Brophy, Patrick M., authorFarmer, Delphine, advisorBernstein, Elliot R., committee memberMcNaughton, Brian, committee memberPierce, Jeffrey R., committee memberRavishankara, Akkihebbal R., committee member2016-08-182017-08-172016http://hdl.handle.net/10217/176732A historical account of the advances leading to modern high-resolution time-of-flight chemical ionization mass spectrometers (HR-TOF-CIMS) for gas-phase measurements is presented. Recent literature detailing the description of the HR-TOF-CIMS is critically evaluated and put into the context of the historical literature. The development of the HR-TOF-CIMS with reagent ion switching capabilities in the negative mode (acetate and iodide reagent ions), and a novel, low-pressure high-flow inlet with online calibration system is shown to work well in the field. Findings from the deployment of this measurement system during the 2013 Southern Oxidant and Aerosol Study are discussed. Subsequent work with voltage scanning methodologies for controlling cluster transmission is presented and applied to potential aerosol mass chamber experiments examining the oxidation of alpha-pinene. The applicability of acetate chemical ionization to the direct headspace analysis of beer samples is presented. Lastly, the future directions of acetate chemical ionization and voltage scanning are discussed in relation to numerous recent developments related to both gas-phase measurements and new particle formation.born digitaldoctoral dissertationsengCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.carboxylic acidsfield measurementsacetate CIMSmass spectrometrychemical ionizationText