to 100 μm. Atmospheric aerosols affect the Earth’s radiant budget and hence the global climate through their direct and indirect radioactive effects, and also have a negative impact on human health. They can be classified as primary (emitted directly in the particulate phase) or secondary (formed in the atmosphere via chemical reactions involving gas-phase precursors). Atmospheric particles consist of a mixture of inorganic and organic chemical compounds, including nitrate, sulfate, ammonium, organic compounds, elemental carbon, sea salt, soil and water dust, with nitrates being one of the most important inorganic compounds of particles in polluted areas.
Acidity is an important atmospheric aerosol property that drives a series of processes related to gas-particle partitioning and heterogeneous chemistry. pH affects the nitrogen cycle through the HNO3/NO3- and NH3/NH4+ gas-particle partitioning. Adverse health outcomes have been linked to strong aerosol acidity by some studies, like respiratory diseases and lung and laryngeal cancers in humans.
Chemical transport models are tools well suited for the simulation and detailed study of atmospheric processes. Historically, chemical transport models have had major problems in reproducing the observed aerosol nitrate concentrations in both the US and Europe. Also, it is important that even though aerosol pH affects many processes, the size-dependence of the aerosol pH is not simulated in detail by chemical transport models.
This thesis uses the 3-D chemical transport model PMCAMx over US with high grid resolution and in combination with a Plume-in-Grid sub-model to improve the aerosol nitrate predictions. Also, size-resolved aerosol pH predictions over Europe during May 2008 were made for the first time and their variation with time, height, presence of dust is studied, along with their impact on inorganic nitrate.
Speakers Short CV (Σύντομο Βιογραφικό Ομιλητή)
Education:
2014: M. Sc. in Chemical Engineering, Laboratory of Biochemical Engineering and Environmental Technology, Department of Chemical Engineering, University of Patras, Diploma thesis: 'Development of high-rate anaerobic system treating olive mill wastewaters', Grade: 8.70 of 10.
2011: B. Sc. in Chemical Engineering, Department of Chemical Engineering, University of Patras, Diploma thesis: 'Study of anaerobic digestion effect on phenolic fraction of olive mill wastewaters', Grade: 8.75 of 10.
2006: Experimental Senior High School of University of Patras, GPA: 19.20/20.
Research experience:
2014-2019: Graduate Research Assistant, Laboratory of Air Quality Studies, Department of Chemical Engineering, University of Patras.
2012-2014: Graduate Research Assistant, Laboratory of Biochemical Engineering and Environmental Technology, Department of Chemical Engineering, University of Patras.
2010-2011: Undergraduate Research Assistant, Laboratory of Biochemical Engineering and Environmental Technology, Department of Chemical Engineering, University of Patras.
Teaching experience:
2012 spring: Graduate Teaching Assistant, Department of Chemical Engineering, University of Patras, 'Biology'.
2015 spring: Graduate Teaching Assistant, Department of Chemical Engineering, University of Patras, 'Mathematics IV'.
2017 spring: Graduate Teaching Assistant, Department of Chemical Engineering, University of Patras, 'Analytical Chemistry Laboratoty'.
2018 spring: Graduate Teaching Assistant, Department of Chemical Engineering, University of Patras, 'Statistics for Engineers'.
Journal publications:
Zakoura, M. and Pandis, S. N., 2018. Overprediction of aerosol nitrate by chemical transport models: The role of grid resolution, Atmos. Environ., 187, 390-400.
Zakoura, M. and Pandis, S. N., 2019. Improving fine aerosol nitrate predictions using a Plume-in-Grid modeling approach, Atmos.Environ., 215, doi:10.1016/j.atmosenv.2019.116887.
Zakoura, M., Kakavas, S., Nenes, A. and Pandis, S. N.. Size-resolved aerosol pH over Europe during summer (under preparation).
Conference presentations:
M. Zakoura and S.N. Pandis: “Overprediction of fine aerosol nitrate by chemical transport models: The role of nighttime chemistry and mixing”, 4th Workshop of Graduates and Post-Docs (WGP4) in Chemical Engineering Sciences, 2018, Patras, Greece (poster presentation).
M. Zakoura and S.N. Pandis: “Overprediction of fine aerosol nitrate by chemical transport models: The role of nighttime chemistry and mixing”, 10th International Aerosol Conference (IAC), 2018, St. Louis, Missouri, USA (poster presentation).
M. Zakoura and S.N. Pandis: “The role of grid resolution on the overprediction of aerosol nitrate by chemical transport models”, 36th American Association for Aerosol Research (AAAR) Annual Conference, 2017, Raleigh, North Carolina, USA (poster presentation).
M. Zakoura and S.N. Pandis: “Grid resolution impact on the predicted PM2.5 nitrate by a 3-D chemical transport model over the Eastern USA”, 2nd Workshop of Graduates and Post-Docs (WGP2) in Chemical Engineering Sciences, 2016, Patras, Greece (poster presentation).
M. Zakoura, A. Kopsahelis and M. Kornaros: “Study of high-rate anaerobic reactors performance for the treatment of three-phase olive mill wastewater”, 9th Pan-Hellenic Scientific Conference of Chemical Engineering, 2013, Athens , Greece (oral presentation).
M. Zakoura, A. Kopsahelis and M. Kornaros: “Assessing the performance of high-rate anaerobic reactors treating three-phase olive mill wastewater (OMW)”, 13th World Congress on Anaerobic Digestion, 2013, Santiago de Compostela, Spain (oral presentation).