Physical Sciences and Mathematics Commons^™

Estimating Permeability From The Grain-Size Distributions Of Natural Sediment, Lawrence Mastera

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Permeability, k, can be estimated using the Kozeny-Carman equation, given a grain-size distribution with any number of grain-size categories and the porosity of a sediment. A recursive method was developed to calculate the effective grain-size parameter, d, for sediment mixtures with more than three grain sizes. The method was tested on four sediment models of sand, gravelly sand, sandy gravel, and open-framework gravel created from grain-size distributions. The k estimated from the recursive method were consistent with physical measurements of k.

Determining Metastable Densities In An Argon Discharge Through Optical Emission Spectroscopy, Jared A. Miles

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A plasma diagnostic technique has been experimentally demonstrated where optical emission measurements of relative intensities of spectral lines in the violet range were combined with available electron-impact cross sections to yield absolute Ar metastable species concentration. An enabling factor of this analysis was that the electron excitation pattern was quite different between the Ar ground state and the metastable state. The result of this pattern was that the optical spectrum was unique depending on whether the emission was generated by direct excitation from the ground state, or by stepwise excitation from one of the metastable states. This study has shown …

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 …

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 …

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 …

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 …

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 …

Functionalized, Semicrystalline Poly(Ether Ketone)S Via In Situ Modification Chemistry, Raghavendhar Reddy Kotha

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AB3 monomer (3,4,5-Trifluoro-4'-hydroxybenzophenone) was used for polymerizations in order to mimic the combination of AB and AB2 monomers, and which has potential to facilitate concurrent polymerization and functionalization. 'Pre' and 'post' polymerization functionalization of the PEK system was done using phenol, 4-bromophenol, and 3/4-aminophenol. The solubility of the functionalized polymers was increased; and the crystallinity was decreased significantly compared to the corresponding unfunctionalized homopolymer. The polymers were characterized by 1H and 13C NMR spectroscopy, Gel Permeation Chromatography (GPC), Thermogravimetric Analysis (TGA), and Differential Scanning Calorimetry (DSC). DSC results showed that the crystallinity of the polymer was tuned by the amount …

How The Growth Of The Frampton Fold Affected The Growth Of The Green Knoll Diapir, John A. Zinck

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The growth of structural features formed by the movement of the Louann Salt within the study area follows a fold-first model (Rowan et al., 2000), in which the formation of the Frampton Fold predates the formation of the Green Knoll Diapir. The Frampton Fold was formed during two growth episodes driven by movement of the Louann Salt within the study area. The folding and faulting resulting from these growth episodes created a conduit through which the autochthonous Louann Salt was extruded to the sea floor during the Pliocene. Following a depositional episode consisting of the early sequences of the Mississippi …

Estimating Evapotranspiration Using Remote Sensing: A Hybrid Approach Between Modis Derived Enhanced Vegetation Index, Bowen Ratio System, And Ground Based Micro-Meteorological Data, Sumantra Chatterjee

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We investigated water loss by evapotranspiration (ET) from the Palo Verde Irrigation District (PVID) and the Cibola National Wildlife Refuge (CNWR) in southern California bordering the Colorado River collaborating with the United States Bureau of Reclamation (U.S.B.R.). We developed an empirical model to estimate ET for the entire PVID using satellite derived MODIS enhanced vegetation index (EVI), and ground based measurements of solar radiation and vapor pressure. We compared our predictions with U.S.B.R. estimates through statistical cross validation and showed they agree with an error less than 8%. We tested the same model for an alfalfa field inside PVID to …

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 …

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, …

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 …

1-Alkyl-3-Methylimidazolium Bis(Trifluoromethylsulfonyl)Imide Based Ionic Liquids: A Study Of Their Physical And Electrochemical Properties, Charles William Dutton

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Ionic liquids are of interest because of their electrochemical and thermal properties and their possible use as electrolytes in batteries. In this work five ionic liquids were synthesized. They consisted of a 1-alkyl-3-methylimidazolium (RMI⁺) cation, where the alkyl group was ethyl, propyl, butyl, pentyl, or hexyl, and a bis(tri-fluoromethylsulfonyl)imide (NTf2^-)anion. The decomposition temperatures, melting points, conductivities, viscosities, densities, absorption and desorption of water, diffusion coefficients, and electrochemical properties were studied. It was found that these ionic liquids were thermally stable up to ~310 °C, and that EMINTf₂ had a melting point at -18.26 °C. Conductivities …

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 …

Electrochemical Deposition Of Molybdenum And Tungsten From Trinuclear Metal Clusters (M3O2(Oac)6(H2O)3(Cf3So3)2) In 1-Ethyl-3-Methylimidazolium Tetrafluoroborate Ionic, Charles Woods

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Electrochemical properties of Mo₂WO₂(O₂CCH₃)₆(H₂O)₃(CF₃SO₃)₂ and W₃O₂(O₂CCH₃)₆(H₂O)₃(CF₃SO₃)₂ clusters in 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIBF₄) ionic liquid was investigated. Cyclic voltammograms using a platinum electrode indicated that deposition of metal had occurred. Constant potential electrolysis of Mo₂WO₂(O₂CCH₃)₆(H₂O)₃(CF₃SO₃)₂ at -1.9 V using a platinum foil electrode …

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 …

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 …

Trace Metal Fluxes In Southwest Ohio Watersheds, Avani Naik

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Land-use and watershed characteristics affect the cycling and transport of trace metals in rivers. I investigated the influence of different land uses and water physicochemistry on loadings, partitioning, and speciation of Hg, Zn, Cr, Ni, V, Cd, Cu, and Pb in three contrasting watersheds near the Dayton, Ohio metropolitan area over a 13-month period; Wolf Creek (urban/residential), Holes Creek (urban/residential), and Little Miami River (agricultural). Metal concentrations were related positively to discharge in each stream. Dissolved organic ligands appear to influence trace-metal partitioning between filtered and particle phases, however, particle-associated metals were dominant in each site. Total Hg concentrations and …

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 …

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 …