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<p> Asymmetric synthesis and catalysis is one of the leading research areas in chemistry society, for its versatility and efficiency in obtaining chiral molecules that found the vast majority in natural active compounds and synthetic drugs. Developing asymmetric catalytic methodology is at the frontier in both industrial and academic research laboratories. Enantioselective organocatalysis has emerged as a powerful synthetic tool that is complementary to metal-catalyzed transformations. The development of chiral phosphoric acid and metal phosphate as catalysts has been a breakthrough in recent years. Chiral phosphoric acids have been shown to be powerful catalysts in many organic transformations. Moreover, chiral metal phosphates, which formed by simply replacing the proton in phosphoric acid with metals, have introduced new catalytic activations and broaden the scope of phosphoric acids. This thesis details new highly enantioselective chiral phosphoric acid-catalyzed Pinacol rearrangement and robust alkaline phosphates catalytic system, which utilizes novel carbonyl activation. </p><p> The Pinacol rearrangement has long been known to be difficult to control in terms of regioselectivity and stereoselectivity. The initial studies found that indolyl-diol compounds can be treated with chiral phosphoric acids to afford the Pinacol rearrangement with high regio- and enantioselectivity. Over 16 chiral phosphoric acids were screened, and it was found an H8-BINOL-phosphoric acid variant with 1-naphthyl groups at 3 and 3' position was the excellent catalyst. This asymmetric transformation is tolerant toward variety of substituents both on the indole ring and migrating groups. </p><p> During the study, it was found that different ways to generate the catalyst had critical effect on this catalytic transformation. Only those phosphoric acids washed with HCl after column chromatography afforded the rearrangement products with high enantioselectivity. And those without treating with HCl were found contaminated by alkaline metals. These "contamination" catalysts were also found active with carbonyl activations. </p><p> A highly enantioselective catalytic hetero-Diels-Alder reaction of alpha-keto esters has been developed with chiral alkaline metal phosphates. A calcium 1-naphthyl-BINOL phosphate was found to be the optimum catalyst. A large range of alpha-keto esters as well as isatins can be applied in this alkaline phosphates catalytic system with high efficiency and selectivity. The structure of the catalyst is detailed for the first time by X-ray crystal structure analysis. A proposed Transition state model is provided based on the catalyst crystal structure and Raman spectroscopy analysis. </p><p> This methodology was further developed with an asymmetric Mukaiyama-Michael addition of beta,gamma-unsaturated alpha-keto ester. The best catalyst was found to be a magnesium chiral phosphate. And the transformation was found capable of tolerating a wide variety of beta,gamma-unsaturated alpha-keto esters.</p>

As ~ 50% of global photosynthesis occurs in marine environments, the factors regulating this process e.g. trace metal availability, have an impact on the global carbon cycle. The key cyanobacteria genera Prochlorococcus and Synechococcus have an absolute requirement for Co. Dissolved cobalt (dCo) concentrations in the open ocean are extremely low (5–120 pM). A sensitive flow injection technique using chemiluminescence detection (FI-CL) was developed (detection limit 4.5 pM dCo, RSD ≤ 4%). Seawater samples must be UV-irradiated prior to analysis, in order to liberate organically-bound Co. A field study in the Sargasso Sea, demonstrated that aerosol Co was significantly more soluble than aerosol Fe over a range of aerosol dust deposition fluxes (1–1040 μg Fe m-2 d-1) (8-100% for Co versus 0.44-45% for Fe). The dry deposition flux of aerosol Co was of the same order of magnitude as the advective upwelling flux (47-1540 pmol m-2 d-1 and 1.7-1430 pmol m-2 d-1 respectively). Wet deposition, dominated the total aerosol flux (~ 85%). The vertical distribution of dCo influenced Prochlorococcus abundance. A regional study in the eastern North Atlantic gyre demonstrated that the highest rates of N2 fixation occurred with the highest dFe concentrations (9.8 nM N L-1 h-1, 0.6 nM respectively). No increase in primary production following additions of trace metals (Co, Cu, Fe, Zn) was observed. The addition of N resulted in an increase in primary production. However, there was no synergistic effect of trace metal plus N addition, suggesting that alleviation of N-limitation shifted the system to P-limitation. On a meridional transect from ~ 50°N–50°S in the Atlantic Ocean, the highest concentrations of dCo (> 80 pM) coincided with low-O2 (< 150 μM) upwelled water. The lowest dCo (< 20 pM) was observed in the eastern North Atlantic gyre. Lateral advection of continental Co and upwelling were identified as important sources of Co. The highly efficient recycling of Co in the euphotic zone is an important additional source.

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<p> Government agencies assess the biological integrity of streams and the chemistry of groundwater to monitor anthropogenic impacts on freshwater ecosystems. Some of the impacted streams lack obvious stressors that can be linked to the impacts. In the case of elevated nutrients and ionic concentrations found in impacted stream sites within the Malibu Creek Watershed, research from the Las Virgenes Municipal Water District pointed towards the naturally occurring leachate from the Modelo formation, which contests previous studies suggesting an influence from anthropogenic activity. Differentiating between natural sources of trace element concentrations and point/non-point source contamination could aid in resolving water quality issues since monitoring occurs near anthropogenic development. Water, bedrock, and diatoms were sampled from spring, seep, and stream sites underlain by Tertiary sedimentary bedrock throughout the study area. Multivariate analyses revealed an association of groups driven by salinity along with a correlation between geochemistry and diatom assemblages. Mixing models and radar charts identified potential rock types as sources for analyte concentrations. Sites that were underlain by the Modelo formation presented brackish water conditions and high nutrient concentrations, which potentially influenced the diatom species compositions found at the spring/seep sites as a result of weathering.</p>

Consistent with the presence of CH$\sb4$ oxidizing bacteria at the sediment-water interface in a north Florida flooded forest and in Everglades Cladium marshes with peat soils, CH$\sb4$ emitted from the flood water was enriched in $\sp{13}$C relative to sedimentary CH$\sb4$. In contrast, CH$\sb4$ emitted from the flood water over Everglades marl soils, where CH$\sb4$ oxidizing bacteria were absent, was not enriched in $\sp{13}$C relative to sedimentary CH$\sb4$. / Stable isotopes gave no indication that CH$\sb4$ oxidation was occurring in the rhizosphere of Everglades Cladium marshes. Rhizospheric oxidation did not cause $\sp{13}$C enriched CH$\sb4$ to enter the plant and be emitted to the atmosphere. The carbon and hydrogen stable isotopic composition of sedimentary CH$\sb4$ was the same in marl and peat soils and gave no evidence that CH$\sb4$ oxidation affected the bulk sedimentary CH$\sb4$. Rhizospheric oxidation in Cladium was either not occurring due to O$\sb2$ limitation or occurred quantitatively in discrete zones imparting no isotopic signal to sedimentary CH$\sb4$. / A carbon budget developed for the flooded forest indicated that the carbon remineralization rate of soil organic matter was dependent on the hydo condition (flooded/dry) of the forest. The rate under dry conditions was 33.72 mol C m$\sp{-2}$ yr$\sp{-1}$, 3 times greater the rate under flooded conditions (11.92 mol C m$\sp{-2}$ yr$\sp{-1}$). Under flooded conditions a significant amount (48%) of the carbon remineralization was via non-methanogenic (presumably mostly aerobic) processes. / Due to the presence of insoluble organic surface films on the flood water in the flooded forest, which retard the transfer of gases across the water-air interface, calculation of fluxes from Fick's First Law overestimates the diffusive flux of CH$\sb4$ and CO$\sb2$ from the flood water to the atmosphere. The measured diffusive flux of CH$\sb4$ and CO$\sb2$ and 1.7 $\pm$ 1.7 and 3.9 $\pm$ 1.1 times less than the respective calculated flux. Consistent with surface films inhibiting the transfer of the larger and heavier CO$\sb2$ to a greater extent than CH$\sb4$, surface films also inhibited the transfer of $\sp{13}$CH$\sb4$ to a greater extent than $\sp{12}$CH$\sb4$. / Source: Dissertation Abstracts International, Volume: 53-11, Section: B, page: 5601. / Major Professor: Jeffrey P. Chanton. / Thesis (Ph.D.)--The Florida State University, 1992.

After the Deepwater Horizon (DWH) blowout, MC252 crude oil was washed onto the shores of the northeastern Gulf of Mexico. Weathered oil was buried in sandy Florida beaches in the form of sands covered by oil films, small oil particles, large agglomerates and oiled sand layers. While oil films and oil particles were observed to degrade relatively quickly, larger buried sand and oil agglomerates (SOA) can persist in the dry beach sand, where they are protected from photodegradation and mechanical stress. To determine the degradation of such large agglomerates, a time series study was initiated that quantified the weight loss and compositional changes of MC252 standardized sand and oil agglomerates (sSOAs) buried at 5, 15, 25, 35, and 45 cm depths in dry beach sand at Pensacola Beach, Florida. Sets of 10 experimental, standardized SOAs were removed at 2 - 6 month intervals over a time period of 3 years. Analysis of the sSOAs revealed a total weight loss of 10.85% or 3.66 g per sSOA volume and a loss in petroleum hydrocarbons of 59% or 2.85 g per sSOA/ over the three-year burial period. Decay rate constants for saturated hydrocarbons (C15-C40) of the surface layer of the sSOAs averaged 0.0043 d-1 (SE = 0.0017) for initial 181-day period, and 0.0027 d-1 (SE = 0.0004) for the thee-year observation period (C15-C40). PAH initial decay was 0.022 d-1 (SE = 0.004) for the initial (181-day) decay and 0.005 d-1 (SE = 0.001) for three-year period for the compounds that could be detected in the sSOA surface layer (biphenyl, acenaphthylene, acenaphthene, fluorine, dibenzothiopene, phenanthrene, pyrene, benzo(c)phenanthrene, chrysene, 7,12-dimethylbenz(a)anthracene, benzo(b,j,k)fluoranthene, benzo(a)pyrene, and benzo(g,h,i)perylene) in the surface lay. The results indicate that buried larger SOAs persist in the dry beach sands for years despite access to oxygen in contrast to oil films on sand grains and buried small oil particles that at Pensacola Beach disappeared within a year. Causes for the slow degradation of larger SOAs in the beach include the lack of photodegradation, the protection from mechanical disintegration, as well as low nutrient and moisture concentrations in the sand. / A Thesis submitted to the Department of Earth, Ocean and Atmospheric Science in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester 2018. / May 14, 2018. / BP Oil, degradation, oil decay, polycyclic aromatic hydrocarbons, saturated hydrocarbons, sediment / Includes bibliographical references. / Markus H. Huettel, Professor Directing Thesis; Ian R. MacDonald, Committee Member; Yang Wang, Committee Member; Olivia U. Mason, Committee Member.

Peatlands contain a significant amount of the global soil carbon, but the climate feedback affecting carbon stability within these peatland systems is still relatively unknown. Organic matter composition of peatlands plays a major role in determining carbon storage, and while high latitude peatlands seem to be the most sensitive to climate change, a global picture of peat organic matter chemistry is required to gauge overall peatland stability and to improve models of greenhouse gas emissions fueled by soil carbon decomposition. The goal of this research is to test the hypothesis that carbohydrate content, an indicator of soil organic matter lability or reactivity, will be lower in carbon deposits near the equator and greater in high latitude peatlands. Conversely we hypothesize that peat aromatic content will be higher at low latitudes relative to higher latitudes. As a part of the Global Peatland Microbiome Project (GPMP), around 1400 samples of peat across a latitudinal gradient from 79N to 65S were measured with Fourier transform infrared spectroscopy (FTIR) to examine the organic matter functional groups of peat. Carbohydrate and aromatic content, as determined by FTIR, are useful proxies of decomposition potential and recalcitrance, respectively. A highly significant relationship was observed between carbohydrate and aromatic content, latitude, and elevation. Carbohydrate contents of high latitude sites were significantly greater than at sites near the equator, in contrast to aromatic content which showed the opposite trend. It was also clear that at locations with similar latitudes but different elevations, the carbohydrate content was higher and aromatic content was lower at higher elevations. Higher carbohydrate content at higher latitudes indicates a greater potential for lability and resultant mineralization to form the greenhouse gases, carbon dioxide and methane, whereas the composition of low latitude peatlands is consistent with their apparent stability in the face of greater temperatures. The combination of low carbohydrates and high aromatics at warmer locations near the equator could foreshadow the organic matter composition of high latitude peat transitioning to a more recalcitrant form with a warming climate accompanying the evolution of greenhouse gases. / A Thesis submitted to the Department of Earth, Ocean and Atmospheric Science in partial fulfillment of the requirements for the degree of Master of Science. / Spring Semester 2018. / April 16, 2018. / Decomposition, FTIR, Latitude, Organic Matter, Peatlands, Stability / Includes bibliographical references. / Jeffrey Chanton, Professor Directing Thesis; Robert Spencer, Committee Member; Olivia Mason, Committee Member.

The distribution of iron in three different environments has been studied in an attempt to understand what processes control its concentration in the open ocean. In the Ochlockonee Estuary, dissolved Fe concentrations are dominated by a high molecular weight colloidal fraction ($>$10,000 molecular weight) that is also significant in controlling the dissolved organic carbon concentration. These Fe-oxyhydroxides are greater than 80% removed before the salinity reaches open ocean values. In the eastern Atlantic ocean, surface water Fe concentrations are controlled by atmospheric deposition of Saharan dust as evidenced by a strong correlation with Al. The concentration of Fe in the surface waters of the Sargasso Sea show a large variation between spring and fall with the highest concentrations in the fall correlating with a time of high atmospheric deposition. During this period of elevated surface water concentrations, between 60 and 80 percent of the Fe is not truly dissolved but colloidal in size (between 1000 molecular weight and 0.45 $\mu$m). The colloidal size fraction plays a significant role in the dissolved Fe cycle when concentrations greatly exceed saturation ($>$1 nM). / Source: Dissertation Abstracts International, Volume: 56-12, Section: B, page: 6619. / Major Professor: William M. Landing. / Thesis (Ph.D.)--The Florida State University, 1995.