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Full-Text Articles in Physical Sciences and Mathematics

Ultra-Stable Protein-Polymer Bioconjugates, Kyle S. Cole Dec 2012

Ultra-Stable Protein-Polymer Bioconjugates, Kyle S. Cole

Master's Theses

No abstract provided.


The Effects Of Color Concentrates On The Rheology Of Tint Bases, Doug James Herrick Dec 2012

The Effects Of Color Concentrates On The Rheology Of Tint Bases, Doug James Herrick

Master's Theses

ABSTRACT

THE EFFECTS OF COLOR CONCENTRATES ON THE RHEOLOGY OF TINT BASES

Douglas James Herrick

Waterborne coatings are formulated with a number of different ingredients; water, latex polymers, pigments, surfactants, dispersants, defoamers, biocides, coalescing aids, and rheology modifiers or thickeners. Rheology modifiers are necessary in order to improve the physical properties of the coating before, during, and after application to a substrate. There are two kinds of rheology modifiers used in waterborne coatings; associative thickeners and non-associative thickeners. Coatings formulated with associative thickeners are quite sensitive to coating variations; the slightest change in the formulation has profound effects on the …


Controlling Nanoparticle Dispersion For Nanoscopic Self-Assembly, Nathan S. Starkweather Dec 2012

Controlling Nanoparticle Dispersion For Nanoscopic Self-Assembly, Nathan S. Starkweather

Master's Theses

Nanotechnology is the manipulation of matter and devices on the nanometer scale. Below the critical dimension length of 100nm, materials begin to display vastly different properties than their macro- or micro- scale counterparts. The exotic properties of nanomaterials may trigger the start of a new technological revolution, similar to the electronics revolution of the late 20th century. Current applications of nanotechnology primarily make use of nanoparticles in bulk, often being made into composites or mixtures. While these materials have fantastic properties, organization of nano and microstructures of nanoparticles may allow the development of novel devices with many unique properties. …


Preparation Of Nitrogen-Containing Heterocycles Via Cyclization Of Pyridine-Tethered Organolithiums, Elizabeth Archer Nov 2012

Preparation Of Nitrogen-Containing Heterocycles Via Cyclization Of Pyridine-Tethered Organolithiums, Elizabeth Archer

Master's Theses

No abstract provided.


Design And Synthesis Of Fluorescence Turn-On Probes For Iron, Randy K. Jackson Nov 2012

Design And Synthesis Of Fluorescence Turn-On Probes For Iron, Randy K. Jackson

Master's Theses

No abstract provided.


Anti-Corrosion Performance Of Primer And Top Coat Formulations For Metal Substrates, Laural Elizabeth Hargrove Sep 2012

Anti-Corrosion Performance Of Primer And Top Coat Formulations For Metal Substrates, Laural Elizabeth Hargrove

Master's Theses

This project involved the improvement of several properties of the current “universal” primer coating sold by Kelly-Moore Paint Company. This formulation is an all purpose primer used both for interior and exterior applications. However, its corrosion resistance has room for improvement. The addition of sodium nitrite, an aminocarboxylate salt, and a zinc phosphate-based additive were all tested as corrosion inhibitors. In addition, during the project the coating binder was changed to improve adhesion. After a systematic experimental program, a new “universal” primer with increased corrosion resistance and adhesion was formulated.

A direct to metal top coat formulation sold by Kelly-Moore …


Producing Data To Support The Detection And Understanding Of Early On-Set Corrosion In Accelerated Weathering, Stephanie Suzanne Messer Aug 2012

Producing Data To Support The Detection And Understanding Of Early On-Set Corrosion In Accelerated Weathering, Stephanie Suzanne Messer

Master's Theses

The goal of the research reported herein was to generate data towards the development of methods and protocols for detecting, quantifying, and understanding early on-set corrosion events on and above aluminum 2024-T3. The studies focused on incorporating two main fluorescent probes into a few model epoxy and/or urethane coatings to detect X and Y axis specific pH changes occurring upon and above the substrate during pre-macroscopic corrosion. The primary fluorophore used was fluorescein, a pH sensitive probe capable of detecting the changes, mainly increases in pH that accompanies aluminum corrosion. The second molecular probe, rhodamine B, was utilized to better …


The Effect Of Poss Modified Montmorillonite On Elastomer Nanocomposites, Elana Celeste Lewis Aug 2012

The Effect Of Poss Modified Montmorillonite On Elastomer Nanocomposites, Elana Celeste Lewis

Master's Theses

The goal of this thesis was to define the structural factors that determine performance in clay/rubber nanocomposites when polyhedral oligomeric silsesquioxane (POSS) is used as a dispersant. POSS has been shown previously to enhance clay, metal oxides, and carbon nanotube dispersion in thermoplastics matrices, but their performance in rubber systems has not yet been explored. There is little fundamental understanding of how POSS interacts with clay and how these modified fillers react with rubber matrices. This thesis aims to develop a greater understanding of the mechanisms of POSS-clay modification through the examination of two different POSS-clay systems and their effect …


Synthesis Of Half-Loaded Nitroimidazole Indocyanine Green Dyes Attached To Carbon Nanotubes, Courtney L. Stanford Jul 2012

Synthesis Of Half-Loaded Nitroimidazole Indocyanine Green Dyes Attached To Carbon Nanotubes, Courtney L. Stanford

Master's Theses

Indocyanine green dye is the only FDA approved NIR fluorescent dye that can be used in humans. 2-Nitroimidazoles are very effective radiosensitizers, have low cytotoxicity, and target hypoxic tissue. By coupling the two together, hypoxic tumors can be targeted and imaged. Previous work has been done to couple 2-nitroimidazole to both sides of the indocyanine green dye. This work focuses on expanding that concept to couple 2-nitroimidazole to only one side of the dye, thus allowing for the other end to be available to couple to another compound, generating a half loaded 2-nitroimidazole indocyanine green dye. In theory, this half-loaded …


Fluorescence Tagging Of Marine Low Molecular Weight Carboxylic Acids, Brian C. Gismervik Jul 2012

Fluorescence Tagging Of Marine Low Molecular Weight Carboxylic Acids, Brian C. Gismervik

Master's Theses

This thesis aims at the evaluation of the best amide bonding strategy that places a fluorescence aminomethyl coumarin tag onto a LMW organic acid in aqueous solution. A three-stage study was conducted. First, a suitable aminomethyl coumarin fluorophore was synthesized. Second, a library of acid-derivatized standards was synthesized for use in optimizing the anticipated HPLC separation of a mixture of LMW acids expected to be found in marine samples. Third, the aforementioned amide coupling strategies were screened to identify the most applicable method for our reaction conditions to the tagging of LMW organic acids in a large number of field …


Development Of A Quantitative High Throughput Method For The Early Detection Of Corrosion On Coated Aluminum, Jeffrey Clayton Foster Jun 2012

Development Of A Quantitative High Throughput Method For The Early Detection Of Corrosion On Coated Aluminum, Jeffrey Clayton Foster

Master's Theses

Eight fluorescent indicators were evaluated for their ability to detect the corrosion of aluminum metal substrates. The fluorophore Rhodamine-salicylaldehyde (RSA) was selected as a candidate for further study based on its ability to bind and detect aluminum ions at low concentrations, its selectivity for aluminum ions, its long-term stability, its solubility in our solvent-based epoxy formulation, and its compatibility with our testing method.

A recent publication suggested that an alternative method of fluorescence activation was possible—an acid-promoted ring opening that occurred in the absence of metal ions. To prove the capability of RSA to bind aluminum ions, thorough 1H …


The Development Of Transparent, Processable, Thermally-Responsive Coatings, Christopher David Roland Jun 2012

The Development Of Transparent, Processable, Thermally-Responsive Coatings, Christopher David Roland

Master's Theses

Polymer matrices are commonly used as guest-host systems for organic chromophores for use in non-linear optical materials. The chromophores must be aligned or poled in an electric field in order to impart anisotropy and non-linear activity to the material. This poling process raises several issues, the two largest being the eventual relaxation of the chromophores back into random orientations due to brownian motion, and high molecular weight polymer matrices limiting chromophore mobility during poling. The prevention of this relaxation process is an area of significant interest, especially in applications that require long term coating stability and activity. In this study, …


Synthesis Of S-Ribosyl-L-Homocysteine And Analogs Modified At The Homocysteine-C3 Position, Ruoyi Liu May 2012

Synthesis Of S-Ribosyl-L-Homocysteine And Analogs Modified At The Homocysteine-C3 Position, Ruoyi Liu

Master's Theses

Quorum sensing (QS) is a process of bacterial cell-to-cell communication that conveys population density information in order to coordinate gene expression to produce synchronized behaviors. QS regulates the expression of virulence genes in many species of bacteria; hence, the manipulation of QS pathways may lead to treatment options against many bacterial diseases. The LuxS enzyme converts S-ribosyl-L-homocysteine (SRH) into homocysteine (HCys) and 4(S),5-dihydroxypentane-2,3-dione (DPD), which is the precursor of autoinducer-2 (AI-2). Thus, inhibitors of LuxS could prevent QS by halting the conversion of SRH to AI-2 rendering the cell “uncommunicative”. This work shows the successful chemical synthesis …


Ph-Responsive Polymers For Biosurfaces: An Investigation Of Solution Properties And Surface Modifying Performance, Yuhong Wei May 2012

Ph-Responsive Polymers For Biosurfaces: An Investigation Of Solution Properties And Surface Modifying Performance, Yuhong Wei

Master's Theses

Gantrez® copolymers are used widely in the personal care industry, but their mechanisms of interaction with dental surfaces are poorly understood. In this study, we determined a number of the solution and polymer properties that control deposition, adsorption and adhesion in Gantrez® polymer aqueous solutions to model dental surfaces. QCM studies specifically showed that polymer adsorption to model hydroxyapatite surfaces occurred only in solutions with polymer concentration above c*. Adsorption and adhesion was greater in solutions of higher pH, where greater charge density along the polymer backbone was expected. For films prepared via spin-coating onto mica surfaces, addition of surfactants …


The Synthesis Of A Homologous Series Of Alkyl Lumazines And Their Application To The Dispersion Of Carbon Nanotubes, William P. Kopcha Apr 2012

The Synthesis Of A Homologous Series Of Alkyl Lumazines And Their Application To The Dispersion Of Carbon Nanotubes, William P. Kopcha

Master's Theses

In this thesis, the synthesis of a series of alkyl lumazine surfactants (LCn) is reported. Their application to the dispersion of both CoMoCAT and HiPco single-walled carbon nanotubes (SWNTs) is examined in detail and the thermal stability and chirality selection properties of dispersions made with these surfactants were compared both between themselves and with an alkyl flavin surfactant (FC12). Lumazine alkyl chain length exhibited some control over the quality and the quantity of SWNTs dispersed. LC10 was deemed most appropriate for comparison with FC12 based on considerations of solubility and nanotube individualization. …


Improved Synthesis Of The Longtailed Mealybug Pheromone, Johanna M. Bakonyi Apr 2012

Improved Synthesis Of The Longtailed Mealybug Pheromone, Johanna M. Bakonyi

Master's Theses

No abstract provided.


Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich Apr 2012

Strawberry Growth, Yield, Fruit Nutrition, And Control Of Verticillium Wilt With Pre-Plant Soil Fumigants, Ozone, And Biological Control, Justin J. Scurich

Master's Theses

Verticillium wilt is a widespread soilborne disease of strawberry historically controlled by soil fumigation with methyl bromide (MB). MB was banned by the United Nations in 1995 and will be completely phased out by 2015. Research has concentrated on alternative methods of disease control without finding a single alternative able to replace MB in widespread disease control and yield increase. For the current study, strawberries were greenhouse grown in container pots filled with soil from both infested and non-infested areas of a commercial strawberry field in Watsonville, CA. Treatments included pre-plant soil fumigation with commercially available formulations of methyl bromide, …


Responsive Materials Via Diels-Alder Chemistry, Gregory Alan Strange Mar 2012

Responsive Materials Via Diels-Alder Chemistry, Gregory Alan Strange

Master's Theses

The corrosion of infrastructure imposes a significant monetary cost, and at times human cost, upon society. Methods to improve corrosion resistance of materials are described herein which utilize the reversibility of the Diels-Alder reaction to impart thermal responsiveness upon materials. Such stimuli responsiveness can potentially play a role in self healing properties which lead to reduced cracking and thus increased corrosion protection.

Reversible Diels-Alder chemistry was utilized to manipulate the surface energy of glass substrates. Hydrophobic dieneophiles were prepared and attached to glass slides and capillaries to yield a nonwetting surface. Thermal treatment of the surfaces cleaved the Diels-Alder linkage, …


Evaluation Of The Performance Of Non-Covalent Molecular Mechanical Models For Zn2+ And Mg2+ Metal Ions, Maria Magdalena Kamm Jan 2012

Evaluation Of The Performance Of Non-Covalent Molecular Mechanical Models For Zn2+ And Mg2+ Metal Ions, Maria Magdalena Kamm

Master's Theses

Computer simulations using molecular dynamics (MD) on classical molecular mechanical

(MM) interatomic potentials can provide valuable information and quantitative

predictions about these systems. In MD calculations binding free energies of ions to

host molecules can be studied if correct ion solvation free energies in aqueous solution

are obtained. However, no MM models exist that parametrize various Zn2+ and

transition metals consistently and consider both structural and thermodynamic data

simultaneously.

The first part of our work focused on MD free energy perturbation (FEP) simulations

to derive MM interaction parameters for Zn2+ and Mg2+ ions in aqueous

solution. To obtain these parameters …