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Search for the Higgs Boson and Technicolor Particles in p anti-p Colisions at sqrt(s) = 1.8 TeV

Description: In the Standard Model (SM) of the elementary particles, the interactions among the known fundamental fermions (leptons and quarks) are mediated through gauge bosons which obey the symmetry: SU(3) {circle_times} SU(2) {circle_times} U(1). More precisely, the electroweak interaction [4-6] is described by a gauge symmetry SU(2) {circle_times} U(1) which is broken spontaneously. The electroweak symmetry breaking is implemented by the introduction of a complex scalar Higgs field which has a non-zero… more
Date: November 1, 1999
Creator: Cortabitarte, Rocio Vilar & /Cantabria U., Santander
Partner: UNT Libraries Government Documents Department
open access

Low temperature y-ray spectrometers based on bulk superconducting and dielectric absorber crystals

Description: Many areas of research rely on the detection of radiation, in the form of single photons or particles. By measuring the photons or particles coming from an object a lot can be learned about the object under study. In some cases there is a simple need to know the number of photons coming from the source. In cases like this a simple counter, like a Geiger-Mueller survey meter, will suffice. In other cases one want to know the spectral distribution of the photons coming from the source. In cases l… more
Date: November 19, 1999
Creator: Netel, H
Partner: UNT Libraries Government Documents Department
open access

Elemental speciation in biomolecules by LC-ICP-MS with magnetic sector and collision cell instruments

Description: A methodology that can monitor and identify inorganic elements in biological and environmental systems was developed. Size exclusion chromatography (SEC) separates biomolecules, which are then nebulized by a microconcentric nebulizer. The resulting aerosol is desolved and introduced into either a high resolution ICP-MS device or a quadrupole device with a collision cell. Because of the high sensitivity and spectral resolution and high sample introduction efficiency, many unusual or difficult el… more
Date: November 8, 1999
Creator: Wang, Jin
Partner: UNT Libraries Government Documents Department
open access

Anisotropic magnetization and transport properties of RAgSb{sub 2} (R=Y, La-Nd, Sm, Gd-Tm)

Description: This study of the RAgSb{sub 2} series of compounds arose as part of an investigation of rare earth intermetallic compounds containing antimony with the rare earth in a position with tetragonal point symmetry. Materials with the rare earth in a position with tetragonal point symmetry frequently manifest strong anisotropies and rich complexity in the magnetic properties, and yet are simple enough to analyze. Antimony containing intermetallic compounds commonly possess low carrier densities and ha… more
Date: November 8, 1999
Creator: Myers, Kenneth D.
Partner: UNT Libraries Government Documents Department
open access

Kinetics and mechanism of the oxidation of alkenes and silanes by hydrogen peroxide catalyzed by methylrhenium trioxide (MTO) and a novel application of electrospray mass spectrometry to study the hydrolysis of MTO

Description: Conjugated dienes were oxidized by hydrogen peroxide with methylrhenium trioxide (MTO) as catalyst. Methylrhenium bis-peroxide was the major reactive catalyst present. Hydroxyalkenes and trisubstituted silane were also tested. Mechanisms for each of these reactions are presented.
Date: November 8, 1999
Creator: Tan, Haisong
Partner: UNT Libraries Government Documents Department
open access

Processing of Mo-Si-B intermetallics by extrusion and oxidation properties of the extruded Tl-MoSi{sub 2}-MoB System

Description: An extrusion process was developed that is able to consistently produce large quantities of Mo-Si-B rods without the presence of defects. Binder removal from the extruded rods was studied in detail and it was determined that heating rates on the order of 0.02{degree}/minute (1.2{degree}/hour) are necessary to remove the binder without the formation of defects. This low heating rate resulted in debinding times in excess of 70 hours (approximately 3 days). Wicking was investigated as a means to d… more
Date: November 8, 1999
Creator: Summers, Eric
Partner: UNT Libraries Government Documents Department
open access

High temperature phase equilibria studies in the Bi-Sr-Ca-Cu-O-Ag system

Description: A variety of experimental techniques were utilized to examine the high temperature phase equilibria in the Bi-Sr-Ca-Cu-O-Ag system. Quenching studies were used to determine the liquid solubility of Ag in the Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} (Bi2212) melt and the details of the peritectic decomposition pathway of Bi2212 as a function on Ag content and oxygen partial pressure (PO{sub 2}). A liquid immiscibility region between oxide and Ag liquids in the 8--98 at% range was found above 900 C.… more
Date: November 8, 1999
Creator: Margulies, Lawrence
Partner: UNT Libraries Government Documents Department
open access

A new sieving matrix for DNA sequencing, genotyping and mutation detection and high-throughput genotyping with a 96-capillary array system

Description: Capillary electrophoresis has been widely accepted as a fast separation technique in DNA analysis. In this dissertation, a new sieving matrix is described for DNA analysis, especially DNA sequencing, genetic typing and mutation detection. A high-throughput 96 capillary array electrophoresis system was also demonstrated for simultaneous multiple genotyping. The authors first evaluated the influence of different capillary coatings on the performance of DNA sequencing. A bare capillary was compare… more
Date: November 8, 1999
Creator: Gao, David
Partner: UNT Libraries Government Documents Department
open access

Preliminary studies on identification of inorganic species in complex mixtures by electrospray mass spectrometry in the counter ion mode

Description: Suppression of mass spectral peaks due to matrix problem is a major hurdle to overcome during identification work. So far, preliminary studies have been done in investigating solutions containing various percentages of nitric and hydrochloric acid. Since other anions would also be present in real samples, also needed to be examined is how the extent of suppression of metal complexes by Cl{sup {minus}} compares with suppression by other anions such as PO{sub 4}{sup 3{minus}} or SO{sub 4}{sup 2{m… more
Date: November 8, 1999
Creator: Mollah, Sahana
Partner: UNT Libraries Government Documents Department
open access

Surface plasmon enhanced interfacial electron transfer and resonance Raman, surface-enhanced resonance Raman studies of cytochrome C mutants

Description: Surface plasmon resonance was utilized to enhance the electron transfer at silver/solution interfaces. Photoelectrochemical reductions of nitrite, nitrate, and CO{sub 2} were studied on electrochemically roughened silver electrode surfaces. The dependence of the photocurrent on photon energy, applied potential and concentration of nitrite demonstrates that the photoelectrochemical reduction proceeds via photoemission process followed by the capture of hydrated electrons. The excitation of plasm… more
Date: November 8, 1999
Creator: Zheng, Junwei
Partner: UNT Libraries Government Documents Department
open access

Transport processes in directional solidification and their effects on microstructure development

Description: The processing of materials with unique electronic, mechanical, optical and thermal properties plays a crucial role in modern technology. The quality of these materials depend strongly on the microstructure and the solute/dopant fields in the solid product, that are strongly influenced by the intricate coupling of heat and mass transfer and melt flow in the growth systems. An integrated research program is developed that include precisely characterized experiments and detailed physical and nume… more
Date: November 8, 1999
Creator: Mazumder, Prantik
Partner: UNT Libraries Government Documents Department
open access

Studies of beam dynamics in relativistic klystron two-beam accelerators

Description: Two-beam accelerators (TBAs) based upon free-electron lasers (FELs) or relativistic klystrons (RK-TBAs) have been proposed as efficient power sources for next generation high-energy linear colliders. Studies have demonstrated the possibility of building TBAs from X-band ({approximately}8-12 GHz) through Ka band ({approximately} 30-35 GHz) frequency regions. Provided that further prototyping shows stable beam propagation with minimal current loss and production of good quality, high-power rf fie… more
Date: November 1, 1999
Creator: Lidia, Steven M.
Partner: UNT Libraries Government Documents Department
open access

Application of spectral hole burning to the study of in vitro cellular systems

Description: Chapter 1 of this thesis describes the various stages of tumor development and a multitude of diagnostic techniques used to detect cancer. Chapter 2 gives an overview of the aspects of hole burning spectroscopy important for its application to the study of cellular systems. Chapter 3 gives general descriptions of cellular organelles, structures, and physical properties that can serve as possible markers for the differentiation of normal and cancerous cells. Also described in Chapter 3 are the p… more
Date: November 8, 1999
Creator: Milanovich, Nebojsa
Partner: UNT Libraries Government Documents Department
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