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Investigation Of The Structure And Dynamics Of Regioisomeric Eu³⁺ And Gd³⁺ Chelates Of Nb-Dotma: Implications For Mri Contrast Agent Design, Benjamin Charles Webber 2013 Portland State University

Investigation Of The Structure And Dynamics Of Regioisomeric Eu³⁺ And Gd³⁺ Chelates Of Nb-Dotma: Implications For Mri Contrast Agent Design, Benjamin Charles Webber

Dissertations and Theses

The detection of disease and abnormal pathology by magnetic resonance imaging (MRI) has been aided significantly by the use of gadolinium (Gd3+)-based contrast agents (CAs) over the past three decades. MRI and MRI CAs play a critical role in diagnosing tumors and diseases of the central nervous system. The agents used clinically have been shown to safely increase MRI contrast despite the toxicity of Gd3+, owing to the high kinetic and thermodynamic stability of these chelates. However, current CAs enhance contrast at a small fraction of what is theoretically possible. This leads to the necessity of introducing ...


Comparative Metabolism Of Phenanthro[3,4-B]Thiophene And Benzo[C]Phenanthrene, Jaquan M. Williams 2013 Selected Works

Comparative Metabolism Of Phenanthro[3,4-B]Thiophene And Benzo[C]Phenanthrene, Jaquan M. Williams

Jaquan M Williams

ABSTRACT OF THESIS Comparative Metabolism of Phenanthro[3,4-b]Thiophene And Benzo[c]Phenanthrene Polycyclic aromatic hydrocarbons (PAHs) and their sulfur-heterocyclic analogs (thia-PAHs) are commonly occurring persistent environmental contaminants formed by incomplete combustion of organic matter. A number of thia-PAHs have shown significant mutagenic and carcinogenic activities. As noted with PAHs, these chemical contaminants also require metabolic activation in order to exhibit their mutagenic and carcinogenic effects. In the present study, a comparison of the metabolism of highly mutagenic phenanthro[3,4-b]thiophene (P[3,4-b]T) and its weakly mutagenic carbon analogue, benzo[c]phenanthrene (B[c]P), was ...


Investigation Of Storage-Phosphor Autoradiography For The Rapid Quantitative Screening Of Air Filters For Emergency Response Purposes, Athena Marie Gallardo 2013 University of Nevada, Las Vegas

Investigation Of Storage-Phosphor Autoradiography For The Rapid Quantitative Screening Of Air Filters For Emergency Response Purposes, Athena Marie Gallardo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Past nuclear accidents, such as Chernobyl, resulted in a large release of radionuclides into the atmosphere. Radiological assessment of the vicinity of the site of the incident is vital to assess the exposure levels and dose received by the population and workers. Therefore, it is critical to thoroughly understand the situation and risks associated with a particular event in a timely manner in order to properly manage the event. Current atmospheric radiological assessments of alpha emitting radioisotopes include acquiring large quantities of air samples, chemical separation of radionuclides, sample mounting, counting through alpha spectrometry, and analysis of the data. The ...


Neutron Scintillation Detectors Based On Polymers Containing Lithium-6 For Radiation Portal Monitor Applications, Andrew Neil Mabe 2013 University of Tennessee, Knoxville

Neutron Scintillation Detectors Based On Polymers Containing Lithium-6 For Radiation Portal Monitor Applications, Andrew Neil Mabe

Doctoral Dissertations

The work presented herein describes an investigation of four main types of thin film polymer scintillators containing 6Li [lithium-6] for neutron detection: polystyrene containing 6LiF [lithium-6 fluoride] and a preblended fluor mixture comprising 2,5-diphenyloxazole and 1,4-bis(5-phenyloxazol-2-yl)benzene; poly(styrene-co-lithium maleate) containing salicylic acid; poly[styrene-co-lithium maleate-co-2-phenyl-5-(4-vinylphenyl)oxazole]; and poly(styrene-co-lithium 4-vinylbenzoate). A variety of chemical and physical characterizations as well as optical and scintillation characterizations were performed to guide the development of optimized compositions of each type of polymer film. The scintillation performances of optimized compositions ...


A. Catalysis Of Co-Prox By Water-Soluble Rhodium Fluorinated Porphyrins B. Studies Toward Fluorination Of Electron Rich Aromatics By Nucleophilic Fluoride, Shri Harsha Uppaluri 2013 University of Nebraska-Lincoln

A. Catalysis Of Co-Prox By Water-Soluble Rhodium Fluorinated Porphyrins B. Studies Toward Fluorination Of Electron Rich Aromatics By Nucleophilic Fluoride, Shri Harsha Uppaluri

Student Research Projects, Dissertations, and Theses - Chemistry Department

The rhodium(III) derivative of a water soluble, heavily fluorinated porphyrin is shown to catalyze the low temperature, low pressure selective oxidation of carbon monoxide in hydrogen gas streams for use in fuel cell applications. The catalytic activity is a direct result of the removal of electron density from the metal center. Selectivity for CO oxidation is a direct consequence of fluorination of the porphyrin periphery, since these substituents enhance the rate of the reaction and prevent the formation of Rh(II)-Rh(II) dimmers. Significantly, the dramatic increase in rhodium hydride acidity caused by fluorination precludes hydrogen activation and ...


Microspheres For Liver Radiomicrospheres Therapy And Planning, Alejandro Amor-Coarasa 2013 Florida International University

Microspheres For Liver Radiomicrospheres Therapy And Planning, Alejandro Amor-Coarasa

FIU Electronic Theses and Dissertations

Liver cancer accounts for nearly 10% of all cancers in the US. Intrahepatic Arterial Radiomicrosphere Therapy (RMT), also known as Selective Internal Radiation Treatment (SIRT), is one of the evolving treatment modalities. Successful patient clinical outcomes require suitable treatment planning followed by delivery of the microspheres for therapy. The production and in vitro evaluation of various polymers (PGCD, CHS and CHSg) microspheres for a RMT and RMT planning are described. Microparticles with a 30±10 µm size distribution were prepared by emulsion method. The in vitro half-life of the particles was determined in PBS buffer and porcine plasma and their ...


Forensic Signatures Of Chemical Process History In Uranium Oxides, Jonathan Plaue 2013 University of Nevada, Las Vegas

Forensic Signatures Of Chemical Process History In Uranium Oxides, Jonathan Plaue

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation comprehensively explores and develops new tools for nuclear forensic science to facilitate the identification of chemical process history in uranium oxides. Nuclear forensics is an emerging discipline motivated by the need to prevent and combat malevolent acts involving nuclear and radiological materials. This dissertation examined process signatures in uranium oxide powders, precursors, and sintered fuel pellets.

Signatures were investigated on set of powder and pellet exemplars synthesized in the laboratory and a set of real‐world samples with process information obtained from the literature or manufacturer. The examined techniques included morphology as revealed by scanning electron microscopy, near ...


Separation Of Tc From U And Development Of Metallic Tc Waste Forms, Edward Mausolf 2013 University of Nevada, Las Vegas

Separation Of Tc From U And Development Of Metallic Tc Waste Forms, Edward Mausolf

UNLV Theses, Dissertations, Professional Papers, and Capstones

The isotope Technetium-99 (99Tc) is a major fission product of the nuclear industry. In the last decade, approximately 20 tons of 99Tc have been produced by the US nuclear industry. Due to its long half-life (t1/2 = 214,000 yr), beta radiotoxicity, and high mobility as pertechnetate [TcO4]-, Tc represents long-term concern to the biosphere. Various options have been considered to manage 99Tc. One of them is its separation from spent fuel, conversion to the metal and incorporation into a metallic waste form for long-term disposal. After dissolution of spent fuel in nitric acid and extraction ...


Density Functional Theory And The Calculation Of Tcmg2O4 Spinel Lattice Parameters, Jon Karlo Macias 2013 California Polytechnic State University - San Luis Obispo

Density Functional Theory And The Calculation Of Tcmg2O4 Spinel Lattice Parameters, Jon Karlo Macias

Physics

The cohesive energy, lattice constant and bulk modulus of two simple HCP crystal structures of magnesium and technetium were calculated using the vienna ab initio simulation package (VASP) which is based on density functional theory (DFT). The same properties were determined for TcMg2O4 spinel. The theoretical results of the lattice constant of the pure crystals were compared to experimental results and found to be in excellent agreement with a difference of less than 2%. The results for the lattice constant of the TcMg2O4 spinel were found to be in excellent agreement as well with ...


Synthesis: What We Have Learned From The East Texas Radiocarbon Database, Robert Z. Selden Jr., Timothy K. Perttula 2013 Archeological & Environmental Consultants, LLC

Synthesis: What We Have Learned From The East Texas Radiocarbon Database, Robert Z. Selden Jr., Timothy K. Perttula

CRHR: Archaeology

This poster provides a short overview of what we have learned from the East Texas Radiocarbon Database since it became available on the Council of Texas Archeologists’ website in 2011. These successes are numerous and include the advancement of novel methodological approaches; an improvement in our comprehension of the temporal nuances within the East Texas Archaic; the division of the East Texas Woodland period into Early, Middle and Late; the refinement of Caddo temporal chronology – particularly from a geographic perspective -- and it has provided one line of evidence to use to argue for the fluorescence of corn-based agriculture during the ...


A Preliminary Temporal Analysis Of The East Texas Archaic, Robert Z. Selden Jr. 2013 Center for Regional Heritage Research, Stephen F. Austin State University

A Preliminary Temporal Analysis Of The East Texas Archaic, Robert Z. Selden Jr.

CRHR: Archaeology

This article presents preliminary findings of a temporal analysis of the East Texas Archaic based upon the examination of radiocarbon dates that have deposits that date to the period. All assays employed in this effort were collected from research and cultural resource management reports and publications, synthesized, then recalibrated in version 4.1.7 of OxCal.


New Radiocarbon Dates From East Texas Caddo Sites, Timothy K. Perttula, Robert Z. Selden Jr. 2013 Archeological & Environmental Consultants, LLC

New Radiocarbon Dates From East Texas Caddo Sites, Timothy K. Perttula, Robert Z. Selden Jr.

CRHR: Archaeology

In this article, we report on new radiocarbon dates obtained from five Caddo sites in East Texas. The radiocarbon samples are charred organic remains scraped off of one surface of whole vessels or sherds. These samples are from the Johns (41CP12), Shelby Mound (41CP71), Gilbert (41RA13), Henry Spencer (41UR315), and Henry Williams (41UR318) sites. All of the dates are calibrated using OxCal v4.1.7 (Bronk Ramsey 2012), with atmospheric data from Reimer et al. (2009).


Additional New Radiocarbon Dates From East Texas Caddo Sites, Timothy K. Perttula, Robert Z. Selden Jr. 2013 Archeological & Environmental Consultants, LLC

Additional New Radiocarbon Dates From East Texas Caddo Sites, Timothy K. Perttula, Robert Z. Selden Jr.

CRHR: Archaeology

As a follow-up to the radiocarbon analyses reported by Perttula and Selden (2013), in this article, we report on five new radiocarbon dates obtained from Caddo sites in East Texas. The radiocarbon samples are charred organic remains scraped off of one surface of whole vessels or sherds. These samples are from the Ware Acres site (41GG31), the H. C. Slider site in Cherokee County, an unknown site in the upper Neches River basin in Smith County (9-SC), and an unknown Titus phase site (11-BCJ) in the Big Cypress Creek basin. All of the dates are calibrated using OxCal v4.1 ...


Computer Code Verification And Cross Section Calculation For Promethium-147, Rita Inez Zell-Lusk 2013 University of Tennessee, Knoxville

Computer Code Verification And Cross Section Calculation For Promethium-147, Rita Inez Zell-Lusk

Nuclear Engineering Reports

The goals of this research are to (1) verify the predictions and accuracy of two computer codes which will be utilized in future research on Pm-147 production with data from a previous experiment and to (2) measure the cross section of Pm-147 for single neutron capture producing Pm-148 ground state and Pm-148 metastable state. The research in goal (1) used previous data obtained by James H. Hinderer in 2010 and a sample of Promethium-147 prepared by Rose Boll in 2006. The main elements of the new research done here included a correction of Mr. Hinderer’s data and the subsequent ...


Temporal Dynamics Of East Texas Caddo Sites With 10 Or More Radiocarbon Dates, Robert Z. Selden Jr., Timothy K. Perttula 2013 Center for Regional Heritage Research, Stephen F. Austin State University

Temporal Dynamics Of East Texas Caddo Sites With 10 Or More Radiocarbon Dates, Robert Z. Selden Jr., Timothy K. Perttula

CRHR: Archaeology

This article represents supplementary data (see Selden and Perttula 2013) highlighting the specifics of date combination and the subsequent production of summed probability distribution samples for Caddo sites in East Texas. All radiocarbon (14C ) dates employed in this effort were collected from research and cultural resource management (CRM) reports and publications, synthesized, then recalibrated in version 4.1.7 of OxCal (Bronk Ramsey 2012) using IntCal09 (Reimer et al. 2009) (Perttula and Selden 2011).


Recycling And Reuse Of Radioactive Materials, Thomas Joseph O'dou 2012 University of Nevada, Las Vegas

Recycling And Reuse Of Radioactive Materials, Thomas Joseph O'Dou

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Radiochemistry Program at the University of Nevada, Las Vegas (UNLV) has a Radiation Protection Program that was designed to provide students with the ability to safely work with radioactive materials in quantities that are not available in other academic environments. Requirements for continuous training and supervision make this unique program capable of turning out graduates that have an understanding of contamination and dose control techniques that complement their knowledge of the elements that they work with. The Program has also adopted a radionuclide recovery and reuse program that has provided materials from other universities, government agencies, and private companies ...


Elemental Contributions From Minor And Major Constituents Of Bone On The Separation Of Radiostrontium, Ashlee Rae Dailey 2012 University of Nevada, Las Vegas

Elemental Contributions From Minor And Major Constituents Of Bone On The Separation Of Radiostrontium, Ashlee Rae Dailey

UNLV Theses, Dissertations, Professional Papers, and Capstones

While many methods exist to separate and analyze radionuclides from a variety of environmental matrices, the performance of all of these methods is often limited by other interfering constituents that are consistently found in most of these samples. The presence of such constituents can significantly reduce the recovery of the radioisotopes of interests and lead to incomplete separations.

Strontium has the same oxidation state and a similar atomic radius as calcium and is therefore readily able to substitute for calcium in lattice sites. This similarity in behavior leads to the preferential accumulation of strontium in newly formed bone. The study ...


Molecular Forensic Science Analysis Of Nuclear Materials, Dallas Reilly 2012 University of Nevada, Las Vegas

Molecular Forensic Science Analysis Of Nuclear Materials, Dallas Reilly

UNLV Theses, Dissertations, Professional Papers, and Capstones

Concerns over the proliferation and instances of nuclear material in the environment have increased interest in the expansion of nuclear forensics analysis and attribution programs. A new related field, molecular forensic science (MFS) has helped meet this expansion by applying common scientific analyses to nuclear forensics scenarios. In this work, MFS was applied to three scenarios related to nuclear forensics analysis. In the first, uranium dioxide was synthesized and aged at four sets of static environmental conditions and studied for changes in chemical speciation. The second highlighted the importance of bulk versus particle characterizations by analyzing a heterogeneous industrially prepared ...


Mußestudien Und Radiochemie: Eine Fruchtpfolle Synthese, Winfried S. Peters 2012 Selected Works

Mußestudien Und Radiochemie: Eine Fruchtpfolle Synthese, Winfried S. Peters

Winfried S. Peters

This makes no sense at all!


Evaluating Actinide Sorption To Graphite With Regards To Triso Repository Performance, Corey Christopher Keith 2012 University of Nevada, Las Vegas

Evaluating Actinide Sorption To Graphite With Regards To Triso Repository Performance, Corey Christopher Keith

UNLV Theses, Dissertations, Professional Papers, and Capstones

Graphite has the potential for inclusion in nuclear waste for disposal in waste repository settings. Implementation of High Temperature Gas-cooled Reactors contributes to this potential through use of TRISO fuel, if direct disposal of the graphite matrix surrounding the fuel is employed. The inclusion of the large mass and volume in the TRISO fuel waste form differs significantly from used light water reactor fuel waste forms, requiring new performance models to describe the behavior in a repository setting. The purpose of this study is to evaluate the potential for the graphite to improve actinide, specifically uranium and neptunium, retardation from ...


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