Master of Science, The Ohio State University, 1961, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1925, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1918, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 1922, Graduate School

Committee: Not Provided (Other) Subjects:

Doctor of Philosophy, The Ohio State University, 2019, Public Health

Background: Occupational exposure to airborne chemical agents is a concern for thousands of workers in the United States. Regulatory limits determine the level at which workers may be exposed to chemical agents, and exposure over these limits may indicate a risk for health hazards. The main purpose of this study was to evaluate exposure to specific airborne chemical agents by industry group, by occupation group, and over time using occupational exposure monitoring data in order to determine potential groups of workers that should be targeted for intervention and future research. In addition, this study used an auto-coding program in order to code the free text job descriptions to standardized occupation codes for the first time, as only industry was provided as a standardized code within the applied dataset. Methods: The study employed the Occupational Safety and Health Administration (OSHA) Integrated Management Information System (IMIS) and Occupational Safety and Health Information System (OIS) databases to evaluate personal air monitoring samples taken from 1979 through 2015. The OSHA IMIS/OIS is the largest occupational exposure database in the United States. Analyses were conducted in SAS. Exceedance fractions over an agent's threshold limit value (TLV) or permissible exposure limit (PEL) were calculated through frequency analyses and linear regression was used to determine changes in geometric mean of exposure level over time. Statistical procedures included using logistic regression and mixed-model analyses to obtain odds ratios for the likelihood of exposure over an agent's TLV or PEL in comparison to other industry or occupation groups. The NIOSH Industry and Occupation Computerized Coding System (NIOCCS) version 3.0 was used to auto-code free text job descriptions into standardized occupation codes. Results: Examination of benzene, toluene, ethyl benzene, and xylene (BTEX) occupational exposure indicated that manufacturing industry groups inclu (open full item for complete abstract)

Committee: Michael Bisesi PhD (Advisor); John Crawford PhD (Advisor); Carolyn Sommerich PhD (Committee Member); Christopher Weghorst PhD (Committee Member); Olorunfemi Adetona PhD (Committee Member) Subjects: Occupational Health; Public Health

Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1980, Graduate School

Committee: Not Provided (Other) Subjects: Chemistry

Doctor of Philosophy, The Ohio State University, 1973, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Doctor of Philosophy, The Ohio State University, 1970, Graduate School

Committee: Not Provided (Other) Subjects: Engineering

Master of Science in Engineering, University of Akron, 0, Civil Engineering

Extraction and recovery of asphalt binders is an important procedure, although the rheological properties of the recovered binder may vary from the actual values due to many factors. This study has been conducted to evaluate the effect of different chemical solvents on the rheological properties of the recovered asphalt binder at high, intermediate, and low temperatures excluding the other factors that may affect the results. Five different binders were taken into consideration when this study was conducted, PG 58-28, PG 64-22, PG 64-28, PG 70-22, and PG 76-28, along with three different types of chemical solvents largely used as an industrial solvent, which are Trycoloroethelene (TCE), N-Propyl Bromide (nPB) brand called Entron-AE and Toluene. To catch the effect left by these solvents on the recovered binders, each binder has been dissolved in a specific amount of each of the three chemical solvents individually, the proportions of the solvent to the asphalt binder used was almost equal to the amount of the solvent needed to extract the same amount of binder out of a mixtures using a centrifuge. After leaving it for a while and making sure that the binder is totally dissolved, the binder is then recovered using a normal distillation process called the Abson method. In order to determine whether the age of the binder affects the results obtained from the recovered binders or not, testing has been done on unaged binders, short term aged binders, and long term aged binders, and in order to do that, short term aging has been simulated using the Rolling Thin Film Oven Test (RTFO), and the long term aging has been simulated using the Pressurized Aging Vessel (PAV). Finally, both original and recovered binders were tested at different aging conditions using the Dynamic Shear Rheometer (DSR), and the Bending Beam Rheometer (BBR). Data were used to obtain a full continuous grading of both the original (base) binder and the recovered binder for the five diffe (open full item for complete abstract)

Committee: Ala Abbas Dr. (Advisor); Anil Patnaik Dr. (Committee Member); Zhe Luo Dr. (Committee Member) Subjects: Civil Engineering

MS, University of Cincinnati, 2016, Engineering and Applied Science: Environmental Engineering

Trichloroethylene (TCE) is a widely used industrial solvent and one of the most frequently detected volatile organic compounds (VOCs) in water, air and soil. Its harmful health effects on humans affecting every core systems of the body and its potential carcinogenicity makes TCE a toxic compound whose removal from these vital resources is necessary. Biotrickling filters have proven to be more economic and efficient while eradicating harmful VOCs as compared to other technologies like incineration. This research analyzes the effectiveness of biotrickling filtration technology to biodegrade TCE from the feed air streams. Two biotrickling filters were seeded with fungi strains and were maintained at pH 4 by a nutrient solution containing formate buffer, crucial minerals and vitamins. This solution was nozzle sprayed on the bed at a rate of 2 L/d. The air streams entered the systems at an empty bed residence time of 2 mins. These streams were spiked with the liquid VOCs through syringe pumps. Furthermore, as TCE is a hydrophobic non-beneficial carbon source for microbes, starvation was chosen as the biomass control strategy. Initially, a spatial analysis was performed using ArcGIS to study TCE distribution across mainland USA and the industrial discharge per individual state for 2007. According to the density maps obtained, the Midwestern, Eastern and Pacific Western states were particularly contaminated with TCE, with most of the densely contaminated locations coinciding with Superfund sites. Subsequently, the co-metabolic removal of TCE in biotrickling filter systems was assessed with the feed consisting TCE and methanol (co-metabolite). Two biotrickling filters were fed with different methanol:TCE ratios – Biofilter I with 70:30 feed ratio and Biofilter II with 80:20 ratio. Each system was fed with various influent VOC concentrations distributed across four phases each. The main objective of this study was to obtain the VOC loading rates at which efficient elimina (open full item for complete abstract)

Committee: George Sorial Ph.D. (Committee Chair); Pablo Campo Ph.D. (Committee Member); Margaret Kupferle Ph.D. P.E. (Committee Member) Subjects: Environmental Engineering

Master of Science (MS), Wright State University, 2013, Physics

This work studies the electromagnetic properties of AF455, a two photon dye, DNA bound with cetyltrimethyl ammonium (CTMA), in liquid solvent blends for use in thin film optical filters. The liquid properties of the materials are believed to be transferred to the films. The solvent blends used are ratios of toluene (T) and dimethyl sulfoxide (DMSO). The complex permittivity and permeability of the samples are measured using the short open coaxial line technique in the frequency range of 1.0 x 107 Hz to 2.0 x 109 Hz. In this frequency range, AF455 does not act as a two photon absorber. The results show there is an interaction between AF455 and DNA-CTMA that increases the real permittivity for two solvent blends (50-50, and 60-40, T-DMSO). There is also a clear conformation change in the samples with the solvents and DNA-CTMA only that is observed in the real permittivity. In the 70-30 blend, the conformation of the DNA-CTMA is a clear helix. In the samples with less toluene the conformation of the DNA-CTMA is a coil structure. The imaginary permittivity increases with the addition DNA-CTMA. The real and imaginary permeability are constant across all samples.

Committee: Gregory Kozlowski Ph.D. (Advisor); Angela Campbell Ph.D. (Committee Member); David Stewart Ph.D. (Committee Member); Douglas Petkie Ph.D. (Committee Member) Subjects: Electromagnetics; Electromagnetism

Master of Science in Engineering, University of Toledo, 2013, College of Engineering

Colloidal gold nanoparticles may be used in a variety of applications ranging from solar cells to sensors to catalysis and drug delivery. In particular, ordered gold nanoparticle thin-films have been proposed as efficient coupling layers which may be used to maximize the efficiency of photovoltaic solar cells. In addition, recently a drop-drying method to self-assemble a well-ordered monolayer of Au nanoparticles has been developed. In this method, a monodisperse solution of gold nanoparticles whose size has been selected via chemical synthesis, and which are coated with organic ligands to prevent aggregation and precipitation is used. Using this method a monolayer of Au nanoparticles can be made that covers the full area of a 2” silicon wafer. However, the interaction between the gold nanoparticles and the interface, which plays a key role in determining the film-quality, is not well understood. One of the main objectives of the work presented in this thesis is to obtain a better fundamental understanding of the structure and interactions of ligand-coated Au nanoparticles at a solvent-vapor interface. In particular, motivated by experimental and simulation results, we have carried out extensive molecular dynamics simulations of dodecanethiol (DDT)-coated Au nanoparticles in both bulk toluene and at the toluene-vapor interface. Our simulations were carried out using the public domain software LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) along with the OPLS (Optimized Potential for Liquid Simulation) force field which is a force-field which has been specifically developed for simulating organic liquids. Our simulations indicate that, in contrast to previous simulations of decanethiol and octadecanethiol coated Au nanoparticles in water, the dodecanethiol-coated nanoparticle (NP) sits relatively low in the toluene, such that the Au core never penetrates above the interface, while the thiols only partially stick out above the inter (open full item for complete abstract)

Committee: Jacques Amar (Committee Chair); Mohammed Niamat (Committee Member); Gursel Serpen (Committee Member) Subjects: Computer Science; Condensed Matter Physics; Physics

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:

Doctor of Philosophy, The Ohio State University, 2003, Chemistry

Advances in surface broad bandwidth sum frequency generation (BBSFG) spectroscopy and investigations of liquid surfaces are discussed in this dissertation. The technique implemented uses a double amplifier ultrafast laser system to produce a narrow bandwidth visible beam and a broad bandwidth infrared beam. The two beams are overlapped in time and space on a liquid surface to produce a broad bandwidth sum frequency signal. The double amplifier system allows for higher peak powers resulting in a stronger sum frequency generation response from characteristically low signal liquid surfaces. Several organic liquids are investigated using BBSFG spectroscopy and Raman spectroscopy to investigate the surface structure and the bulk liquids, respectively. The series of liquids selected are applicable to atmospheric aerosol processing. Initially, a surrogate hydrophilic compound ethylene glycol was investigated. In addition to ethylene glycol, several aromatic compounds were probed at their air-liquid interfaces. The aromatic compounds studied were benzene, toluene, ethylbenzene, o-xylene, m-xylene, p-xylene, and mesitylene. The final aromatic compound to be studied was 1-methyl naphthalene. The surface of the neat 1-methyl naphthalene liquid is dramatically altered upon the addition of small amounts of water into the bulk liquid.

Committee: Heather Allen (Advisor) Subjects: Chemistry, Physical

Master of Science (MS), Ohio University, 2009, Environmental Studies (Arts and Sciences)

Toluene is a major component of gasoline and is a widely used industrial solvent. It contaminates surface and groundwater and poses a menacing threat to human health. Toluene is not a carcinogen; however, in mixtures it enhances the effect of carcinogens. This research uses a molecular approach to study toluene biodegradation by the facultative, denitrifier Thauera aromatic strain T1 (T.aromatica strain T1). This strain is able to degrade toluene into non aromatic compounds under anaerobic conditions and use it as a sole carbon and energy source. Previous work identified the tutE tutFDGH gene cluster as essential for the first step of anaerobic toluene biodegradation. The aim of this research is to determine the role of selected amino acids in the function of the TutH protein in toluene biodegradation by T.aromatica strain T1. This work determined if changes can be made to certain amino acids in the TutH protein without disrupting protein function. We identified amino acids of interest by computer analysis and used site-directed mutagenesis to generate the desired changes. Based on computer analysis, I formed a hypothesis that changing the amino acid leucine at position 266 into valine , changing serine at position 5 into theronine, or changing tyrosine at position 283 into phenyalanine will not disrupt the TutH protein function. We performed site-directed mutagenesis on TutH and determined that two of these altered proteins (L266V and S5T) failed to complement a strain unable to produce TutH while altered protein containing Y283F succeeded in complementing a strain unable to produce TutH. It is important to identify tolerated amino acids because researchers can use them to change the range of substrates. This research will further the understanding of the toluene metabolism in the environment and may help in the remediation of contaminated sites. Also, this research will contribute to the development of a more efficient toluene bio-degradation pathway. Ideal (open full item for complete abstract)

Committee: Peter Coschigano (Advisor); Michele Morrone (Committee Chair); Erin Murphy (Committee Member) Subjects: Microbiology

Doctor of Philosophy (PhD), Ohio University, 2007, Biological Sciences (Arts and Sciences)

Toluene is an aromatic hydrocarbon that is widely used in our everyday life. It is a major water-soluble constituent of petroleum and can pollute surface as well as ground waters. The toxic nature of toluene is responsible for causing severe health hazards. The study of toluene degrading bacteria has attracted attention because of their potential to clean up spills. Thauera aromaticastrain T1 is one such bacterium capable of degrading toluene under anaerobic conditions. The tutE tutFDGHgene cluster is essential for the first step of anaerobic toluene degradation in T. aromaticastrain T1. The tutF, tutDand tutGgenes are proposed to code for the three subunits of the enzyme benzylsuccinate synthase, which is involved in the initial step of anaerobic toluene degradation pathway. The tutEgene is proposed to code for the enzyme benzylsuccinate synthase activase. The precise role of the tutHgene in toluene degradation is currently unknown, but it is proposed to have an ATP/GTP binding domain and is assumed to be involved in benzylsuccinate synthase complex formation. This is consistent with its proposed role as a chaperone of “ATPases Associated with a Variety of Cellular Activities” (AAA) class. Work presented here demonstrates that the gene tutHis essential for toluene metabolism. A plasmid carrying an in-frame tutHdeletion was unable to produce wild-type TutH protein in a tutGchromosomal deletion background (chromosomal deletion in tutGdoes not result in production of TutH due to a polar effect on downstream genes). The resultant construct was unable to complement a polar tutGchromosomal mutation, indicating the importance of tutHin toluene degradation. Further, site-directed mutagenesis was used to identify amino acids in TutH that are essential for toluene metabolism. The TutH putative ATP/GTP binding domain was disrupted by changing glycine, lysine and serine at positions 52, 53 and 54 to alanine, arginine and alanine respectively. Additionally, other amino acids wh (open full item for complete abstract)

Committee: Peter Coschigano (Advisor) Subjects:

Master of Science (MS), Ohio University, 1984, Chemical Engineering (Engineering)

The effect of carrier gas velocity and the solvent content in the carrier gas on the drying of poly(methyl metha- crylate)-toluene solution was studied by using a Du Pont 951 Thermogravimetric Analyzer and a Perkin-Elmer model 330 spectrophotometer. The solvent evaporation flux was plotted against the average carrier gas velocity and against the value {(Ps-Pg)/Ps}×100%, where Ps is the saturated vapor pressure of toluene at the experiment condition and pg is the vapor pressure of the carrier gas, at different concentrations in the duration of drying. The result shows that the solvent content in the carrier gas and the velocity of the carrier gas have negligible effect on the second stage of drying. Also, the results suggests that the development of a large concentration gradient at the surface of the polymer solution, which is due to the high evaporation flux at the surface, will cause % a skin effect which resists further solvent removal from the polymer solution. And this suggests that we could get to a certain desired concentration at a minimum of time by controlling the drying conditions during the time of drying.

Committee: John Collier (Advisor) Subjects: Engineering, Chemical

Master of Science, University of Akron, 2010, Chemistry

A method for solventless extraction and determination of gasoline components in water has been developed. This method uses silicone polycarbonate permeation membranes to extract the components, and collect them on a Tenax TA adsorbent. Samples were thermally desorbed into a gas chromatograph with flame ionization detection for separation and determination of the components. Time-weighted average (TWA) concentrations were determined by plotting the amount of analyte collected versus the product of concentration and time (ppb•hr). A linear response was seen in the TWA curves for benzene, toluene, ethylbenzene and the three isomers of xylene (BTEX). These components had detection limits from 1.4 ppb for m- and p-xylene to 2.7 ppb for toluene. The effects of temperature and common environmental contaminants were examined. The advantages of this method include being environmentally friendly due to the lack of solvent and having less steps for analysis than many standard methods.

Committee: James Hardy PhD (Advisor) Subjects: Analytical Chemistry; Chemistry; Environmental Science; Experiments