Master of Science in Engineering, University of Akron, 2020, Civil Engineering

Excess phosphorous in water ways is known to be a cause of harmful algal blooms. These blooms have caused problems with water aesthetics and recreational use. Water Treatment Residual (WTR) has been shown to have an affinity for phosphorous. Since WTR is a bi-product of the drinking water treatment process it has the potential of being a low-cost alternative to remove excess phosphorous from water ways, potentially preventing harmful algal blooms. A previous study proved there was a beneficial reuse for WTR produced at the Akron Water Treatment plant for binding excess phosphorous. This research thesis looked further into Akron Water Treatment Plants WTR, to see if baking could increase its phosphorous adsorption capacity. Initial 24-hour sorption studies determined optimal baking temperatures of 175°C for Al-WTR (ce = 0.31 mg/L, qe = 117.21) and 150°C for PAC-WTR (ce = 0.20 mg/L, qe = 120.00). Isotherm studies for baked Al-WTR (175°C) and PAC-WTR (150°C) found that there was a net desorption of phosphorous when in distilled background solution. A statistical analysis across all experimental conditions determined that baked PAC-WTR (mean qe 11.00 mg/kg) performed significantly (ρ < 0.05) better than baked Al-WTR (mean qe 8.18 mg/kg). When the specific condition of the isotherm experiments were considered, baked PAC-WTR sorbed more PO4 (mean qe 36.64 mg/kg) (ρ < 0.05) when subjected to raw water at 20°C and static in conditions. Baked Al-WTR was the next best (mean qe 21.42 mg/kg) significantly (ρ < 0.05) in 5°C Static in raw water. Continuous flow column tests were also conducted to find the sorption maximum of the baked WTR, and to compare the adsorption capacity of As-Is WTR versus baked WTR conducted. Baked WTR was found to have an affinity for phosphorous with a sorption capacity of 7.91 mg-P/g-WTR for baked Al-WTR and 16.21 mg-P/kg-WTR. When compared to As-Is WTR, baked PAC WTR was the only material found to have a higher adsorption capacity by (open full item for complete abstract)

Master of Science, The Ohio State University, 2023, Food, Agricultural and Biological Engineering

Interest in agricultural soil health and quality has encouraged farmers across the world to adopt soil health management practices, such as no-till or reduced tillage and cover crops. In-spite of the growing adoption of soil health practices, few studies have focused on their impact on soil and water quality after long-term adoption. To assess the effects of soil health practices, soil and water samples were collected over two years from three paired sites, each representing three different land use management scenarios: (1) agricultural fields with conventional crop rotation and management, (2) agricultural fields with 15 to 45 years of soil health management adoption, and (3) forest soils near each pair of agricultural fields. A combination of 52 soil health indicators were analysed including: microbial communities, enzyme activities, phospholipid fatty acid (PLFA), soil respiration, bulk density, macronutrients, and micronutrients. Edge-of-field and surface runoff analysis included total nitrogen (TN), total phosphorus (TP), nitrate, and dissolved reactive phosphorous concentrations during dry and wet periods over the course of a year. Results suggest that long-term soil health management had little impact on soil health indicators when compared to conventionally managed farms but did reduce TP, TP, nitrate leaching, and water loss. However, further evaluation of the soil health indicators revealed some promising relationships between soil health and water quality. When compared to the forested systems, both agricultural systems were found to have significantly lower biological quality. These results provide some evidence to support the implementation of soil health practices in agricultural fields and a perspective on long-term agricultural management practices compared to native natural soil health.

Master of Science (MS), Bowling Green State University, 2022, Geology

The Western Lake Erie Basin (WLEB) has been experiencing harmful algal blooms due to increases in dissolved reactive phosphorous (DRP) from agricultural land in the Maumee River watershed. Agricultural best management practices (BMPs) can be useful to mitigate the DRP loads; nevertheless, DRP is not always fully removed by in-field BMPs. Phosphorous (P) removal structures can be filled with phosphorus sorption materials (PSM) such as iron and aluminum oxides and can be placed at the junction of runoff and subsurface drainage to trap DRP from tile drainage. However, dissolved organic matter (DOM) from the agricultural farmland might compete with phosphate ions (PO43-) at the adsorption sites in the media, reducing its lifetime and efficiency. Therefore, laboratory flow-through column experiments were conducted to determine whether DOM is affecting P sorption onto iron enhanced activated alumina media (Alcan). The experiments were informed by field data collected from a regional farm. Alcan (Al/ Fe (hydro) oxides) media was efficient in removing PO43- coming into the filtering system and thereby, flow-through column experiments were able to determine a discrete P removal percentage efficiency of 83.32%, 68.26%, 66.54%, 57.16% and 41.27% by the end of treatment I (5mg L-1 PO43- only), treatment II (5mg L-1 PO43- and 5 mg L-1 DOM), treatment III (5mg L-1 PO43- and 10 mg L-1 DOM), treatment IV (5mg L-1 PO43- and 20 mg L-1 DOM), and treatment V (10mg L-1 PO43- and 20 mg L-1 DOM), respectively. Moreover, from exponential regression analysis of P removal curves for each treatment, it was measured that a total cumulative of 231.45 gm, 92.65 gm, 92.06 gm, 65.998 gm and 91.476 gm of P per kg PSM can be added to treatment I, II, III, IV and V, respectively, until the media gets fully saturated, i.e., concentration of influent PO43- would be equal to the effluent PO43- concentrations. It is evident that DOM is competing with PO43- decreasing PO43- sorption onto the Alcan media. (open full item for complete abstract)

Master of Science (MS), Bowling Green State University, 2020, Geology

Annually, nearly 1.5 million tons of sediments are dredged from Lake Erie, Ohio. The main method of dredged sediment disposal is open lake disposal. Open lake disposal poses a threat to water quality by re-suspending nitrogen and phosphorus-rich sediments. The Ohio State Senate passed a bill to prohibit the practice of open water disposal after July 2020 and recommends finding alternatives uses of the dredged sediment. One alternative is to use the sediment as an amendment for farm soil. This research aimed to measure the health of soil amended with various dredged sediment ratios, determine nutrient dynamics when the soil blends were subjected to induced storm-events, and quantify the effect of dredged sediment on soybean belowground biomass and yield. We used de-watered dredged sediment from the Great Lakes Dredged Material Center for Innovation and farm soil from a legacy phosphorous (P) farm site in Oregon, Ohio. Soil analysis was conducted on the two soils for baseline data. The soils were thoroughly mixed and separated into four different soil blends; 100% farm soil, 90% farm soil to 10% dredged sediment, 80% farm soil to 20% dredged sediment, and 100% dredged sediment and placed into 32 mesocosms. Soybeans were planted in half of the mesocosms. Daily watering and five random seasonal storm events were conducted during the growing season using synthetic rainwater. After 123 days, the soybean plants were harvested, and soil cores were collected for analysis. Physico-chemical analyses were conducted on the soil, plant biomass, and percolated stormwater. Results showed that dredged sediment amendment improved the quality of the farm soil by providing additional soil organic matter, increasing the cation exchange capacity and decreased P concentration in the legacy P farm soil. Nutrient loss (phosphorous and nitrogen) in the percolated solutions showed no significant changes when compared to the percolated solutions in the 100% farm soil treatment, indicating no s (open full item for complete abstract)

Doctor of Philosophy, The Ohio State University, 2019, Environment and Natural Resources

Soil health is an emerging framework that seeks to integrate the physical, chemical, and biological components of soil. It is defined by the USDA as “the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans”. The breadth of this definition has allowed “soil health” to become a context-specific definition, letting soil health be defined in terms of the desired outcomes. In the context of agronomic nutrient management, the primary desired outcome is a tightening of the nutrient cycle to minimize losses to the environment. Here, I use the framework of soil health to understand how soil health indicators influence and are influenced by on-farm nutrient management practices. Three separate studies were conducted to: 1) understand the factors influencing the efficacy of the most widely used biological soil health metric, mineralizable carbon, 2) determine the effect of 12 years of phosphorus (P) restriction on biological and physical soil health in three Ohio sites, and 3) integrate biological soil health indicators into nitrogen (N) management strategies across the Corn Belt. The first study found that mineralizable C was variable across and within soil test labs. However, even after controlling for variations in methodology, a significant amount of the variability was soil-specific. The second study found very few effects of P restriction on soil biological and physical health. However, P restriction slightly increased organic P stocks and resulted in consistent shifts in the balance between the processed and easily-metabolized portions of the active C pool. In the third and final study, an increase in soil biological health was shown to increase the yields for a given N fertilization rate, as well as having slight predictive abilities in predicting whether a site would be responsive to N fertilization. This study also showed that soil biological health may be slightly increased at moderate N fertilization rates. C (open full item for complete abstract)

PhD, University of Cincinnati, 2010, Arts and Sciences: Chemistry

Metallomics is the study of the metallome, interactions, and functional connections of metal ions and other metal species with genes, proteins, metabolites, and other biomolecules in biological systems. Its application can handle a variety of sample, from biomedical to environmental. Elemental speciation is a fundamental component of the concept of Metallomics. It permits to investigate the chemical form of metals and metalloids containing species. Speciation analyses with metallomics approaches can be performed best by high performance liquid chromatography (HPLC) coupled to inductively coupled plasma mass spectrometry (ICP-MS). HPLC represents a suitable separation technique and a variety of different chromatographic techniques, from conventional to capillary, can be applied to obtain good baseline separated peaks corresponding to different species. ICP-MS is the state-of-the-art instrument when elemental mass spectrometry for the detection of ultra trace levels (parts per quadrillion) takes place. ICP-MS is renowned for its phenomenal sensitivity and selectivity as elemental analyzer. Chromatography can be applied to molecular mass spectrometry as well. In the presented works electrospray ionization is the technique of choice. Nano liquid chromatography-Chip-electrospray ionization- ion trap mass spectrometry (NanoLC-Chip-ESI-ITMS) is an excellent tool for the research performed. The aforementioned instrumentations have been applied to environmental applications in the first part of this dissertation. Chemical warfare agents (CWAs) are present in the environment (sea and soil) because discarded due over production during World War I and II. Those CWAs easily degrade, especially in aquatic surrounding, and give birth to chemical warfare agent degradation products (CWADPs) whose toxicity is not well know. In the following pages a complete study about some of these CWADPs and their speciation and toxicity is reported. The second part of the dissertation analysis (open full item for complete abstract)

Master of Science (M.S.), University of Dayton, 2012, Civil Engineering

Nutrient contamination, specifically regarding nitrogen and phosphorous, is widely recognized as an environmental concern. A significant and currently unregulated portion of nutrient pollution is produced from agricultural non-point sources. Previous studies have identified possible methods for treating nutrients from agricultural runoff; however, few studies have produced a treatment system capable of removing both nitrogen and phosphorous. Additionally, several previous studies utilized treatment methods which were expensive or difficult to maintain. The purpose of this study was to research several laboratory scale treatment systems in an effort to identify sustainable methods for treating nitrogen and phosphorous from synthetic agricultural runoff. Three laboratory scale treatment configurations were developed and examined to determine the effectiveness of biological treatment methods. Configuration #1 consisted of an anaerobic denitrification biofilter with wood chip media. Configuration #2 included an anaerobic denitrification biofilter with corn residue media. Finally, Configuration #3 consisted of an aerobic nitrification trickling filter with shredded tire media as well as an anaerobic denitrification biofilter with wood chip media. Synthetic agricultural runoff was conveyed through each configuration for four weeks, and samples were collected to measure the influent and effluent nutrient concentrations. Assessments of the sample data included advanced statistical analyses. Additionally, a laboratory scale adsorption experiment was conducted to determine how effectively physical treatment methods reduce phosphorous contamination. Using crushed gypsum as the test substance, a series of adsorption isotherms were conducted by combining various masses of gypsum with test solutions of various phosphate concentrations. Samples were taken from each of these combinations to measure the adsorption of total phosphorous and reactive phosphorous over time. Data was (open full item for complete abstract)

Master of Science (M.S.), University of Dayton, 2011, Chemical Engineering

Polyurethanes are known to be the largest fuel loads which can easily ignite and once it ignites, lead to flashover, burning at fast rates. In the presence of fire these foams have a tendency to drip and flow as they burn. Commercially available fire retardants for polyurethane foams are in need of replacement due to negative environmental impact, especially chlorinated and brominated compounds. The purpose of this project was to study the existing commercially available flame retardants, as well as to synthesize new non-halogenated flame retardants for polyurethane foams which utilize char formation as the primary mechanism of flame retardancy. The new phosphorous and boron based flame retardants were tested for heat release with a micro combustion calorimeter (ASTM D7309). The results showed that the addition of boronic acids greatly lowered the heat release, due to condensed (char formation) phase mechanism. The new FR's were also solvent blended in Texin 990R (mimic for polyurethane foam) and tested for heat release and the results indicated that the boronic acids showed significant reduction in flammability.

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2006, Biological Sciences

Low Fe availability constrains algal primary production in numerous oceanic provinces. Although not numerically abundant, the diatom microplankton (> 20 micro m) are important contributors to new production in these regions. To better understand the contributions made to new production by diatoms in Fe-depleted waters, this dissertation work addressed the Fe-specific physiological and biochemical autecology of this group. A field component consisted of two research cruises in 2002 and 2003 along a transect at 29 degrees North spanning the eastern half of the Central North Pacific (CNP) gyre, and focused on the vertically migrating bouyant giant diatom genera Rhizosolenia spp. and Ethmodiscus spp. The lab component examined physiological, biochemical and growth responses of large open-ocean and coastal diatom isolates to perturbations of Fe in the growth medium. Whereas mats of Rhizosolenias howed elevated values (ca. 0.61, n = 88) of Fv/Fm, a measure of photochemical energy conversion efficiency, along the easterly transect from Hawaii to San Diego, a clear decline in this parameter measured at locations west of 165 degrees West provided physiological evidence of nutrient limitation. By contrast, cells of Ethmodiscus showed consistently near maximal values of Fv/Fm (ca.0.7, n = 70). The higher Fv/Fmassociated with Ethmodiscus was supported in part by an enhanced Ferredoxin Index (Fd Index), a common biochemical measure for Fe status. By comparison, the Fd Index for Rhizosolenia along the western reaches of the transect was consistently depressed. Cellular Fe quotas of both diatoms rinsed with oxalate, a reagent used to reduce cell surface adsorbed Fe facilitating its removal from the cell surface, demonstrated comparable low Fe:C stoichiometry (means of 5.41 SE 4.76 and 9.21 SE 5.10) (micro mol:mol) for Ethmodiscus and Rhizosolenia, respectively. This was consistent with the presumed low dissolved Fe content of these ultraoligotrophic waters. These cellular Fe quota (open full item for complete abstract)

Doctor of Philosophy (Ph.D.), Bowling Green State University, 2013, Photochemical Sciences

Because breaking and making of chemical bonds lies at the heart of chemistry, this thesis focuses on dynamic studies of labile molecules in solutions using ultrafast transient absorption spectroscopy. Specifically, my interest is two-fold: (i) novel reaction intermediates of polyhalogenated carbon, boron and phosphorus compounds; (ii) photophysics and photochemistry of labile copper(II) halide complexes. Excitation of CH2Br2, CHBr3, BBr3, and PBr3 into n(Br)σ*(X-Br) states, where X=C, B, or P, leads to direct photoisomerization with formation of isomers having Br-Br bonds as well as rupture of one of X-Br bonds with the formation of a Br atom and a polyatomic radical fragment, which subsequently recombine to form similar isomer products. Nonpolar solvation stabilizes the isomers, consistent with intrinsic reaction coordinate calculations of the isomer ground state potential energy surfaces at the density functional level of theory, and consequently, the involvement of these highly energetic species on chemically-relevant time scales needs to be taken into account. Monochlorocomplexes in methanol solutions promoted to the ligand-to-metal charge transfer (LMCT) excited state predominantly undergo internal conversion via back electron transfer, giving rise to vibrationally hot ground-state parent complexes. Copper-chloride homolitical bond dissociation yielding the solvated copper(I) and Cl- atom/solvent CT complexes constitutes a minor pathway. Insights into ligand substitution mechanisms were acquired by monitoring the recovery of monochloro complexes at the expense of two unexcited dichloro- and unsubstituted forms of Cu(II) complexes also present in the solution. Detailed description of ultrafast excited-state dynamics of CuCl42-complexes in acetonitrile upon excitation into all possible Ligand Field (LF) excited states and two most intense LMCT transitions is reported. The LF states were found to be nonreactive with lifetimes remarkably longer than those (open full item for complete abstract)