Degree Department

Degree Discipline

Degree Level

28 Matching Results

Results open in a new window/tab.

48Ti(n,xnypz ag) reactions for neutron energies up to 250 MeV (open access)

48Ti(n,xnypz ag) reactions for neutron energies up to 250 MeV

Cross section measurements were made of prompt {gamma}-ray production as a function of incident neutron energy on a {sup 48}Ti sample. Partial {gamma}-ray cross sections for transitions in {sup 45--48}Ti, {sup 44--48}Sc, {sup 42--45}Ca, {sup 41--44}K, and {sup 41--42}Ar have been determined. Energetic neutrons were delivered by the Los Alamos National Laboratory spallation neutron source located at the LANSCE/WNR facility. The prompt-reaction {gamma} rays were detected with the large-scale Compton-suppressed germanium array for neutron induced excitations (GEANIE). Neutron energies were determined by the time-of-flight technique. The {gamma}-ray excitation functions were converted to partial {gamma}-ray cross sections taking into account the dead-time correction, target thickness, detector efficiency and neutron flux (monitored with an in-line fission chamber). The data will be presented for neutron energies between 1 to 250 MeV. These results are compared with model calculations which include compound nuclear and pre-equilibrium emission.
Date: October 11, 2004
Creator: Dashdorj, D.; Garrett, P. E.; Becker, J. A.; Bernstein, L. A.; Cooper, J. R.; Devlin, M. et al.
Object Type: Article
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 106, No. 165, Ed. 1 Monday, October 11, 2004 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 165, Ed. 1 Monday, October 11, 2004

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: October 11, 2004
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Sun (Alvin, Tex.), Vol. 114, No. 82, Ed. 1 Monday, October 11, 2004 (open access)

The Alvin Sun (Alvin, Tex.), Vol. 114, No. 82, Ed. 1 Monday, October 11, 2004

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: October 11, 2004
Creator: Schwind, Jim & Looby, Edward
Object Type: Newspaper
System: The Portal to Texas History
Application of Ab Initio and CALPHAD Thermodynamics to Mo-Ta-W Alloys (open access)

Application of Ab Initio and CALPHAD Thermodynamics to Mo-Ta-W Alloys

None
Date: October 11, 2004
Creator: Turchi, P. A.; Drchal, V.; Kudrnovsky, J.; Colinet, C.; Kaufman, L. & Liu, Z.
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 83, No. 312, Ed. 1 Monday, October 11, 2004 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 83, No. 312, Ed. 1 Monday, October 11, 2004

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: October 11, 2004
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Discussion: Reporting and calibration of post-bomb 14C data (open access)

Discussion: Reporting and calibration of post-bomb 14C data

The definitive paper by Stuiver and Polach (1977) established the conventions for reporting of {sup 14}C data for chronological and geophysical studies based on the radioactive decay of {sup 14}C in the sample since the year of sample death or formation. Several ways of reporting {sup 14}C activity levels relative to a standard were also established, but no specific instructions were given for reporting nuclear weapons testing (post-bomb) {sup 14}C levels in samples. Because the use of post-bomb {sup 14}C is becoming more prevalent in forensics, biology, and geosciences, a convention needs to be adopted. We advocate the use of fraction modern with a new symbol F{sup 14}C to prevent confusion with the previously used Fm, which may or may not have been fractionation corrected. We also discuss the calibration of post-bomb {sup 14}C samples and the available datasets and compilations, but do not give a recommendation for a particular dataset.
Date: October 11, 2004
Creator: Reimer, P J; Brown, T A & Reimer, R W
Object Type: Article
System: The UNT Digital Library

Doctoral Recital: 2004-10-11 – Karl Kemm, horn

Recital presented at the UNT College of Music Recital Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date: October 11, 2004
Creator: Kemm, Karl
Object Type: Sound
System: The UNT Digital Library
[Email from Bob Gray to Charles Francis, October 11, 2004] (open access)

[Email from Bob Gray to Charles Francis, October 11, 2004]

An email from Bob Gray to Charles C. Francis about a clipping from the San Francisco Chronicle and Francis' progress with gay and lesbian rights.
Date: October 11, 2004
Creator: Gray, Bob
Object Type: Letter
System: The UNT Digital Library
Emerging Energy-Efficient Technologies in Buildings Technology Characterizations for Energy Modeling (open access)

Emerging Energy-Efficient Technologies in Buildings Technology Characterizations for Energy Modeling

The energy use in America's commercial and residential building sectors is large and growing. Over 38 quadrillion Btus (Quads) of primary energy were consumed in 2002, representing 39% of total U.S. energy consumption. While the energy use in buildings is expected to grow to 52 Quads by 2025, a large number of energy-related technologies exist that could curtail this increase. In recent years, improvements in such items as high efficiency refrigerators, compact fluorescent lights, high-SEER air conditioners, and improved building shells have all contributed to reducing energy use. Hundreds of other technology improvements have and will continue to improve the energy use in buildings. While many technologies are well understood and are gradually penetrating the market, more advanced technologies will be introduced in the future. The pace and extent of these advances can be improved through state and federal R&D. This report focuses on the long-term potential for energy-efficiency improvement in buildings. Five promising technologies have been selected for description to give an idea of the wide range of possibilities. They address the major areas of energy use in buildings: space conditioning (33% of building use), water heating (9%), and lighting (16%). Besides describing energy-using technologies (solid-state lighting and geothermal …
Date: October 11, 2004
Creator: Hadley, SW
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Monday, October 11, 2004 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Monday, October 11, 2004

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: October 11, 2004
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
FEPs Screening of Processes and Issues in Drip Shield and Waste Package Degradation (open access)

FEPs Screening of Processes and Issues in Drip Shield and Waste Package Degradation

The purpose of this report is to evaluate and document the inclusion or exclusion of features, events and processes (FEPs) with respect to drip shield and waste package modeling used to support the Total System Performance Assessment for License Application (TSPA-LA). Thirty-three FEPs associated with the waste package and drip shield performance have been identified (DTN: MO0407SEPFEPLA.000 [DIRS 170760]). A screening decision, either ''included'' or ''excluded,'' has been assigned to each FEP, with the technical bases for screening decisions, as required by the Nuclear Regulatory Commission (NRC) in 10 CFR 63.114 (d, e, and f) [DIRS 156605]. The FEPs analyses in this report address issues related to the degradation and potential failure of the drip shield and waste package over the post closure regulatory period of 10,000 years after permanent closure. For included FEPs, this report summarizes the disposition of the FEP in TSPA-LA. For excluded FEPs, this report provides the technical bases for the screening arguments for exclusion from TSPA-LA. The analyses are for the TSPA-LA base-case design (BSC 2004 [DIRS 168489]), where a drip shield is placed over the waste package without backfill over the drip shield (BSC 2004 [DIRS 168489]). Each FEP includes one or more specific …
Date: October 11, 2004
Creator: Mon, K.
Object Type: Report
System: The UNT Digital Library
Frequency map analysis of nonlinear dynamics in the NLC main damping rings (open access)

Frequency map analysis of nonlinear dynamics in the NLC main damping rings

To avoid radiation damage, the acceptance of linear collider damping rings must be large enough that injection efficiency close to 100 percent can be achieved. Survival plots based on tracking particles in the NLC Main Damping Ring lattice suggest a dynamic aperture with some margin over the specified injected beam size and energy spread. Here, we apply Frequency Map Analysis to give a more detailed picture of the dynamical stability of particle trajectories in the presence of lattice nonlinearities arising from the sextupoles and the damping wiggler. The techniques that we use are of general applicability to nonlinear elements in beamlines, and in particular will be used for analysis of wiggler effects in future damping ring designs.
Date: October 11, 2004
Creator: Wolski, Andrzej; Venturini, Marco; Wan, Weishi & Marks, Steve
Object Type: Report
System: The UNT Digital Library
Hard X-ray Optics for Astronomy and the Laboratory (open access)

Hard X-ray Optics for Astronomy and the Laboratory

The hard X-ray regime (10-100 keV) remains one of the last unexplored areas of astronomy. During the next decade, several major observatories will open this new frontier, providing insight into black hole formation, nucleosynthesis and the physics that governs the most energetic quasars. The telescopes rely on grazing incidence optics coated with multilayers, and will require at wavelength calibration of the angular resolution of the mirrors and the reflectivity of their coatings-a task best performed at synchrotron facilities. As mirror fabrication and multilayer development for astronomy has progressed, other applications of these hard X-rays optics has emerged, ranging from radionuclide imaging for biomedical research to collimator optics for X-ray sources to target characterization and diagnostic imaging for the National Ignition Facility (NIF). The resolution, field of view (FOV) and throughput of these systems make them interesting candidates for adaptation to synchrotron beamlines, acting as collimator or collector elements or focusing elements for microscopy.
Date: October 11, 2004
Creator: Pivovaroff, M
Object Type: Article
System: The UNT Digital Library
High pT hadron spectra at RHIC: an overview (open access)

High pT hadron spectra at RHIC: an overview

Recent results on high transverse momentum (p{sub T}) hadron production in p+p, d+Au and Au+Au collisions at the Relativistic Heavy Ion Collider (RHIC) are reviewed. Comparison of the nuclear modification factors, R{sub dAu}(p{sub T}) and R{sub AA}(p{sub T}), demonstrates that the large suppression in central Au+Au collisions is due to strong final-state effects. Theoretical models which incorporate jet quenching via gluon Bremsstrahlung in the dense partonic medium that is expected in central Au+Au collisions at ultra-relativistic energies are shown to reproduce the shape and magnitude of the observed suppression over the range of collision energies so far studied at RHIC.
Date: October 11, 2004
Creator: Klay, J L
Object Type: Article
System: The UNT Digital Library
Lattice design for an ILC damping ring with 3 km circumference (open access)

Lattice design for an ILC damping ring with 3 km circumference

We describe a simple lattice that meets the specifications for the damping times and horizontal and longitudinal emittances for the International Linear Collider (ILC) damping rings. The circumference of a little over 3 km leads to a bunch spacing of around 3 ns, which will require advances in kicker technology for injection and extraction. We present the lattice design, and initial results of studies of the acceptance and collective effects. With the high bunch charge and close spacing, the ion and electron cloud effects are expected to be severe; however, the simple structure of the lattice allows for easy variation of the circumference and bunch spacing, which may make it useful for future investigations.
Date: October 11, 2004
Creator: Wolski, Andrzej
Object Type: Report
System: The UNT Digital Library
Methods for Calibrating Basin-Wide Hydroacoustic Propagation in the Indian Ocean (open access)

Methods for Calibrating Basin-Wide Hydroacoustic Propagation in the Indian Ocean

This collaborative project was designed to test and compare methods for achieving full ocean basin propagation of hydroacoustic signals in the 5-100 Hz frequency band. Plans for a systematic calibration of the International Monitoring System (IMS) for nuclear testing were under consideration in 2000/2001. The results from this project provide information to guide such planning for future ocean basin calibration work. Several acoustic source types were tested during two sea-going experiments and most were successful at generating signals that propagated hundreds to thousands of km to be recorded at the Indian Ocean IMS hydrophone stations. Development and numerical modeling of imploding glass sphere sources was one component of this testing. The intent was to design a relatively simple-to-use source that is not subject to restrictions that can limit use of explosive charges, but whose signal is large enough to propagate 100-1000's km range. Analysis of IMS hydrophone data recording during the experiments was used to illustrate the extent of energy loss during signal propagation and to assess the accuracy with which the small acoustic sources could be located using methods typically employed for nuclear monitoring.
Date: October 11, 2004
Creator: Blackman, D; de Groot-Hedlin, C; Orcutt, J A; Harben, P H; Clarke, D B & Ramirez, A L
Object Type: Report
System: The UNT Digital Library
New Technology and Lunar Power Option for Power Beaming Propulsion (open access)

New Technology and Lunar Power Option for Power Beaming Propulsion

Orbit raising missions (LEO to GEO or beyond) are the only missions with enough current traffic to be seriously considered for near-term power beaming propulsion. Even these missions cannot justify the development expenditures required to deploy the required new laser, optical and propulsion technologies or the programmatic risks. To be deployed, the laser and optics technologies must be spin-offs of other funded programs. The manned lunar base nighttime power requirements may justify a major power beaming program with 2MW lasers and large optical systems. New laser and optical technologies may now make this mission plausible. If deployed these systems could be diverted for power beaming propulsion applications. Propulsion options include a thermal system with an Isp near 1000 sec., a new optical coupled thermal system with an Isp over 2000 sec. photovoltaic-ion propulsion systems with an Isp near 3000 sec., and a possible new optical coupled thermal system with an Isp over 2000 sec.
Date: October 11, 2004
Creator: Kare, J; Early, J; Krupke, W & Beach, R
Object Type: Article
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 88, No. 37, Ed. 1 Monday, October 11, 2004 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 88, No. 37, Ed. 1 Monday, October 11, 2004

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: October 11, 2004
Creator: Warren, Lee B.
Object Type: Newspaper
System: The Gateway to Oklahoma History

[Our Lady of Perpetual Help Church]

Photograph of the exterior of the Our Lady of Perpetual Help Catholic Church in Saspamco, Texas.
Date: October 11, 2004
Creator: unknown
Object Type: Photograph
System: The Portal to Texas History
PM Motor Parametric Design Analyses for a Hybrid Electric Vehicle Traction Drive Application (open access)

PM Motor Parametric Design Analyses for a Hybrid Electric Vehicle Traction Drive Application

The Department of Energy's (DOE) Office of FreedomCAR (Cooperative Automotive Research) and Vehicle Technologies office has a strong interest in making rapid progress in permanent magnet (PM) machine development. The DOE FreedomCAR program is directing various technology development projects that will advance the technology and hopefully lead to a near-term request for proposals (RFP) for a to-be-determined level of initial production. This aggressive approach is possible because the technology is clearly within reach and the approach is deemed essential, based on strong market demand, escalating fuel prices, and competitive considerations. In response, this study began parallel development paths that included a literature search/review, development and utilization of multiple parametric models, verification of the modeling methodology, development of an interior PM (IPM) machine baseline design, development of alternative machine baseline designs, and cost analyses for several candidate machines. This report summarizes the results of these activities as of September 2004. This report provides background and summary information for recent machine parametric studies and testing programs that demonstrate both the potential capabilities and technical limitations of brushless PM machines (axial gap and radial gap), the IPM machine, the surface-mount PM machines (interior or exterior rotor), induction machines, and switched-reluctance machines. The FreedomCAR …
Date: October 11, 2004
Creator: Staunton, R.H.
Object Type: Report
System: The UNT Digital Library
Protocols for Thermoluninescence and Optically Stimulated Luminescence Research at DOSAR (open access)

Protocols for Thermoluninescence and Optically Stimulated Luminescence Research at DOSAR

The Life Sciences Division (LSD) of Oak Ridge National Laboratory (ORNL) has a long record of radiation dosimetry research at the Dosimetry Applications Research (DOSAR) facility complex. These facilities have been used by a broad segment of the research community to perform a variety of experiments in areas including, but not limited to, radiobiology, radiation dosimeter and instrumentation development and calibration, and materials testing in a variety of radiation environments. Collaborations with the University of Tennessee-Knoxville (UTK) have also led to important contributions in the area of archaeometry, particularly as it relates to the use of radiation dosimetry to date archaeological artifacts. This manual is to serve as the primary instruction and operation manual for dosimetric and archaeometric research at DOSAR involving thermoluminescence (TL) and optically stimulated luminescence (OSL). Its purpose is to (1) provide protocols for common practices associated with the research, (2) outline the relevant organizational structure, (3) identify the Quality Assurance plan, and (4) describe all the procedures, operations, and responsibilities for safe and proper operation of associated equipment. Each person who performs research at DOSAR using TL/OSL equipment is required to read the latest revision of this manual and be familiar with its contents, and to …
Date: October 11, 2004
Creator: Bernal, S. M. & Bogard, J. S.
Object Type: Report
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 90, No. 24, Ed. 1 Monday, October 11, 2004 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 90, No. 24, Ed. 1 Monday, October 11, 2004

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: October 11, 2004
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Simulating thermal explosion of RDX-based explosives: Model comparison with experiment (open access)

Simulating thermal explosion of RDX-based explosives: Model comparison with experiment

We compare two-dimensional model results with measurements for the thermal, chemical and mechanical behavior in a thermal explosion experiment. Confined high explosives are heated at a rate of 1 C per hour until an explosion is observed. The heating, ignition, and deflagration phases are modeled using an Arbitrarily Lagrangian-Eulerian code (ALE3D) that can handle a wide range of time scales that vary from a structural to a dynamic hydro time scale. During the pre-ignition phase, quasi-static mechanics and diffusive thermal transfer from a heat source to the HE are coupled with the finite chemical reactions that include both endothermic and exothermic processes. Once the HE ignites, a hydro dynamic calculation is performed as a burn front propagates through the HE. Two RDX-based explosives, C-4 and PBXN-109, are considered, whose chemical-thermal-mechanical models are constructed based on measurements of thermal and mechanical properties along with small scale thermal explosion measurements. The simulated dynamic response of HE confinement during the explosive phase is compared to measurements in large scale thermal explosion tests. The explosion temperatures for both HE's are predicted to within 5 C. Calculated and measured wall strains provide an indication of vessel pressurization during the heating phase and violence during the …
Date: October 11, 2004
Creator: Yoh, J J; McClelland, M A; Maienschein, J L; Wardell, J F & Tarver, C M
Object Type: Article
System: The UNT Digital Library
Simulating Time-Dependent Energy Transfer Between Crossed Laser Beams in an Expanding Plasma (open access)

Simulating Time-Dependent Energy Transfer Between Crossed Laser Beams in an Expanding Plasma

A coupled mode system is derived to investigate a three-wave parametric instability leading to energy transfer between co-propagating laser beams crossing in a plasma flow. The model includes beams of finite width refracting in a prescribed transverse plasma flow with spatial and temporal gradients in velocity and density. The resulting paraxial light equations are discretized spatially with a Crank-Nicholson-type scheme, and these algebraic constraints are nonlinearly coupled with ordinary differential equations in time that describe the ion acoustic response. The entire nonlinear differential-algebraic system is solved using an adaptive, backward-differencing method coupled with Newton's method. A numerical study is conducted in two dimensions that compares the intensity gain of the fully time-dependent coupled mode system with the gain computed under the further assumption of a strongly-damped ion acoustic response. The results demonstrate a time-dependent gain suppression when the beam diameter is commensurate with the velocity gradient scale length. The gain suppression is shown to depend on time-dependent beam refraction and is interpreted as a time-dependent frequency shift.
Date: October 11, 2004
Creator: Hittinger, J. F.; Dorr, M. R.; Berger, R. L. & Williams, E. A.
Object Type: Article
System: The UNT Digital Library