Physical Sciences and Mathematics Commons^™

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 …

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 …

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 …

Transport Through Georeservoirs: Spatial Entropy In Hydraulic Properties, And Temporal Entropy In Residence Time Distributions, Lumeng Huang

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The general principle of maximum entropy can be used to guide the construction of flow and transport models parameters when are uncertain. The principle states that the model which maximizes the entropy should be chosen so that the full multiplicity or uncertainty is represented in the model outcomes.

In models for flow and transport through georeservoirs, the principle would commonly be applicable to the uncertainty in the model outcome for the time of travel through the system, in order to represent the full range of multiplicity in the distribution of residence times. Importantly, the model which maximizes the entropy in …

Sulfur-Tolerant Catalyst For The Solid Oxide Fuel Cell, Bozeman Joe Frank Iii

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JP-8 fuel is easily accessible, transportable, and has hydrogen content essential to solid oxide fuel cell (SOFC) operation. However, this syngas has sulfur content which results in a poisonous hydrogen sulfide that degrades electrochemical activity and causes complete SOFC failure in some cases. The goal is to synthesize and verify a cost-effective, catalyst supported on cerium oxide that either stabilizes ionic conductivity in the presence of hydrogen sulfide and/or is highly sulfur-resistant. After thorough computational analysis, it was concluded that the platinum-copper skin catalyst was the most cost-effective, sulfur-resistant catalyst. Experimental synthesis of copper, platinum, and platinum-copper skin catalysts supported …

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 …

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 …

Novel Synthesis Of Polyhydrogenated Fullerenes, Angela Campo

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Hydrogenated fullerenes are of interest as a starting material in metal fulleride synthesis. By reacting C₆₀H₂ with various metals, alloyed metal fullerides could be produced. To achieve this goal, first a reliable synthesis of C₆₀H₂ must be determined. C₆₀H₂ is difficult to synthesis exclusively; C₆₀H₄ and C₆₀H₆ are also produced. Reduction of C₆₀ with NaBH₄ produced a mixture of products as well as excessive unreacted C₆₀. Attempts to modify this reaction to achieve C₆₀H₂ exclusively were unsuccessful. A …

Synthesis And Reactivity Of Alpha-Azido Acylals, Gretchen Bell

Honors Theses

alpha-Azido -Azido acylals are a novel combination of azide (N3) and acylal [R-C(OOCR)2] functional groups. Since these compounds are new chemical entities, little is known in the chemical literature about their physical, chemical, and biological properties. This synthetic methodology investigation sought to (1) develop a one-pot, two reaction method for preparing alpha-azido acylals and (2) investigate the chemical reactivity of alpha-azido acylals with phosphine reagents. Progress has been made and will be discussed regarding both the synthesis and reactivity of alpha-azido acylals. This work developed methods and processes that will have significant impact in our broader objective of exploring the …

Magnetocaloric Effect In Thin Films And Heterostructures, Christopher Bauer

USF Tampa Graduate Theses and Dissertations

The goals of this work are the optimization of the magnetocaloric effect in Gadolinium thin film structures. We approach this issue from two directions, that of process optimization and of interface effects. Past results showed Gd₂O₃ in our Gadolinium thin films, and the presence of such oxide seemed to grow with the temperature at which the film was grown or annealed. Comparison of samples grown without chamber gettering to those that were gettered show differences in their structural and magnetic properties, and we conclude that gettering is an effective step in enhancing the quality of Gd thin …

Thermal Imaging Of The Waccasassa Bay Preserve: Image Acquisition And Processing, Ellen A. Raabe, Elzbieta Bialkowska-Jelinska

School of Geosciences Student Publications

Thermal infrared (TIR) imagery was acquired along coastal Levy County, Florida, in March 2009 with the goal of identifying groundwater-discharge locations in Waccasassa Bay Preserve State Park (WBPSP). Groundwater discharge is thermally distinct in winter when Floridan aquifer temperature, 71-72 °F, contrasts with the surrounding cold surface waters. Calibrated imagery was analyzed to assess temperature anomalies and related thermal traces. The influence of warm Gulf water and image artifacts on small features was successfully constrained by image evaluation in three separate zones: Creeks, Bay, and Gulf. Four levels of significant water-temperature anomalies were identified, and 488 sites of interest were …

Mined-Over Matter, Judy Mcilrath

School of Geosciences Faculty and Staff Publications

No abstract provided.

Representing Synonymity In Causal Logic And In Logic Programming, Joohyung Lee, Yuliya Lierler, Vladimir Lifschitz, Fangkai Yang

Computer Science Faculty Proceedings & Presentations

We investigate the relationship between rules representing synonymity in nonmonotonic causal logic and in answer set programming. This question is of interest in connection with current work on modular languages for describing actions.

2010 File Geodatabase Containing Photo Point Locations, Aerial Photos, And Flight Maps, City Of Tampa Department Of Sanitary Sewers Bay Study Group, Pete Reehling, Richard Mckenzie

Data Sets

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the photo point locations, aerial photos, and flight maps for the year 2010.

Building An Oss Quality Estimation Model With Catreg, Athos Origin China, Luiz Fernando Capretz, Danny Ho

Electrical and Computer Engineering Publications

Open Source Software (OSS) has been a popular form in software development. In this paper, we use statistical approaches to deriveOSSquality estimation models. Our objective is to build estimation models for the number of defects with metrics at project levels. First CATREG (Categorical regression with optimal scaling) is used to obtain quantifications of the qualitative variables. Then the independent variables are validated using the stepwise linear regression. The process is repeated to acquire optimal quantifications and final regression formula. This modeling process is performed based on data from theOSScommunities and is proved to be practically valuable.

Improving Privacy And Performance In Anonymous Communications, Nayantara Mallesh

Computer Science and Engineering Dissertations

Anonymous communications systems provide an important privacy service by keeping passive eavesdroppers from linking communicating parties. However, an attacker can use long-term statistical analysis of traffic sent to and from such a system to link senders with their receivers. While it is important to protect anonymous systems against such attacks, it is also important to ensure they provide good performance. In this thesis, we aim to make contributions to both these areas.In the statistical disclosure attack (SDA), an eavesdropper isolates his attack against a single user, whom we call Alice, with the aim of exposing her set of contacts. To …

Data Analytics Over Hidden Databases, Arjun Dasgupta

Computer Science and Engineering Dissertations

Web based access to databases have become a popular method of datadelivery. A multitude of websites provides access to their proprietary datathrough web forms. In order to view this data, customers use the web forminterface and pose queries on the underlying database. These queries areexecuted and a resulting set of tuples (usually the top-k ones) is served to thecustomer. Top-k along with strict limits on querying are constraints used by thedatabase providers to conserve the power of the underlying data distribution.Delivering limited access only to tuples that satisfy a query enables providers toexpose only a small snippet of the entire …

Advanced Software Testing Techniques Based On Combinatorial Design, Wenhua Wang

Computer Science and Engineering Dissertations

Combinatorial testing refers to a testing strategy that applies the principles of combinatorial design to the domain of software test generation. Given a system with k parameters, combinatorial testing requires all the combinations involving t out of k parameters be covered at least once, where t is typically much smaller than k. The key insight behind combinatorial testing is that while the behavior of a system may be affected by many parameters, most faults are caused by interactions involving only a small number of parameters. Empirical studies have shown that combinatorial testing can dramatically reduce the number of tests while …

Reinforcement Learning Based Strategies For Adaptive Wireless Sensor Network Management, Kunalbhai Shah

Computer Science and Engineering Dissertations

In wireless sensor networks (WSN), resource-constrained nodes are expected to operate in highly dynamic and often unattended environments. WSN applications need to cope with such dynamicity and uncertainty intrinsic in sensor networks, while simultaneously trying to achieve efficient resource utilization. A middleware framework with support for autonomous, adaptive and distributed sensor management, can simplify development of such WSN applications. We present a reinforcement learning based WSN middleware framework to enable autonomous and adaptive applications with support for efficient resource management. The uniqueness of our framework lies in using a bottom-up approach where each sensor node is responsible for its resource …

Enhancing Personalized Search And Improving Accuracy And Performance For Keyword-Based Xml Queries, Kamal Taha

Computer Science and Engineering Dissertations

This dissertation research focuses on three aspects related to querying of XML data. The three focus areas are: (1) Improving accuracy of XML keyword queries by modeling the contexts of XML elements; (2) Enhancing XML-based personalized search by using group profiling to determine individual preferences; and (3) Improving performance of distributed XML querying by caching of frequently-used query results. For each of these three focus areas, we developed formal concepts and algorithms that lead to the improved accuracy and performance. Our contributions are as follows:1. Improving the accuracy of XML keyword queries:We improve search accuracy by utilizing nodes' contexts in …

Growth And Toxicity Of Prymnesium Parvum In Long-Term Cultures At Low Temperature And Salinity, Xianzi He

Earth & Environmental Sciences Theses

There is a paradox reported concerning observations of toxic blooms of Prymnesium parvum in winter in Texas (USA), and its growth performance in the laboratlry. Culture experiments indicate relatively high optimum temperature and salinity for growth, conditions different from those ofwinter in Texas. Because previous laboratory experiments were of short duration, it was suggested that long-term culturing of many generations could allow physiological and epigenetic changes, as well as natural selection to take place, leading to improved growth performance at low temperature and salinity. In this study, the growth and toxicity of P. parvum was investigated under relatively low temperature …

Electrowetting Of Ionic Liquids And Development Of An Electrowetting Based Tunable Rc Filter And Its Uses As An Analytical Detector, Yasith Sameera Nanayakkara

Chemistry & Biochemistry Dissertations

Wettability control of a liquid drop by an external electric field or "electrowet- ting" recently was the subject of special interest among researchers due to its util- ity for a variety of applications. Some of these include "electrowetting on dielectric (EWOD)" based digital microfluidic lab-on-a-chip devices, EWOD lenses and EWOD displays. In these EWOD based devices, water or aqueous electrolytes are used as the liquid medium. However, the use of water or aqueous electrolytes has several limitations and may reduce the efficiency as well as accuracy of these devices. Low thermal stability, evaporation, fouling and fixed phys- iochemical properties are …

Nanopore Stochastic Sensing With Ionic Liquid Supporting Electrolyte And Ionic Liquid Based Water Quantitation Using Gas Chromatography, Dilani A. Jayawardhana

Chemistry & Biochemistry Dissertations

This dissertation focuses toward finding two new avenues to explore the properties of ionic liquids (ILs). First, ILs has been used as a novel, and advantageous supporting electrolytes in nanopore stochastic sensing technology. Here, the sensing element is the alpha hemolysin protein, while a solution containing an ionic liquid will be used as the background electrolyte, instead of the typical used NaCl/KCl solution. This method employs single-channel recording with the planar lipid bilayer technique, where current modulation represents individual binding events. In this study, a useful means of implementing IL salt solutions will be demonstrated. Specifically, its great enhancements of …

Estrogen Analysis By Liquid Chromatography - Mass Spectrometry, Hien P. Nguyen

Chemistry & Biochemistry Dissertations

Estrogens are well known as female hormones associated with both health and disease. Although they have been reported as potential carcinogens, their use as therapy in the treatment of neurodegeneration has recently received a great deal of attention. The main goal of this work was to advance estrogen analysis using liquid chromatography - mass spectrometry (LC-MS) and associated techniques in order to support pre-clinical and clinical research on the neuroprotective effects of estrogens. Native estrogen analyses were performed in different types of biological samples, including human cerebrospinal fluid (CSF), horse serum, phosphate buffered saline - bovine serum albumin (PBS-BSA), mouse …

Total Synthesis Of Cyclooroidin And Studies Towards Some Oroidin Dimers, Sabuj Mukherjee

Chemistry & Biochemistry Dissertations

This dissertation consists of two parts. The first part describes the synthesis of northern fragment of nagelamide R and the enantioselective total synthesis of cyclooroidin. The oroidin family of marine natural products is a growing group of marine sponge-derived alkaloids which contain 2-aminoimidazole and pyrrolecarboxamide fragments as their signature features. The structural complexity, and in many cases interesting biological profiles, of these compounds has rendered several of these natural products as targets of interest. In the context of nagelamide R, the key transformation involves the intramolecular cyclization of a pyrrolecarboxamide via the carbonyl oxygen leading to the formation of oxazoline, …

Analytical Characterization Of Anthocyanins From Natural Products By Reverse-Phase Liquid Chromatography-Photodiode Array-Electrospray Ionization-Ion Trap-Time Of Flight Mass Spectrometry, Jeremy S. Barnes

Chemistry & Biochemistry Theses

Anthocyanins are known to be one of the most powerful phytochemical antioxidant and believed to have a positive influence on a variety of health conditions. Numerous studies continue on these compounds that are readily found in most plants. Red hybrid-tea rose petals and wild blueberries were used as model systems for optimizing the extraction and identification process of anthocyanins in plant material using high performance liquid chromatography (HPLC) and mass spectrometry (MS) without the use of authentic standards. A number of extraction parameters, including sample homogenization, solvent selection and acid type and amount, were varied to examine the effects on …

Ontology-Driven Discovery Of Scientific Computational Entities, Pearl W. Brazier

Open Access Theses & Dissertations

Many geoscientists use modern computational resources, such as software applications, Web services, scientific workflows and datasets that are readily available on the Internet, to support their research and many common tasks. These resources are often shared via human contact and sometimes stored in data portals; however, they are not necessarily available for metadata annotations that can assist in collaborative research or machine processing. Scientists' knowledge of their resources and processes are at risk of being lost. A scientist-driven discovery environment, which assumes a level of technical expertise generally possessed by a geoscientist, is needed to enable discovery and comparisons of …

Bagc.M: Three Dimensional Gravity Modeling Software With An Application In Death Valley, Ca, Brian Eugene Eslick

Open Access Theses & Dissertations

Basin Anomaly Gravity Calculator (BAGC.m) is a 3D interactive gravity modeling package designed to create, edit, and calculate the gravitational attraction of basin models entirely within the MATLABTM environment. Gravity anomalies are calculated using the Rectangular Prism Method (Bott, 1960; Kane, 1962; and Plouff, 1966) which subdivides earth models into regularly spaced rectangular prisms. This approach requires large 3D matrices to store most realistic earth models. The process of model editing is simplified by storing basins as 2D gridded files which define the depth to the boundary between basement rock and sedimentary fill for each model cell. In order to …

Titanium Niobium Nano Porous Materials: New Photocatalysts For Water Decontamination, Maryam Zarei Chaleshtori

Open Access Theses & Dissertations

Water pollution is major environmental problem worldwide. Many common industrial organic compounds that make their way into water systems can be carcinogenic at trace levels and are difficult and costly to remove completely with conventional technologies. Because of this, authorities and researchers are trying to improve current water cleanup techniques.

Heterogeneous photocatalysts that accelerate the photocatalytic destruction of organic contaminants in water are a potentially inexpensive and highly effective way to remove both trace-level and saturated harmful compounds from industrial waste streams and drinking water. Titanium dioxide has the potential to completely mineralize organic compounds in water under ultraviolet light. …

Hydrological Characteristics Of A Large-Scale Flooding And Draining Experiment, Barrow, Alaska, Edith Jaurrieta De Velasco

Open Access Theses & Dissertations

The Arctic appears to be affected by climate change more so than any other region on Earth. Some of the most significant climate change impacts reported for the Arctic are associated with dramatic shifts in the hydrologic regime of terrestrial ecosystems. Understanding the hydrologic processes that are associated with different components of arctic terrestrial ecosystems is important because water in the form of snow or rain influences a range of properties and processes such as land-atmosphere energy and trace gas fluxes, nutrient cycling, ecosystem dynamics, biodiversity, periglacial processes and surface albedo. Furthermore, plants, animals, and native people of the Arctic …