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Kinetic Studies of the Reactions Occurring Between Tungsten and Gases at Low Pressure and High Temperatures

Description: Oxygen, nitrogen, and nitric oxide gases were passed through a system consisting of a tungsten filament, an ion gauge, and a mass spectrometer. The ion gauge recorded total pressures and the spectrometer recorded partlal pressures of O/sub 2/, N/sub 2/, NO, CO, COa, and H/sub 2/O. From the way these pressures changed with filamert temperature, the rates of conversion of O/sub 2/ to volatile tungsten oxides and O, and of NO to volatile tungsten oxides N/sub 2/ , O/sub 2/, and O were computed. Th… more
Date: April 1, 1962
Creator: Anderson, H. U.
Partner: UNT Libraries Government Documents Department
open access

Heavy-Ion Elastic Scattering

Description: The elastic scattering of C/sup 12/ ions from Ar, Fe, Ni, Ag/sup 107/ In, and Ta was measured as a function of angle, at a laboratory-system energy of 124.5 Mev with the Berkeley heavy-ion linear accelerator. The experimental equipment and techniques are discussed. The angular distributions show the same general behavior as previous heavy-ion elastic scattering experiments. The experimental data were analyzed with the semiclassical Blair model as modified by McIntyre. Very good agreement with e… more
Date: April 17, 1961
Creator: Alster, Jonas
Partner: UNT Libraries Government Documents Department
open access

The History of the Bill J. Priest Institute for Economic Development of the Dallas County Community College District

Description: The Bill J. Priest Institute for Economic Development is an entity created in the Dallas County Community College District to serve the community in workforce and economic development. The history of the Priest Institute over the last ten years parallels and illustrates the commitment of community colleges nationally to workforce and economic development. The history also reflects similar goals and trends within the state of Texas and, particularly, in the city of Dallas. The Priest Institute i… more
Date: April 1994
Creator: Hughes, Martha
Partner: UNT Libraries
open access

A search for particle dark matter using cryogenic germanium and silicon detectors in the one- and two- tower runs of CDMS-II at Soudan

Description: Images of the Bullet Cluster of galaxies in visible light, X-rays, and through gravitational lensing confirm that most of the matter in the universe is not composed of any known form of matter. The combined evidence from the dynamics of galaxies and clusters of galaxies, the cosmic microwave background, big bang nucleosynthesis, and other observations indicates that 80% of the universe's matter is dark, nearly collisionless, and cold. The identify of the dar, matter remains unknown, but weakly … more
Date: April 1, 2008
Creator: Ogburn, Reuben Walter, IV
Partner: UNT Libraries Government Documents Department
open access

Implementation of an interactive matching scheme for the Kapchinskij-Vladimirskij equations in the WARP code

Description: The WARP code is a robust electrostatic particle-in-cell simulation package used to model charged particle beams with strong space-charge forces. A fundamental operation associated with seeding detailed simulations of a beam transport channel is to generate initial conditions where the beam distribution is matched to the structure of a periodic focusing lattice. This is done by solving for periodic, matched solutions to a coupled set of ODEs called the Kapchinskij-Vladimirskij (KV) envelope equ… more
Date: April 15, 2008
Creator: Chilton, Sven H.
Partner: UNT Libraries Government Documents Department
open access

WW production cross section measurement and limits on anomalous trilinear gauge couplings at sqrt(s) = 1.96-TeV

Description: The cross section for WW production is measured and limits on anomalous WW{gamma} and WWZ trilinear gauge couplings are set using WW {yields} ee/e{mu}/{mu}{mu} events collected by the Run II D0 detector at the Fermilab Tevatron Collider corresponding to 1 fb{sup -1} of integrated luminosity at {radical}s = 1.96 TeV. Across the three final states, 108 candidate events are observed with 40.8 {+-} 3.8 total background expected, consistent with {sigma}(p{bar p} {yields} WW) = 11.6 {+-} 1.8(stat) {+… more
Date: April 1, 2008
Creator: Cooke, Michael P. & U., /Rice
Partner: UNT Libraries Government Documents Department
open access

Search for MSSM Higgs Boson Production in Proton Anti-Proton Collisions, with a Higgs Decaying into Taus

Description: We present a search for the production of neutral Higgs bosons in association with bottom quarks in p{bar p} collisions at {radical}s = 1.96 TeV. The cross section for this process is enhanced in many extensions of the Standard Model (SM), such as in its Minimal Supersymmetric extension (MSSM) at large tan {beta}. The data, corresponding to a recorded integrated luminosity of 1 fb{sup -1}, were collected with the D0 detector at the Fermilab Tevatron Collider. In the absence of a signal a 95% C.… more
Date: April 1, 2008
Creator: Svoisky, Peter V. & U., /Notre Dame
Partner: UNT Libraries Government Documents Department
open access

Cross section measurements for quasi-elastic neutrino-nucleus scattering with the MINOS near detector

Description: The Main Injector Neutrino Oscillation Search (MINOS) is a long baseline neutrino oscillation experiment based at the Fermi National Accelerator Laboratory (FNAL) in Chicago, Illinois. MINOS measures neutrino interactions in two large iron-scintillator tracking/sampling calorimeters; the Near Detector on-site at FNAL and the Far Detector located in the Soudan mine in northern Minnesota. The Near Detector has recorded a large number of neutrino interactions and this high statistics dataset can b… more
Date: April 1, 2008
Creator: Dorman, Mark Edward & London, /University Coll.
Partner: UNT Libraries Government Documents Department
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Measurement of Inclusive Jet Cross Sections in Z/gamma*(->e+e-) + jets Production in ppbar Collisions at s**(1/2) = 1.96 TeV with the CDF Detector

Description: This Ph.D. thesis presents the measurement of inclusive jet cross sections in Z/{gamma}* {yields} e{sup +}e{sup -} events using 1.7 fb{sup -1} of data collected by the upgraded CDF detector during the Run II of the Tevatron. The Midpoint cone algorithm is used to search for jets in the events after identifying the presence of a Z/{gamma}* boson through the reconstruction of its decay products. The measurements are compared to next-to-LO (NLO) pQCD predictions for events with one and two jets in… more
Date: April 1, 2008
Creator: Salto Bauza, Oriol
Partner: UNT Libraries Government Documents Department
open access

Evidence for electroweak top quark production in proton-antiproton collisions at s**(1/2) = 1.96 TeV

Description: We present the first evidence for electroweak single top quark production using nearly 1 fb{sup -1} of Tevatron Run II data at {radical}s = 1.96 TeV. We select single-top-like data events in the lepton+jets decay channel and separate them from backgrounds using the matrix element analysis method. This technique uses leading order matrix elements to compute an event probability for both signal and background hypotheses. Using the expected signal acceptance, background, and observed data we measu… more
Date: April 1, 2007
Creator: Gadfort, Thomas & /Washington U., Seattle
Partner: UNT Libraries Government Documents Department
open access

Desulfurization of coal model compounds and coal liquids.

Description: Most US coals contain sulfur concentrations that prevent their being burned without some form of sulfur removal. Current coal-cleaning technology can only remove the fairly reactive pyritic (inorganic) and aliphatic (organic) sulfur. A process which removes the more refractory hetero-aromatic sulfur could substantially increase the amount of coal reserves amenable to chemical cleaning. Sodium metal dispersions convert refractor model compounds into lighter desulfurized products and non-volatile… more
Date: April 1, 1979
Creator: Wrathall, James Anthony & Peterson, Eugene E.
Partner: UNT Libraries Government Documents Department
open access

Scientific Reality in C. P. Snow

Description: Twentieth-century science proves that heredity and environment function similarly in all named living species except one--Homo sapiens. Man alone, through his intellect, forms language and culture, thereby affecting his environment so that he participates in the process of his own creation. This participation so links humans that each man extends outside himself creating of the human race a single, whole fabric. C. P. Snow, aware of this communal reality, notes the present lack of communication… more
Date: April 1979
Creator: Damico, Dorothy Trageser
Partner: UNT Libraries
open access

Mental Status, Intellectual, and Mood States Associated with Environmental Illness Patients

Description: The purpose of the present study was to begin development of a psychological profile for environmentally ill patients. Existing psychiatric labels are unable to encompass these patients. Test scores were drawn from a pool of 89 patients whose environmental exposures were verified by the presence of toxins in the blood serum. A Mental Status Exam, a Wechsler Adult Intelligence Scale-Revised screen, and the Profile of Mood States were administered. Results indicate a primary pattern which is sign… more
Date: April 1991
Creator: Fincher, Cynthia Ellen
Partner: UNT Libraries
open access

The Atheism of Mark Twain: The Early Years

Description: Many Twain scholars believe that his skepticism was based on personal tragedies of later years. Others find skepticism in Twain's work as early as The Innocents Abroad. This study determines that Twain's atheism is evident in his earliest writings. Chapter One examines what critics have determined Twain's religious sense to be. These contentions are discussed in light of recent publications and older, often ignored, evidence of Twain' s atheism. Chapter Two is a biographical look at Twain's lit… more
Date: April 1986
Creator: Britton, Wesley A. (Wesley Alan)
Partner: UNT Libraries
open access

Soft x-ray streak camera for laser fusion applications

Description: This thesis reviews the development and significance of the soft x-ray streak camera (SXRSC) in the context of inertial confinement fusion energy development. A brief introduction of laser fusion and laser fusion diagnostics is presented. The need for a soft x-ray streak camera as a laser fusion diagnostic is shown. Basic x-ray streak camera characteristics, design, and operation are reviewed. The SXRSC design criteria, the requirement for a subkilovolt x-ray transmitting window, and the result… more
Date: April 1981
Creator: Stradling, Gary L.
Partner: UNT Libraries Government Documents Department
open access

Chemistry of coal model compounds: cleavage of aliphatic bridges between aromatic nuclei catalyzed by Lewis acids.

Description: The condensed polynuclear aromatic clusters of coal are believed to be linked principally by straight-chain aliphatic bridges varying from 0 to 4 carbon atoms in length and the cleavage of these linkages is expected to be an important step in the coal liquefaction process. This study focuses on the means by which Lewis acid catalysts, specifically AlCl/sub 3/ and ZnCl/sub 2/, promote the cleavage of these linkages. To facilitate product identification and interpretation of reaction mechanisms, … more
Date: April 1, 1978
Creator: Taylor, N. D.
Partner: UNT Libraries Government Documents Department
open access

The application of psoralens to the study of DNA structure, function and dynamics

Description: A series of six nitroxide spin-labeled psoralens were designed, synthesized and tested as probes for DNA dynamics. The synthesis of these spin-labeled psoralen derivatives and their photoreactivity with double-stranded DNA fragments is described. The spin labels (nitroxides) were demonstrated to survive the uv irradiation required to bind the probe to the target DNA. EPR spectra of the photobound spin-labels indicate that they do not wobble with respect to the DNA on the time-scales investigate… more
Date: April 1, 1991
Creator: Spielmann, P. H.
Partner: UNT Libraries Government Documents Department
open access

Relative Yields of Nitrogen-17 Produced by 190-Mev Deuteron Bombardment

Description: "Yields of N¹⁷ relative to that produced in LiF have been measured in the 190-Mev deflected deuteron and the 380-Mev alpha beams of the 184-inch synchrocyclotron. The measurements have been performed in all the light elements from 0 through V, with the exception of Sc and the noble gases. In addition, yields were measured in the separated isotopes of Mg...Comparisons are made with other types of yield studies performed with neutrons and protons, and the areas of agreement are noted."
Date: April 13, 1955
Creator: Chupp, Warren William
Partner: UNT Libraries Government Documents Department
open access

The Masses of Identified Positive Heavy Mesons

Description: The following report describes the charged secondary particles from all presently known decay modes of positive K mesons that have been identified, and the masses of the primaries measured by the momentum-range method.
Date: April 5, 1956
Creator: Peterson, James Ray
Partner: UNT Libraries Government Documents Department
open access

Interactions of Negative K Mesons in Flight in Nuclear Emulsion

Description: The following report discusses a survey of seventy-seven interactions of K- mesons in flight in nuclear emulsion with seven decays in flight, and finding four inelastic scatterings.
Date: April 30, 1957
Creator: Featherston, Frank Hunter
Partner: UNT Libraries Government Documents Department
open access

The effect of rhenium, sulfur and alumina on the conversion of hydrocarbons over platinum single crystals: Surface science and catalytic studies

Description: Conversion reactions of hydrocarbons over Pt-Re model catalyst surfaces modified by sulfur and alumina have been studied. A plasma deposition source has been developed to deposit Pt, Re, and Al on metal substrates variable coverage in ultrahigh vacuum without excessive heating. Conversion of n-hexane was performed over the Re-covered Pt and Pt-covered Re surfaces. The presence of the second metal increased hydrogenolysis activity of both Pt-Re surfaces. Addition of sulfur on the model Catalyst … more
Date: April 1, 1992
Creator: Kim, C.
Partner: UNT Libraries Government Documents Department
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