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Development of Trivalent Ytterbium Doped Fluorapatites for Diode-Pumped Laser Applications

Description: One of the major motivators of this work is the Mercury Project, which is a 1 kW scalable diode-pumped solid-state laser system under development at Lawrence Livermore National Laboratory (LLNL). Major goals include 100 J pulses, 10% wallplug efficiency, 10 Hz repetition rate, and a 5 times diffraction limited beam. To achieve these goals the Mercury laser incorporates ytterbium doped Sr{sub 5}(PO{sub 4}){sub 3}F (S-FAP) as the amplifier gain medium. The primary focus of this thesis is a full u… more
Date: June 21, 2000
Creator: Bayramian, A. J.
Partner: UNT Libraries Government Documents Department
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Bond and Low Cycle Fatigue Behavior of Thermoset Composite Reinforcing for the Concrete Industry

Description: This thesis encompasses two separate research projects. The first project, described in Chapter 2 was a project investigating the fatigue behavior of thermoset Fiber Composite (FC) sandwich wall ties. The second research project detailed in this thesis was a project studying the bond and tensile properties of FC rod and FC fibers.
Date: September 21, 1990
Creator: Barnes, Bruce
Partner: UNT Libraries Government Documents Department
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Nonphotochemical Hole Burning and Dispersive Kinetics in Amorphous Solids

Description: Results covering burn intensities in the nW to {mu}W/cm{sup 2} range, of dispersive hole growth kinetics are reported for Oxazine 720 in glycerol glasses and polyvinyl alcohol polymer films and their deuterated analogues. A theoretical model which employs a distribution function for the hole burning rate constant based upon a Gaussian distribution for the tunnel parameter is shown to accurately describe the kinetic data. This model incorporates the linear electron-phonon coupling. A method for … more
Date: September 21, 1990
Creator: Kenney, M. J.
Partner: UNT Libraries Government Documents Department
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The interactions of water and perfluorodiethyl ether on Ru(100)

Description: We have studied the interactions of water and perfluorodiethyl ether on Ru(100) in order to model the effects of surface structure and humidity on the bonding and decomposition of perfluoroalkyl ether lubricants with metal surfaces. In order to understand the interactions on Ru(100), we have first investigated the interactions of each of these adsorbates alone on the clean surface. The interactions of water with Ru(100) have been studied using both thermal desorption spectroscopy (TDS) and elec… more
Date: September 21, 1990
Creator: Leavitt, Pam
Partner: UNT Libraries Government Documents Department
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Neutral technicolor pseudo Goldstone bosons production and QCD (quantum chromodynamics) background at the SSC (Superconducting Super Collider)

Description: The production of the neutral technicolor pseudo Goldstone bosons, P{sup 0}{prime}and P{sub 8}{sup 0}{prime}, at large transverse momentum in pp collisions, pp {yields} g(q)P{sup 0}{prime} (P{sub 8}{sup 0}{prime})X has been investigated in reactions at a high energy collider such as the SSC. The major two-body and three-body decay modes in tree diagrams are investigated in detail. The t{bar t} decay channel would dominate both the decays of P{sup 0}{prime} and P{sub 8}{sup 0}{prime} if it is al… more
Date: September 21, 1990
Creator: Kuo, Wang-Chuang
Partner: UNT Libraries Government Documents Department
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Benchmarks and models for 1-D radiation transport in stochastic participating media

Description: Benchmark calculations for radiation transport coupled to a material temperature equation in a 1-D slab and 1-D spherical geometry binary random media are presented. The mixing statistics are taken to be homogeneous Markov statistics in the 1-D slab but only approximately Markov statistics in the 1-D sphere. The material chunk sizes are described by Poisson distribution functions. The material opacities are first taken to be constant and then allowed to vary as a strong function of material tem… more
Date: August 21, 2000
Creator: Miller, D. S.
Partner: UNT Libraries Government Documents Department
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First observation of the Charmless Decay B to K pi0pi0 and Study of its Dalitz Plot Structure

Description: Results for the first measurement of the inclusive branching and CP asymmetry of the charmless 3-body decay B{sup +} {yields} K{sup +}{pi}{sup 0}{pi}{sup 0} are presented. The analysis uses a data sample with an integrated luminosity of 429.0 fb{sup -1}, recorded by the BABAR detector at the PEP-II asymmetric B Factory. This sample corresponds to 470.9 {+-} 2.8 million B{bar B} pairs. Measurements of the branching fractions (B) and CP asymmetries (A{sub CP}) of some of the intermediate resonanc… more
Date: March 21, 2012
Creator: Puccio, Eugenia Maria Teresa Irene & /SLAC, /Warwick U.
Partner: UNT Libraries Government Documents Department
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Electron Generation and Transport in Intense Relativistic Laser-Plasma Interactions Relevant to Fast Ignition ICF

Description: The reentrant cone approach to Fast Ignition, an advanced Inertial Confinement Fusion scheme, remains one of the most attractive because of the potential to efficiently collect and guide the laser light into the cone tip and direct energetic electrons into the high density core of the fuel. However, in the presence of a preformed plasma, the laser energy is largely absorbed before it can reach the cone tip. Full scale fast ignition laser systems are envisioned to have prepulses ranging between … more
Date: April 21, 2010
Creator: Ma, T
Partner: UNT Libraries Government Documents Department
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Nuclear magnetic resonance studies of quadrupolar nuclei and dipolar field effects

Description: Experimental and theoretical research conducted in two areas in the field of nuclear magnetic resonance (NMR) spectroscopy is presented: (1) studies of the coherent quantum-mechanical control of the angular momentum dynamics of quadrupolar (spin I > 1/2) nuclei and its application to the determination of molecular structure; and (2) applications of the long-range nuclear dipolar field to novel NMR detection methodologies.The dissertation is organized into six chapters. The first two chapters… more
Date: December 21, 2004
Creator: Urban, Jeffry Todd
Partner: UNT Libraries Government Documents Department
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THERMOLUMINESCENCE SPECTRA AND ACTIVATION ENERGIES FOR AROMATIC AMINO ACIDS, TRYPSIN, AND SPORES OF BACILLUS MEGATERIUM

Description: The theory of thermoluminescence is reviewed. The spectral distribution of thermoluminescence and the activation energies associated with peaks of the glow curves were determined for samples of aromatic amino acids, trypsin, and spores of Bacillus megaterium irradiated by a Co/sup 60/ gamma source. All of the substances, except phenylalanine, exhibited a readily observable long-lived glow that persisted up to at least 2 hr following irradiation. Possible reaction mechanisms in the production of… more
Date: June 21, 1963
Creator: Weinberg, C. J.; Carter, J. G.; Nelson, D. R. & Birkhoff, R. D.
Partner: UNT Libraries Government Documents Department
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Towards Chip Scale Liquid Chromatography and High Throughput Immunosensing

Description: This work describes several research projects aimed towards developing new instruments and novel methods for high throughput chemical and biological analysis. Approaches are taken in two directions. The first direction takes advantage of well-established semiconductor fabrication techniques and applies them to miniaturize instruments that are workhorses in analytical laboratories. Specifically, the first part of this work focused on the development of micropumps and microvalves for controlled f… more
Date: September 21, 2000
Creator: Ni, J.
Partner: UNT Libraries Government Documents Department
open access

Sum-frequency spectroscopic studies: I. Surface melting of ice, II. Surface alignment of polymers

Description: Surface vibrational spectroscopy via infrared-visible sum-frequency generation (SFG) has been established as a useful tool to study the structures of different kinds of surfaces and interfaces. This technique was used to study the (0001) face of hexagonal ice (Ih). SFG spectra in the O-H stretch frequency range were obtained at various sample temperatures. For the vapor(air)/ice interface, the degree of orientational order of the dangling OH bonds at the surface was measured as a function of te… more
Date: December 21, 2000
Creator: Wei, Xing
Partner: UNT Libraries Government Documents Department
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Transition Metal Complexes of Cr, Mo, W and Mn Containing {eta}{sup 1}(S)-2,5-Dimethylthiophene, Benzothiophene and Dibenzothiophene Ligands

Description: The UV photolysis of hexanes solutions containing the complexes M(CO){sub 6} (M=Cr, Mo, W) or CpMn(CO){sub 3} (Cp={eta}{sup 5}-C{sub 5}H{sub 5}) and excess thiophene (T{sup *}) (T{sup *}=2,5-dimethylthiophene (2,5-Me{sub 2}T), benzothiophene (BT), and dibenzothiophene (DBT)) produces the {eta}{sup 1}(S)-T{sup *} complexes (CO){sub 5}M({eta}{sup 1}(S)-T{sup *}) 1-8 or Cp(CO){sub 2}Mn({eta}{sup 1}(S)-T{sup *})9-11, respectively. However, when T{sup *}=DBT, and M=Mo, a mixture of two products resu… more
Date: September 21, 2000
Creator: Reynolds, M.
Partner: UNT Libraries Government Documents Department
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