Partner
UNT Libraries Government Documents Department
26,810
UNT Libraries Special Collections
1,759
Oklahoma Historical Society
937
Texas Historical Commission
606
UNT Libraries
379
UNT College of Information
308
National Museum of the Pacific War/Admiral Nimitz Foundation
171
Sterling Municipal Library
116
Oklahoma State Firefighters Museum
100
UNT Music Library
57
99 More
Collection
Office of Scientific & Technical Information Technical Reports
24,856
Texas Digital Newspaper Program
1,320
The Black Academy of Arts and Letters Records
1,131
Congressional Research Service Reports
769
Oklahoma Digital Newspaper Program
698
THC National Register Collection
597
Defense Base Closure and Realignment Commission
579
Tocker Foundation Grant
538
Government Accountability Office Reports
442
Jim Argo Collection
410
178 More
Degree Department
Degree Discipline
Degree Level
Country
States
Decade
Year
Month
Day
Collimation of dense plasma jets created by low energy laser pulses
None
Date:
December 1, 2009
Creator:
Purvis, M. A.; Grava, J.; Filevich, J.; Ryan, D. P.; Moon, S. J.; Dunn, J. et al.
Object Type:
Article
System:
The UNT Digital Library
Colorado's Prospects for Interstate Commerce in Renewable Power
Colorado has more renewable energy potential than it is ever likely to need for its own in-state electricity consumption. Such abundance may suggest an opportunity for the state to sell renewable power elsewhere, but Colorado faces considerable competition from other western states that may have better resources and easier access to key markets on the West Coast. This report examines factors that will be important to the development of interstate commerce for electricity generated from renewable resources. It examines market fundamentals in a regional context, and then looks at the implications for Colorado.
Date:
December 1, 2009
Creator:
Hurlbut, D. J.
Object Type:
Report
System:
The UNT Digital Library
Compact, energy EFFICIENT neutron source: enabling technology for various applications
A novel neutron source comprising of a deuterium beam (energy of about 100 KeV) injected into a tube filled with tritium gas and/or tritium plasma that generates D-T fusion reactions, whose products are 14.06 MeV neutrons and 3.52 MeV alpha particles, is described. At the opposite end of the tube, the energy of deuterium ions that did not interact is recovered. Beryllium walls of proper thickness can be utilized to absorb 14 MeV neutrons and release 2-3 low energy neutrons. Each ion source and tube forms a module. Larger systems can be formed from multiple units. Unlike currently proposed methods, where accelerator-based neutron sources are very expensive, large, and require large amounts of power for operation, this neutron source is compact, inexpensive, easy to test and to scale up. Among possible applications for this neutron source concept are sub-critical nuclear breeder reactors and transmutation of radioactive waste.
Date:
December 1, 2009
Creator:
Hershcovitch, A. & Roser, T.
Object Type:
Report
System:
The UNT Digital Library
Comparison of IUPAC k0 Values and Neutron Cross Sections to Determine a Self-consistent Set of Data for Neutron Activation Analysis
Independent databases of nuclear constants for Neutron Activation Analysis (NAA) have been independently maintained by the physics and chemistry communities for many year. They contain thermal neturon cross sections s0, standardization values k0, and transition probabilities Pg. Chemistry databases tend to rely upon direct measurements of the nuclear constants k0 and Pg which are often published in chemistry journals while the physics databases typically include evaluated s0 and Pg data from a variety of experiments published mainly in physics journals. The IAEA/LBNL Evaluated Gamma-ray Activation File (EGAF) also contains prompt and delayed g-ray cross sections sg from Prompt Gamma-ray Activation Analysis (PGAA) measurements that can also be used to determine k0 and s0 values. As a result several independent databases of fundamental constants for NAA have evolved containing slightly different and sometimes discrepant results. An IAEA CRP for a Reference Database for Neutron Activation Analysis was established to compare these databases and investigate the possibilitiy of producing a self-consistent set of s0, k0, sg, and Pg values for NAA and other applications. Preliminary results of this IAEA CRP comparison are given in this paper.
Date:
December 1, 2009
Creator:
Firestone, Richard B & Revay, Zsolt
Object Type:
Article
System:
The UNT Digital Library
Comparison of the NDA of HEU Oxide between the AWCC and the HPGe Detector
This paper compares the performance of the Active Well Coincidence Counter (AWCC) with the performance of high resolution gamma spectrometry using an HPGe detector to nondestructively assay highly enriched (HEU) oxide. Traditionally the AWCC was considered to be the more appropriate instrument for this measurement. Although the AWCC had a high degree of precision, the HPGe provided the more accurate measurement of this material. The AWCC determines mass of U-235 from the coincident pairs of neutron detections, or doubles rate. The HPGe determines the mass of both U-235 and U238, the enrichment, and the quantity of other radioisotopes. The Tl-208 gamma rays were used to verify the amount of attenuation for the HPGe analysis. Fifty-four cans of enriched U3O8 were shipped to the Y-12 National Security Complex from Los Alamos National Laboratory (LANL) under Scrap Declaration LANL-45. The declared values for net weight, mass of uranium, mass of U-235, and enrichment (percent mass of U-235 to total uranium) are shown in Table A-1. The masses of U-235 range from 104g to 2404g and the enrichment varies from 20% to 98%.
Date:
December 1, 2009
Creator:
Chiang, L. G.; Oberer, R. B.; Gunn, C. A.; Dukes, E. E. & Akin, J. A.
Object Type:
Report
System:
The UNT Digital Library
Connecting the molecular scale to the continuum scale for diffusion processes in smectite-rich porous media
In this paper, we address the manner in which the continuum-scale diffusive properties of smectite-rich porous media arise from their molecular- and pore-scale features. Our starting point is a successful model of the continuum-scale apparent diffusion coefficient for water tracers and cations which decomposes it as a sum of pore-scale terms describing diffusion in macropore and interlayer 'compartments.' We then apply molecular dynamics (MD) simulations to determine molecular-scale diffusion coefficients D{sub interlayer} of water tracers and representative cations (Na{sup +}, Cs{sup +}, Sr{sup 2+}) in Na-smectite interlayers. We find that a remarkably simple expression relates D{sub interlayer} to the pore-scale parameter {delta}{sub nanopore} {<=} 1, a constrictivity factor that accounts for the lower mobility in interlayers as compared to macropores: {delta}{sub nanopore} = D{sub interlayer}/D{sub 0}, where D{sub 0} is the diffusion coefficient in bulk liquid water. Using this scaling expression, we can accurately predict the apparent diffusion coefficients of tracer H{sub 2}O, Na{sup +}, Sr{sup 2+} and Cs{sup +}+ in compacted Na-smectite-rich materials.
Date:
December 1, 2009
Creator:
Bourg, I.C. & Sposito, G.
Object Type:
Article
System:
The UNT Digital Library
Corrective Action Investigation Plan for Corrective Action Unit 367: Area 10 Sedan, Ess and Uncle Unit Craters Nevada Test Site, Nevada, Revision 0
Corrective Action Unit 367 is located in Area 10 of the Nevada Test Site, which is approximately 65 miles northwest of Las Vegas, Nevada. Corrective Action Unit 367 comprises the four corrective action sites (CASs) listed below: • 10-45-01, U-10h Crater (Sedan) • 10-45-02, Ess Crater Site • 10-09-03, Mud Pit • 10-45-03, Uncle Crater Site The CASs in CAU 367 are being investigated because hazardous and/or radioactive contaminants may be present in concentrations that exceed risk-based corrective action (RBCA) levels. Existing information on the nature and extent of potential contamination is insufficient to evaluate and recommend CAAs for the CASs. Additional information will be generated by conducting a CAI before evaluating and selecting CAAs. The scope of the corrective action investigation for CAU 367 includes the following activities: • Move surface debris and/or materials, as needed, to facilitate sampling. • Conduct radiological surveys. • Collect and submit environmental samples for laboratory analysis to determine the area where TED at the site exceeds FALs (i.e., corrective action boundary). • Evaluate TED to potential receptors in areas along Mercury Highway that have been impacted by a release of radionuclides from the Sedan test. • Collect and submit environmental samples for laboratory …
Date:
December 1, 2009
Creator:
Matthews, Patrick
Object Type:
Report
System:
The UNT Digital Library
Cost Methodology for Biomass Feedstocks: Herbaceous Crops and Agricultural Residues
This report describes a set of procedures and assumptions used to estimate production and logistics costs of bioenergy feedstocks from herbaceous crops and agricultural residues. The engineering-economic analysis discussed here is based on methodologies developed by the American Society of Agricultural and Biological Engineers (ASABE) and the American Agricultural Economics Association (AAEA). An engineering-economic analysis approach was chosen due to lack of historical cost data for bioenergy feedstocks. Instead, costs are calculated using assumptions for equipment performance, input prices, and yield data derived from equipment manufacturers, research literature, and/or standards. Cost estimates account for fixed and variable costs. Several examples of this costing methodology used to estimate feedstock logistics costs are included at the end of this report.
Date:
December 1, 2009
Creator:
Turhollow, Anthony F., Jr.; Webb, Erin & Sokhansanj, Shahabaddine
Object Type:
Report
System:
The UNT Digital Library
CROSS SECTION MEASUREMENTS IN THE MAIN INJECTOR PARTICLE PRODUCTION (FNAL-E907) EXPERIMENT AT 58 GEV ENERGY
Cross-sections are presented for 58 GeV {pi}, K, and p on a wide range of nuclear targets. These cross-sections are essential for determining the neutrino flux in measurements of neutrino cross-sections and oscillations. The E907 Main Injector Particle Production (MIPP) experiment at Fermilab is a fixed target experiment for measuring hadronic particle production using primary 120 GeV/c protons and secondary {pi}, K, and p beams. The particle identification is made by dE/dx in a time projection chamber, and by time-of-flight, differential Cherenkov and ring imaging Cherenkov detectors, which together cover a wide range of momentum from 0.1 GeV/c up to 120 GeV/c. MIPP targets span the periodic table, from hydrogen to uranium, including beryllium and carbon. The MIPP has collected {approx} 0.26 x 10{sup 6} events of 58 GeV/c secondary particles produced by protons from the main injector striking a carbon target.
Date:
December 1, 2009
Creator:
Gunaydin, Yusuf Oguzhan
Object Type:
Thesis or Dissertation
System:
The UNT Digital Library
Data Diodes in Support of a Power Grid Trustworthy Cyber Infrastructure
Industrial Control Systems (ICS) are an integral part of the industrial infrastructure providing for the national good. While sharing basic constructs with Information Technology (IT) business systems, ICSs are technically, administratively, and functionally more complex and unique than business IT systems. Critical infrastructure protection focuses on protecting and maintaining a safe and reliable supply of electric power, oil, water, gasoline, chemicals, food, etc. Cyber vul-nerabilities are important if they can affect the safe, functional performance of these systems and processes. The majority of ICS exhibit vulnerable devices with unsecured physical access and/or subject to insider attack. In this whitepaper, we advocate trusted process control networks as a way to address the serious cyber security flaws which combines both white/black listing into a design philosophy that addresses information warfare scenarios, software process monitoring and an attack recognition and management architecture.
Date:
December 1, 2009
Creator:
Sheldon, Frederick T; MacIntyre, Lawrence Paul; Okhravi, Hamed & Munson, Dr. John C.
Object Type:
Report
System:
The UNT Digital Library
Decoupling Policies: Options to Encourage Energy Efficiency Policies for Utilities; Clean Energy Policies in States and Communities, National Renewable Energy Laboratory (NREL) (Brochure)
This document discusses the policy of decoupling in utilities and how it can be used to encourage energy efficiency.
Date:
December 1, 2009
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Demographic Study of Texas Lottery Players: 2009
This report presents the results of a random survey of adult Texas residents aged 18 and older, conducted by the University of Houston Center for Public Policy to measure the citizen participation rates, the distribution and frequency of play, and the demographic profiles of past-year lottery players and non-players.
Date:
December 1, 2009
Creator:
University of Houston. Center for Public Policy.
Object Type:
Report
System:
The Portal to Texas History
Department of Homeland Security Assistance to States and Localities: A Summary and Issues for the 111th Congress
This report summarizes several emergency management and homeland security programs, and identifies and analyzes potential issues for the 111th Congress. These issues include the purpose and number of assistance programs; the evaluation of the use of grant funding; the determination of eligible grant recipients; the programs' funding amounts; and the programs; funding distribution methodologies.
Date:
December 1, 2009
Creator:
Reese, Shawn
Object Type:
Report
System:
The UNT Digital Library
Development of Eastern Regional Wind Resource and Wind Plant Output Datasets: March 3, 2008 -- March 31, 2010
The objective of this project was to provide wind resource inputs to the Eastern Wind Integration and Transmission Study.
Date:
December 1, 2009
Creator:
Brower, M.
Object Type:
Report
System:
The UNT Digital Library
Development Status of the PEBBLES Code for Pebble Mechanics: Improved Physical Models and Speed-up
PEBBLES is a code for simulating the motion of all the pebbles in a pebble bed reactor. Since pebble bed reactors are packed randomly and not precisely placed, the location of the fuel elements in the reactor is not deterministically known. Instead, when determining operating parameters the motion of the pebbles can be simulated and stochastic locations can be found. The PEBBLES code can output information relevant for other simulations of the pebble bed reactors such as the positions of the pebbles in the reactor, packing fraction change in an earthquake, and velocity profiles created by recirculation. The goal for this level three milestone was to speedup the PEBBLES code through implementation on massively parallel computer. Work on this goal has resulted in speeding up both the single processor version and creation of a new parallel version of PEBBLES. Both the single processor version and the parallel running capability of the PEBBLES code have improved since the fiscal year start. The hybrid MPI/OpenMP PEBBLES version was created this year to run on the increasingly common cluster hardware profile that combines nodes with multiple processors that share memory and a cluster of nodes that are networked together. The OpenMP portions use …
Date:
December 1, 2009
Creator:
Cogliati, Joshua J. & Ougouag, Abderrafi M.
Object Type:
Report
System:
The UNT Digital Library
Direct search for dark matter
Dark matter is hypothetical matter which does not interact with electromagnetic radiation. The existence of dark matter is only inferred from gravitational effects of astrophysical observations to explain the missing mass component of the Universe. Weakly Interacting Massive Particles are currently the most popular candidate to explain the missing mass component. I review the current status of experimental searches of dark matter through direct detection using terrestrial detectors.
Date:
December 1, 2009
Creator:
Yoo, Jonghee
Object Type:
Article
System:
The UNT Digital Library
Disdrometer and Tipping Bucket Rain Gauge Handbook
The Distromet disdrometer model RD-80 and NovaLynx tipping bucket rain gauge model 260-2500E-12 are two devices deployed a few meters apart to measure the character and amount of liquid precipitation. The main purpose of the disdrometer is to measure drop size distribution, which it does over 20 size classes from 0.3 mm to 5.4 mm. The data from both instruments can be used to determine rain rate. The disdrometer results can also be used to infer several properties including drop number density, radar reflectivity, liquid water content, and energy flux. Two coefficients, N0 and Λ, from an exponential fit between drop diameter and drop number density, are routinely calculated. Data are collected once a minute. The instruments make completely different kinds of measurements. Rain that falls on the disdrometer sensor moves a plunger on a vertical axis. The disdrometer transforms the plunger motion into electrical impulses whose strength is proportional to drop diameter. The rain gauge is the conventional tipping bucket type. Each tip collects an amount equivalent to 0.01 in. of water, and each tip is counted by a data acquisition system anchored by a Campbell CR1000 data logger.
Date:
December 1, 2009
Creator:
MJ, Bartholomew.
Object Type:
Report
System:
The UNT Digital Library
Doctoral Recital: 2009-12-01 - Daewook Kim, trumpet
Recital presented at the UNT College of Music Recital Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date:
December 1, 2009
Creator:
Kim, Daewook
Object Type:
Sound
System:
The UNT Digital Library
Doctoral Recital: 2009-12-01 - Damin Spritzer, organ
Recital presented at the UNT College of Music Main Auditorium in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date:
December 1, 2009
Creator:
Spritzer, Damin
Object Type:
Sound
System:
The UNT Digital Library
Doctoral Recital: 2009-12-01 - Etienne Stoupy, trumpet
Recital presented at the UNT College of Music Recital Hall in partial fulfillment of the Doctor of Musical Arts (DMA) degree.
Date:
December 1, 2009
Creator:
Stoupy, Etienne
Object Type:
Sound
System:
The UNT Digital Library
Double parton interactions in photon+3 jet events in ppbar collisions sqrt{s}=1.96 TeV
We have used a sample of photon+3 jets events collected by the D0 experiment with an integrated luminosity of about 1 fb{sup -1} to determine the fraction of events with double parton scattering (f{sub DP}) in a single ppbar collision at {radical}s = 1.96 TeV. The DP fraction and effective cross section (sigma{sub eff}), a process-independent scale parameter related to the parton density inside the nucleon, are measured in three intervals of the second (ordered in p{sub T}) jet transverse momentum pT{sub jet2} within the range 15 < pT{sub jet2} < 30 GeV. In this range, f{sub DP} varies between 0.23 < f{sub DP} < 0.47, while sigma{sub eff} has the average value sigma{sub effave} = 16.4 {+-} 0.3(stat) {+-} 2.3(syst) mb.
Date:
December 1, 2009
Creator:
Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Object Type:
Article
System:
The UNT Digital Library
The Ds and D+ Leptonic Decay Constants from Lattice QCD
We present the leptonic decay constants f{sub D{sub s}} and f{sub D{sup +}} computed on the MILC collaboration's 2+1 flavor asqtad gauge ensembles. We use clover heavy quarks with the Fermilab interpretation and improved staggered light quarks. The simultaneous chiral and continuum extrapolation, which determines both decay constants, includes partially-quenched lattice results at lattice spacings a {approx} 0.09, 0.12 and 0.15 fm. We have made several recent improvements in our analysis: (a) we include terms in the fit describing leading order heavy-quark discretization effects, (b) we have adopted a more precise input r{sub 1} value consistent with our other D and B meson studies, (c) we have retuned the input bare charm masses based upon the new r{sub 1}. Our preliminary results are f{sub D{sub s}} = 260 {+-} 10 MeV and f{sub D{sup +}} = 217 {+-} 10 MeV.
Date:
December 1, 2009
Creator:
Bazavov, A.; Bernard, C.; DeTar, C.; Freeland, E. D.; Gamiz, E.; Gottlieb, Steven et al.
Object Type:
Article
System:
The UNT Digital Library
E85 Dispenser Study
This study reviews E85 dispensing infrastructure advances and issues and evaluates the geographic concentration of flexible fuel vehicles (FFVs), E85 stations, ethanol production facilities, and E85 suppliers. Costs, space, financial incentives, and barriers to adding E85 fueling equipment at existing stations are also assessed. This study found that E85 is increasingly available in the U.S. in half of the states; however, the other half have minimal or no E85 fueling options. Despite these gains, E85 is only available at 1% of U.S. gasoline stations. Ethanol production reached 9.5 billion gallons in 2008, but less than 1% is consumed as E85. FFVs have not reached a significant concentration in any county, metropolitan area, or state.
Date:
December 1, 2009
Creator:
Moriarty, K.; Johnson, C.; Sears, T. & Bergeron, P.
Object Type:
Report
System:
The UNT Digital Library
An Economic Analysis of the Homebuyer Tax Credit
This report provides an economic analysis of the homebuyer tax credit. Data suggest that home prices in general may be stabilizing and that the home inventory is beginning to return to a more normal level. Given the close proximity of these improvements to when the homebuyer tax credit was enacted by the Housing and Economic Recovery Act of 2008 and first modified by the American Recovery and Reinvestment Act of 2009, one could argue that the tax credit was the cause of these improvements.
Date:
December 1, 2009
Creator:
Keightley, Mark P.
Object Type:
Report
System:
The UNT Digital Library