Partner
UNT Libraries Government Documents Department
973
UNT Libraries Special Collections
216
Oklahoma Historical Society
121
National Museum of the Pacific War/Admiral Nimitz Foundation
35
Sterling Municipal Library
31
Carl Albert Congressional Research and Studies Center
20
Texas Historical Commission
14
UNT Libraries
14
Alvin Community College
13
Abilene Christian University Library
9
61 More
Collection
Office of Scientific & Technical Information Technical Reports
691
Texas Digital Newspaper Program
270
Congressional Research Service Reports
201
Oklahoma Digital Newspaper Program
145
Tocker Foundation Grant
128
LGBT Collections
94
Multicultural Center Records
48
National Museum of the Pacific War Oral History Collection
35
National Museum of the Pacific War Digital Archive
35
The Baytown Sun
31
116 More
Country
Year
Month
Language
1,693 Matching Results
Results open in a new window/tab.
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
[5th Annual Book Club Luncheon]
Video recording from The Black Academy of Arts and Letters recorded during their 5th Annual Book Club Luncheon event in 2004. This video features a discourse between prominent member of TBAAL and author Camika Spencer.
Date:
October 25, 2004
Creator:
unknown
Object Type:
Video
System:
The UNT Digital Library
Abortion: Legislative Response
The primary focus of this issue brief is legislative action with respect to abortion. However, discussion of those legislative proposals necessarily involves a brief discussion of the leading U.S. Supreme Court decisions concerning a woman’s right to choose whether to terminate her pregnancy. For a more detailed discussion of the relevant case law, see CRS Report 95-724, Abortion Law Development: A Brief Overview.
Date:
October 26, 2004
Creator:
Shimabukuro, Jon O.; Lewis, Karen J. & Ely, Dana
Object Type:
Report
System:
The UNT Digital Library
[ABSE booth at 2004 Homecoming]
A photograph of a booth during the 2004 Homecoming game tailgate. The poster is red and has school-themed curtains on the sides. It is for ABSE and lists the officers as "President: LaShandralyn Fry, Vice President: Monique Ervin, Secretary: Chisa Weaver, Founder: Laura Washington". People are visible past it underneath a large tent.
Date:
October 23, 2004
Creator:
University of North Texas. Multicultural Center.
Object Type:
Photograph
System:
The UNT Digital Library
Acceleration of Polarized Beams Using Multiple Strong Partial Siberian Snakes
Acceleration of polarized protons in the energy range of 5 to 25 GeV is particularly difficult since depolarizing spin resonances are strong enough to cause significant depolarization but full Siberian snakes cause intolerably large orbit excursions. Using a 20-30% partial Siberian snake both imperfection and intrinsic resonances can be overcome. Such a strong partial Siberian snake was designed for the Brookhaven AGS using a dual pitch helical superconducting dipole. Multiple strong partial snakes are also discussed for spin matching at beam injection and extraction.
Date:
October 10, 2004
Creator:
Roser, T.; Ahrens, L.; Bai, M.; Courant, E.; Glenn, J. W.; Gupta, R. C. et al.
Object Type:
Article
System:
The UNT Digital Library
Acceleressence: Dark energy from a phase transition at the seesawscale
Simple models are constructed for ''acceleressence'' dark energy: the latent heat of a phase transition occurring in a hidden sector governed by the seesaw mass scale v{sup 2}/M{sub Pl}, where v is the electroweak scale and M{sub Pl} the gravitational mass scale. In our models, the seesaw scale is stabilized by supersymmetry, implying that the LHC must discover superpartners with a spectrum that reflects a low scale of fundamental supersymmetry breaking. Newtonian gravity may be modified by effects arising from the exchange of fields in the acceleressence sector whose Compton wavelengths are typically of order the millimeter scale. There are two classes of models. In the first class the universe is presently in a metastable vacuum and will continue to inflate until tunneling processes eventually induce a first order transition. In the simplest such model, the range of the new force is bounded to be larger than 25 {micro}m in the absence of fine-tuning of parameters, and for couplings of order unity it is expected to be {approx} 100 {micro}m. In the second class of models thermal effects maintain the present vacuum energy of the universe, but on further cooling, the universe will ''soon'' smoothly relax to a matter dominated …
Date:
October 5, 2004
Creator:
Chacko, Z.; Hall, Lawrence J. & Nomura, Yasunori
Object Type:
Article
System:
The UNT Digital Library
Acoustic Detecting and Locating Gas Pipe Line Infringement Quarterly Report: Number 9
The extensive network of high-pressure natural gas transmission pipelines covering the United States provides an important infrastructure for our energy independence. Early detection of pipeline leaks and infringements by construction equipment, resulting in corrosion fractures, presents an important aspect of our national security policy. The National Energy Technology Laboratory Strategic Center for Natural Gas (SCVG) is and has been funding research on various applicable techniques. The WVU research team has focused on monitoring pipeline background acoustic signals generated and transmitted by gas flowing through the gas inside the pipeline. In case of a pipeline infringement, any mechanical impact on the pipe wall, or escape of high-pressure gas, generates acoustic signals traveling both up and down stream through the gas. Sudden changes in flow noise are detectable with a Portable Acoustic Monitoring Package (PAMP), developed under this contract. It incorporates a pressure compensating microphone and a signal- recording device. Direct access to the gas inside the line is obtained by mounting such a PAMP, with a 1/2 inch NPT connection, to a pipeline pressure port found near most shut-off valves. An FFT of the recorded signal subtracted by that of the background noise recorded one-second earlier appears to sufficiently isolate the …
Date:
October 31, 2004
Creator:
Loth, John L.; Morris, Gary J.; Palmer, George M.; Guiler, Richard & Browning, Patrick
Object Type:
Report
System:
The UNT Digital Library
Activation Energy for Grain Growth in Aluminum Coatings
To produce a specific grain size in metallic coatings requires precise control of the time at temperature during the deposition process. Aluminum coatings are deposited using electron-beam evaporation onto heated substrate surfaces. The grain size of the coating is determined upon examination of the microstructure in plan view and cross-section. Ideal grain growth is observed over the entire experimental range of temperature examined from 413 to 843 K. A transition in the activation energy for grain growth from 0.7 to 3.8 eV {center_dot} atom{sup -1} is observed as the temperature increases from <526 K to >588 K. The transition is indicative of the dominant mechanism for grain growth shifting with increasing temperature from grain boundary to lattice diffusion.
Date:
October 14, 2004
Creator:
Jankowski, Alan Frederic; Ferreira, J. L. & Hayes, Jeffrey P.
Object Type:
Article
System:
The UNT Digital Library
An adaptive radiation model for the origin of new genefunctions
The evolution of new gene functions is one of the keys to evolutionary innovation. Most novel functions result from gene duplication followed by divergence. However, the models hitherto proposed to account for this process are not fully satisfactory. The classic model of neofunctionalization holds that the two paralogous gene copies resulting from a duplication are functionally redundant, such that one of them can evolve under no functional constraints and occasionally acquire a new function. This model lacks a convincing mechanism for the new gene copies to increase in frequency in the population and survive the mutational load expected to accumulate under neutrality, before the acquisition of the rare beneficial mutations that would confer new functionality. The subfunctionalization model has been proposed as an alternative way to generate genes with altered functions. This model also assumes that new paralogous gene copies are functionally redundant and therefore neutral, but it predicts that relaxed selection will affect both gene copies such that some of the capabilities of the parent gene will disappear in one of the copies and be retained in the other. Thus, the functions originally present in a single gene will be partitioned between the two descendant copies. However, although this …
Date:
October 18, 2004
Creator:
Francino, M. Pilar
Object Type:
Article
System:
The UNT Digital Library
Adjusted Field Profile for the Chromaticity Cancellation in FFAG Accelerators.
In an earlier report they have reviewed four major rules to design the lattice of Fixed-Field Alternating-Gradient (FFAG) accelerators. One of these rules deals with the search of the Adjusted Field Profile, that is the field non-linear distribution along the length and the width of the accelerator magnets, to compensate for the chromatic behavior, and thus to reduce considerably the variation of betatron tunes during acceleration over a large momentum range. The present report defines the method for the search of the Adjusted Field Profile.
Date:
October 13, 2004
Creator:
Ruggiero, A. G.
Object Type:
Article
System:
The UNT Digital Library
Advanced Computational Model for Three-Phase Slurry Reactors Progress Report: October 2004
In this project, an Eulerian-Lagrangian formulation for analyzing three-phase slurry flows in a bubble column was developed. The approach used an Eulerian analysis of liquid flows in the bubble column, and made use of the Lagrangian trajectory analysis for the bubbles and particle motions. The bubble-bubble and particle-particle collisions are included the model. The model predictions are compared with the experimental data and good agreement was found An experimental setup for studying two-dimensional bubble columns was developed. The multiphase flow conditions in the bubble column were measured using optical image processing and Particle Image Velocimetry techniques (PIV). A simple shear flow device for bubble motion in a constant shear flow field was also developed. The flow conditions in simple shear flow device were studied using PIV method. Concentration and velocity of particles of different sizes near a wall in a duct flow was also measured. The technique of Phase-Doppler anemometry was used in these studies. An Eulerian volume of fluid (VOF) computational model for the flow condition in the two-dimensional bubble column was also developed. The liquid and bubble motions were analyzed and the results were compared with observed flow patterns in the experimental setup. Solid-fluid mixture flows in ducts …
Date:
October 1, 2004
Creator:
Ahmadi, Goodarz
Object Type:
Report
System:
The UNT Digital Library
Advanced Computing for 21st Century Accelerator Science and Technology
Dr. Dragt of the University of Maryland is one of the Institutional Principal Investigators for the SciDAC Accelerator Modeling Project Advanced Computing for 21st Century Accelerator Science and Technology whose principal investigators are Dr. Kwok Ko (Stanford Linear Accelerator Center) and Dr. Robert Ryne (Lawrence Berkeley National Laboratory). This report covers the activities of Dr. Dragt while at Berkeley during spring 2002 and at Maryland during fall 2003.
Date:
October 12, 2004
Creator:
Dragt, Alex J.
Object Type:
Report
System:
The UNT Digital Library
Advanced Core Design And Fuel Management For Pebble-Bed Reactors
A method for designing and optimizing recirculating pebble-bed reactor cores is presented. At the heart of the method is a new reactor physics computer code, PEBBED, which accurately and efficiently computes the neutronic and material properties of the asymptotic (equilibrium) fuel cycle. This core state is shown to be unique for a given core geometry, power level, discharge burnup, and fuel circulation policy. Fuel circulation in the pebble-bed can be described in terms of a few well?defined parameters and expressed as a recirculation matrix. The implementation of a few heat?transfer relations suitable for high-temperature gas-cooled reactors allows for the rapid estimation of thermal properties critical for safe operation. Thus, modeling and design optimization of a given pebble-bed core can be performed quickly and efficiently via the manipulation of a limited number key parameters. Automation of the optimization process is achieved by manipulation of these parameters using a genetic algorithm. The end result is an economical, passively safe, proliferation-resistant nuclear power plant.
Date:
October 1, 2004
Creator:
Gougar, Hans D.; Ougouag, Abderrafi M. & Terry, William K.
Object Type:
Report
System:
The UNT Digital Library
An Advanced Fracture Characterization and Well Path Navigation System for Effective Re-Development and Enhancement of Ultimate Recovery From the Complex Monterey Reservoir of South Ellwood Field, Offshore California
Venoco Inc, intends to re-develop the Monterey Formation, a Class III basin reservoir, at South Ellwood Field, Offshore Santa Barbara, California. Well productivity in this field varies significantly. Cumulative Monterey production for individual wells has ranged from 260 STB to 8,700,000 STB. Productivity is primarily affected by how well the well path connects with the local fracture system and the degree of aquifer support. Cumulative oil recovery to date is a small percentage of the original oil in place. To embark upon successful re-development and to optimize reservoir management, Venoco intends to investigate, map and characterize field fracture patterns and the reservoir conduit system. State of the art borehole imaging technologies including FMI, dipole sonic and cross-well seismic, interference tests and production logs will be employed to characterize fractures and micro faults. These data along with the existing database will be used for construction of a novel geologic model of the fracture network. Development of an innovative fracture network reservoir simulator is proposed to monitor and manage the aquifer's role in pressure maintenance and water production. The new fracture simulation model will be used for both planning optimal paths for new wells and improving ultimate recovery. In the second phase …
Date:
October 29, 2004
Creator:
Horner, Steve
Object Type:
Report
System:
The UNT Digital Library
The Advanced High-Temperature Reactor (AHTR) for Producing Hydrogen to Manufacture Liquid Fuels
Conventional world oil production is expected to peak within a decade. Shortfalls in production of liquid fuels (gasoline, diesel, and jet fuel) from conventional oil sources are expected to be offset by increased production of fuels from heavy oils and tar sands that are primarily located in the Western Hemisphere (Canada, Venezuela, the United States, and Mexico). Simultaneously, there is a renewed interest in liquid fuels from biomass, such as alcohol; but, biomass production requires fertilizer. Massive quantities of hydrogen (H2) are required (1) to convert heavy oils and tar sands to liquid fuels and (2) to produce fertilizer for production of biomass that can be converted to liquid fuels. If these liquid fuels are to be used while simultaneously minimizing greenhouse emissions, nonfossil methods for the production of H2 are required. Nuclear energy can be used to produce H2. The most efficient methods to produce H2 from nuclear energy involve thermochemical cycles in which high-temperature heat (700 to 850 C) and water are converted to H2 and oxygen. The peak nuclear reactor fuel and coolant temperatures must be significantly higher than the chemical process temperatures to transport heat from the reactor core to an intermediate heat transfer loop and …
Date:
October 6, 2004
Creator:
Forsberg, C. W.; Peterson, P. F. & Ott, L.
Object Type:
Article
System:
The UNT Digital Library
Advanced Hot Section Materials and Coatings Test Rig
The Hyperbaric Advanced Hot Section Materials & Coating Test Rig program provides design and implementation of a laboratory rig capable of simulating the hot gas path conditions of coal-gas fired industrial gas turbine engines. The principal activities during this reporting period were the continuation of test section detail design and developing specifications for auxiliary systems and facilities.
Date:
October 30, 2004
Creator:
Davies, Dan
Object Type:
Report
System:
The UNT Digital Library
Advanced Hydrogen Transport Membranes for Vision 21 Fossil Fuel Plants
During this quarter, work was focused on characterizing the stability of layered composite membranes in a one hundred percent permeate environment. Permeation data was also collected on cermets as a function of thickness. A thin film deposition procedure was used to deposit dense thin BCY/Ni onto a tubular porous support. Thin film tubes were then tested for permeation at ambient pressure. Process flow diagrams were prepared for inclusion of hydrogen separation membranes into IGCC power plants under varying conditions. Finally, membrane promoted alkane dehydrogenation experiments were performed.
Date:
October 21, 2004
Creator:
Evenson, Carl R.; Sammells, Anthony F.; Treglio, Richard T.; Balachandran, U.; Kleiner, Richard N.; Stephan, James E. et al.
Object Type:
Report
System:
The UNT Digital Library
Advanced Nuclear Research Reactor
This report describes technical modifications implemented by INVAP to improve the safety of the Research Reactors the company designs and builds.
Date:
October 6, 2004
Creator:
Lolich, J.V.
Object Type:
Article
System:
The UNT Digital Library
Advanced ST Plasma Scenario Simulations for NSTX
Integrated scenario simulations are done for NSTX [National Spherical Torus Experiment] that address four primary milestones for developing advanced ST configurations: high {beta} and high {beta}{sub N} inductive discharges to study all aspects of ST physics in the high-beta regime; non-inductively sustained discharges for flattop times greater than the skin time to study the various current-drive techniques; non-inductively sustained discharges at high {beta} for flattop times much greater than a skin time which provides the integrated advanced ST target for NSTX; and non-solenoidal start-up and plasma current ramp-up. The simulations done here use the Tokamak Simulation Code (TSC) and are based on a discharge 109070. TRANSP analysis of the discharge provided the thermal diffusivities for electrons and ions, the neutral-beam (NB) deposition profile, and other characteristics. CURRAY is used to calculate the High Harmonic Fast Wave (HHFW) heating depositions and current drive. GENRAY/CQL3D is used to establish the heating and CD [current drive] deposition profiles for electron Bernstein waves (EBW). Analysis of the ideal-MHD stability is done with JSOLVER, BALMSC, and PEST2. The simulations indicate that the integrated advanced ST plasma is reachable, obtaining stable plasmas with {beta} {approx} 40% at {beta}{sub N}'s of 7.7-9, I{sub P} = 1.0 MA, …
Date:
October 28, 2004
Creator:
Kessel, C.E.; Synakowski, E.J.; Gates, D.A.; Harvey, R.W.; Kaye, S.M.; Mau, T.K. et al.
Object Type:
Report
System:
The UNT Digital Library
Advanced Testing Techniques to Measure the PWSCC Resistance of Alloy 690 and its Weld Metals
Wrought Alloy 600 and its weld metals (Alloy 182 and Alloy 82) were originally used in pressurized water reactors (PWRs) due to the material's inherent resistance to general corrosion in a number of aggressive environments and because of a coefficient of thermal expansion that is very close to that of low alloy and carbon steel. Over the last thirty years, stress corrosion cracking in PWR primary water (PWSCC) has been observed in numerous Alloy 600 component items and associated welds, sometimes after relatively long incubation times. The occurrence of PWSCC has been responsible for significant downtime and replacement power costs. As part of an ongoing, comprehensive program involving utilities, reactor vendors and engineering/research organizations, this report will help to ensure that corrosion degradation of nickel-base alloys does not limit service life and that full benefit can be obtained from improved designs for both replacement components and new reactors.
Date:
October 1, 2004
Creator:
P.Andreson
Object Type:
Report
System:
The UNT Digital Library
Advances in Comprehensive Gyrokinetic Simulations of Transport in Tokamaks
A continuum global gyrokinetic code GYRO has been developed to comprehensively simulate core turbulent transport in actual experimental profiles and enable direct quantitative comparisons to the experimental transport flows. GYRO not only treats the now standard ion temperature gradient (ITG) mode turbulence, but also treats trapped and passing electrons with collisions and finite {beta}, equilibrium ExB shear stabilization, and all in real tokamak geometry. Most importantly the code operates at finite relative gyroradius ({rho}{sub *}) so as to treat the profile shear stabilization and nonlocal effects which can break gyroBohm scaling. The code operates in either a cyclic flux-tube limit (which allows only gyroBohm scaling) or globally with physical profile variation. Bohm scaling of DIII-D L-mode has been simulated with power flows matching experiment within error bars on the ion temperature gradient. Mechanisms for broken gyroBohm scaling, neoclassical ion flows embedded in turbulence, turbulent dynamos and profile corrugations, are illustrated.
Date:
October 1, 2004
Creator:
Waltz, R. E.; Candy, J.; Hinton, F. L.; Estrada-Mila, C. & Kinsey, J. E.
Object Type:
Article
System:
The UNT Digital Library
Advances in Comprehensive Gyrokinetic Simulations of Transport in Tokamaks
A continuum global gyrokinetic code GYRO has been developed to comprehensively simulate core turbulent transport in actual experimental profiles and enable direct quantitative comparisons to the experimental transport flows. GYRO not only treats the now standard ion temperature gradient (ITG) mode turbulence, but also treats trapped and passing electrons with collisions and finite {beta}, equilibrium ExB shear stabilization, and all in real tokamak geometry. Most importantly the code operates at finite relative gyroradius ({rho}{sub *}) so as to treat the profile shear stabilization and nonlocal effects which can break gyroBohm scaling. The code operates in either a cyclic flux-tube limit (which allows only gyroBohm scaling) or a globally with physical profile variation. Rohm scaling of DIII-D L-mode has been simulated with power flows matching experiment within error bars on the ion temperature gradient. Mechanisms for broken gyroBohm scaling, neoclassical ion flows embedded in turbulence, turbulent dynamos and profile corrugations, plasma pinches and impurity flow, and simulations at fixed flow rather than fixed gradient are illustrated and discussed.
Date:
October 1, 2004
Creator:
Waltz, R. E.; Candy, J.; Hinton, F. L.; Estrada-Mila, C. & Kinsey, J. E.
Object Type:
Article
System:
The UNT Digital Library
Advancing the Ion Beam Thin Film Planarization Process for the Smoothing of Substrate Particles
This report addresses the advancement of the ion beam thin film planarization process for the smoothing of substrate particles.
Date:
October 27, 2004
Creator:
Mirkarimi, P.; Spiller, E.; Baker, S.; Robinson, J.; Stearns, D.; Liddle, J. A. et al.
Object Type:
Article
System:
The UNT Digital Library
ADVANCING THE ION BEAM THIN FILM PLANARIZATION PROCESS FOR THE SMOOTHING OF SUBSTRATE PARTICLES
For a number of technologies small substrate contaminants are undesirable, and for one technology in particular, extreme ultraviolet lithography (EUVL), they can be a very serious issue. We have demonstrated that the Ion Beam Thin Film Planarization Process, a coating process designed to planarize substrate asperities, can be extended to smooth {approx}70 nm and {approx}80 nm diameter particles on EUVL reticle substrates to a height of {approx}0.5 nm, which will render them noncritical in an EUVL printing process. We demonstrate this smoothing process using controlled nanoscale substrate particles and lines fabricated with an e-beam lithography process. The above smoothing process was also modified to yield an excellent reflectance/wavelength uniformity and a good EUV reflectivity for the multilayer, which is required for EUVL reticles. Cross-sectional TEM on a smoothed substrate line defect shows excellent agreement with results obtained from our multilayer growth model.
Date:
October 19, 2004
Creator:
Mirkarimi, P B; Spiller, E; Baker, S L; Robinson, J C; Stearns, D G; Liddle, J A et al.
Object Type:
Article
System:
The UNT Digital Library