Physical Sciences and Mathematics Commons^™

Exploration Using Reaction Temperature To Tailor The Degree Of Order In Micro-Block Copolymer Proton Exchange Membranes, John Quentin Buquoi Iii

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The ability to control the self-assembly of sulfonated poly(arylene ether) sulfones (s-PAESs) was explored by tailoring rate coefficients, via temperature, in an A₂ + B₂ + B₂' Nucleophilic Aromatic Substitution (S_NAr) approach. The reactivity of various electrophilic sites were studied and tuned, via temperature control, to elicit a range of more ordered and disordered polymers of equivalent monomeric composition. These polymers were characterized by ¹H and ¹³C NMR spectroscopy and found to have highly disordered polymer configuration at higher temperatures while having a more regular configuration at lower temperatures.

Reservoir Analysis Of The Clinton Interval In Stark And Summit Counties, Ohio, Dominick Andrew Wytovich

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The characteristics of a sandstone reservoir of Silurian age (the "Clinton interval") were analyzed using 382 geophysical well logs from the Dominion Gas storage field located in Stark and Summit Counties, Ohio. These sandstones have long been identified by the informal drillers' terms, White, Red, and Stray Clinton. Gamma ray logs were used to analyze the distribution of net stand thickness and its relation to initial production through the construction of isopach and net sand isolith maps. I constructed eight cross sections to identify and correlate the tops of three prominent sandstones and two marine flooding surfaces to evaluate reservoir …

Functional Identification Of Microorganisms That Transform Mercury In Marine Sediments, Lisa Romas

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Monomethylmercury (MMHg) is the toxic form of mercury (Hg) that biomagnifies in food webs, and human exposure to MMHg occurs predominantly via consumption of fish. The primary source of MMHg to the marine environment is thought to be in situ sedimentary production by benthic microorganisms, namely sulfate-reducing bacteria (SRB). I collected sediments from the continental shelf (stations 2 and 6) and slope (station 9) of the NW Atlantic Ocean, and amended them with various inhibitor and promoter solutions to target specific functional groups capable of Hg transformations. I also added stable enriched Hg isotopes to quantify gross Hg methylation and …

An Investigation Of Group Developed Weighing Matrices, Jeff R. Hollon

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A weighing matrix is a square matrix whose entries are 1, 0 or -1 and has the property that the matrix times its transpose is some integer multiple of the identity matrix. We examine the case where these matrices are said to be developed by an abelian group. Through a combination of extending previous results and by giving explicit constructions we will answer the question of existence for 318 such matrices of order and weight both below 100. At the end, we are left with 98 open cases out of a possible 1,022. Further, some of the new results provide …

A Comparison Of Atmospheric Pahs In Pine Needles And High-Volume Sampler Filters In The Dayton Metro Area, Timothy A. Tomashuk

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Samples of filters from High-volume (HiVol) samplers of particulate matter (PM) with a size of 10 micrometers or less were deployed for five months in Moraine and Yellow Springs, OH, by the Regional Air Protection Control Agency and analyzed for the Environmental Pollution Agency (EPA) 16 polycyclic aromatic hydrocarbons (PAHs). Pine needles on trees near the HiVol samplers were also collected and analyzed for a comparison with the active samplers to estimate atmospheric PAH concentrations. Pine needles were found to collect lower molecular weight (LMW) compounds far more than HiVol sampler and thus their profiles shown to compliment the HiVol …

Ab Initio Simulations Of Hydrogen And Lithium Adsorption On Silicene, Tim H. Osborn

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The energies and temperature-dependent dynamics of hydrogen and lithium chemisorption on a silicon nanosheet, called silicene, were studied using density functional theory and molecular-dynamics (MD) simulations. Silicene has a buckled honeycomb structure, and has been fabricated as suspended monolayer sheets and nanoribbons in recent experiments. We calculated the adsorption energies of hydrogen and lithium on silicene for different adsorption ratios between 3.1% and 100%. The studies will clarify the characteristics of these novel and promising nanomaterials, and pave the way for their applications.

For Hydrogen, the adsorption energy had a maximum of 3.01 eV/H for complete hydrogenation, and decreased by …

Privacy-Preserving Attribute-Based Access Control In A Grid, Sang Mork Park

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A Grid community is composed of diverse stake holders, such as data resource providers, computing resource providers, service providers, and the users of the resources and services. In traditional security systems for Grids, most of the authentication and authorization mechanisms are based on the user's identity or the user's classification information. If the authorization mechanism is based on the user's identity, fine-grained access control policies can be implemented but the scalability of the security system would be limited. If the authorization mechanism is based on the user's classification, the scalability can be improved but the fine-grained access control policies may …

Routes To Acylated Sydnones Utilizing Microwave Chemistry, Amber C. Rumple

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In the present work, microwave chemistry was utilized to improve and optimize two methods for the acylation of sydnones. Whereas before, 4-acyl-3-arylsydnones could be synthesized by the use of Friedel-Crafts reactions utilizing either Montmorillonite K-10 or bismuth(III) triflate/lithium perchlorate as catalysts in moderate to good yields after long reaction times, with the introduction of microwave chemistry 4-acyl-3-arylsydnones can be synthesized in good to excellent yields in much shorter times. A previous method using Montmorillonite K-10 allowed for a variety of 4-acetyl-3-arylsydnones to be synthesized thermally in moderate to good yields after at least 24 hours. This method was extended in …

Proximity And Thickness Estimation Of Aluminum 3003 Alloy Metal Sheets Using Multi-Frequency Eddy Current Sensor, Sunil S. Kamanalu

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The research work is focused on conducting a feasibility study on a new "non-contact" single probe dual coil inductive sensor for sensing the proximity and thickness of Aluminum (Al) 3003 alloy metal sheets, which is a non-magnetic metal. A bulk of the research and development work has already been done in the area of non-destructive testing (NDT) using eddy current technology targeted to various applications like corrosion detection, material thickness, material conductivity, etc. The research work presented in this thesis uses the prior research and development work completed in NDT as a platform for conducting this study to estimate proximity …

Respiratory-Gated Imrt Quality Assurance With Motion In Two Dimensions, Michael Todd Massie

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Intensity modulated radiation therapy (IMRT) plans can be further customized to each patient with the use of a four-dimensional (4D) respiratorygated computed tomography (CT), with time being the fourth dimension. The 4D respiratory-gated CT allows for the internal margin (IM), the expansion of the tumor volume that accounts for physiologic motions, to be addressed in the treatment planning process and no longer assumes that the treatments will be delivered to a fixed or rigid patient anatomy. Delivering the IMRT plan with a gated technique limits the treatment to a duty cycle when the target motion is at a minimum.

The …

A Contrast Pattern Based Clustering Algorithm For Categorical Data, Neil Koberlein Fore

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The data clustering problem has received much attention in the data mining, machine learning, and pattern recognition communities over a long period of time. Many previous approaches to solving this problem require the use of a distance function. However, since clustering is highly explorative and is usually performed on data which are rather new, it is debatable whether users can provide good distance functions for the data. This thesis proposes a Contrast Pattern based Clustering (CPC) algorithm to construct clusters without a distance function, by focusing on the quality and diversity/richness of contrast patterns that contrast the clusters in a …

Biodegradation Of Groundwater Pollutants (Chlorinated Hydrocarbons) In Vegetated Wetlands: Role Of Aerobic Microbes Naturally Associated With Roots Of Common Plants, Christina Lynn Powell

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Chlorinated aliphatic hydrocarbons (CAHs) are often found as groundwater contaminants because of past industrial activities and disposal practices. CAHs pose a threat to human health and thus, create a need to find both natural and engineered processes that can remove these chlorinated compounds from the environment. Natural attenuation by oxidative biodegradation is especially important because it can allow for mineralization to carbon dioxide, a nontoxic end-product. The goal of this research was to evaluate the potential oxidative biodegradation of CAHs by microorganisms that are naturally associated with wetland plant roots. The research was divided into field work and laboratory batch …

Fabrication Of Zinc Oxide Thin Films For Renewable Energy And Sensor Applications, Theresa Y. Hill

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Progress in commercializing renewable energy technologies is being advanced by developments in Zinc Oxide material science. The photovoltaic cell, for example, generates electricity by receiving solar energy into the cell, generating electrons, and simultaneously transporting electrical charge out of the cell. Metals are capable of removing electrical charge but block transmission of sunshine. Glass and plastics are capable of transmitting sunshine but block the removal of electrical charge. Therefore an exterior layer that is both optically transparent and electrically conductive is desirable. Transparent conductive oxides (TCOs) are the ideal material for such applications since they are capable of both functions. …

Dimethylmercury Production In Freshwater Sediments, David C. Kelly

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Dimethylmercury (DMHg) has been examined almost exclusively in marine environments to date, plays an uncertain role in the global cycling of Hg, and is produced by a currently unknown mechanism in natural systems. We examined DMHg production in microcosms containing 100 cm3 of freshwater sediment sampled from 3 wetlands and a lake near Dayton, Ohio. DMHg was produced from all sediments analyzed, and found that production is increased significantly by the addition of inorganic Hg from ~0.1pM to ~10pM, its production is unaffected by autoclaving the sediment, and organic carbon additions had no discernible effect on production. Its total concentrations …

Temperature And Frequency Dependent Conduction Mechanisms Within Bulk Carbon Nanotube Materials, John Simmons Bulmer

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The resistance of three types of bulk carbon nanotube (CNT) materials (floating catalyst CNT yarn, forest grown CNT yarn, and super acid spun CNT fiber) was measured from room temperature to 900 C. Fitting the curves to established conduction equations for disordered materials, competing conduction mechanisms pertaining to the material could be determined. Floating catalyst CNT yarn displayed both semiconductive and metallic isotropic behavior with a resistance minimum, similar to the behavior of crystalline graphite. It was found that, at room temperature, the semiconducting contribution-most likely junctions between CNTs-accounted for 99.99% of the overall resistance. The resistance of forest grown …

Small Molecule Caspase Inhibitors Using Isatin And Oxindole Scaffolds And A Combinatorial Approach, Hagar Mahmoud Abdallah

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Quinolyl-valyl-O-methylaspartyl-[2,6-difluorophenoxy]-methyl ketone (Q-VD-OPh) is a next generation broad spectrum caspase inhibitor, the effectiveness and reduced toxicity of which can be partially attributable to the carboxyterminal O-phenoxy group as well as the amino terminal quinolyl groups. We seek to incorporate some of these unique recognition elements onto small molecule derived protease inhibitors with drug like properties. Specifically, heterocyclic scaffolds such as isatins and oxindoles. Thus, isatins bearing electron withdrawing groups on C-5 and 2,6-difluorobenzyl moieties have been prepared by analogy to the well studied N-substituted 5-pyrrololidinylsulfonyl isatins. Moreover, 3-benzylidene oxindole derivatives bearing these structural motifs have also been prepared and their …

Visualization Of Complex Unsteady 3d Flow: Flowing Seed Points And Dynamically Evolving Seed Curves With Applications To Vortex Visualization In Cfd Simulations Of Ultra Low Reynolds Number Insect Flight, Christopher M. Koehler

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Three dimensional integration-based geometric visualization is a very powerful tool for analyzing flow phenomena in time dependent vector fields. Streamlines in particular have many perceptual benefits due to their ability to provide a snapshot of the vectors near key features of complex 3D flows at any instant in time. However, streamlines do not lend themselves well to animation. Subtle changes in the vector field at each time step lead to increasingly large changes between streamlines with the same seed point the longer they are integrated. Path lines, which show particle trajectories over time suffer from similar problems when attempting to …

Thermal And Electrochemical Characterization Of Cathode Materials For High Temperature Lithium-Ion Batteries In Ionic Liquids, Jodie R. Shoaf

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Finding a cathode material to operate a high-temperature Li-ion battery in the presence of an ionic liquid has become an attractive area of research. Three cathode materials, LiCoO2, Li4Ti5O12, and LiFePO4, were received from Electrochemical Systems Inc. of Knoxville, TN. Three ionic liquids were synthesized using a 1-alkyl-3-methylimidazolium (XMI+) cation, where the alkyl group was either ethyl, pentyl or hexyl, and contained a bis(pentafluoroethylsulfonyl)imide (Beti-) anion. The thermal and electrochemical properties of each ionic liquid, of each cathode material, and each combination of cathode material in the presence of ionic liquid were studied. All of the ionic liquids were found …

Algorithmic Techniques Employed In The Quantification And Characterization Of Nuclear Magnetic Resonance Spectroscopic Data, Paul Edward Anderson

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Nuclear magnetic resonance (NMR) based metabolomics is a developing research field with broad applicability, including the identification of biomarkers associated with pathophysiologic changes, sample classification based on the mechanism of toxicity, and clinical diagnosis. Intrinsic to these applications is the need for statistical and computational techniques to facilitate the associated data analysis. Further, a typical 1H NMR spectrum of pure proteins, biofluids, or tissue may contain thousands of resonances (i.e., peaks), thus, a pure visual inspection is insufficient to fully utilize the spectral information.

Common practice within the NMR-based metabolomics community is to evaluate and validate novel algorithms on empirical …

Crustacean Endocrine Disruption Through A Pathway Involving Nuclear Receptors, Cyclic Nucleotides And Calcium Transporters, Laxminath Tumburu

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Endocrine disruption is a complex phenomenon in the sense that endocrine disrupting chemicals (EDCs) are known to act via multiple modes of action, but the mechanisms of actions are poorly understood. In crustaceans, calcium (Ca²⁺) apart from its role as a second messenger, is also a major constituent of the calcified exoskeleton which undergoes a periodic mineralization/demineralization process known as the molting cycle. Molt cycle is under the control of steroid hormones, ecdysteroids. EDCs disrupt this molting process via their interference with receptor-mediated ecdysteroid signaling. However, the hormonal regulation of Ca²⁺ flux in crustacean molting is poorly …

Atmospheric Effects On The Propagation Of Mmw And Sub-Mmw Radiation, John S. Cetnar

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This thesis is a study of the propagation of millimeter wavelength (MMW) and submillimeter wavelength (sub-MMW) electromagnetic radiation (a.k.a. THz radiation) through the Earth's atmosphere. THz radiation is electromagnetic radiation that exists between the microwave and far infrared regions of the electromagnetic spectrum. It is nonionizing radiation but can penetrate through materials that are opaque to visible light so therefore has many new and useful applications. Unfortunately, THz radiation is heavily attenuated by the Earth's atmosphere as it propagates through it. This therefore represents a challenge to communications and sensing applications at millimeter and sub-millimeter wavelengths. In this work, the …

Towards The Total Synthesis Of Haplomyrtin, Nora Ellen Hunter

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Haplomyrtin, a 1-aryl-2,3-naphthalide lignan obtained from Turkish Haplophyllum myrtifolium and Haplophyllum telephioides offers a number of synthetic challenges with the incorporation of two aromatic hydroxyl groups at positions C4 and C7 on the naphthalene ring system and regiospecific condensation of the γ-lactone ring. Improvements towards the total synthesis of haplomyrtin were pursued with commercially available vanillin and piperonal in a total of 8 separate steps. All steps have excellent reproducibility. This strategy includes bromination of protected vanillin to yield 2-(4-(4-methoxybenzyloxy)-2-bromo-5-methoxyphenyl)-1,3-dioxolane and 2-(4-(benzyloxy)-2-bromo-5-methoxyphenyl)-1, 3-dioxolane in 48% and 88% yield respectively, and incorporation of the fully functionalized pendant aryl ring through a …

Surveillance In A Smart Home Environment, Ryan Stewart Patrick

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A system for assisting the elderly in maintaining independent living is currently being designed. When mature, it is expected that this system will have the ability to track objects that a resident may lose periodically, detect falls within the home, and alert family members or health care professionals to abnormal behaviors.

This thesis addresses the early stages of this system's development. It presents a survey of the work that has previously been completed in the area of surveillance within a home environment, information on the physical characteristics of the system that is being designed, early results related to this system, …

Mercury Speciation In Temperate Tree Foliage, Melissa Danielle Tabatchnick

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Cycling of mercury (Hg) and monomethylmercury (MMHg) in forest ecosystems can affect exposures of terrestrial and aquatic wildlife within the watershed. Litterfall has been posited to be a major source of MMHg and total Hg to the forest floor; however, the origin of MMHg associated with tree foliage is largely unknown. I tested the hypothesis that leaf MMHg would be controlled by root uptake and thereby proportional to levels in soil. Fresh leaves and associated soil samples were sampled from nine tree species (deciduous and coniferous) at 30 locations spanning a 1145 km2 area in southwest Ohio, a region presumed …

Prognosis: A Wearable System For Health Monitoring Of People At Risk, Alexandros A. Pantelopoulos

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Wearable Health Monitoring Systems (WHMS) have drawn a lot of attention from the research community and the industry during the last decade. The development of such systems has been motivated mainly by increasing healthcare costs and by the fact that the world population is ageing. In addition to that, RandD in WHMS has been propelled by recent technological advances in miniature bio-sensing devices, smart textiles, microelectronics and wireless communications techniques. These portable health systems can comprise various types of small physiological sensors, which enable continuous monitoring of a variety of human vital signs and other physiological parameters such as heart …

The Derivation And Testing Of Three-Dimensional Line Equations That Predict The Location Of Brachytherapy Sources, Rhett Ellis Lindsey

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In High Dose Rate brachytherapy, a catheter is placed inside the body and a radioactive source is allowed to dwell at specific positions to treat a tumor. In normal usage, anatomical images acquired before the treatment are used to plan dwell positions, and then the plan is executed without further verifying source locations during treatment. However, slight errors in catheter positioning and shifts in internal anatomy cause variations in source position. In this study, a general method for determining dwell positions during treatment is evaluated. For this method, the treatment source exposes the tumor to radiation and creates an image …

Dosimetric Effects Near Implanted Vascular Access Ports Under External Electron Beam Radiation, David Coll Segarra

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Previous studies on dosimetry show important effects for metal vascular access ports for x-rays and electron beams and moderate to no effects for plastic ports for x-ray beams when ports are in the path of the beam. No previous studies exist regarding the effects of electron beams on vascular access ports other than for those made of metal although it has been suggested that electron beam attenuation through non-metal ports may be possible.

Measurements of relative ionization through the device and adjacent to the device anteriorly and laterally were taken. A clinical particle accelerator delivered typical clinical electron beams of …

Routes To Sydno[3,4-A]Quinoxalines, Erik Dihrkop

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In the present work, the reactivity of alkyl and aryl sydnoquinoxalines was studied. Using a previously developed method, triphenylphosphine-2-(3-sydnonyl)phenylimide was prepared in a two-step process via a diazotization / azidation process of 3-(2-aminophenyl)sydnone, followed by treatment with triphenylphosphine. Due to the inability to achieve previously reported yields, a new, one-step method using Mitsunobu conditions was employed to synthesize the iminophosphorane in a good yield. A similar, brominated iminophosphorane was synthesized using the same conditions in a good yield. Treatment of both the brominated and non-brominated iminophosphoranes with alkyl and aryl isocyanates or isothiocyanates in an aza-Wittig process, gave the corresponding …

Conversion Of Carbon Dioxide And Hydrogen Into Methane In Bench-Scale Microcosms And Packed Column Reactors, Brian Alexander Congiu

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Escalating energy demands, rising costs, and increasing awareness of the environmental impacts of current energy sources have created an immediate need for sustainable, alternative energy resources and innovative fuel technologies. It is believed that a potential carbon-neutral fuel source can be generated through the microbial production of methane gas by methanogenic archaea. Carbon dioxide captured from the atmosphere and renewable production of hydrogen can be used to support these microorganisms for the large-scale production of methane. Bench-scale investigations involving 160 mL serum bottle batch experiments and two 11L packed-column reactors were conducted to evaluate the feasibility and efficiency of microbial …

Evolution And Analysis Of Neuromorphic Flapping-Wing Flight Controllers, Sanjay Kumar Boddhu

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The control of insect-sized flapping-wing micro air vehicles is attracting increasing interest. Solution of the problem requires construction of a controller that is physically small, extremely power efficient, and capable. In addition, process variation in the creation of very small wings and armatures as well as the potential for accumulating damage and wear over the course of a vehicle's lifetime suggest that controllers be able to self-adapt to the specific and possibly changing nature of the vehicles in which they are embedded. Previous work with Evolvable Hardware Continuous Time Recurrent Neural Networks (CTRNNs) as applied to adaptive control of walking …