자료유형  

 학위논문

Control Number  

0017164684

International Standard Book Number  

9798346877134

Dewey Decimal Classification Number  

551.5

Main Entry-Personal Name  

Ziola, Anna C.

Publication, Distribution, etc. (Imprint  

[S.l.] : University of Colorado at Boulder., 2024

Publication, Distribution, etc. (Imprint  

Ann Arbor : ProQuest Dissertations & Theses, 2024

Physical Description  

162 p.

General Note  

Source: Dissertations Abstracts International, Volume: 86-06, Section: B.

General Note  

Advisor: Ziemann, Paul.

Dissertation Note  

Thesis (Ph.D.)--University of Colorado at Boulder, 2024.

Summary, Etc.  

요약Over 1000 Tg of volatile organic compounds (VOCs) are emitted into the atmosphere every year from both biogenic (Guenther et al., 2012) and anthropogenic (Huang et al., 2023) sources, an equivalent weight of about 200,000 school buses per day. Depending on the structure of these compounds and conditions in which they exist, they can remain in the atmosphere for seconds to years. This thesis investigates the fate of selected volatile organic compounds in three types of conditions: low NOx, high NOx, and indoor environments.The first study was inspired by the significant decrease of nitrogen oxides (NOx) in the U.S. in the last few decades. This reduction has led to the oxidation of VOCs - crucial for the formation of ozone and fine particles - occurring in urban areas under conditions historically associated with remote rural locations. To gain a better understanding of VOC oxidation mechanisms, I investigated the fate of two model linear alkenes that were chosen due to the high abundance of alkenes in atmospheric emissions and the simplicity of the selected compounds. By reacting 1-pentene and 3-butenoic acid with OH radicals in an environmental chamber under low NOx conditions, monitoring the gas- and particle-phase products (and 3-butenoic acid) using real-time mass spectrometry and offline techniques, and kinetics modeling, I was able to elucidate the oxidation mechanisms of these compounds. This allowed for a better understanding of the effect of a carboxyl group on reaction branching ratios and product yields.In the second study, I investigated the OH radical-initiated oxidation of a model ether compound under high NOx conditions. Ether groups are commonly found in more functionalized volatile chemical products (VCPs) - anthropogenic sources of VOCs that come from cleaning products, personal care products, adhesives, and elsewhere (Seltzer et al., 2021). Although it is known that ether groups affect reaction kinetics, nitrate yields, and SOA yields, the mechanism and degree to which a single ether group impacts the products formed from a large ether has not been determined or quantified. Therefore, for this study I reacted dioctyl ether (a symmetric C16 compound with a central ether group) with OH radicals under high NOx conditions; identified and quantified the gas- and particle-phase products using mass spectrometry, gas chromatography, liquid chromatography, and spectrophotometric techniques; and developed a quantitative reaction mechanism to explain their formation which could be used in models.In the final chapter I investigated the fate of carboxylic acids and ozone in simulated indoor conditions. Humans spend the majority of their life indoors, yet we have limited knowledge about the chemistry that occurs in these spaces. One major process that impacts the composition of indoor air is surface chemistry. Indoor spaces can have dozens of different surfaces, each with unique properties and compositions. Here, I investigated the mechanisms by which carboxylic acids and ozone interact with various wood species and wood coatings, including lacquer and shellac. An iodide chemical ionization mass spectrometer (I-CIMS) and ozone monitor were used to measure uptake coefficients and deposition velocities in uncoated and coated tubes, an attenuated total reflectance-Fourier transform infrared spectrometer was used to measure diffusion coefficients of carboxylic acids in wood and coatings, and a multi-layer model was used to extract compound diffusion coefficients and material absorbance capacities from experiments. The results were then used to develop a conceptual model for describing the interactions of carboxylic acids wood and coatings.

Subject Added Entry-Topical Term  

Atmospheric chemistry.

Subject Added Entry-Topical Term  

Analytical chemistry.

Subject Added Entry-Topical Term  

Environmental science.

Subject Added Entry-Topical Term  

Chemistry.

Index Term-Uncontrolled  

Aerosol chemistry

Index Term-Uncontrolled  

Analytical chemistry techniques

Index Term-Uncontrolled  

Atmospheric chemical mechanisms

Index Term-Uncontrolled  

Mass spectrometry

Index Term-Uncontrolled  

Oxidation chemistry

Index Term-Uncontrolled  

Wood surface chemistry

Added Entry-Corporate Name  

University of Colorado at Boulder Chemistry

Host Item Entry  

Dissertations Abstracts International. 86-06B.

Electronic Location and Access  

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Control Number  

joongbu:654739