Physical Sciences and Mathematics Commons^™

Studies Of Polymers In Fouling Release Coating Science, Haoran Chen

Master's Theses and Doctoral Dissertations

In chapter one, we describe our studies of the solubility properties of two biocides in F127 aqueous solutions. One is zinc omadine and the other is C9211. The partition coefficients of these two biocides were also determined from the analytical results.

In chapter two, we conducted phase related studies of a triblock copolymer, PEO400- PBO55-PEO400 in aqueous solution. The phase diagram features of PEO400-PBO55-PEO400 in water are compared with those of F127. We believe the lack of a lower gel to liquid transition boundary in this system is because of the relatively longer PEO segments relative to the PBO segment. …

Laser Surface Thermal Lensing (Stl): An Optical Method For Surface Analysis Of Glass Transition Effects In Transparent Polymers, Nandita Prasad

Master's Theses and Doctoral Dissertations

Absorption of energy from a modulated laser beam by a transparent substrate leads to cyclic thermal expansion and contraction of the surface at the pump beam focus. This minute distortion of the surface forms a transient optical lens structure, which can be monitored by the changes it induces in a second laser beam reflected at an angle off the same focal point. The Surface Thermal Lensing (STL) technique is based on detecting the modulated interference pattern that results from interaction of the probe beam wavefront as it reflects from both the flat surface surrounding the transient lens and the curved …

Adding Simple Simulations To Video Games To Improve Realism, Leonard Kinnaird-Heether

Master's Theses and Doctoral Dissertations

In this paper a method of enhancing the realism of certain computer game types, particularly First Person Shooter games, is explored by attempting to include intelligent neutral background characters to the game environment. This method also requires that the inclusion of these background characters will not adversely affect the performance of a game by drastically increasing the computational complexity of the game. A simulation was created to show how this can be done using a group of intelligent agents based in a simulated world, and a simplified system of norms designed to influence the agents’ behavior. The agents are designed …

Synthesis And Dye Leakage Assay Of Human And Rat Islet Amyloid Polypeptide 10-19 And Insulin 14-18, Andrew William Gray

Master's Theses and Doctoral Dissertations

Islet amylin polypeptide (IAPP) is co-secreted along with insulin in the pancreatic islets of Langerhans. During type 2 diabetes mellitus, human IAPP (hIAPP) fibrilizes to form amyloid deposits that are found post-mortem in more than 95% of people with the disease. Rodents do not suffer from type 2 diabetes mellitus as their IAPP (rIAPP) does not undergo self-aggregation. Although the amyloid deposit is found in those with the disease, the actual cause of the disease is the cytotoxicity of the mechanism that forms those amyloid deposits. The self-aggregation of IAPP to form amyloid deposits is inhibited by insulin due to …

The Development Of A Novel And Potentially Nondestructive Pretreatment For The Radiocarbon Dating Of Archaeological Artifacts, Mary Ellen Ellis

Master's Theses and Doctoral Dissertations

Because the traditional acid-alkali-acid method for pretreating archaeological artifacts prior to radiocarbon dating is destructive to most materials, the possibility of developing an alternative pretreatment is important to preserving culturally- and historically-significant artifacts. The alkali step usually involves a 1M or higher concentration NaOH wash to remove humic acid contamination. The purpose of this work is to replace the alkali step with an equally effective, yet less harsh treatment. Charcoal soaked in a humic acid standard was used to mimic a contaminated artifact. Residues from treatments with NaOH, phosphate buffer (pH 8), and deionized water were characterized using THM-GC-MS. Preliminary …

Studying Scratching/Buffing Mechanism Of The Clearcoats And Improving The Technique And Devices/Materials In Automobile Refinish Work, Chakravarthi Mallikarjun Nagolu

Master's Theses and Doctoral Dissertations

As automotive coating technology advances, the manufacturers have developed new generations of after-market coatings as well as OEM (Original Equipment Manufacturing) coatings. The new coatings possess much stronger mar/scratch resistance either with raised elastic modulus and hardness or with the ability of self-healing. These pose new challenges to the auto-body refinish work. In the refinishing process, the after-market coatings are applied to the bodies (surfaces), and then the imperfections, which are inevitable during the application process due to the environmental dust in the shops, will be buffed out to make a smooth and shining surface. The new coatings are very …

Design And Synthesis Of Small-Molecule Inhibitors As Anti-Malarial And Anti-Serpin Agents, Maria Mirela Puscau

Master's Theses and Doctoral Dissertations

This work describe the design, synthesis and evaluation of small-molecule inhibitors of two different biological targets: Plasmodium falciparium, the most virulent malarial parasite in humans, and plasminogen activator inhibitor-1 (PAI-1), an endogenous serine proteases inhibitor implicated in a wide range of biological processes. Malaria is one of the top global health threats, and there is a great need for developing effective new chemotherapies. PAI-1 is a major component in the regulation of the plasminogen activation system, and the overexpression of this protein has been implicated in a number of conditions, such as thrombosis, atherosclerosis, and myocardial infarction. The research …

Muir Studies Of Nonlinear Ionospheric Interactions At Haarp, Margaret Eileen Bacon

Master's Theses and Doctoral Dissertations

Studies of nonlinear ionospheric interactions were undertaken at the High Frequency Active Auroral Research Program (HAARP) site in Alaska using the co-located Modular UHF Incoherent scatter Radar (MUIR). High frequency heating of the ionosphere produced plasma wave decay processes, the signatures of which were received by MUIR and interpreted with spectral analysis in MATLAB. The most commonly observed decay scheme was that of the Parametric Decay Instability, producing the distinct multifrequency cascade feature in the HF backscatter. The results presented here are intended to contribute to the understanding of HF heating facility capabilities, plasma wave decay processes, and diagnostic instrument …

Application Of Impedance Spectroscopy To The Study Of Dithiocarbamate Species On Au Surfaces: Effects Of Aqueous Cu²⁺ And Mg²⁺ Ions, Tom Riha

Master's Theses and Doctoral Dissertations

Self-assembled monolayers (SAM) of dithiocarbamate ligands were formed on the Au surface of an interdigitated electrode (IDE) array by reaction of amines with CS₂ in H₂O/CH₃OH solutions. Impedance spectroscopy was used to probe for the presence of each SAM as they were individually applied to the surface of the IDE by examining differences in collected impedance data after each step of the chemical application sequence. The impedance behavior of the SAM’s were then studied in the presence of aqueous Cu²⁺ and Mg2+ ions. A treated IDE array would, in theory, be able to preferentially …

Application Of Surface Thermal Lens Technology Combined With Polarization To The Study Of Polymers, Daeha Joung

Master's Theses and Doctoral Dissertations

A new approach was attempted to investigate the characteristics of polymers by using photothermal technology. The Surface Thermal Lens (STL) technique was employed to study polymers because of its higher spatial resolution and greater sensitivity than the classical photothermal detection techniques (PDT). Zeonex [Cyclo-Olefin-Polymer] and acrylic [Poly–Methyl- Meth-Acrylate] were used as the samples. Polarization was applied to the STL technique. The signals of Zeonex were different from those of acrylic when the STL probe beam was polarized. Two different polarizer orientations for the probe beam, crossed and parallel, were used to observe the STL signal response to the samples. No …