Master of Science (MS), Ohio University, 2015, Geological Sciences (Arts and Sciences)

Available U–Pb age data for the Cornubian Batholith of SW England is based almost entirely on monazite and xenotime, and very little zircon U–Pb age data has been published. As a result, no zircon inheritance data are available for the batholith, by which the nature of the unexposed basement of the Rhenohercynian Zone in SW England might be constrained. Zircon LA-ICPMS data for the Cornubian Batholith provides Concordia ages (Bodmin Moor granite: 316 ± 4 Ma, Carnmenellis granite: 313 ± 3 Ma, Dartmoor granite: ~310 Ma, St. Austell granite: 305 ± 5 Ma, and Land's End granite: 300 ± 5 Ma) that are consistently 20-30 Ma older than previously published emplacement ages for the batholith and unrealistic in terms of geologic relative age relationships. Several of the batholith's granite plutons contain a component of late-Devonian inheritance that may record rift-related, lower crustal melting or arc-related magmatism associated with subduction of the Rheic Ocean. In addition, the older granites likely contain Mesoproterozoic inheritance, although the highly discordant nature of the Mesoproterozoic ages precludes their use in assigning an affinity to the Rhenohercynian basement in SW England. Submitted for publication in Tectonophysics as “Neace, E.R., Nance, R.D., Murphy, J.B., Lancaster, P., Shail, R.K. (2016). Zircon LA-ICPMS geochronology of the Cornubian Batholith, SW England.”

Committee: Richard Nance (Advisor); Craig Grimes (Committee Member); Douglas Green (Committee Member) Subjects: Geological; Geology

Doctor of Philosophy, The Ohio State University, 2024, Materials Science and Engineering

This dissertation will center around the discussion of the investigation into the anomalous thermal and electrical transport phenomena in magnetic Weyl semimetal, YbMnBi2, as well as the characterization of its magnetization behavior. A theory-based experimental search for a new type of chiral anomaly in promising materials will also be covered. 1. Thermoelectrics (TEs) are solid-state devices that can realize heat-electricity conversion. Transverse TEs require materials with a large Nernst effect, which typically requires a strong applied magnetic field. However, topological materials with magnetic order offer an alternative pathway for achieving large Nernst via the anomalous Hall effect and the accompanying anomalous Nernst effect (ANE) that arise from band topology. Here, we show that YbMnBi2 with a low Hall density and a chemical potential near the Weyl points has the highest ANE-dominated Nernst thermopower of any magnetic materials, S_yx around 110 μV/K (T = 254 K, 5 T ≤ |(μ_0)*H| ≤ 9 T applied along the spin canting direction), due to the synergism between classical contributions from filled electron bands, large Hall conductivity of topological origin, and large resistivity anisotropy. In addition, an appreciable thermal Hall angle of 0.02 < ∇yT/∇xT (–9 T) < 0.06 was observed (40 K < T < 310 K). 2. How exactly the magnetization of YbMnBi2 changes with temperature and magnetic field remains indeterminate. Mysteries exist in the previous reports. Herein, through extensive magnetization characterization at various conditions, it was found that the magnetization behavior of YbMnBi2 showcases shared features in many aspects among multiple crystals in spite of a few sample-dependent details. The findings here hint at a more complex picture of the magnetic structure than what is currently known. This project hopefully can provide a foundation for future studies on thoroughly characterizing the magnetization behavior of YbMnBi2. 3. Chiral anomaly, a signat (open full item for complete abstract)

Committee: Joseph Heremans (Advisor); Maryam Ghazisaeidi (Committee Member); Michael Sumption (Committee Member); Roberto Myers (Committee Member) Subjects: Condensed Matter Physics; Materials Science; Physics

Doctor of Philosophy, The Ohio State University, 2024, Environmental Science

Historical and current anthropogenic activity combined with land turnovers and rampant vacancies have increased human exposure risk to contaminants. This exposure risk disproportionately affects lower income communities and can have detrimental impacts on human health, particularly children. A management solution is needed to address this widespread contamination of vacant lots. Additionally, federal and state regulators continue to lower residential soil Pb standards which will likely require new risk-based approaches to address urban soil Pb contamination. This dissertation examines three different amendment types (P amendments, Fe oxide containing amendments, and potassium permanganate (KMnO4)) for their ability to address urban Pb soil contamination and reduce human health exposure risk. Remediation strategies that can address both organic and inorganic pollutants are also needed. This is addressed in Chapter 3. This dissertation is written as a series of manuscripts to be submitted to the appropriate journals; this will be reflected by slight differences in formatting. In Chapter 1, readily available P sources (biosolids incinerator ash, poultry litter, biosolids compost, and triple super phosphate) of varying solubility were assessed as soil amendments to reduce Pb bioaccessibility and serve as an inexpensive remediation strategy for urban soil. Contaminated soil from Cleveland, OH was treated with the P soil amendments at a 1:5 Pb:P molar ratio and incubated for 3 months. A slurry analysis was also conducted to assess reduction in bioaccessible Pb independent of time. Pb bioaccessibility was evaluated using US EPA Method 1340 at pH 1.5 and the Physiologically Based Extraction Test (PBET). Treatments were largely found ineffective regardless of IVBA extraction method, incubation duration, slurry analyses, or P source. Method 1340 had one significant treatment (combined poultry litter and BIA) but only resulted in a 8% IVBA Pb reduction. The same treatmen (open full item for complete abstract)

Committee: Nicholas Basta (Advisor); Brian Lower (Committee Member); Steven Lower (Committee Member); Darryl Hood (Committee Member) Subjects: Environmental Science; Soil Sciences

PhD, University of Cincinnati, 2023, Medicine: Industrial Hygiene (Environmental Health)

Background Lead (Pb) is an environmental toxin primarily known for its neurotoxicity in children. Exposure to Pb and blood Pb levels have dropped significantly since the removal of Pb from many consumer products in the 1970s and 1980s; however, damage done to the central nervous system cannot be repaired. Additionally, Pb can be stored in bone tissue for decades and elevated BLLs have been associated with decreased BMD and disrupted bone metabolism. Women experience higher rates of falls and fractures compared to men due to hormonal changes during menopause. Women with early-life exposure to Pb may be predisposed to instability which may lead to falls and subsequent fractures. Methods A literature review was conducted with SCOPUS, PubMed, Embase, and Web of Science to find childhood populations that measured prenatal and early-life Pb exposure and assessed neuromotor and postural balance. STROBE quality review was used to assess the risk of bias of each study. Subjects were recruited using last known mailing address, email address, and phone number. Average childhood BLL from ten days of age to five years of age was used to characterize childhood exposure to Pb. Static and dynamic balance assessments were performed in Kettering Laboratory using force platform posturagraphy and an iTUG test. Four test conditions were used to test the sensory afferents related to balance. Bone damping capacity was measured using BSA test. An ELISA-type method was used to measure markers of bone resorption (CTX-1) and bone formation (P1NP) from blood samples. Measures of bone quantity (BMD and geometric parameters of bone) were measured and analyzed at CCHMC by technologists. A multivariate linear regression with backward elimination stepwise regression was used to understand the relationship between childhood BLLs and adult bone and balance outcomes. Results Few studies found a significant relationship between cord Pb levels and childhood neuromotor outcomes. BLLs (open full item for complete abstract)

Committee: Amit Bhattacharya Ph.D. (Committee Chair); Barbara Alexander Ph.D. (Committee Member); Jagjit Yadav Ph.D. (Committee Member); Marepalli Rao Ph.D. (Committee Member); Rachael Nolan Ph.D. M.P.H. (Committee Member) Subjects: Environmental Health

Doctor of Philosophy, Miami University, 2023, Geology and Environmental Earth Science

This dissertation comprises three studies that apply radiogenic isotope and elemental geochemistry as essential tools to investigate natural and anthropogenic processes. The first project investigates two fundamental petrological problems, the origin of a compositional gap (i.e., the “Daly Gap”) between the mafic and felsic compositions of volcanic rocks, and the production of felsic magmas in basaltic oceanic island environments. At Santa Barbara volcano on Terceira Island, Azores, eruptive products range from basalt to rhyolite but exhibit a scarcity of intermediate rocks, thus forming a “Daly gap”. This compositional gap, however, is largely filled if syenite (plutonic) nodules found in pumice deposits are considered. Geochemical and thermodynamic modeling, and Sr, Pb and Nd isotopic analyses indicate that the Daly gap results from melt viscosity and water content variations during fractional crystallization of a parental basalt as it evolves to felsic compositions. The second study examines the magmatic evolution of Morne Patates volcano on Dominica, in the Lesser Antilles island arc. Dacitic lava dome blocks contain mafic enclaves. Petrologic observations and geochemical analyses suggest that mafic enclaves represent globules of mafic magma that were injected into and mingled with the host felsic reservoir. Sr, Pb, and Nd isotope ratios of Morne Patates host dacites suggest a petrogenetic relationship with the nearby Morne Plat Pays volcano. However, isotopic variability of the mafic magmas suggests that they originate from multiple geochemically and isotopically distinct reservoirs. Trace element and isotope modeling results reflect sediment-derived melts that were incorporated into a slab-fluid hydrated mantle wedge beneath Dominica. The third project is a case study to test the utility of Sr and Pb isotopes as potential tracers of wine origin. Strontium and Pb isotope analyses were performed on wine, soils, grapes, and other samples from a vineyard (open full item for complete abstract)

Committee: Elisabeth Widom (Committee Chair); Mark Krekeler (Committee Member); Jason Rech (Committee Member); James Oris (Committee Member); Zilda França (Committee Member) Subjects: Geochemistry; Geology

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

Lead (Pb) introduced by anthropogenic activities is a prominent ongoing environmental concern especially for young children who can ingest it directly through hand-to-mouth activities and are most susceptible to the harmful lifelong effects of Pb poisoning. This study involved determining Pb concentrations in soil cores sampled from the surface to root depths at community garden sites in the Toledo, OH area. While these gardens have many positive effects on their communities, they provide a potentially ready source of Pb to children and adults. A total of 277 soil samples were analyzed from nine different community garden sites, six of the sites had soils with Pb concentrations above background levels and three had soils with Pb concentrations exceeding the USEPA action level of 100 ppm. The sites with elevated Pb levels were located in socioeconomically depressed older neighborhoods and the soils that had actionable Pb levels were from present or prior drip zones. The primary source of the Pb being from past use of Pb-based paints. The Pb concentration varied with depth typically increasing at the base of raised beds due to mixing with underlying original soil. The vertical transport of the Pb is due to mechanical processes associated with gardening practices. Community outreach was an important component of this study and the results were presented individually to the garden managers along with recommendations on how to minimize Pb exposure at those sites that had soils with elevated Pb levels. The most important considerations being to identify and avoid drip zones and to collect not just surface samples but also down to root depths.

Committee: John Farver PhD (Committee Chair); Ganming Liu PhD (Committee Member); Kurt Panter PhD (Committee Member) Subjects: Environmental Geology; Geology

Doctor of Philosophy, Miami University, 2022, Geology and Environmental Earth Science

Volcanic rocks record the complex nature of magmatic systems. The mineralogical, petrological, and geochemical heterogeneity that exists within an eruptive unit at a single volcano is challenging to reconcile with a static magma chamber model. Current understanding, therefore, supports the presence of complex, dynamic trans crustal magmatic systems (TCMSs) that consist of interconnected regions of magma storage where liquid-poor, crystal-rich mushes exist and variably interact. This dissertation presents an investigation into the magmatic and crustal components of TCMSs through a study of andesitic-dacitic lavas, hornblendite cumulates, and crustal xenoliths from the Plio- Pleistocene Pampa Aullagas (PA) and Quillacas (QL) monogenetic centers on the Bolivian Altiplano, Central Andes. In Chapter 1, amphibole's role in continental arc petrogenesis is investigated through a textural and geochemical study of hornblendite cumulates entrained within QL lavas. Granular, idiomorphic textures, the absence of relict clinopyroxene, and mesocumulate textures defined by intercumulus feldspar, apatite, and Fe-Ti oxides all support the formation of the hornblendites as cumulates in the lower arc crust. Reaction rims associated with cumulus amphiboles record cumulate mobilization, ascent, and eruption through TCMSs over relatively short timescales (<30 days). In Chapter 2, the crustal components of the QL and PA TCMSs are investigated through a lithologically diverse crustal xenolith suite which provides insights into the tectonomagmatic history of the Central Andean continental crust. From U-Pb zircon geochronology, evidence for ~3 Ga of tectono-magmatic events is recorded within the Central Andean continental basement. Age population peaks correlate with global supercontinent cycles, including the establishment of Nuna, Rodinia, and Gondwana, and record a long history of terrane accretion and arc magmatism along the western margin of South America. In Chapter 3, the origin of num (open full item for complete abstract)

Committee: Claire McLeod (Advisor); Michael Brudzinski (Committee Member); Jennifer Blue (Committee Member); Alicia Cruz-Uribe (Committee Member); Mark Krekeler (Committee Member) Subjects: Geochemistry; Geology; Mineralogy; Petrology

Bachelor of Science (BS), Ohio University, 2022, Geological Sciences

The Tavsanlı Zone high-pressure/low-temperature (HP/LT) metamorphic belt exposed in NW Turkey represents the subducted northern margin of the Anatolide-Tauride Platform. The subduction of the Anatolide-Tauride Platform beneath the Pontides resulted in the closure of the Neotethys Ocean, a Mesozoic Ocean that separated Laurasia (Pontides) and Gondwana (Anatolide-Taurides). Numerous tectonic models have been proposed to explain how the closure of the ocean occurred, however, debate still exists as to the number of ocean basins and subduction zones involved and their ages. This research uses U-Pb geochronology and trace element data from zircons in three lawsonite blueschist and eclogite facies metamafic samples collected from the Tavsanlı Zone to constrain the timing of subduction initiation and metamorphism in the region. Zircons from one lawsonite eclogite sample lack older cores and yield ages of 88 Ma – 116 Ma, which are interpreted as metamorphic ages. Zircons from the other lawsonite eclogite sample and the lawsonite blueschist preserve older cores and younger rims. Core ages range from ~170 Ma – 907 Ma, whereas rim ages range from 69 Ma – 142 Ma. Probability density plots indicate common zircon growth events at ~95 Ma, ~110 Ma, ~130 Ma, and ~180 Ma. The ~95 Ma, ~110 Ma, and ~130 Ma age peaks likely represent metamorphic events, whereas the 180 Ma age peak likely represents the age of the protolith. Zircon cores with ages > 180 Ma are likely xenocrystic in origin. The U/Yb and Hf contents of the ~180 Ma zircon cores indicate that the protolith for both the lawsonite blueschist and lawsonite eclogite originated from an enriched mantle or continental source. Zircon cores with ages > 180 Ma have similar U/Yb and Hf contents as the ~180 Ma zircon cores, likely indicating a similar origin. The ~95 Ma and ~110 Ma zircon age peaks are consistent with previous 40Ar/39Ar phengite and Lu-Hf garnet and lawsonite geochronology results from the Sivrihisar Massif and indicate (open full item for complete abstract)

Committee: Katherine F. Fornash (Advisor); Eung Seok Lee (Committee Member); Alycia Stigall (Committee Member) Subjects: Geochemistry; Geology; Petrology

Master of Science, The Ohio State University, 2022, Environment and Natural Resources

Measuring the reduction of in vitro bioaccessible (IVBA) Pb from the addition of phosphate amendments has been researched for more than two decades. The mean change in IVBA Pb as a fraction of total Pb (AC) and relative to the IVBA Pb of the control soil (RC) was determined with a random effects meta-analysis. The addition of P to contaminated soils consistently reduced IVBA Pb. The mean AC was approximately -12% and mean RC was approximately -25% based on 76 soils that measured IVBA Pb with a method other than EPA Method 1340. This analysis determined that soluble amendments reduce bioaccessible Pb more than insoluble amendments, phosphoric acid is more effective than other phosphate amendments, and urban Pb contamination, associated with legacy Pb-paint and tetraethyl Pb, showed lower reductions than other Pb sources. Meta-regression identified high IVBA Pb in the control, low incubated soil pH, and high total Pb with the greater reductions in AC and RC. In order to facilitate comparisons across future remediation research, a set of minimum reported data should be included in published studies and researchers should use standardized in vitro bioaccessibility methods developed for P-treated soils. Meta-analysis identified lowered incubated soil pH as correlated with greater reductions in IVBA Pb but previous studies have found purposeful acidification to have no significant effect on IVBA Pb. In this study, three soils (IDs: AG, TH, SA), previously incubated with triple superphosphate, were acidified to pH 3 with 6M trace-metal grade HCl, and subsequently neutralized with 6M NaOH, to determine if acidification of soil influences IVBA Pb in soils amended with phosphate. The acidification of soil took varying amounts of HCl and markedly less 6M NaOH to return soils to initial pH. The treatment effect ratios (TER) for acidification and neutralization varied by soil. No significant differences were observed for any treatment in SA soil. The acidified treatments had si (open full item for complete abstract)

Committee: Nicholas Basta (Advisor); Steven Lower (Committee Member); M. Scott Demyan (Committee Member) Subjects: Environmental Science; Soil Sciences

MS, Kent State University, 2020, College of Arts and Sciences / Department of Earth Sciences

Industrialization and modernization throughout the 19th and 20th centuries resulted in lead (Pb) emissions from numerous sources, such as leaded gasoline, Pb paint, and industrial production. This resulted in the release of millions of tons of Pb byproducts into cities across the United States. Although deposition from these sources into soils largely ceased in 1996 following the phase-out of leaded gasoline, legacy Pb continues to be a risk to human health particularly in urban neighborhoods. Current practices regarding the risk of exposure to soil Pb do not address and remediate high Pb risk areas until after exposure has occurred. This project is aimed at determining how total Pb (PbT) and potentially bioavailable Pb (PbBA) concentrations are spatially distributed at the neighborhood-level in an urban environment, and potential mineralogical and geochemical controls on Pb speciation and distribution. Eighty-two soil samples were collected from Akron, OH; 30 from the Summit Lake neighborhood, and 52 from Akron Public School students' residences, primarily from West Akron. PbT was measured by X-Ray Fluorescence (XRF), and potential PbBA was determined using two methods: (1) a nitric acid solution (PbNA) extraction and (2) a simulated gastric fluid (PbGA) extraction. Extracted Pb was measured using Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES). Solid phase characterization was performed to determine soil particle mineralogy and morphology using X-Ray Diffraction (XRD) and scanning electron microscopy with electron dispersive spectroscopy (SEM-EDS). Loss on ignition (LOI) was used as a proxy to determine soil organic matter composition. PbT values ranged from 34.6 mg/kg to 1969.6 mg/kg, with an average value of 227 mg/kg (+/- 335.1 mg/kg). In total, fourteen samples exceeded the USEPA level for acceptable Pb concentrations in play soils (400 mg/kg), with nine of the fourteen samples coming from the neighborhood of West Akron. Extracted Pb values (open full item for complete abstract)

Committee: David Singer (Advisor); David Costello (Committee Member); Jeremy Williams (Committee Member) Subjects: Geochemistry; Geology

Master of Science (MS), Wright State University, 2019, Earth and Environmental Sciences

Lead (Pb) is a human-health concern, especially with regard to exposures of children. Lead contaminated drinking water is a primary route of exposure for children; however, water sampling for Pb is voluntary in schools with a public water supply. This study examined Pb in tap water from public schools around Dayton, OH. Schools were selected to span a range of ages (construction year) and community socioeconomic status. Of the 28 schools contacted, seven responded "affirmatively" to sampling, two responded "negatively", and 19 did not respond. None of the schools that were sampled had Pb concentrations exceeding the U.S. EPA guidelines for supplemental action, which is greater than or equal to 10% of plumbing fixtures exceeding 15 µg/L. Only four of 100 fixtures sampled had Pb exceeding 20 µg/L, the concentration recommended for fixture removal in schools. As expected, increased Pb levels were associated with warmer water temperatures. Water from sink faucets had greater Pb levels than water from drinking fountains, and Pb concentrations were greater in initial water sample draws versus samples collected after a 5-minute flush. To combat the leaching of Pb into school tap water, older lead and brass containing fixtures should be replaced, and changes in physicochemical parameters should be monitored to identify risks of Pb exposure.

Committee: Chad R. Hammerschmidt Ph.D. (Advisor); Silvia E. Newell Ph.D. (Committee Member); Stacey Hundley Ph.D. (Committee Member); Mark J. McCarthy Ph.D. (Committee Member) Subjects: Environmental Health; Environmental Science

Master of Science (MS), Bowling Green State University, 2019, Geology

Blood lead levels (BLLs) in children of the Toledo, OH area have been elevated for decades, and numerous studies have linked the issue to soil contamination by lead (Pb) paint and leaded gasoline. Young children below the age of 4 years have proven the most susceptible to Pb poisoning due to their high Pb absorption rates and direct ingestion of Pb contaminated sources resulting from instinctive hand-to-mouth behaviors. This problem is significant because high BLLs can result in many pathological and developmental problems including irreversible fetal brain damage, brain damage to the developing prefrontal cortex, behavioral problems, violence, learning disabilities, and more. The objectives of this study were to determine the primary factors leading to Pb and other heavy metals contamination in community gardens located at or near contaminated soils in Toledo, OH. Given the rising popularity of urban community gardens, it is also important to understand the sustainability of current gardening practices for minimizing exposure to Pb. A total of 399 samples were collected across 27 community gardens, of which 218 including the soil profiles of 14 community gardens were analyzed for heavy metals using an ICP-OES. Soil profiles were collected down to 40 cm depth (or maximum achievable depth based on the presence of buried rubble from demolished structures, buried foundations, etc.), and subsampled at 5 cm intervals to observe its distribution with depth. Using historical maps such as the Sanborn Fire Insurance maps combined with measuring the distribution of lead within gardens across properties, it was found that drip zones, a 1-meter area of soil immediately surrounding structures containing lead paint, is the main predictor for high lead levels in community gardens. And given that many gardens are located at the sites of demolished structures, historical maps such as the Sanborn Fire Insurance maps proved critical for determining the locations of drip zones a (open full item for complete abstract)

Committee: John Farver Dr. (Advisor); Peter Gorsevski Dr. (Committee Member); Yuning Fu Dr. (Committee Member) Subjects: Environmental Geology; Environmental Science; Geology; Health Sciences; Soil Sciences

Master of Science in Mechanical Engineering (MSME), Wright State University, 2018, Mechanical Engineering

Environmental and safety concerns have necessitated a phase-out of lead-based alloys, which are often used in electronics solder applications. In order to properly assess suitable replacement materials, it is necessary to understand the deformation mechanisms relevant to the application. In the case of electronics solder, creep is an important mechanism that must be considered in the design of reliable devices and systems. In this study, Power-Law and Garofalo constitutive creep models were derived for two medium temperature solder alloys. The first alloy is known by the commercial name Indalloy 236 and is a quaternary alloy of lead, antimony, tin, and silver. The lead-free alternative is a binary alloy of tin and antimony known by the trade name Indalloy 264. Constant strain rate tests were conducted at temperatures from -20 to 175 Celsius using constant strain rate tensile testing in the range of e-5 s-1 to e-1 s-1. Creep constants were defined for use in materials selection and design analysis activities.

Committee: Daniel Young Ph.D. (Advisor); Raghavan Srinivasan Ph.D., P.E. (Committee Member); Joseph Slater Ph.D., P.E. (Committee Member) Subjects: Aerospace Materials; Materials Science; Mechanical Engineering; Mechanics

Master of Science, The Ohio State University, 2018, Environment and Natural Resources

Anthropogenic use of lead has resulted in widespread soil contamination. Exposure to lead when contaminated soil is incidentally ingested with food poses a risk to both humans and wildlife. When soil is ingested, only a fraction of total Pb is bioavailable, or absorbed into the bloodstream. Conservative soil bioavailability defaults are used to calculate exposure in the absence of bioavailability data. This often overestimates exposure and risk. Generating bioavailability data allows a more accurate representation of risk, reducing cleanup costs or making sites appropriate for a wider variety of uses. However, the animal feeding studies traditionally used to generate these data are time-consuming and expensive. Extensive research has led to development and adoption of in vitro bioaccessibility assays that simulate gastrointestinal conditions to determine in vitro bioaccessible Pb (IVBA Pb), which is then used to predict relative soil Pb bioavailability (RBA Pb). These methods simulate fasting conditions and it is unclear whether they can predict bioavailability of soil Pb consumed with food. This study sought to incorporate diet into soil Pb in vitro bioaccessibility assays to simulate exposure in wildlife incidentally consuming soil while feeding and in humans eating produce contaminated with soil. To determine whether in vitro bioaccessibility assays were predictive of RBA Pb of eight soils dosed to Japanese quail (Coturnix japonica), the soils were combined with the feeding study diet and IVBA Pb determined with three in vitro bioaccessibility methods: USEPA Method 1340 at pH 1.5, USEPA Method 1340 at pH 2.5, and a newly developed Avian Ohio State University In Vitro Gastrointestinal evaluation. All methods were predictive of RBA Pb in Japanese quail (Coturnix japonica), and diet+soil methods produced somewhat stronger relationships than soil-alone methods. Seven wildlife diets were then evaluated with a single soil in the 3 previously mentioned methods to ex (open full item for complete abstract)

Committee: Nicholas Basta (Advisor); G. Matthew Davies (Committee Member); Jeffory Hattey (Committee Member) Subjects: Environmental Science

MS, University of Cincinnati, 2018, Arts and Sciences: Geology

The Cook Inlet basin, located in south-central Alaska, contains forearc basin strata that record the upper plate response to changes in subduction since 170 Ma. Subduction of normal oceanic crust during the Jurassic and Cretaceous was followed by spreading ridge subduction in the Paleocene and Eocene, which produced a shallow subduction angle and caused coeval near- trench magmatism, metamorphism, and deformation. This was followed by a period of normal subduction until the Oligocene, when subduction of the thick Yakutat plate again triggered a transition from normal to flat-slab subduction, still happening today. We study the sedimentary record of the Cook Inlet basin and analyze sediment routing, magmatic sources, and rock exhumation of southern Alaska, and their changes through time. We use a double-dating technique on single detrital zircon grains from 17 samples combining fission track and U-Pb dating. We collected Cenozoic sandstone and modern fluvial deposits in order to analyze spatial and temporal changes of the sediment record. Seven Cenozoic samples were taken from outcrops on the northern and southern margin of the basin, and four core samples from the northern part of the basin. Six modern river sands were sampled to analyze the character of the sediment currently draining into the basin from the north, east, and south. We combine geo- and thermochronometric methods to identify sediment eroded from source rock that cooled either due to magmatic or exhumational processes. The double-dating results of our modern river sand samples show a number of magmatic and exhumational signals entering the modern Cook Inlet basin. Rivers sourced from the Talkeetna Mountains are dominated by 200–150 Ma magmatic age populations, representative of the Jurassic Talkeetna Arc. Some samples draining the accretionary prism also show similar magmatic age populations, indicating recycling of arc-derived material. Additionally, rivers sourced from the accretionary prism y (open full item for complete abstract)

Committee: Eva Enkelmann Ph.D. habil. (Committee Chair); Craig Dietsch Ph.D. (Committee Member); Emily Finzel Ph.D. (Committee Member) Subjects: Geology

Master of Science in Chemical Engineering, Cleveland State University, 2017, Washkewicz College of Engineering

The purpose of this research is to examine the dendrite array morphology, macrosegregation, and defect formation caused by the fluid flow at the abrupt cross-section changes during directional solidification of Pb-6% Sb alloy. Four 24-cm long cylindrical alloy samples were directionally solidified in graphite crucibles: two having a constant diameter (9-mm) grown at 10.4 and 63.1 μm s-1 , one having an abrupt cross-section decrease (from 12.7 to 6.35 mm) and one having an abrupt increase (from 6.35 to 12.7 mm) by pulling down the alloy containing cylindrical graphite crucibles from the upper hot-zone of a stationary vertical furnace into its cold-zone below. Microstructures were examined on transverse slices cut along the length of the directionally solidified samples. Dendrite spacing and distribution were characterized on these transverse sections. The Pb-6% Sb alloy was selected as a low melting point analog for commercially used multicomponent nickel-base superalloys, because its thermophysical properties are well characterized. Also, a density inversion occurs in the inter-dendritic melt in the “mushy-zone” during directional solidification of this alloy, because the density of the melt decreases as Sb content increases from the array tips at the top of the mushy zone to the eutectic at their bottom. In constant cross-section crucibles, the formation of dendrite-trees in the mushy zone will be subject only to this “plume type” convection as solidification proceeds from the bottom end of the crucible to its top. Whereas in crucibles with abrupt cross-section change, the solidifying mushy-zone will be subject to additional “cross-section change induced” solidification shrinkage flow, when the speed of the liquid flowing downwards to feed the solidification shrinkage occurring below, will either suddenly accelerate or decelerate, because of the abrupt area change. This sudden change in the incoming fluid speed may break slender side-branches of dendrite trees. The (open full item for complete abstract)

Committee: Surendra Tewari Ph.D. (Committee Chair); Orhan Talu Ph.D. (Committee Member); Christopher Wirth Ph.D. (Committee Member); Nolan Holland Ph.D. (Committee Member) Subjects: Chemical Engineering

Doctor of Philosophy, The Ohio State University, 2016, Environment and Natural Resources

Management of soil hazards in urban areas requires strategies that are scientifically effective and accepted by both the general public and public health regulators. Soil management options must consider all three of these components during evaluation. The concept of managing soil hazards to reduce contaminant exposure must be expanded to include considerations of soil function and soil health following remediation. Bioavailability assessments must be included with soil hazard assessments to improve hazard characterization. Soil hazard and soil health indicators can be combined in a comprehensive index, though the relative importance of each factor within the index will be site specific. Several recent studies have quantified contaminants in soil, such as lead (Pb), arsenic (As), and polycyclic aromatic hydrocarbons (PAHs), in many urban areas. When these findings are coupled with slow regulatory movement on potential management strategies, the public's perceived risk for potential exposure may increase. Such scenarios across the United States may reduce public support for widespread contaminant cleanup. Innovative interdisciplinary research initiatives are needed to: (1) evaluate potential contaminants and factors that contribute to healthy, functioning soil, (2) facilitate public and regulatory acceptance of potential soil hazards and treatments, and (3) communicate the public health implications of viable cleanup activities. These studies are particularly needed in vulnerable urban areas that demonstrate variable soil contaminant concentrations over small geographic spaces. Characterizing and addressing these soil contaminants will contribute to and benefit our society from public health, social, environmental, and economic perspectives. Soil contaminants and their impacts can be evaluated within the context of other exposures and individual characteristics, such as proposed in the developing field of exposome public health research. The results from this diss (open full item for complete abstract)

Committee: Nicholas Basta PhD. (Advisor); Steven Culman PhD. (Committee Member); Darryl Hood PhD. (Committee Member); Robyn Wilson PhD. (Committee Member) Subjects: Environmental Health; Environmental Management; Environmental Science; Environmental Studies; Public Health; Soil Sciences

PHD, Kent State University, 2016, College of Arts and Sciences / Chemical Physics

Photoalignment is a well-established technique for surface alignment of the liquid crystal director. Previously, chrome masks were necessary for patterned photoalignment but were difficult to use, costly, and inflexible. To extend the capabilities of photoalignment we built an automated maskless multi-domain photoalignment device based on a DMD (digital multimirror device) projection system. The device is capable of creating arbitrary photoalignment patterns with micron-sized features. Pancharatnam-Berry phase (PB-phase) is a geometric phase that arises from cyclic change of polarization state. By varying the azimuthal anchoring angle in a hybrid-aligned liquid crystal cell we can control the spatial variation of the PB-phase shift. Using our automated photoalignment device to align the liquid crystal arbitrary wave front manipulations are possible. The PB-phase shift effect is maximized when the cell is tuned to have a half-wave retardation and disappears at full-wave retardation, so the cell can be switched on and off by applying a voltage. Two wavefront controlled devices developed using this technique will be discussed: A switchable liquid crystal phase shift mask for creating sub-diffraction sized photolithographic features, and a transparent diffractive display that utilizes a switchable liquid crystal diffraction grating.

Committee: Hiroshi Yokoyama (Committee Chair); Phil Bos (Committee Member); Deng Ke Yang (Committee Member); Elizabeth Mann (Committee Member); Alexander Seed (Committee Member) Subjects: Chemical Engineering; Chemistry; Physics

Master of Science, University of Akron, 2016, Polymer Science

Organic semiconductors have attracted increasing attention because of their potential in making low cost, flexible and large area electronic devices. For organic field-effect transistors (OFETs), the charge transport in the semiconductor materials is not only affected by their intrinsic electronic properties, but also by their intermolecular packing mode in the solid states. Intermolecular hydrogen-bond is one of the strategy to provide extra intermolecular interaction and enhance packing of polymer chains. Inspired by our previous work1, an novel conjugated structure dithieno[3,2-b:2,3-d]Pyridin-5(4H)-one (DTP) has been synthesized and characterized. The DTP structure possesses two fused thiophene units,which can be good electron donor ,and a d-lactam unit in which can be functionalized with alkyl or t-Boc groups to provide sufficient solubility for solution processing. Originally published as a blue pigment2, Diimidazo[4,5-¿b:4',5'-m]triphenodioxazine-2,10-dione,6,14-dichloro-1,3,9,11-tetrahydro, also named Pigment Blue 80 (P.B 80) is believed to have good potential as organic electronics. The pigment molecule has big conjugated triphenodioxazine structure with two imdazo-2-one rings as hydrogen-bonding sites, as well as two chlorine atoms to provide potential in polymerization. Different routes has been tried in order to synthesis the P.B 80 molecule, an important intermediate 5-amino-6-methoxy-1,3-dihydro-2H-benzo[d]imidazol-2-one has been synthesized and characterized, and the reaction condition in critical steps has been studied.

Committee: Yu Zhu Dr. (Advisor); Coleen Pugh Dr. (Committee Member) Subjects: Chemistry; Polymer Chemistry

Doctor of Philosophy, The Ohio State University, 2015, Evolution, Ecology and Organismal Biology

Elevated soil Pb at shooting ranges presents a potential risk for wildlife living on or near ranges, with ingestion of Pb shot and contaminated soil as the main pathways of exposure. Receptors of interest for this study included earthworms, ground beetles (Carabidae) and meadow voles (Microtus pennsylvanicus). Study sites for this research included a private shooting range (1,457–10,044 mg/kg) and an off-site reference area (local park; 6–11 mg/kg) located in central Ohio, USA. The shooting range consisted of three areas: shotfall (where most Pb shot falls), extracted (where Pb shot was removed by wet sieving in 2009), and on-site reference area. Earthworm reproduction and bioaccumulation assays were conducted with soils from shooting range and off-site reference areas. Earthworm reproduction was reduced in shooting range soils. Bioaccumulation was higher for shooting range soils than off-site reference and negative control soils. Shooting range field-collected earthworm tissues had significantly higher Pb than worms collected at off-site reference area. Lead in depurated earthworms exposed to on-site reference soil and shotfall soil was lower than Pb in non-depurated earthworms exposed to the same soils. Carabids were collected using pitfall traps at the shooting range. Twenty-three genera were collected from 2010–2012 and overall taxa richness and ground beetle abundance was highest in extracted area. An indicator species analysis suggested that twelve taxa were indicators of different areas. Results suggest that disturbance of soil wet screening and subsequent grass slice-seeding in extracted area was more important in determining ground beetle abundance and diversity than soil Pb concentrations. Lead in Harpalus sp. from shooting range sites was higher than Harpalus sp. from off-site reference area. Lead in depurated beetles from extracted area was lower than in non-depurated beetles from extracted area. Voles were collected using snap-traps at shooti (open full item for complete abstract)

Committee: Roman Lanno (Advisor) Subjects: Biology; Chemistry; Ecology; Entomology; Environmental Science; Environmental Studies; Toxicology; Zoology