The aim of the study is to evaluate the ability of non-noble metal catalysts to function as the commercially used noble metal catalyst. The exhaust gas that was used in the project is generated from a heater developed by ReformTech AB with diesel as fuel. The compound that was focused on is carbon monoxide that has a concentration of 300-750 ppm. The catalysts that were tested are MnO/CeO2, CuO/CeO2 and a Pt/CeO2 catalyst used to compare the non-noble metal catalyst with. The sensitivity against sulfur poisoning was also analyzed by mixing sulfur into the fuel. Analysis of the exhaust gas was done with a micro-GC and the catalysts were also analyzed with SEM before and after exposure of sulfur.   The manganese catalyst with a loading of 7 wt-% did not show any activity against carbon monoxide oxidation. The copper catalysts contained two different loadings of active material, 7 and 14 wt-% and monoliths with 400 and 600 cpsi were used. Both loadings showed good activity against carbon monoxide oxidation.   The most prominent catalyst was the 14 wt-% CuO/CeO2 catalyst with a 600 cpsi monolith because of an increase in surface area. The SEM analysis showed that sulfur was present on the surface when the heater was using diesel with 300 ppm sulfur. The sulfur caused complete deactivation of the non-noble metal catalysts and a small decrease in activity was shown on the noble metal Pt catalyst.

<p>Surface mining of Alberta’s oil sands has led to significant land disturbance, making reclamation and sustainable development of this resource one of the largest challenges facing the industry today. Syncrude Canada Ltd. has developed an innovative technique to reclaim composite tailings (CT) through constructed wetland landscapes and is currently investigating the viability of a pilot-scale freshwater fen built over sandcapped CT. Unpredicted by abiotic geochemical modelling of CT behaviour, a minor episode of hydrogen sulfide (H₂S) gas release was encountered during the initial stages of fen construction indicating microbial activity was likely involved in H₂S generation within CT. This thesis investigates the S geochemistry of CT with depth and employed 454 pyrosequencing and functional enrichments to characterize the associated microbial communities in the first S biogeochemical study of oil sands CT. Porewater H₂S was detected extensively throughout the deposit with background levels ranging from 14 – 23 µM and a maximum of 301.5 µM detected at 22-24 m of depth. Reduced Fe (Fe²⁺) was also detected, but confined within surficial depths sampled, ranging from 1.2 – 38.5 µM. Mass balance calculations identify that the Fe²⁺ generated within the surficial zone of the CT deposit is sufficient to effectively sequester ambient concentrations H₂S generated in this deposit through FeS precipitates. Results identifying (1) distinct zones of porewater Fe²⁺ and H₂S, (2) co-occurrence of the highest [H₂S] and lowest dissolved organic C (DOC) at 22-24 m consistent with heterotrophic sulfate reducing bacteria (SRB) activity, and (3) the presence of mixed valence Fe biomineral, magnetite, throughout the deposit, are all consistent with microbially-mediated Fe and S cycling occurring within this CT deposit. The cultivation independent identification of several known iron reducing bacteria (IRB) and SRB within CT microbial communities, in conjunction with observed positive growth of IRB and SRB functional metabolic enrichments, demonstrates widespread capacity for microbial Fe and S activity throughout the CT deposit. Metagenomic characterization of CT microbial communities revealed high diversity (over 20 phyla) over the 5 depths examined. Multivariate statistical analyses (Unifrac) revealed that bacterial community composition and structure was driven by changed in DOC, ORP and salinity and that structuring corresponded with a surficial zone of Fe³⁺ reduction and an underlying zone of SO₄^2- reduction. Despite the high organic carbon (OC) content of oil sands tailings, much of that C is not considered to be labile and accessible to microbes. Based on the results of this thesis, CT SRB appear to have a greater ability than IRB to utilize recalcitrant OC (e.g. bitumen, naphthenic acids) given the widespread occurrence of porewater [H₂S] and surficially restricted [Fe²⁺] despite accessible pools of Fe³⁺ and OC with depth. This enhanced understanding of biogeochemical S cycling within CT newly establishes the importance of microbial activity in these processes, identifying the need to incorporate microbially based understanding into on-going development of reclamation strategies in order to manage these waste materials effectively.</p> / Master of Science (MSc)

Due to their superior thermal and chemical stability, polyimides are often used as adhesives in hazardous environments. This study examines the effect of thioether sulfur in the polyimide backbone on bond strength. X-ray photoelecton spectroscopy (XPS) and reflectance infrared spectroscopy indicated that certain metals catalyze the oxidation of the thioether sulfur. It was believed that this oxidation could lead to direct metal-oxygen-sulfur bonds across the polymer/metal interface which would serve to enhance interfacial strength. Bonds were made using substrates that were believed to catalyze the oxidation strongly (steel) and minimally (aluminum). In addition, non-sulfur containing polyimides with similar Tg were also studied for comparison. The polymer/metal interface was studied using both the T-peel and wedge tests. In some cases, oxidized sulfur was detected on the failed surfaces via XPS. No apparent effect was observed in the T-peel test, where the T-peel strengths of non-sulfur and sulfur containing polyimides were similar. In the wedge test, however, the sulfur containing BDSDA/ODA bonded to steel had an initial crack length of 34 mm. Even after eleven days the crack length was only 47 rnm, which was the initial crack length for the next best polyimide. Thus, metal-catalyzed oxidation of sulfur did take place, but not to an extent to have a noticeable effect on peel strength. / Ph. D.

This thesis makes several contributions to improve our understanding of the Neoproterozoic Paleobiology. In chapter 1, a comprehensive quantitative analysis of the Ediacara fossils indicates that the oldest Ediacara assemblage "the Avalon assemblage" already encompassed the full range of Ediacara morphospace. A comparable morphospace range was occupied by the subsequent White Sea and Nama assemblages, although it was populated differently. In contrast, taxonomic richness increased in the White Sea assemblage and declined in the Nama assemblage. The Avalon morphospace expansion mirrors the Cambrian explosion, and both may reflect similar underlying mechanisms. Chapter 2 describes problematic macrofossils collected from the Neoproterozoic slate of the upper Zhengmuguan Formation in North China and sandstone of the Zhoujieshan Formation in Chaidam. Some of these fossils were previously interpreted as animal traces. Our study of these fossils recognizes four genera and five species. None of these taxa can be interpreted as animal traces. Instead, they are problematic body fossils of unresolved phylogenetic affinities. Chapter 3 reports stable isotopes of the Zhamoketi cap dolostone atop the Tereeken diamictite in the Quruqtagh area, eastern Chinese Tianshan. Our new data indicate that carbonate associated sulfate (CAS) abundance decreases rapidly in the basal cap dolostone and δ34SCAS composition varies between +9â ° and +15â ° in the lower 2.5 m. In the overlying interval, CAS abundance remains low while δ34SCAS rises ~5â ° and varies more widely between +10â ° and +21â °. δ34Spy is typically greater than δ34SCAS measured from the same samples. We propose that CAS and pyrite were derived from two isotopically distinct reservoirs in a chemically stratified basin. Chapter 4 studies δ13C, δ18O, δ34SCAS, and δ34Spy of the Zhoujieshan cap carbonate that overlies the Ediacaran Hongtiegou glaciation. The Zhoujieshan cap dolostone shows positive δ13C values (0 â 1.7â °). δ34SCAS shows rapid stratigraphic variations from +13.9 to +24.1â °, probably due to relatively low oceanic sulfate concentrations. δ34Spy shows a steady stratigraphic trend. Thus, the δ34SCAS and δ34Spy trends are decoupled from each other. The decoupling of δ34SCAS and δ34Spy trends suggests that CAS and pyrite were derived from different sulfur pools, which were probably due to the postglacial basin stratification. / Ph. D.

AgaR, a protein in <i>Escherichia coli</i> thought to control the metabolism of N-acetylgalactosamine, is a member of the DeoR family of transcriptional regulators. Three transcriptional promoters within a cluster of genes containing the gene for AgaR were identified, specific for <i>agaR, agaZ</i> and <i>agaS</i>, and the transcription start sites mapped. Transcription from these promoters was specifically induced by N-acetylgalactosamine or galactosamine, though K-12 strains lacked the ability to utilize these as sole sources of carbon. The activity of these promoters was constitutively elevated in a strain in which <i>agaR</i> had been disrupted confirming that the promoters are subject to negative regulation by AgaR. AgaR-His6, purified using immobilized metal affinity chromatography, was used for DNase I footprint analysis of the promoter regions. Four operator sites bound by AgaR were identified. A putative consensus binding sequence for AgaR was proposed based on these four sites. <i>In vivo</i> and <i>in vitro</i> analysis of the <i>agaZ</i> promoter indicated that this promoter was activated by the cAMP-cAMP receptor protein (CRP). Expression from the <i>aga</i> promoters was less sensitive to catabolite repression in revertants capable of <i>N</i>-acetylgalactosamine utilization, suggesting that these revertants have mutation(s) that result in an elevated level of inducer for AgaR. A cluster of genes at minute 87.7 of the <i>E. coli</i> genome contains a gene that encodes another member of the DeoR family of transcriptional regulators. This protein, YihW, is more similar to GlpR, transcriptional regulator of <i>sn</i>-glycerol 3-phosphate metabolism in <i>E. coli</i>, than other members of the DeoR family. Despite the high degree of similarity, YihW lacked the ability to repress P_glpK, a promoter known to be controlled by GlpR. A variant of YihW containing substitutions in the putative recognition helix to more closely match the recognition helix of GlpR was also unable to repress P_glpK. Transcriptional promoters identified in this cluster of genes were negatively regulated by YihW. Regulation of genes involved in the metabolism of <i>sn</i>-glycerol 3-phosphate in <i>E. coli</i> by GlpR has been well characterized. However, the function of a protein (GlpE) encoded by a gene cotranscribed with that for GlpR was unknown prior to this work. GlpE was identified as a single-domain, 12-kDa rhodanese (thiosulfate:cyanide sulfurtransferase). The enzyme was purified to near homogeneity and characterized. As shown for other characterized rhodaneses, kinetic analysis revealed that catalysis occurs via an enzyme-sulfur intermediate utilizing a double-displacement mechanism requiring an active-site cysteine. K_m (SSO₃²⁻) and K_m (CN⁻) were determined to be 78 mM and 17 mM, respectively. The native molecular mass of GlpE was 22.5 kDa indicating that GlpE functions as a dimer. GlpE exhibited a kcat of 230 s-1. Thioredoxin, a small multifunctional dithiol protein, served as sulfur-acceptor substrate for GlpE with an apparent K_m of 34 mM when thiosulfate was near its K_m, suggesting thioredoxin may be a physiological substrate. / Ph. D.

Hydrogen sulfide (H2S) has been recognized as a biological signaling molecule for over twenty years now. Since these important findings emerged, many collaborative projects among chemists, biologists, and clinicians have demonstrated the physiological roles and potential therapeutic benefits of exogenous H2S delivery. As our understanding of the active roles H2S plays in biological systems has increased, so has the desire to investigate other related sulfur species (i.e. persulfides, R–SSH) for their physiological interactions with H2S and potential therapeutic efficacy. This recent interest in persulfides has stimulated a flurry of research in the field and created a new set of scientific problems to solve and opportunities to improve our understanding of persulfides in a biological context. With this surge of interest in persulfides, chemists set out to synthesize and characterize a variety of stimuli-responsive compounds that release persulfides under specific, biologically relevant conditions. In order to better understand persulfide reactivity and biological activity, and provide several prodrug platforms that respond to a variety of stimuli, this dissertation describes four persulfide-releasing prodrug systems, a pyrene-based fluorescent probe that measures H2S release in the presence of thiols, and efforts toward a peptide-based system for the release of H2S from a peptide thioacid (C(O)SH). The first four systems described utilize the well-known 1,6-benzyl elimination reaction (sometimes called self-immolation) to trigger release of a persulfide from a small molecule, polymeric, or peptide-based prodrug platform. Importantly, the first self-immolative small molecule persulfide prodrug (termed BDP-NAC) was designed to respond to reactive oxygen species (ROS). Specifically, BDP-NAC utilized a para-positioned boronic acid pinacol ester functionality to selectively react with H2O2, yielding N-acetylcysteine persulfide (NAC-SSH) and p-hydroxybenzyl alcohol as a byproduct. BDP-NAC showed trigger specificity towards H2O2, as determined by the use of a structurally analogous fluorescent probe (termed BDP-fluor). The prodrug also exhibited antioxidant properties in vitro, and served as the first example in the literature of a self-immolative persulfide donor. The second group of donors, self-immolative small molecule and peptide-based persulfide prodrugs (termed SOPD-Pep and SOPD-NAC), were designed to be responsive to superoxide (O2∙–), the primary precursor to all other ROS. In this work, the advantages of attaching small molecule persulfide donors to peptides were explored. In vitro experiments showed that SOPD-Pep mitigated toxicity induced by phorbol 12-myristate 13-acetate (PMA) more effectively than its small molecule counterpart SOPD-NAC and several common H2S donors. It is proposed that peptide scaffolds offer increased cellular uptake due to their nanoscale size, allowing for better antioxidant activity, as confirmed by fluorescence microscopy. The third section of this dissertation compares an esterase-responsive small molecule to an analogous polymeric persulfide releasing prodrug (termed EDP-NAC and polyEDP-NAC) and their abilities to decrease oxidative stress in response to immediate (H2O2) and sustained (5-fluorouracil, 5-FU) forms of ROS. Persulfide release half-lives were characterized using 1H NMR spectroscopy and showed over one order of magnitude difference between EDP-NAC and polyEDP-NAC. In vitro evaluation of the donors showed polyEDP-NAC was better suited to combat sustained production of ROS induced by 5-FU, whereas EDP-NAC was better suited to combat immediately available ROS from H2O2. These discrepancies in antioxidant activity between the two donors were deemed to be a result of their different persulfide release half-lives, indicating that scientists must take these factors into consideration when designing R–SSH prodrugs for specific disease indications. The fourth donor, NDP-NAC, responded to the bacteria-specific enzyme nitroreductase to release its persulfide payload. NDP-NAC elicited gastroprotective effects in mice that were not observed in animals treated with control compounds incapable of persulfide release or in animals treated with Na2S. NDP-NAC induced these effects by the upregulation of beneficial small and medium chain fatty acids and through increasing growth of Turicibacter sanguinis, a beneficial gut bacterium. It also decreased the populations of Synergistales bacteria, opportunistic pathogens implicated in gastrointestinal infections. Lastly, two appendices are provided in this dissertation that briefly describe the synthesis of a pyrene-based H2S sensor and efforts toward a readily accessible peptide-based thioacids as H2S donors. / Doctor of Philosophy / Hydrogen sulfide (H2S), produced naturally in hydrothermal vents and as a byproduct of industrial processes, has historically been known for its potent smell and toxicity. However, the recent discovery of H2S as a naturally-produced signaling molecule (termed gasotransmitter) in mammals has changed the way scientists view this malodorous gas. Our understanding of the biological roles and production of H2S is still growing, and recent research has suggested various links between changes in H2S concentrations in the body and a variety of disease states, including Alzheimer's, cardiovascular disease, and inflammation. Because of this link between various diseases and alterations in natural H2S production, collaborative efforts among chemists, biologists, and pharmacologists have demonstrated the usefulness of therapeutics that contain H2S-donating moieties, in an effort to alleviate these disease conditions. Persulfides (R-SSH), biological signaling molecules related to H2S, have emerged as critical species in sulfur signaling because of the similar observed antioxidative effects compared to H2S. This dissertation focuses on the synthesis and characterization of several compounds that release persulfides in response to specific stimuli (called persulfide donors). The first donor system described here releases persulfides in response to hydrogen peroxide (H2O2), a major cellular oxidant, and reduces oxidative stress in response to H2O2. The second donor system responds to superoxide (O2∙–), a precursor oxidant to H2O2 in cells, to release persulfides. Specifically, two variants of these donors, a small molecule and a peptide-based donor, exhibited antioxidant activity in response to O2∙–, but to varying degrees based on differences in cellular uptake of small molecules and self-assembled peptide nanostructures. The third donor system compares persulfide release from a small molecule and polymeric scaffold, both of which release persulfides in response to esterase enzymes. A large persulfide release half-life range was observed between the two donor systems, and antioxidant activity in response to H2O2 also varied based on the source and timescale of oxidant (H2O2 versus 5-fluorouracil). The fourth section of this dissertation focuses on a persulfide donor that responds to the bacterial enzyme nitroreductase. This donor increased levels of beneficial bacteria and short and medium chain fatty acids in murine models, while simultaneously decreasing levels of a niche subset of harmful bacteria. Taken together, these persulfide donor systems exhibit the strong reducing ability of persulfides in a biological context, showcasing the potential for therapeutic efficacy and avenues for more advanced donors to be synthesized in the future.

Soybean cultivars (Glycine max (L.) Merr.), "Dare", "Williams" and "Essex", with differential sensitivity to ozone (O₃) based on visible injury were exposed once to 0.20 µl⁻¹ O₃ and/or 0.70 µl 1⁻¹ sulfur dioxide (SO₂) for 4 hr. The cv Dare was considered sensitive, cv Williams intermediate and cv Essex tolerant to O₃. Cultivars exposed to filtered air served as controls. Gas exchange measurements were conducted and antioxidant metabolites (reduced and oxidized glutathione: GSH, GSSG; reduced and oxidized ascorbate: AA, dHAA) concentrations and enzymes (glutathione reductase: GRase; ascorbate peroxidase: APase; superoxide dismutase: SOD) activities were analyzed. Gas exchange rates of all cultivars were significantly inhibited by pollutants exposure. The cv Essex maintained significantly higher net photosynthesis (Pn) at the end of 03 exposure, during the SO₂ exposure and in the first 2 hr of O₃/SO₂ fumigation. During O₃/SO₂ exposure, the estimated pollutant fluxes were 50% and integrated doses were 25-30% of O₃ or SO₂ when fumigated singly. During O₃ fumigation, cv Dare exhibited a higher O₃ flux and integrated O₃ dose. However, cv Essex showed a higher O₃/SO₂ peak flux in O₃/SO₂ fumigation. The cv Williams showed the lowest pollutant flux in all treatments. Ozone fumigation imposed a substantial, but statistically insignificant, effect on some antioxidant components. Relative to the controls, O₃ exposure resulted in increases of GRase and SOD activity in cv Dare. In cv Williams, decreases of GSSG and SOD total activity and increase of dHAA were observed. Decreases of AA and SOD activity and increases of GSSG, dHAA and APase activity in cv Essex were found. The SO₂ exposure resulted in increases of glutathione, particularly GSSG, in all cultivars. The cv Dare responded with increases in AA, APase specific activity and SOD activity. In cv Williams, AA and SOD specific: activity increased and APase activity decreased. Decline of SOD activity in cv Essex was found after SO₂ exposure. The O₃/SO₂ fumigation resulted in increases of glutathione, particularly GSSG, and GRase activity, in all cultivars. Declines of dHAA and SOD activity in cv Williams were found. The cv Essex responded with a decline of AA and increases of dHAA and specific activity of APase and SOD. Ozone and SO₂, singly or in combination, inhibited gas exchange rates in all cultivars, however, cv Essex was the least affected. Stomatal conductance was inhibited greater by O₃ than by SO₂ fumigation. Conversely, Pn was suppressed more by SO₂ than by O₃. The O₃/SO₂ fumigation, however, suppressed Pn and Cs substantially and to a greater extent than individual pollutants. Under the pollutant dose and fumigation profile used in these studies, no consistent responses of different antioxidant components to O₃ and/or SO₂ correlated with differential sensitivity of these soybean cultivars as determined from foliar symptomology. / Ph. D.

The purpose of this study was to investigate the synthesis and properties of oxyaluminum pillared montmorillonites prepared using the controlled hydrolysis of aluminum isopropoxide as the source of pillaring species and to evaluate pillared montmorillonites as supports for hydrodesulfurization (HDS) catalysts. Several synthesis schemes were evaluated for the preparation of pillared montmorillonites. Successful pillaring was accomplished by addition of cyclohexane solutions of aluminum isopropoxide to aqueous montmorillonite suspensions. The pillared montmorillonite preparation was optimized for maximum interlayer spacing by variation of experimental parameters. Samples were characterized by x-ray diffraction and BET surface area. After dehydration a maximum interlayer spacing of approximately 6 A was obtained. As the ratio of aluminum isopropoxide to clay increased the surface area decreased. The interlayer limit was attributed to the primary pillaring species being a plate-like oxyaluminumcation having a boehmite layer structure whose thickness was about 6.1 A. Decreasing surface area for increasing aluminum to clay ratio probably resulted from exchange of larger cationic oxyaluminum plates into the interiayer volume. It was suggested that at the limit of very low surface area with a layer separation of about 6 A, the montmorillonite-oxyaluminum material consisted of alternating montmorillonite and 'boehmitem layers. / Ph. D.

Sulfur-containing compounds such as thiamin, biotin, molybdopterin, lipoic acid, and [Fe-S] clusters are essential for life. Sulfurtransferases are present in eukaryotes, eubacteria, and archaea and are believed to play important roles in mobilizing sulfur necessary for biosynthesis of these compounds and for normal cellular functions. The rhodanese homology domain is a ubiquitous structural module containing a characteristic active site cysteine residue. Some proteins containing a rhodanese domain display thiosulfate:cyanide sulfurtransferase activity in vitro. However, the physiological functions of rhodaneses remain largely unknown. YrkF, the first rhodanese to be characterized from Bacillus subtilis, is a unique protein containing two domains, an N-terminal Ccd1 domain and a C-terminal rhodanese domain. Ccd1 (conserved cysteine domain 1) is a ubiquitous structural module characterized by a Cys-Pro-X-Pro sequence motif. Thus, YrkF contains two cysteine residues (Cys¹⁵ and Cys¹⁴⁹), one in each domain. Biochemical, genetic, and bioinformatic approaches were used in order to characterize YrkF. First, YrkF was overexpressed and assayed for rhodanese activity to show that the protein is a functional rhodanese. A variant protein, YrkF^C15A, containing a cysteine to alanine substitution in the Ccd1 domain was created to determine if the Ccd1 cysteine is essential for rhodanese activity. The variant protein was overexpressed and rhodanese assays showed that YrkF^C15A is also a functional rhodanese. Inherent structural and catalytic differences were observed when comparing YrkF and YrkF^C15A, which may reflect the importance of the Ccd1 cysteine residue to normal enzymatic function and structural stability. Initial kinetic studies identified differences in activity between YrkF and YrkF^C15A. Cross-linking experiments showed a propensity for the formation of inter- and intramolecular disulfide bonds between the two cysteine residues and indicated that Cys¹⁵ and Cys¹⁴⁹ are located near one another in the 3-dimensional structure of the protein. Analysis of the proteins by mass spectrometry suggested YrkF contains a stable persulfide sulfur, whereas YrkF^C15A showed no evidence of a stable persulfide sulfur and was prone to oxidation and other active site modifications. A homology model of YrkF was created using structures of a rhodanese homolog and a Ccd1 homolog as templates. The model was used to predict the structure of YrkF based on the results of the cross-linking experiments. A strain containing a yrkF chromosomal deletion could be constructed, indicating YrkF is not essential for survival. Phenotypic analysis of the yrkF mutant revealed that YrkF is not needed for biosynthesis of sulfur-containing cofactors (thiamin, biotin, molybdopterin, or lipoic acid) or amino acids. The characterization of YrkF could lead to the discovery of novel physiological roles for rhodaneses and may give insight into possible roles for the Ccd1 module. / Master of Science

Many of the large igneous provinces during the Phanerozoic have been temporally linked to mass extinction events. The intrusion of magma into country rock has been hypothesized to facilitate the release of carbon and sulfur bearing volatiles and has been proposed as one of mechanisms that drove these mass extinctions. In this study I examine a dike of the Central Atlantic Magmatic Province and its interaction with adjacent sedimentary rocks in the Culpeper Basin of Virginia. Sampling was done at the 0.5 m scale along transects of sedimentary lithologies perpendicular to the ~170 m wide diabase intrusion. The observed mineralogical and geochemical changes in sedimentary rocks occur in a much narrower zone from the intrusion than predicted by the applied thermal model. Carbon isotopes of organic matter within the sedimentary rocks are enriched in 13C toward the intrusion indicating the generation of thermogenic methane within the first meter from the intrusion. Additionally, geochemical and petrologic textures suggest both the addition of magmatic sulfur into the country rock, shown through the isotopic signatures of sulfide minerals with mantle compositions. The possible thermal break down of sedimentary pyrite is evidenced by highly negative isotopic composition of sulfide minerals and general lack of pyrite. I suggest that sedimentary pyrite initially reacted to pyrrhotite, which was then converted to chalcopyrite through reactions with copper in fluids derived from the magma. These reactions also allowed for the formation of magnetite, which is elevated near the dike-sedimentary contact and at the end of the transect. A simple illustrative model of a hypothesis of fluid flow along the bed is used to explain the observed isotopic signatures and mineralogical changes along the transect. This study highlights how models for volatile generation through magma-country rock interaction may have overestimated the volatile fluxes from these environments and the roles that heterogeneity of sedimentary rocks and kinetic factors may have in the variance in these fluxes. / Master of Science / The intrusion of large bodies of magma called large igneous provinces have been temporally linked to mass extinction events throughout geologic time. This intrusion of magma into country rock has been hypothesized to facilitate the release of carbon and sulfur bearing gases and has been proposed as one of mechanisms that drove these mass extinctions. In this study I examine a dike of the Central Atlantic Magmatic Province and its interaction with adjacent sedimentary rocks in the Culpeper Basin of Virginia. Sampling was done along beds of sedimentary lithologies perpendicular to the ~170 m wide igneous intrusion. Geochemical and mineral analyses found that changes in mineralogy and geochemistry were in a narrower zone than predicted by the applied thermal model. Carbon isotopes of organic matter within the sedimentary rocks are enriched in 13C toward the intrusion indicating thermogenic methane generation within the first meter from the intrusion. Additionally, geochemical and mineral textures suggest the addition of magmatic sulfur into the country rock which was shown through the isotopic signatures of sulfide minerals with mantle compositions. A simple illustrative model of a hypothesis of fluid flow along the bed is used to explain the observed isotopic signatures and mineralogical changes along the transect. This study highlights how models for volatile generation through magma-country rock interaction may have overestimated the volatile fluxes from these environments and the roles that heterogeneity of sedimentary rocks and kinetic factors may have in the variance in these fluxes.