Characterization of the sources and processes of ambient particulate matter with high-end mass spectrometry

Ζωγράφου, Όλγα; Zografou, Olga

dc.contributor.author	Ζωγράφου, Όλγα
dc.contributor.author	Zografou, Olga
dc.date.accessioned	2025-09-22T09:22:07Z
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/62494
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.30190
dc.rights	Αναφορά Δημιουργού - Παρόμοια Διανομή 3.0 Ελλάδα	*
dc.rights.uri	http://creativecommons.org/licenses/by-sa/3.0/gr/	*
dc.subject	Atmospheric aerosols	en
dc.subject	Aerosol-clouds interactions	en
dc.subject	VOCs	en
dc.subject	Mass spectrometry	en
dc.title	Characterization of the sources and processes of ambient particulate matter with high-end mass spectrometry	en
dc.title	Characterization of the sources and processes of ambient particulate matter with high-end mass spectrometry	en
heal.type	doctoralThesis	el
heal.classification	Atmospheric chemistry	en
heal.dateAvailable	2026-09-21T21:00:00Z
heal.language	en	el
heal.access	embargo	el
heal.recordProvider	ntua	el
heal.publicationDate	2024-10-29
heal.abstract	Particulate Matter (PM) is a key atmospheric component that can cause serious climatic impacts, while also having adverse health effects on humans. The continuous monitoring of these species is therefore significant in the effort to mitigate their effects. This thesis focuses on the chemical characterization of PM1 (particles with diameter up to 1 μm) using mass spectrometry means, the application of a source apportionment scheme to trace back the sources that PM1 originated from, and finally the evaluation of a new mass spectrometer for Volatile Organic Compounds (VOCs) measurements. The first part of this thesis is focused on applying the Positive Matrix Factorization (PMF) model on the combined organic and inorganic dataset from a Time-of-Flight Aerosol Chemical Speciation Monitor (ToF-ACSM) deployed for yearlong measurements at the suburban station of the National Centre for Scientific Research Demokritos (DEM) in Athens. This analysis is compared to the conventional organics-only PMF and proved that additional information can be gained, without sacrificing in terms of quality of solution. The second study aimed at unraveling the sources and processes of PM1 at a background high-altitude location, representative of free tropospheric aerosol in the Eastern Mediterranean region. More specifically measurements with the ToF-ACSM were conducted during the Cloud-AerosoL InteractionS in the Helmos background TropOsphere (CALISHTO) campaign at the Helmos Hellenic Atmospheric Aerosol and Climate Change station ((HAC)2). The chemical species, as well as the sources retrieved by combined organic and inorganic PMF, were studied with respect to the Planetary Boundary Layer (PBL) influence on the measurements. Moreover, aerosol-cloud interactions were studied with respect to seasonal changes in the cloud formation pathways. Air mass origin was also evaluated as to its influence on chemical composition and concentration levels observed at (HAC)2. The third study evaluates a novel charge transfer mass spectrometer, developed to perform online, real-time measurements of VOCs with enhanced resolution. The instrument was evaluated under laboratory conditions, where a calibration mixture of 12 VOCs was tested. Very low detection limits were exhibited, reaching down to 1.4 ppt for compounds, such as benzene. Both proton transfer and charge transfer from background ions were found to ionize the sampled VOCs. The full width half maximum (FWHM) of the new instrument at m/z 250 is 15000. Finally, the instrument successfully performed real-time, semi-automated measurements of 5 selected VOCs (acetone, isoprene, benzene, toluene and xylene) for a 3-month summer campaign at DEM station for field measurements.	en
heal.advisorName	Tsopelas, Fotios
heal.committeeMemberName	Eleftheriadis, Konstantinos
heal.committeeMemberName	Remountaki, Emmanouella
heal.committeeMemberName	Kavousanakis, Michalis
heal.committeeMemberName	Papayannis, Alexandros
heal.committeeMemberName	Pandis, Spyridon
heal.committeeMemberName	Nenes, Athanasios
heal.academicPublisher	Σχολή Χημικών Μηχανικών	el
heal.academicPublisherID	ntua	el
heal.fullTextAvailability	false