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Seismic velocity estimation from time migration

Description: This is concerned with imaging and wave propagation in nonhomogeneous media, and includes a collection of computational techniques, such as level set methods with material transport, Dijkstra-like Hamilton-Jacobi solvers for first arrival Eikonal equations and techniques for data smoothing. The theoretical components include aspects of seismic ray theory, and the results rely on careful comparison with experiment and incorporation as input into large production-style geophysical processing code… more
Date: May 31, 2007
Creator: Cameron, Maria Kourkina
Partner: UNT Libraries Government Documents Department
open access

Probing Novel Properties of Nucleons and Nuclei via Parity Violating Electron Scattering

Description: This thesis reports on two experiments conducted by the HAPPEx (Hall A Proton Parity Experiment) collaboration at the Thomas Je#11;erson National Accelerator Facil- ity. For both, the weak neutral current interaction (WNC, mediated by the Z{sup 0} boson) is used to probe novel properties of hadronic targets. The WNC interaction amplitude is extracted by measuring the parity-violating asymmetry in the elastic scattering of longitudinally polarized electrons o#11; unpolarized target hadrons. HAPP… more
Date: May 31, 2012
Creator: Mercado, Luis
Partner: UNT Libraries Government Documents Department
open access

Compensation Techniques in Accelerator Physics

Description: Accelerator physics is one of the most diverse multidisciplinary fields of physics, wherein the dynamics of particle beams is studied. It takes more than the understanding of basic electromagnetic interactions to be able to predict the beam dynamics, and to be able to develop new techniques to produce, maintain, and deliver high quality beams for different applications. In this work, some basic theory regarding particle beam dynamics in accelerators will be presented. This basic theory, along w… more
Date: May 31, 2011
Creator: Sayed, Hisham Kamal
Partner: UNT Libraries Government Documents Department
open access

Towards a Precision Measurement of Parity-Violating e-p Elastic Scattering at Low Momentum Transfer

Description: The goal of the Q-weak experiment is to make a measurement of the proton's weak charge Q{sub W}{sup p} = 1 - 4 sin{sup 2}({theta}{sub W}) to an accuracy of {approx} 4%. This would represent a {approx} 0.3% determination of the weak mixing angle sin{sup 2}({theta}{sub W}) at low energy. The measurement may be used for a precision test of the Standard Model (SM) prediction on the running of sin{sup 2}({theta}{sub W}) with energy scale. The Q-weak experiment operates at Thomas Jefferson National A… more
Date: May 31, 2012
Creator: Pan, Jie
Partner: UNT Libraries Government Documents Department
open access

Development of Modeling and Simulation for Magnetic Particle Inspection Using Finite Elements

Description: Magnetic particle inspection (MPI) is a widely used nondestructive inspection method for aerospace applications essentially limited to experiment-based approaches. The analysis of MPI characteristics that affect sensitivity and reliability contributes not only reductions in inspection design cost and time but also improvement of analysis of experimental data. Magnetic particles are easily attracted toward a high magnetic field gradient. Selection of a magnetic field source, which produces a mag… more
Date: May 31, 2003
Creator: Lee, Jun-Youl
Partner: UNT Libraries Government Documents Department
open access

Studies of Immobilized Homogeneous Metal Catalysts on Silica Supports

Description: The tethered, chiral, chelating diphosphine rhodium complex, which catalyzes the enantioselective hydrogenation of methyl-{alpha}-acetamidocinnamate (MAC), has the illustrated structure as established by {sup 31}P NMR and IR studies. Spectral and catalytic investigations also suggest that the mechanism of action of the tethered complex is the same as that of the untethered complex in solution. The rhodium complexes, [Rh(COD)H]{sub 4}, [Rh(COD){sub 2}]{sup +}BF{sub 4}{sup -}, [Rh(COD)Cl]{sub 2},… more
Date: May 31, 2003
Creator: Stanger, Keith James
Partner: UNT Libraries Government Documents Department
open access

Correlation Between Domain Behavior and Magnetic Properties of Materials

Description: Correlation between length scales in the field of magnetism has long been a topic of intensive study. The long-term desire is simple: to determine one theory that completely describes the magnetic behavior of matter from an individual atomic particle all the way up to large masses of material. One key piece to this puzzle is connecting the behavior of a material's domains on the nanometer scale with the magnetic properties of an entire large sample or device on the centimeter scale. In the firs… more
Date: May 31, 2003
Creator: Leib, Jeffrey Scott
Partner: UNT Libraries Government Documents Department
open access

Nuclear Spin Lattice Relaxation and Conductivity Studies of the Non-Arrhenius Conductivity Behavior in Lithium Fast Ion Conducting Sulfide Glasses

Description: As time progresses, the world is using up more of the planet's natural resources. Without technological advances, the day will eventually arrive when these natural resources will no longer be sufficient to supply all of the energy needs. As a result, society is seeing a push for the development of alternative fuel sources such as wind power, solar power, fuel cells, and etc. These pursuits are even occurring in the state of Iowa with increasing social pressure to incorporate larger percentages … more
Date: May 31, 2003
Creator: Meyer, Benjamin Michael
Partner: UNT Libraries Government Documents Department
open access

Process Optimization for Solid Extraction, Flavor Improvement and Fat Removal in the Production of Soymilk From Full Fat Soy Flakes

Description: Traditionally soymilk has been made with whole soybeans; however, there are other alternative raw ingredients for making soymilk, such as soy flour or full-fat soy flakes. US markets prefer soymilk with little or no beany flavor. modifying the process or using lipoxygenase-free soybeans can be used to achieve this. Unlike the dairy industry, fat reduction in soymilk has been done through formula modification instead of by conventional fat removal (skimming). This project reports the process opt… more
Date: May 31, 2003
Creator: Prawiradjaja, Stanley
Partner: UNT Libraries Government Documents Department
open access

Is Lutein a Physiologically Important Ligand for Transthyretin in Humans?

Description: Lutein and zeaxanthin are the only carotenoids accumulated in the macula of the human retina and are known as the macular pigments (MP). These pigments account for the yellow color of the macula and appear to play an important role in protecting against age-related macular degeneration (AMD). The uptake of lutein and zeaxanthin in human eyes is remarkably specific. It is likely that specific transport or binding proteins are involved. The objective is to determine whether transthyretin (TTR) is… more
Date: May 31, 2003
Creator: Chen, Liwei
Partner: UNT Libraries Government Documents Department
open access

High Growth Rate Deposition of Hydrogenated Amorphous Silicon-Germanium Films and Devices Using ECR-PECVD

Description: Hydrogenated amorphous silicon germanium films (a-SiGe:H) and devices have been extensively studied because of the tunable band gap for matching the solar spectrum and mature the fabrication techniques. a-SiGe:H thin film solar cells have great potential for commercial manufacture because of very low cost and adaptability to large-scale manufacturing. Although it has been demonstrated that a-SiGe:H thin films and devices with good quality can be produced successfully, some issues regarding grow… more
Date: May 31, 2002
Creator: Liu, Yong
Partner: UNT Libraries Government Documents Department
open access

Laser Processing of Metals and Polymers

Description: A laser offers a unique set of opportunities for precise delivery of high quality coherent energy. This energy can be tailored to alter the properties of material allowing a very flexible adjustment of the interaction that can lead to melting, vaporization, or just surface modification. Nowadays laser systems can be found in nearly all branches of research and industry for numerous applications. Sufficient evidence exists in the literature to suggest that further advancements in the field of la… more
Date: May 31, 2012
Creator: Singaravelu, Senthilraja
Partner: UNT Libraries Government Documents Department
open access

Meausrement of the Neutron Radius of {sup 208}Pb Through Parity Violation in Electron Scattering

Description: In contrast to the nuclear charge densities, which have been accurately measured with electron scattering, the knowledge of neutron densities still lack precision. Previous model-dependent hadron experiments suggest the difference between the neutron radius, R{sub n}, of a heavy nucleus and the proton radius, R{sub p}, to be in the order of several percent. To accurately obtain the difference, R{sub n}-R{sub p}, which is essentially a neutron skin, the Jefferson Lab Lead ({sup 208}Pb) Radius Ex… more
Date: May 31, 2013
Creator: Saenboonruang, Kiadtisak
Partner: UNT Libraries Government Documents Department
open access

Optimal Real-time Dispatch for Integrated Energy Systems

Description: This report describes the development and application of a dispatch optimization algorithm for integrated energy systems (IES) comprised of on-site cogeneration of heat and electricity, energy storage devices, and demand response opportunities. This work is intended to aid commercial and industrial sites in making use of modern computing power and optimization algorithms to make informed, near-optimal decisions under significant uncertainty and complex objective functions. The optimization algo… more
Date: May 31, 2007
Creator: Firestone, Ryan Michael
Partner: UNT Libraries Government Documents Department
open access

Functionalized Materials From Elastomers to High Performance Thermoplastics

Description: Synthesis and incorporation of functionalized materials continues to generate significant research interest in academia and in industry. If chosen correctly, a functional group when incorporated into a polymer can deliver enhanced properties, such as adhesion, water solubility, thermal stability, etc. The utility of these new materials has been demonstrated in drug-delivery systems, coatings, membranes and compatibilizers. Two approaches exist to functionalize a material. The desired moiety can… more
Date: May 31, 2003
Creator: Salazar, Laura Ann
Partner: UNT Libraries Government Documents Department
open access

Microstructural evolution of eutectic Au-Sn solder joints

Description: Current trends toward miniaturization and the use of lead(Pb)-free solder in electronic packaging present new problems in the reliability of solder joints. This study was performed in order to understand the microstructure and microstructural evolution of small volumes of nominally eutectic Au-Sn solder joints (80Au-20Sn by weight), which gives insight into properties and reliability.
Date: May 31, 2002
Creator: Song, Ho Geon
Partner: UNT Libraries Government Documents Department
open access

Synthesis of Polycyclic Natural Products

Description: With the continuous advancements in molecular biology and modern medicine, organic synthesis has become vital to the support and extension of those discoveries. The isolations of new natural products allow for the understanding of their biological activities and therapeutic value. Organic synthesis is employed to aid in the determination of the relationship between structure and function of these natural products. The development of synthetic methodologies in the course of total syntheses is im… more
Date: May 31, 2003
Creator: Nguyen, Tuan Hoang
Partner: UNT Libraries Government Documents Department
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