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Full-Text Articles in Atmospheric Sciences

Optical And Physicochemical Properties Of Atmospherically Processed Brown Carbon Using Novel First-Principle Instrumentation, Benjamin Sumlin Jan 2021

Optical And Physicochemical Properties Of Atmospherically Processed Brown Carbon Using Novel First-Principle Instrumentation, Benjamin Sumlin

McKelvey School of Engineering Theses & Dissertations

Atmospheric processing of brown carbon (BrC) – a class of spherical, internally-mixed, light-absorbing organic aerosol – emitted from smoldering biomass combustion is an understudied phenomenon with implications for climate science, air quality models, and satellite retrieval algorithms. BrC aerosols have received significant attention as a strong contributor to atmospheric light absorption in the shorter visible wavelengths and a driver of UV photochemistry. Their complex refractive indices (m=n+ik), size distributions, and carbon oxidation states dictate their optical properties, atmospheric residence times, and chemical interactions, respectively. There is currently a gap in our understanding of these fundamental particle properties and their evolution …


Development Of Novel Instrumentation And Methods To Investigate The Composition And Phase Partitioning Of Semivolatile And Intermediately Volatile Organic Compounds In Atmospheric Organic Aerosol, Claire Fortenberry May 2020

Development Of Novel Instrumentation And Methods To Investigate The Composition And Phase Partitioning Of Semivolatile And Intermediately Volatile Organic Compounds In Atmospheric Organic Aerosol, Claire Fortenberry

McKelvey School of Engineering Theses & Dissertations

Atmospheric particulate matter (PM) is ubiquitous in both indoor and outdoor air and is generally detrimental to human health. PM composed of particles with aerodynamic diameters less than 2.5 um (PM2.5) are related to adverse health outcomes including heart disease and respiratory disease. Fundamentally, particle physical properties such as size and hygroscopicity are dictated by chemical composition, which can be highly complex, particularly for organic aerosol (OA). In both outdoor and indoor air, OA is composed substantially of intermediately volatile and semivolatile organic compounds (I/SVOCs), which exist in both gas and particle phases under typical atmospheric conditions. The distribution of …


The Role Of Multi-Charged Responses: Construction And Application Of A Tandem Differential Mobility Analyzer (Tdma), Christopher Ray Oxford Dec 2019

The Role Of Multi-Charged Responses: Construction And Application Of A Tandem Differential Mobility Analyzer (Tdma), Christopher Ray Oxford

McKelvey School of Engineering Theses & Dissertations

Atmospheric aerosols impact health outcomes, visibility, and the energy balance of the earth. The atmosphere contains a variety of compounds, and the volatility (phase change enthalpy and vapor pressure) of each compound determines its partitioning between the gas phase and the particle phase. The hygroscopicity (an aerosol’s affinity for water) of an atmospheric aerosol particle is determined by the many compounds present in the particle, and thus, the volatility impacts hygroscopicity. Changes in hygroscopicity alter the fraction of the aerosol deposited in the lungs and the fraction of the aerosol activated into cloud droplets. Thus, understanding the volatility and hygroscopicity …