Master of Science in Environmental Science, Youngstown State University, 2024, Department of Physics, Astronomy, Geology and Environmental Sciences

This research project is the establishment of a clandestine grave site, known as the “body farm”, for future geophysical and geochemical studies that will examine the long- term influence of seasons and its relationships between geophysical signatures and volatile organic compound (VOC) emissions from a simulated clandestine grave site that uses buried pig cadavers as human analogues. The objective and motivation of this research is to establish the body farm which will be used in future research that will provide detailed information to government law enforcement agencies that can be used to improve their planning efforts and their ability to locate homicide victims buried in clandestine graves. A simulated clandestine grave site was constructed with 20 graves, five graves were left empty to act as a control, and the other 15 graves contained pig proxies. Given the various scenarios of homicide victims, the different scenarios were simulated at the site involving pigs that are naked, clothed, clothed warped in tarp, and clothed covered in hydrated lime. Future research will conduct seasonal data collection of samples to determine the long term and seasonal relationship between decomposition and geophysical and chemical signatures. Future geophysical data will be collected with geophysical instruments such as ground penetrating radar (GPR), electromagnetic induction (EMI), and high sensitivity magnetic gradiometer. Future chemical analysis will be collected through constructed piezometers and analyzed using Gas Chromatography-Mass Spectrometry (GC-MS) methods. The outcomes from this research will be used by law enforcement agencies and investigators to analyze changes in the long-term seasonal characteristics of VOC emissions and geophysical signatures associated with decomposing pig cadavers. These findings can be used to further improve law enforcement training and their approaches to locate homicide victims located in the subsurface.

Committee: Jeffrey Dick PhD (Advisor); Tom Jordan PhD, PG (Committee Member); Harry Bircher P.E. (Committee Member); Billie Spieler PhD (Committee Member) Subjects: Chemistry; Environmental Geology; Environmental Science

Master of Science, The Ohio State University, 2024, Chemical Engineering

Hydrogen and Syngas are versatile chemicals dense in energy with numerous applications in the industry. Reducing the carbon footprint of their production can help counter global warming. Since conventional methods using fossil fuels lead to copious amounts of CO2 emissions, using renewable, carbon-neutral fuel sources like biogas and biomass while sequestrating CO2 can make the process carbon-negative. This can be achieved using multi-reactor iron oxide chemical looping (CL) systems. A 3-reactor Chemical Looping Hydrogen Generation System (CLHG-3R) generates a pure stream of Hydrogen, and a 2-reactor system converts biomass to high-purity syngas efficiently. The reactor conditions are optimized in this study to account for the high composition variability of these feedstocks. These fuels although renewable, have their challenges. Biogas contains high amounts of CO2 and numerous trace impurities while tars are formed significantly during biomass gasification. Chemical looping systems have a proven capability of dealing with these issues. Experimenting with process parameters like reactor temperatures, residence times, feed composition and flowrates of reactants leads to optimizing the system.

Committee: Nicholas Brunelli (Committee Member); Liang-Shih Fan FREng (Advisor) Subjects: Chemical Engineering

MS, Kent State University, 2022, College of Arts and Sciences / Department of Chemistry and Biochemistry

Liquid crystals (LCs) are at the forefront of technology today. From LC displays in smartphones and televisions to “smart glass” windows, LCs are found in technology all around us. LCs offer a variety of uses due to their birefringent properties that act at room temperature. These properties show an optical change at room temperature with a small change from external stimuli. These stimuli can include temperature, electric field, and the presence of volatile organic compounds (VOCs). This work looks at projects which focus on how to best package LCs to work as sensors to their external stimuli, as well as new ways to record their detection. The first project covered in this work looks at electrospun fibers with a nematic LC core and polymer sheath as VOC sensors. It has been shown in the past that these electrospun fiber mats show an optical response to VOC exposure, but there was little quantitative work one to show the true sensing abilities of these fiber mats. This work uses the change in the LC core's electrical properties to measure the change in resistivity of the fiber mat as it was exposed to acetone. The results of these experiments are promising as the fiber mat detector had a comparable sensing ability to that of commercial VOC sensors. While the fiber mats had a good sensing ability, they are thin and likely not durable enough to be made into clothing. Putting cholesteric LC on the outside of thread, though, has shown promising results to be woven and retain temperature sensing capabilities. This project builds off of a previous project done in the group to coat thread in LC and a polymer. This LC clad fiber would then be woven into a textile. The purpose was to evenly coat the fiber and LC with no beading. Then, a polymer coating was needed to contain the LC so that it would not wash or be rubbed off. This project is still ongoing in the group. These projects aim to use LCs as sensors in a new way. By containing the LC within a fiber or within (open full item for complete abstract)

Committee: Dena Agra-Kooijman (Committee Member); John West (Advisor) Subjects: Physical Chemistry

Master of Science, The Ohio State University, 2017, Food Science and Technology

Roasting is a critical step comprising of a series of complex reactions that are responsible for flavor generation in coffee. This study presents a real-time analytical technique that predicts the mechanism of volatile generations during different roasting conditions which could be ultimately used for online process control to deliver a more consistent target roast profile. The objectives of this research were to 1) To monitor the volatile compound generation during coffee roasting in real-time using online SIFT-MS 2) To investigate the influence of the time-temperature process during coffee roasting on the kinetics of volatiles generated and develop predictive models to determine kinetic parameters of volatile compounds and 3) predict temperature distribution histories within the coffee bean at different roasting conditions. Colombian Arabica coffee beans were roasted in a horizontal drum roaster at 210, 220 and 230 °C for 10, 15 and 20 minutes respectively. The concentrations of 7 volatile organic compounds (VOC's), with impact on coffee flavor, were measured in the gas stream at the exit from the roaster using online Selected Ion Flow Mass Spectrometry (SIFT-MS) and were compared to the amounts retained in the final coffee extract. Modified Gompertz and Logistic models were used to describe the rate of volatile generation and estimate the kinetic parameters for the Volatile Organic Compounds (VOC's) during different roasting conditions. The activation energy coefficients were calculated using the Arrhenius relationship. A transient heat conduction model for unsteady state heat transfer was used to determine the temperature distribution within the coffee bean. A synergy existed between the VOC release pattern in the roaster gas and the VOC formation/retention trend in the coffee extract. Excessive roasting (230 °C beyond 15 minutes), led to lower VOC concentrations in the roaster gas and the coffee extract. The modified Logistic models provided good statistical (open full item for complete abstract)

Committee: Dennis Heldman PhD (Advisor); Sudhir Sastry PhD (Committee Member); Simons Christopher PhD (Committee Member) Subjects: Food Science

Doctor of Philosophy, University of Akron, 0, Polymer Engineering

A new, simple, and efficient Gas Jet Fiber (GJF) spinning process was used for fabrication of polymer precursor fibers from polymer precursor sol solutions with diameters ranging from a few hundreds of nanometers to a few micrometers, which on subsequent calcination in air resulted in the production of semiconducting metal oxides (SMO) nanofibers. One of the primary objectives of this research work was to fabricate SMO nanofibers for use in photocatalytic oxidation of toxic volatile organic compounds (VOCs) that cause indoor air pollution and to degrade organic pollutants in water treatment applications. Another objective was to create specific arrangements of inorganic oxide or ceramic components in the same nanofibers so as to obtain morphologies that exhibit interesting physico-chemical properties useful in photocatalytic applications. The basic strategy adopted in this work included a synergy of wet precursor sol-gel chemistry and GJF spinning followed by thermal treatment for the synthesis of ceramic nanofibers. First, we investigated and optimized the process for fabrication of titanium dioxide (TiO2), vanadium pentoxide (V2O5), and tin-doped indium oxide (ITO) nanofibers. TiO2 nanofibers exhibited a significantly higher (i.e., almost one order of magnitude) UV-light driven ethanol photocatalytic oxidation rate compared to a commercial grade P25 TiO2 nanoparticles. Second, the production of SMO nanofibers with core-shell (CS) and side-by-side (SBS) configurations was studied for a pair of inorganic oxides. TiO2, ITO, and V2O5 were used for fabrication of bi-component CS and SBS nanofibers. Third, the fabrication strategy for hierarchical V2O5-TiO2 nanostructure from a homogeneous sol solution of a mixture of SMO precursors and polymer in volatile solvents was developed. Nanofibers were successfully obtained with diameters below 200 nm exhibiting a hierarchical `nanorods-on-nanofiber' morphological form as a result of calcination of (open full item for complete abstract)

Committee: Sadhan Jana Dr. (Advisor); Darrell Reneker Dr. (Committee Member); George Chase Dr. (Committee Member); Steven Chuang Dr. (Committee Member); Xiong Gong Dr. (Committee Member); Bryan Vogt Dr. (Committee Chair) Subjects: Chemical Engineering; Chemistry; Nanoscience; Nanotechnology; Polymer Chemistry; Polymers

Doctor of Philosophy, The Ohio State University, 2015, Environmental Science

Volatile organic compounds (VOC) and their reaction products are ubiquitous in earth's atmosphere and play many important roles leading to implications in climate change as well as public health. The many significant consequences of VOCs and their reaction products merit considerable study. However, understanding of the emissions, chemistry reaction pathways and dispersion of many VOCs is very limited due to the short lifetimes of many of them, as well as complex, nonlinear environmental and chemical phenomena, such as light dependence, turbulence, and temperature, which can impact their emission, reaction and movement. Current data is limited due to the difficulty and expense inherent in robust observation campaigns to collect data on emission, concentration and fluxes of VOCs, and few models have included very many high-resolution processes that can affect VOCs. We have developed the Hi-Resolution VOC Atmospheric Chemistry in Canopies (Hi-VACC) model to study the emission, chemistry and dispersion of BVOC at a very high spatial resolution (on the order of 1m3) and fast time scale. We have developed the model to get the necessary meteorological and atmospheric variables from the output of a previously run large eddy simulation (LES) model, and have adapted emissions and chemistry modules to handle all processes. As a result, Hi-VACC can incorporate the effects of real canopy structure, light attenuation, high-resolution turbulence, horizontal and vertical heterogeneity, and complex VOC emission schemes in modeling the emission, chemistry and dispersion of VOCs. We have used Hi-VACC to investigate the impact of vegetation-induced turbulence around small lakes on the interpretation of flux measurements of emissions from small lakes; and to determine good locations for measurement tower placement in such lakes to minimize these effects which skew measurements. We have also used Hi-VACC to investigate the sensitivity of glyoxal and isoprene flux from forest canopies (open full item for complete abstract)

Committee: Gil Bohrer (Advisor); Peter Curtis (Committee Member); Gajan Sivandran (Committee Member); Barbara Wyslouzil (Committee Member) Subjects: Environmental Science

Doctor of Philosophy, The Ohio State University, 2014, Food Science and Technology

In this dissertation, the use of static headspace sampling and analysis of volatile organic compound (VOC) using selected ion flow tube-mass spectrometry (SIFT-MS) has been proven to be rapid and efficient. The determination and discrimination of VOC profiles from each eye, blind and split areas within a cheese from a given factory was successfully made. VOC profile inhomogeneity was evident in cheeses between factories. Evaluation of biochemical pathways leading to the formation of key VOCs, differentiating the split from the blind and eye segments within factories indicated release of additional CO2(g) by-product. Results suggest a factory-dependent cause of split-formation that could develop from varied fermentation pathways in the blind, eye and split areas within a cheese block. The variability of VOC profiles within and between factories exhibit varied biochemical fermentation pathways that could conceivably be traced back in the cheese making process to identify parameters responsible for split defect. Moreover, cheese samples from 4 manufacturing stages, out-of-press, end of pre-cool, end of warm room and at time of cutting, were obtained and analyzed for VOC profiling using SIFT-MS. Significant discrimination of the VOC profiles among the stages was observed, suggesting a varied VOC behavior in each manufacturing stage. The VOC profile of cheese from the end-of-warm room was highly discriminatory; there was an increased inhomogeneity in VOC profiles between vats toward the final manufacturing stages. Variabilities were most probably related to varied fermentation activities, changes in microflora, biochemical factors, and physical and environmental conditions. Finally, a more basic approach in the analysis of VOC using SIFT-MS was done to validate the methodology used in this study. Binary aqueous mixtures of randomly selected pure VOCs were prepared and analyzed. The impact and extent of reaction of an increasing concentration of a given VOC to another (open full item for complete abstract)

Committee: W James Harper (Advisor); Sheryl Barringer (Advisor); John Litchfield (Committee Member); C. Lynn Knipe (Committee Member); Christopher Simons (Committee Member) Subjects: Food Science

PhD, University of Cincinnati, 2014, Medicine: Molecular Genetics, Biochemistry, and Microbiology

Volatile organic compounds (VOCs) are the primary constituent of a complex molecular signature that emanates from human breath and other bodily effluents. Buried within the complex combination of VOCs that are emitted from individuals are unique combinations, or signatures, that reveal both uniqueness of that individual and their overall physiological state. Since the times of Hippocrates, particular disease states in humans have been correlated with a particular smell or scent that arise due to changes in the metabolic and physiological processes resultant of those diseases. Most studies of VOC-linked disease signatures have investigated chronic infections, cancers, and metabolic disorders with little connectivity to other infection related metabolic phenotypes. Within this dissertation, we begin the daunting task of investigating VOC acute phase signatures related to infection using five highly virulent bacteria; Yersinia pestis, Francisella tularensis, Burkholderia mallei, Burkholderia pseudomallei, and Bacillus anthracis. Employing optimized dosing regimens that recapitulated primary pulmonary infections in two different strains of mice (C57BL/6J and DBA/2J), we were able to compare and contrast temporal signatures of disease progression. In the first study, we performed multiplexed serum chemokine/cytokine analysis in murine models to establish baseline immunological response phenotypes. Survival analysis of mouse groups revealed a conserved resistant phenotype in C57BL/6J females across pathogens, with the exception of F. tularensis. This enabled disambiguation of beneficial and detrimental host responses along with the identification of cytokines that served as good prognosticators of mortality. Small data set topological analysis was performed to identify genetic contributions to survival across agents, identify dose response effects, and assess temporal effects of complex cytokine/chemokine signatures between agents. We explored whether classification of (open full item for complete abstract)

Committee: Anil Menon Ph.D. (Committee Chair); Edmund Choi Ph.D. (Committee Member); Gary Dean Ph.D. (Committee Member); Jane Strasser Ph.D. (Committee Member); Richard Thompson Ph.D. (Committee Member) Subjects: Molecular Biology

MS, University of Cincinnati, 2006, Engineering : Environmental Engineering

Publicly Owned Treatment Works (POTWs) have come to be examined by the EPA as a major source of Hazardous Air Pollutant (HAP) emission. The 1990 Clean Air Act Amendments as well as state and local regulations, has required POTWs to implement maximum achievable control technologies, MACT, to meet the new regulations. A majority of the HAPs that are emitted are Volatile Organic Compounds (VOCs). Many of these HAPs are considered to be carcinogens or precursors to ozone formation. VOC emission from wastewater treatment plants can occur through a variety of mechanisms including volatilization, evaporation, biodegradation, and photodecomposition; of which, volatilization being the most significant occurring largely in the aeration basins. HAPs are stripped from wastewater in low concentrations over a large surface area. The low concentration and large area make it extremely inefficient and costly to treat polluted air using conventional methods. Recent studies have shown that off gas can be greatly reduced by using a circulating aeration system (CAS). A circulating aeration system requires the capture of off-gas at the aeration basin by an enclosure and the circulation of a percentage back through the system. Fresh air would be mixed; in proportion to the wasted off-gas, with the circulated gas, while only a fraction of the off-gas would be emitted to the atmosphere. Circulating aeration system recycles a percentage of the off-gas back into the system. The use of a CAS lengthens the retention time and increases the possibility for further biodegradation breakdown of compounds. The off gas control also becomes more manageable. With a higher off gas concentration, conventional methods of pollutant control become more economical and efficient. Effects of a CAS are compound specific, however biodegradation rates appear to improve and emissions are reduced drastically. Compounds of high degradability and high volatility, biodegradation are significantly improved. Compounds, s (open full item for complete abstract)

Committee: Dr. Tim Keener (Advisor) Subjects: Environmental Sciences

PhD, University of Cincinnati, 1999, Engineering : Environmental Engineering

Increasing regulatory pressure for VOC emissions reduction has accelerated the development of more cost effective VOC air pollution control (APC) technologies. Biofiltration is a viable technology to fill this role, for the purification of air streams polluted with biodegradable VOCs. In the biofilter, these pollutants diffuse from the air stream into a stationary mass of moist biological film, where they are oxidized by enzymatic catalysis at ambient pressures and temperatures. Properly operated, this natural, biological mineralization process will produce only benign by-products, such as inorganic salts, carbon dioxide, and water, with some additional biomass. Although research into the science and development of the technology of biofiltration has been performed for over fifteen years, biofiltration remains not widely accepted as a proven technology for VOC APC. This perception is especially true for applications treating high influent VOC concentrations and requiring high VOC removal efficiencies. This research was undertaken to develop a new, cost effective biofiltration technology which can reliably treat air streams polluted with high VOC concentrations and achieve very high removal (elimination) efficiencies. Investigations were made to evaluate different biological attachment media, in order to identify the medium most suited to such an application. Using this medium, a reliable biofiltration technology was developed and extensively tested, which can achieve the goal of reliably treating high concentrations of VOCs at high loadings with high removal efficiency. Techniques for the management and control of the accumulating by-product biomass were developed. Procedures are presented for the calculation of VOC solubility and biological kinetic parameters, at the biofiltration operating temperature. A procedure for estimating the upper limit for biofiltration for the influent air VOC concentrations is presented. A simple, explicit biofilter design equation was (open full item for complete abstract)

Committee: Makram Suidan (Advisor) Subjects:

Master of Science, Miami University, 2004, Paper Science and Engineering

In this study, a low temperature catalytic oxidation process was investigated for the oxidation of dimethyl sulfide using titania-based catalysts. TiO2 catalysts doped with vanadia were made using a wet incipient method and a flame synthesis method. The catalysts were characterized using XRD, Raman spectroscopy and BET surface area analysis to study the TiO2 phase transition as functions of calcination temperature and V/Ti mass ratio. A flow reactor was used to investigate the performance of the catalysts, and the exit gases were analyzed using gas chromatography. It was found that low concentrations of vanadia (V/Ti mass ratio ≤ 2%) inhibited phase transformation and sintering, which resulted in more activity per unit mass of the catalysts, and the catalysts having a V/Ti mass ratio of 2% were able to degrade dimethyl sulfide most efficiently.

Committee: Catherine Almquist (Advisor) Subjects:

Master of Science (MS), Wright State University, 2012, Earth and Environmental Sciences

Constructed wetlands are an efficient and cost effective means for chlorinated aliphatic hydrocarbon remediation, and will therefore continue to gain momentum as an accepted treatment by the US EPA (U.S. EPA, 1995; Amarante, 2000; Lien, 2001; WETPOL, 2009). The treatment options for chlorinated aliphatic hydrocarbons (CAHs), including wetlands, capitalize on aerobic/anaerobic interfaces in which bacterially mediated reduction-oxidation reactions degrade pollutants (Li, 1997; Bradley, 1998; Lorah and Voytek, 2004; Amon, 2007; Imfeld, 2008). In August 2000, researchers at Wright State University (WSU) combined efforts with the United States Air Force Institute of Technology (AFIT) to construct a pilot-scale upward-flow treatment wetland on Wright-Patterson Air Force Base with parameters that could remediate perchloroethene (PCE) found in a nearby aquifer (Amon et al., 2007). Eleven studies of short duration have since documented the existance of anerobic and aerobic interfaces by measuring various terminal electron acceptors (sulfate, nitrate, methane, iron) and numerous other parameters. The studies evaluated PCE degradation rates, geochemical profiles, hydraulic conductivity and chlorinated ethene concentrations. (Bugg, 2002; Opperman, 2002; Clemmer, 2003; Kovacic, 2003; BonDurant, 2004; Sobolewski, 2004; Lach, 2004; Schlater, 2006; Mohamud, 2007; Waldron, 2007, Corbin, 2008). The present research has attempted to compile, organize, and re-analyze the data collected by AFIT and WSU researchers during 2001-2006. Data was analyzed using Jenks Optimization (goodness of variance fit) method to identify and remove outliers. Meta analysis of CAH concentrations and redox parameters was performed by creating data subsets of individual piezometer and depths, influent to effluent transect data and ArcGIS maps. The present analysis concludes that a fully functioning wetland with strongly reducing geochemical conditions and flow patterns capable of PCE destruction (open full item for complete abstract)

Committee: Abinash Agrawal Ph.D. (Advisor); Christina Powell Ph.D. (Committee Member); Songlin Cheng Ph.D. (Committee Member) Subjects: Biogeochemistry; Earth; Environmental Engineering; Environmental Geology; Environmental Science; Environmental Studies; Freshwater Ecology; Geochemistry; Geographic Information Science; Soil Sciences

Master of Arts, University of Toledo, 2012, Geography

The typical approach to mapping groundwater contaminant plumes involves drawing plume contours out to each contaminant's site-specific cleanup criterion. Cleanup criteria differ between contaminants, sites and U.S. states. For this reason, it is difficult to determine which monitoring wells, plumes and sites are most contaminated within a given area or region. For the same reason, it is also difficult to determine which individual contaminant is most concentrated within a single monitoring well. The Contaminant Exceedance Rating System (CERS) was developed to address these issues by normalizing groundwater contaminant data against their site-specific cleanup criteria. Each contaminant's laboratory analytical result is divided by its respective site-specific cleanup criterion and the result is a unitless ratio which is then compared against other CERS Values. The CERS Values are then ranked into a set of CERS Ranking Categories for data grouping purposes and ease of mapping. The CERS was successfully implemented utilizing data from the Former Wurtsmith Air Force Base (WAFB) in Oscoda, Michigan (provided by the Air Force Center for Engineering and the Environment[AFCEE]). Basewide groundwater volatile organic compound (VOC) data from Summer/Fall 2009 was utilized. ESRI¿¿ ArcGIS Version 10.0 was used to map the resultant CERS Values, symbolized by their Ranking Categories. By implementing the CERS, the following were successfully determined for this data: the most concentrated contaminant in each sample, the most contaminated well(s) within each site, the most contaminated wells on the entire base, and the most contaminated plumes on the base. It is recommended that the CERS be further implemented using additional temporal data from the Former WAFB. It is also recommended that the CERS be implemented using contaminant data from other Department of Defense (DoD) installations. The CERS could allow for comparison of maximum degree of contamination between entire installa (open full item for complete abstract)

Committee: Patrick Lawrence PhD (Committee Chair); Peter Lindquist PhD (Committee Member); Robert Beckwith PG (Committee Member) Subjects: Chemistry; Environmental Economics; Environmental Management; Environmental Science; Environmental Studies; Geochemistry; Geographic Information Science; Geography; Hydrologic Sciences; Hydrology; Information Science; Information Systems; Natural Resource Management; Water Resource Management