A Caltech Library Service

Studies of Ambient and Chamber Aerosol Composition Using the Aerosol Mass Spectrometer


Craven, Jill Suzanne (2013) Studies of Ambient and Chamber Aerosol Composition Using the Aerosol Mass Spectrometer. Dissertation (Ph.D.), California Institute of Technology. doi:10.7907/J69H-EK18.


This thesis presents composition measurements for atmospherically relevant inorganic and organic aerosol from laboratory and ambient measurements using the Aerodyne aerosol mass spectrometer. Studies include the oxidation of dodecane in the Caltech environmental chambers, and several aircraft- and ground-based field studies, which include the quantification of wildfire emissions off the coast of California, and Los Angeles urban emissions.

The oxidation of dodecane by OH under low NO conditions and the formation of secondary organic aerosol (SOA) was explored using a gas-phase chemical model, gas-phase CIMS measurements, and high molecular weight ion traces from particle- phase HR-TOF-AMS mass spectra. The combination of these measurements support the hypothesis that particle-phase chemistry leading to peroxyhemiacetal formation is important. Positive matrix factorization (PMF) was applied to the AMS mass spectra which revealed three factors representing a combination of gas-particle partitioning, chemical conversion in the aerosol, and wall deposition.

Airborne measurements of biomass burning emissions from a chaparral fire on the central Californian coast were carried out in November 2009. Physical and chemical changes were reported for smoke ages 0 – 4 h old. CO2 normalized ammonium, nitrate, and sulfate increased, whereas the normalized OA decreased sharply in the first 1.5 - 2 h, and then slowly increased for the remaining 2 h (net decrease in normalized OA). Comparison to wildfire samples from the Yucatan revealed that factors such as relative humidity, incident UV radiation, age of smoke, and concentration of emissions are important for wildfire evolution.

Ground-based aerosol composition is reported for Pasadena, CA during the summer of 2009. The OA component, which dominated the submicron aerosol mass, was deconvolved into hydrocarbon-like organic aerosol (HOA), semi-volatile oxidized organic aerosol (SVOOA), and low-volatility oxidized organic aerosol (LVOOA). The HOA/OA was only 0.08–0.23, indicating that most of Pasadena OA in the summer months is dominated by oxidized OA resulting from transported emissions that have undergone photochemistry and/or moisture-influenced processing, as apposed to only primary organic aerosol emissions. Airborne measurements and model predictions of aerosol composition are reported for the 2010 CalNex field campaign.

Item Type:Thesis (Dissertation (Ph.D.))
Subject Keywords:secondary organic aerosol composition
Degree Grantor:California Institute of Technology
Division:Chemistry and Chemical Engineering
Major Option:Chemical Engineering
Awards:Graduate Deans’ Award for Outstanding Community Service, 2013.
Thesis Availability:Public (worldwide access)
Research Advisor(s):
  • Seinfeld, John H. (advisor)
  • Flagan, Richard C. (co-advisor)
Thesis Committee:
  • Seinfeld, John H. (chair)
  • Flagan, Richard C.
  • Wennberg, Paul O.
  • Okumura, Mitchio
Defense Date:5 April 2013
Non-Caltech Author Email:cravenjill (AT)
Record Number:CaltechTHESIS:04112013-190107672
Persistent URL:
Related URLs:
URLURL TypeDescription 12-11795-2012DOIUNSPECIFIED 12-8439-2012DOIUNSPECIFIED
Default Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:7612
Deposited By: Jill Craven
Deposited On:22 Apr 2013 17:02
Last Modified:04 Oct 2019 00:00

Thesis Files

PDF - Final Version
See Usage Policy.


Repository Staff Only: item control page