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Credibility and Performance Changes in Older Persons

Description: This paper discusses the irreversible decrement model and explores credibility and performance changes in older persons through a study conducted with 300 residents of the Dallas/Fort Worth area. Phyllis L. Jones performs a literature review before delving into the methodology, process, and results of the study.
Date: September 1989
Creator: Jones, Phyllis L.
Partner: UNT Libraries
open access

The Effects of Just World Beliefs and Behavioral vs. Characterological Self-Blame on College Student’s Functioning Following Parental Divorce

Description: This paper discusses the impact of self-blame on college students who have experienced parental divorce and determines whether separating this blame into behavioral and characterological manifestations can provide useful information for research purposes. Bryce E. Taylor explains the study that was conducted with 220 female college students who completed questionnaires for the project, and the results of the study.
Date: September 1991
Creator: Taylor, Bryce E.
Partner: UNT Libraries
open access

Beam Diagnosis and Lattice Modeling of the Fermilab Booster

Description: A realistic lattice model is a fundamental basis for the operation of a synchrotron. In this study various beam-based measurements, including orbit response matrix (ORM) and BPM turn-by-turn data are used to verify and calibrate the lattice model of the Fermilab Booster. In the ORM study, despite the strong correlation between the gradient parameters of adjacent magnets which prevents a full determination of the model parameters, an equivalent lattice model is obtained by imposing appropriate c… more
Date: September 1, 2005
Creator: Huang, Xiaobiao
Partner: UNT Libraries Government Documents Department
open access

Experimental Studies of Laser-Induced Breakdown in Transparent Dielectrics

Description: The mechanisms by which transparent dielectrics damage when exposed to high power laser radiation has been of scientific and technological interest since the invention of the laser. In this work, a set of three experiments are presented which provide insight into the damage initiation mechanisms and the processes involved in laser-induced damage. Using an OPO (optical parametric oscillator) laser, we have measured the damage thresholds of deuterated potassium dihydrogen phosphate (DKDP) from th… more
Date: September 23, 2003
Creator: Carr, C W
Partner: UNT Libraries Government Documents Department
open access

A High-Energy, Ultrashort-Pulse X-Ray System for the Dynamic Study of Heavy, Dense Materials

Description: Thomson-scattering based x-ray radiation sources, in which a laser beam is scattered off a relativistic electron beam resulting in a high-energy x-ray beam, are currently being developed by several groups around the world to enable studies of dynamic material properties which require temporal resolution on the order of tens of femtoseconds to tens of picoseconds. These sources offer pulses that are shorter than available from synchrotrons, more tunable than available from so-called Ka sources, … more
Date: September 17, 2004
Creator: Gibson, D J
Partner: UNT Libraries Government Documents Department
open access

The Cryogenic Dark Matter Search (CDMS-II) Experiment: First Results from the Soudan Mine

Description: There is an abundance of evidence that the majority of the mass of the universe is in the form of non-baryonic non-luminous matter that was non-relativistic at the time when matter began to dominate the energy density. Weakly Interacting Massive Particles, or WIMPs, are attractive cold dark matter candidates because they would have a relic abundance today of {approx}0.1 which is consistent with precision cosmological measurements. WIMPs are also well motivated theoretically. Many minimal supers… more
Date: September 1, 2004
Creator: Chang, Clarence Leeder
Partner: UNT Libraries Government Documents Department
open access

A Search for Supersymmetric Higgs Bosons in the Di-tau Decay Mode in Proton - Anti-proton Collisions at 1.8 TeV

Description: A search for directly produced Supersymmetric Higgs Bosons has been performed in the di-tau decay channel in 86.3 {+-} 3.5 pb{sup -1} of data collected by CDF during Run1b at the Tevatron. They search for events where one tau decays to an electron and the other tau decays hadronically. They perform a counting experiment and set limits on the cross section for Higgs production in the high tan {beta} region of the m{sub A}-tan {beta} plane. For a benchmark parameter space point where m{sub A} = 1… more
Date: September 1, 2003
Creator: Connolly, Amy Lynn
Partner: UNT Libraries Government Documents Department
open access

Development of workflow planning software and a tracking study of the decay B+- --> J / Psi at the D0 Experiment

Description: A description of the development of the mc{_}runjob software package used to manage large scale computing tasks for the D0 Experiment at Fermilab is presented, along with a review of the Digital Front End Trigger electronics and the software used to control them. A tracking study is performed on detector data to determine that the D0 Experiment can detect charged B mesons, and that these results are in accordance with current results. B mesons are found by searching for the decay channel B{sup … more
Date: September 1, 2003
Creator: Evans, David Edward
Partner: UNT Libraries Government Documents Department
open access

Kinetics of (beta)(right arrow)(delta) Solid-Solid Phase Transition of HMX

Description: In order to calculate the kinetic parameters from DSC data, we have used the generally accepted methods of Bershtein [13]. We have calculated the rate constants for 4 temperatures and the activation energy based on the shift in the transition temperature, {beta} {yields} {delta} for HMX. The values of E{sub a} from this work is 402 kJ/mol compared to previous results by Brill [9] of 204 kJ/mol. Brill and associates measured the phase transition of HMX using FTIR, sodium chloride plates and sili… more
Date: September 1, 2000
Creator: Weese, R K
Partner: UNT Libraries Government Documents Department
open access

Carbon doping of III-V compound semiconductors

Description: Focus of the study is C acceptor doping of GaAs, since C diffusion coefficient is at least one order of magnitude lower than that of other common p-type dopants in GaAs. C ion implantation results in a concentration of free holes in the valence band < 10% of that of the implanted C atoms for doses > 10{sup 14}/cm{sup 2}. Rutherford backscattering, electrical measurements, Raman spectroscopy, and Fourier transform infrared spectroscopy were amonth the techniques used. Ga co-implantation increase… more
Date: September 1, 1994
Creator: Moll, A. J.
Partner: UNT Libraries Government Documents Department
open access

Laser trapping of {sup 21}Na atoms

Description: This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trap… more
Date: September 1, 1994
Creator: Lu, Zheng-Tian
Partner: UNT Libraries Government Documents Department
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Focus on NIF September 2001

Description: As of the end of August, the National Ignition Facility (NIF) is satisfactorily meeting its technical performance, cost and schedule milestones. Hensel Phelps Construction Company (HPCC) turned over the Laser Building to the Beampath Infrastructure System (BIS) Commissioning and Operations team for beneficial occupancy.
Date: September 5, 2001
Creator: Warner, B
Partner: UNT Libraries Government Documents Department
open access

Straddle-packer determination of the vertical distribution of hydraulic properties in the Snake River Plain Aquifer at well USGS-44, Idaho Chemical Processing Plant, INEL

Description: Many of the monitor wells that penetrate the upper portion of the Snake River Plain aquifer at the Idaho National Engineering Laboratory (INEL) are open over large intervals that include multiple water-bearing zones. Most of these wells are equipped with dedicated submersible pumps. Water of varying quality from different water-bearing zones is mixed within the wells. The hydrologic properties of individual water bearing zones are difficult to determine. Water quality and water-level data on or… more
Date: September 23, 1994
Creator: Monks, J. I.
Partner: UNT Libraries Government Documents Department
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The Mirrortron experiment: A proof of principle test for a method of generating high transient potentials

Description: The Mirrortron is a concept in which heavy ions are accelerated by a large local transient space potential that is produced in a hot electron plasma. The purpose of this experiment is to begin a proof of principle experiment to investigate the feasibility of producing this space potential and its associated electric field. If a large magnetic field is suddenly generated in a hot electron plasma with a loss-cone distribution, then potentials on the order of the electron temperature are expected.… more
Date: September 1, 1993
Creator: Douglass, S. R.
Partner: UNT Libraries Government Documents Department
open access

Application of an Electrochemical Quartz Crystal Microbalance to the study of electrocatalytic films

Description: The EQCM was used to study the deposition and composition of electrodeposited pure PbO{sub 2} and Bi-doped PbO{sub 2} active toward anodic oxygen-transfer reactions. Within the doped films, Bi is incorporated as Bi{sup +5} in the form of BiO{sub 2}A, where A is ClO{sub 4}{sup {minus}} or NO{sub 3}{sup {minus}}. For deposition of these 2 materials, changes in hydration between the Au oxide and the depositing film resulted in higher mass-to-charge ratios. XRD and XPS were used to study the films;… more
Date: September 1, 1993
Creator: Gordon, J. S., Jr.
Partner: UNT Libraries Government Documents Department
open access

NIF program management

Description: No Description Available.
Date: September 15, 2000
Creator: Carpenter, J & Warner, B
Partner: UNT Libraries Government Documents Department
open access

The synthesis and structural characterization of novel transition metal fluorides

Description: High purity KMF{sub 6} and K{sub 2}MF{sub 6} salts (M = Mo,Re, Ru, Os, Ir, Pt) are obtained from reduction hexafluorides. A rhombohedral unit cell is observed for KReF{sub 6}. Fluoride ion capture by Lewis acids from the hexafluorometallate (IV) salts affords high purity tetrafluorides for M = Mo, Re, Ru, Os, and Pd. The structure of RuF{sub 4} is determined from X-ray synchrotron and neutron powder data. Unit cells based on theorthorhombic PdF{sub 4} type cell are derived from X-ray powder dat… more
Date: September 1, 1992
Creator: Casteel, W. J. Jr.
Partner: UNT Libraries Government Documents Department
open access

CCM Continuity Constraint Method: A finite-element computational fluid dynamics algorithm for incompressible Navier-Stokes fluid flows

Description: As the field of computational fluid dynamics (CFD) continues to mature, algorithms are required to exploit the most recent advances in approximation theory, numerical mathematics, computing architectures, and hardware. Meeting this requirement is particularly challenging in incompressible fluid mechanics, where primitive-variable CFD formulations that are robust, while also accurate and efficient in three dimensions, remain an elusive goal. This dissertation asserts that one key to accomplishin… more
Date: September 1, 1993
Creator: Williams, P. T.
Partner: UNT Libraries Government Documents Department
open access

NIF frequently asked questions

Description: The Stockpile Stewardship Program is an initiative to maintain the nuclear deterrent of the United States in the post-Cold War era. It is based on the maintenance of our stockpile through an ongoing process of surveillance, assessment, refurbishment, and recertification, without nuclear testing. At the heart of the SSP is an attempt to bring advanced experimental and computational tools to bear on the evaluation and certification of the stockpile itself; these advanced scientific capabilities a… more
Date: September 15, 2000
Creator: Carpenter, J & Warner, B
Partner: UNT Libraries Government Documents Department
open access

Quantitative evaluation of material composition of composites using x-ray energy-dispersive NDE technique

Description: This technique worked well for determining the thickness and densities for composite components having the higher linear attenuation coefficient; it accurately determined thickness of epoxy-resin and Al metal, and the denisty of bone, to {le} 4% in the graphite-epoxy, bone-plexiglas, and Al-Al corrosion composites. Accuracy is dictated by the magnitude and uncertainty of the linear attenuation coefficient. Use of Ge detector and multichannel analyzer are limited by inspection time (1 day for po… more
Date: September 1, 1993
Creator: Ting, J.
Partner: UNT Libraries Government Documents Department
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The incongruent melting and melt textured solidification process of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8}

Description: The melting and solidification was studied using in-situ high temperature XRD from melting point to 900{degree}C in 0.2, 0.1, 0.02 atm O{sub 2} and pure N{sub 2}. The incongruent melting point of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} was lowered by decreasing the partial O{sub 2} pressure from 870C (in .2 atm O{sub 2}) to 830C (in pure N{sub 2} atmosphere). As temperature was increased the incongruent melting of Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} followed a phase sequence in which (Ca, Sr)Cu… more
Date: September 1, 1993
Creator: Polonka, J.
Partner: UNT Libraries Government Documents Department
open access

NIF and science

Description: The National Ignition Facility (NIF) will have many uses besides its primary mission in the US Department of Energy's Stockpile Stewardship Program. It will provide a broad array of applications to basic science, and will also play an important role in the development of commercial fusion energy.
Date: September 15, 2000
Creator: Carpenter, J & Warner, B
Partner: UNT Libraries Government Documents Department
open access

Reduction of plyatomic ion interferences in indictively coupled plasma mass spectrometry with cryogenic desolvation

Description: A desolvation scheme for introducing aqueous and organic samples into an argon inductively coupled plasma is described; the aerosol generated by nebulizer is heated (+140 C) and cooled ({minus}80 C) repeatedly, and the dried aerosol is then injected into the mass spectrometer. Polyatomic ions are greatly suppressed. This scheme was validated with analysis of seawater and urine reference samples. Finally, the removal of organic solvents by cryogenic desolvation was studied.
Date: September 1, 1993
Creator: Alves, L. C.
Partner: UNT Libraries Government Documents Department
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