Physical Sciences and Mathematics Commons^™

Simultaneous Determination Of Multiple Actinide Elements In A Variety Of Soils Utilizing A Standardized Sequential Extraction Protocol, Sherry Alina Faye

UNLV Theses, Dissertations, Professional Papers, and Capstones

To obtain a better understanding of the mobility of actinide element contaminants in the environment, the association of the contaminants with specific host phases of soils and sediments must be investigated. This investigation is most commonly conducted using sequential extraction techniques that employ the selective dissolution of soil phases with increasingly aggressive chemical treatment. Though several sequential extraction studies exist in literature, conclusions cannot be made by direct comparison of data due to the lack of uniformity in the protocols used. This work aims to continue development of a standard sequential extraction protocol and expanding its capabilities to include the …

Distribution Of Dissolved Trace Metals And Carbon System Parameters In The Surface Waters Of The Hillsborough River And Tampa Bay, Matthew Matthias Elliott

USF Tampa Graduate Theses and Dissertations

This work represents a first look at the general spatial distribution of trace metals and the inorganic carbon system in the surface waters of Tampa Bay. Tampa Bay's chemical environment bears many influences ranging from hydrological and geological to anthropogenic and meteorological. A large y-shaped estuary on the west-central side of the Florida Peninsula, Tampa Bay extends over 400 square miles and has a 2200 square mile watershed that includes extensive swamps, scrub, agricultural lands and densely urbanized areas. Reaching 37 miles from the northernmost point of Old Tampa Bay to the mouth of the estuary near the Sunshine Skyway …

Development And Application Of Explicitly Correlated Wave Function Based Methods For The Investigation Of Optical Properties Of Semiconductor Nanomaterials, Jennifer Mary Elward

Dissertations - ALL

Semiconductor nanoparticles, or quantum dots (QDs), are well known to have very unique optical and electronic properties. These properties can be controlled and tailored as a function of several influential factors, including but not limited to the particle size and shape, effect of composition and heterojunction as well as the effect of ligand on the particle surface. This customizable nature leads to extensive experimental and theoretical research on the capabilities of these quantum dots for many application purposes.

However, in order to be able to understand and thus further the development of these materials, one must first understand the fundamental …

Nanocarbon Immobilized Membrane For Separation And Analysis, Madhuleena Bhadra

Dissertations

Membrane processes classically cover a wide range of applications associated with various aspects of separation and purification. Over the last few years, membrane based processes have received much interest due to their compact and modular architecture, low energy consumption and cost effective separation. With the development of diverse nanomaterials which can serve as nanosorbents, or provide specific morphology for selective solute transport, recent years have witnessed the emergence of nanocarbon based membranes that can address some of the limitations of conventional membrane processes and make feasible the next generation of breakthroughs.

The objective of this research is the exploration of …

Syntheses Of Precursors To Fluorine-18 Labeled Pet Imaging Agents, Lindsay B. Boling

Chancellor’s Honors Program Projects

No abstract provided.

Characterization And Optimization Of Extraction Chromatography Resins For Rapid Separations For Safeguard And Nuclear Forensics Purposes, Audrey Roman

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this work, extraction chromatography resins, DGA and UTEVA, were characterized under various conditions in order to identify novel rapid separations for safeguards and nuclear forensic purposes. For safeguards purposes, mixed matrices containing some of the largest components found in used fuel and either Am, Pu, or U were characterized on DGA and UTEVA resins in order to determine any effects from the addition of these constituents. Results indicated that 5 M HNO₃ would be an optimal loading condition due to the consistent actinide adsorption in the presence of the additional used fuel components. Investigations of varying the anion …

Enzyme-Based Nitric Oxide Releasing Thin Films And Scaffolds, Mutha Merenna Nuwan Bhagya Gunasekera

ETD Archive

Nitric oxide synthase enzyme (NOS) embedded in thin films and scaffolds, when exposed to a solution of its substrate arginine, a source of reducing equivalents, and other required ingredients of the NOS reaction, can release fluxes of nitric oxide (NO). The latter is a molecule known to counteract platelet aggregation, and thus can prevent the thrombosis cascade on the surfaces of implantable medical devices. Therefore NO antithrombogenic regimens such as active coatings and embedded scaffolds have the potential to increase the lifespan of implantable biomaterials. Layer-by-layer electrostatic adsorption allows for assembly of multi-component protein/polyelectrolytes nanostructured films. Electrospun fiber matrices may …

The Effect Of Manipulatives On Students' Understanding Of Chemistry Concepts, Jasmine W. Banks

LSU Master's Theses

The purpose of this study was to assess the effectiveness of manipulatives on chemistry concepts. Manipulative activities were designed for four chemistry topics: Dimensional Analysis, Ionic Formulas, Molecular Shapes, and Stoichiometry. Seventy-five high school students were divided into a control or experimental group. The control group solved problems in small groups, while the experimental group used manipulatives to complete a guided activity. Students in the control group scored significantly higher on the posttest for the Dimensional Analysis and Ionic Formulas activities. There was no significant difference in the posttest scores for the Molecular Shapes and Stoichiometry posttest. While manipulatives can …

Advancements In The Design, Synthesis, And Application Of Polybenzimidazoles, Alexander Lanier Gulledge

Theses and Dissertations

The overall goal of the work presented within this thesis is to investigate, understand, and develop structure-property relationships in regards to polymer structure, membrane stability, and device performance. Previous work has shown that material properties such as acid loading, proton conductivity, mechanical integrity, and device performance can be attributed to polymer structure, chemical functionality, and polymer architecture (homo, random, co-polymer etc.). Developing and understanding these relationships is critical to the advancement of fuel cell technology. Within this thesis, several of these relationships are investigated and reported.

Novel polymers and copolymer systems have been developed in this research and have significantly …