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METHODOLOGY, ASSUMPTIONS, AND BASELINE DATA FOR THE REPOSITORY DESIGN AND OPERATION, RAIL CORRIDORS, AND HEAVY TRUCK ROUTES, CLARK COUNTY, NEVADA, LINCOLN COUNTY, NEVADA, NYE COUNTY, NEVADA, "REST OF NEVADA", STATE OF NEVADA
None
Date:
January 25, 2002
Creator:
/a, n
Object Type:
Report
System:
The UNT Digital Library
Side-surface passivation effect on the electrical properties of metal-CdZnTe-metal structures
N/A
Date:
August 25, 2013
Creator:
A., Bolotnikov; Sklyarchuk, V.; Fochuk, P.; Zakharuk, Z.; Grill, R.; Kutny, V. Rybka, A. et al.
Object Type:
Article
System:
The UNT Digital Library
Project Hanford management contract quality improvement project management plan
On July 13, 1998, the U.S. Department of Energy, Richland Operations Office (DOE-RL) Manager transmitted a letter to Fluor Daniel Hanford, Inc. (FDH) describing several DOE-RL identified failed opportunities for FDH to improve the Quality Assurance (QA) Program and its implementation. In addition, DOE-RL identified specific Quality Program performance deficiencies. FDH was requested to establish a periodic reporting mechanism for the corrective action program. In a July 17, 1998 response to DOE-RL, FDH agreed with the DOE concerns and committed to perform a comprehensive review of the Project Hanford Management Contract (PHMC) QA Program during July and August, 1998. As a result, the Project Hanford Management Contract Quality Improvement Plan (QIP) (FDH-3508) was issued on October 21, 1998. The plan identified corrective actions based upon the results of an in-depth Quality Program Assessment. Immediately following the scheduled October 22, 1998, DOE Office of Enforcement and Investigation (EH-10) Enforcement Conference, FDH initiated efforts to effectively implement the QIP corrective actions. A Quality Improvement Project (QI Project) leadership team was assembled to prepare a Project Management Plan for this project. The management plan was specifically designed to engage a core team and the support of representatives from FDH and the major subcontractors …
Date:
March 25, 1999
Creator:
ADAMS, D.E.
Object Type:
Report
System:
The UNT Digital Library
"CONFIRMATORY SURVEY RESULTS FOR THE ABB COMBUSTION ENGINEERING SITE WINDSOR, CONNECTICUT DCN 5158-SR-02-2
The objectives of the confirmatory activities were to provide independent contractor field data reviews and to generate independent radiological data for use by the NRC in evaluating the adequacy and accuracy of the contractor�s procedures and FSS results. ORAU reviewed ABB CE�s decommissioning plan, final status survey plan, and the applicable soil DCGLs, which were developed based on an NRC-approved radiation dose assessment. The surveys include gamma surface scans, gamma direct measurements, and soil sampling.
Date:
March 25, 2013
Creator:
ADAMS, WADE C
Object Type:
Report
System:
The UNT Digital Library
Charged Higgs bosons in the transition region M{sub H{sup {+-}}} {approx} m{sub t} at the LHC
We illustrate preliminary results obtained through Monte Carlo (HERWIG) and detector (ATLFAST) simulations of the H{sup {+-}} {yields} {tau}{sup {+-}}{nu}{sub {tau}} signature of charged Higgs bosons with masses comparable to that of the top quark.
Date:
May 25, 2003
Creator:
ASSAMAGAN,K. A. GUCHAIT,M. MORETTI,S.
Object Type:
Article
System:
The UNT Digital Library
Hydrogen Storage Properties of the Tetrahydrofuran Treated Magnesium
The electronic structure, crystalline feature and morphology of the tetrahydrofuran (THF) treated magnesium, along with its hydriding and dehydriding properties have been investigated. The THF treated magnesium absorbs 6.3 wt per cent hydrogen at 723K and 3.5 MPa. After hydrogenation, in addition to the expected MgH2, a new less-stable hydride phase appears at 673K, but not at a lower temperature. Desorption produces 5.5 wt per cent hydrogen at 723K against a back pressure of 1.3 Pa after 20 cycles of hydriding-dehydriding. The THF treatment improves the kinetics of hydrogen absorption and desorption significantly. From 723K to 623K, the THF treated Mg demonstrates acceptable reaction rates. XPS studies show that tetrahydrofuran treatment causes the electronic energy state of the magnesium surface atoms to change, but the XRD studies show the crystal structure remains unchanged. Metallographic observation of the bulk hydrides of THF treated magnesium reveal they are poly-crystalline wi th the wide-spreading slip bands and twins within the crystals, indicating the phase transformation upon hydriding causes serious stress and distortion. It appears this microstructural deformation explains the much higher energy requirements (higher pressure and temperature) for magnesium hydrogenation than the simple lattice expansion that accompany hydrogen uptake for LaNi5 and FeTi.
Date:
May 25, 2004
Creator:
AU, MING
Object Type:
Article
System:
The UNT Digital Library
Phenomenology of the deuteron electromagnetic form factors
A rigorous extraction of the deuteron charge form factors from tensor polarization data in elastic electron-deuteron scattering, at given values of the 4-momentum transfer, is presented. Then the world data for elastic electron-deuteron scattering is used to parameterize, in three different ways, the three electromagnetic form factors of the deuteron in the 4-momentum transfer range 0-7 fm. This procedure is made possible with the advent of recent polarization measurements. The parameterizations allow a phenomenological characterization of the deuteron electromagnetic structure. They can be used to remove ambiguities in the form factors extraction from future polarization data.
Date:
February 25, 2000
Creator:
Abbott, David; Ahmidouch, Abdellah; Anklin, H.; Arvieux, J.; Ball, James P.; Beedoe, Shelton et al.
Object Type:
Article
System:
The UNT Digital Library
Pattern of Thermal Fluctuations in a Recovery Boiler Floor
The floor of a black liquor recovey boiler at a mill in central Canada has experienced cracking and delamination of the composite tubing near the spout wall and deformation of the floor panels that is most severe in the vicinity of the spout wall. One possible explanation for the observed damage is impacts of salt cake falling from the convective section onto the floor. In order to determine if such impacts do occur, strain gauges and thermocouples were installed on the boiler floor in areas where cracking and deformation were most frequent. The data obtained from these instruments indicate that brief, sudden temperature fluctuations do occur, and changes in the strain experienced by the affected tube occur simultaneously. These fluctuations appear to occur less often along the spout wall and more frequently with increasing distance from the wall. The frequency of these temperature fluctuations is insufficient for thermal fatigue to be the sole cause of the cracking observed on the tubes, but the data are consistent with what might be expected from pieces of falling salt cake.
Date:
April 25, 1999
Creator:
Abdullah, Z.; Gorog, J. P.; Keiser, J. R.; Meyers, L. E. & Swindeman, R. W.
Object Type:
Article
System:
The UNT Digital Library
Conversion Tower for Dispatchable Solar Power
Advanced Research Projects Agency-Energy project sheet summarizing general information about the High Energy Advanced Thermal Storage (HEATS) program including critical needs, innovation and advantages, impacts, and contact information. This sheet discusses new system architecture for a solar-electric conversion tower as part of the "High-Efficiency Solar-Electric Conversion Power Tower" project.
Date:
May 25, 2012
Creator:
Abengoa Solar, Inc.
Object Type:
Text
System:
The UNT Digital Library
MCNP-REN - A Monte Carlo Tool for Neutron Detector Design Without Using the Point Model
The development of neutron detectors makes extensive use of the predictions of detector response through the use of Monte Carlo techniques in conjunction with the point reactor model. Unfortunately, the point reactor model fails to accurately predict detector response in common applications. For this reason, the general Monte Carlo N-Particle code (MCNP) was modified to simulate the pulse streams that would be generated by a neutron detector and normally analyzed by a shift register. This modified code, MCNP - Random Exponentially Distributed Neutron Source (MCNP-REN), along with the Time Analysis Program (TAP) predict neutron detector response without using the point reactor model, making it unnecessary for the user to decide whether or not the assumptions of the point model are met for their application. MCNP-REN is capable of simulating standard neutron coincidence counting as well as neutron multiplicity counting. Measurements of MOX fresh fuel made using the Underwater Coincidence Counter (UWCC) as well as measurements of HEU reactor fuel using the active neutron Research Reactor Fuel Counter (RRFC) are compared with calculations. The method used in MCNP-REN is demonstrated to be fundamentally sound and shown to eliminate the need to use the point model for detector performance predictions.
Date:
July 25, 1999
Creator:
Abhold, M.E. & Baker, M.C.
Object Type:
Article
System:
The UNT Digital Library
Low Temperature and High Pressure Evaluation of Insulated Pressure Vessels for Cryogenic Hydrogen Storage
Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH{sub 2}) or ambient-temperature compressed hydrogen (CH{sub 2}). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (fuel flexibility, lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The work described here is directed at verifying that commercially available pressure vessels can be safely used to store liquid hydrogen. The use of commercially available pressure vessels significantly reduces the cost and complexity of the insulated pressure vessel development effort. This paper describes a series of tests that have been done with aluminum-lined, fiber-wrapped vessels to evaluate the damage caused by low temperature operation. All analysis and experiments to date indicate that no significant damage has resulted. Required future tests are described that will prove that no technical barriers exist to the safe use of aluminum-fiber vessels at cryogenic temperatures.
Date:
June 25, 2000
Creator:
Aceves, S.; Martinez-Frias, J. & Garcia-Villazana, O.
Object Type:
Article
System:
The UNT Digital Library
Detailed Analysis and Control Issues of Homogeneous Charge Compression Ignition (HCCI)
Homogeneous charge compression ignition (HCCI) is a new combustion technology that may develop as an alternative to diesel engines with high efficiency and low NOx and particulate matter emissions. This paper describes the HCCI research activities being currently pursued at Lawrence Livermore National Laboratory and at the University of California Berkeley. Current activities include analysis as well as experimental work.
Date:
August 25, 2002
Creator:
Aceves, Salvador M.; Flowers, Daniel L.; Martinez-Frias, Joel; Espinosa-Loza, Francisco & Dibble, Robert
Object Type:
Article
System:
The UNT Digital Library
Thin-film characterization and flaw detection. Final report, February 1, 1993--November 31, 1997
The objectives were to determine the elastic constants of thin films deposited on substrates, to measure residual stress and to detect and characterize defects in thin film substrate configurations. There are many present and potential applications of configurations consisting of a thin film deposited on a substrate. Thin films that are deposited to improve the hardness and/or the thermal properties of surfaces were of principal interest in this work. Thin film technology does, however, also include high {Tc} superconductor films, films for magnetic recording, superlattices and films for band-gap engineering and quantum devices. The studies that were carried out on this project also have relevance to these applications. Both the film and the substrate are generally anisotropic. A line-focus acoustic microscope has been used to measure the speed of surface acoustic waves (SAW) in the thin film/substrate system. This microscope has unique advantages for measurements in anisotropic media. Analytical and numerical techniques have been employed to extract the desired information on the thin film from the measured SAW data. Results include: (1) analytical and numerical techniques for the direct problem and for inverse methods; (2) measurements of homogeneous and superlattice film constants; (3) investigation of the effect of surface roughness …
Date:
February 25, 1998
Creator:
Achenbach, J. D.
Object Type:
Report
System:
The UNT Digital Library
B physics: evidence for the exclusive decay b^+/-_c -> j/psi pi^+ and measurement of the mass of the b^+/-_c meson
We report the first evidence of a fully reconstructed decay mode of the B{sub c}{sup {+-}} meson in the channel B{sub c}{sup {+-}} {yields} J/{psi}{sup {+-}}, with J/{psi} {yields} {mu}{sup +}{mu}{sup -}. The analysis is based on an integrated luminosity of 360 pb{sup -1} in p{bar p} collisions collected by the Collider Detector at Fermilab. We observe 18.9 {+-} 5.7 signal events on a background of 10.0 {+-} 1.4 events and the fit to the J/{psi}{pi}{sup {+-}} mass spectrum yields a B{sub c}{sup {+-}} mass of 6287.0 {+-} 4.8(stat) {+-} 1.1(syst) MeV/c{sup 2}.
Date:
May 25, 2005
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Exotic physics: search for scalar leptoquark pairs decaying to nu nu-bar qq-bar in p anti-p collisions at s**(1/2) = 1.96 tev
We report on a search for the pair production of scalar leptoquarks, LQ, using 191 pb{sup -1} of proton-antiproton collision data recorded by the CDF experiment during Run II of the Tevatron. The leptoquarks are sought via their decay into a neutrino and quark yielding missing transverse energy and several jets of large transverse energy. No evidence for leptoquark production is observed, and limits are set on {sigma}(p{bar p} {yields} LQ{ovr OQ}X {yields} v{bar v}q{bar q}X). Using a next-to-leading order theoretical prediction of the cross section for scalar leptoquark production, we exclude first-generation leptoquarks in the mass interval 78 to 117 GeV/c{sup 2} at the 95% confidence level for BR(LQ {yields} vq) = 100%.
Date:
October 25, 2004
Creator:
Acosta, D.
Object Type:
Report
System:
The UNT Digital Library
Effects of Particulate Debris Morphology on the Rolling Wear Behavior of All-Steel and Si(Sub 3)N(Sub 4)-Steel Bearing Element Couples
Rolling contact fatigue experiments were performed on all-steel and hybrid Si{sub 3}N{sub 4}-M50 steel rolling bearing systems using particulate contaminated lubricants. The particulate contaminants used were glycothermally synthesized {alpha}-Al{sub 2}O{sub 3} platelets or Arizona test dust. The effects of contaminant composition and morphology on rolling contact fatigue and wear behavior were explored. The effects of bearing element material properties on fatigue and wear behavior were also examined. Rolling wear behavior is related to bearing component material configuration and the type of particulate contaminant present in the lubricant. Component and particulate material properties such as hardness and elastic modulus are observed to affect rolling wear behavior. Wear mechanisms such as contact stress fatigue, indenting, cutting and plowing are observed.
Date:
January 25, 1999
Creator:
Adair, J.H.; Mecholsky, J.J., Jr. & Mitchell, D.J.
Object Type:
Article
System:
The UNT Digital Library
Sulfur Polymer Stabilization/Solidification (SPSS) Treatability of Simulated Mixed-Waste Mercury Contaminated Sludge
The Environmental Protection Agency (EPA) is currently evaluating alternative treatment standards for radioactively contaminated high mercury (Hg) subcategory wastes, which do not require the removal of mercury from the waste. The Sulfur Polymer Stabilization/Solidification (SPSS) process developed at Brookhaven National Laboratory is one of several candidate technologies capable of successfully treating various Hg waste streams. To supplement previously supplied data on treatment of soils, EPA needed additional data concerning stabilization of high Hg subcategory waste sludges. To this end, a 5000 ppm sludge surrogate, containing approximately 50 wt% water, was successfully treated by pilot-scale SPSS processing. In two process runs, 85 and 95 wt% of water was recovered from the sludge during processing. At waste loadings of 46 wt% (30 wt% dry) sludge, the treated waste form had no detectable mercury (<10 ppb) in TCLP leachates. Data gathered from the demonstration of treatment of this sludge will provide the EPA with information to support revisions to current treatment requirements for high Hg subcategory wastes.
Date:
February 25, 2002
Creator:
Adams, J. W.; Bowerman, B. S. & Kalb, P. D.
Object Type:
Article
System:
The UNT Digital Library
Letter of Intent for RPP Characterization Program Process Engineering and Hanford Analytical Services and Characterization Project
The Characterization Project level of success achieved by the River Protection Project (RPP) is determined by the effectiveness of several organizations across RPP working together. The requirements, expectations, interrelationships, and performance criteria for each of these organizations were examined in order to understand the performances necessary to achieve characterization objectives. This Letter of Intent documents the results of the above examination. It formalizes the details of interfaces, working agreements, and requirements for obtaining and transferring tank waste samples from the Tank Farm System (RPP Process Engineering, Characterization Project Operations, and RPP Quality Assurance) to the characterization laboratory complex (222-S Laboratory, Waste Sampling and Characterization Facility, and the Hanford Analytical Service Program) and for the laboratory complex analysis and reporting of analytical results.
Date:
February 25, 2000
Creator:
Adams, M. R.
Object Type:
Report
System:
The UNT Digital Library
Fundamental Studies of Recombinant Hydrogenases
This research addressed the long term goals of understanding the assembly and organization of hydrogenase enzymes, of reducing them in size and complexity, of determining structure/function relationships, including energy conservation via charge separation across membranes, and in screening for novel H2 catalysts. A key overall goal of the proposed research was to define and characterize minimal hydrogenases that are produced in high yields and are oxygen-resistant. Remarkably, in spite of decades of research carried out on hydrogenases, it is not possible to readily manipulate or design the enzyme using molecular biology approaches since a recombinant form produced in a suitable host is not available. Such resources are essential if we are to understand what constitutes a “minimal” hydrogenase and design such catalysts with certain properties, such as resistance to oxygen, extreme stability and specificity for a given electron donor. The model system for our studies is Pyrococcus furiosus, a hyperthermophile that grows optimally at 100°C, which contains three different nickel-iron [NiFe-] containing hydrogenases. Hydrogenases I and II are cytoplasmic while the other, MBH, is an integral membrane protein that functions to both evolve H2 and pump protons. Three important breakthroughs were made during the funding period with P. furiosus soluble …
Date:
January 25, 2014
Creator:
Adams, Michael W
Object Type:
Report
System:
The UNT Digital Library
Verification Survey of the Building 315 Zero Power Reactor-6 Facility, Argonne National Laboratory-East, Argonne, Illinois
Oak Ridge Institute for Science and Education (ORISE) conducted independent verification radiological survey activities at Argonne National Laboratory’s Building 315, Zero Power Reactor-6 facility in Argonne, Illinois. Independent verification survey activities included document and data reviews, alpha plus beta and gamma surface scans, alpha and beta surface activity measurements, and instrumentation comparisons. An interim letter report and a draft report, documenting the verification survey findings, were submitted to the DOE on November 8, 2006 and February 22, 2007, respectively (ORISE 2006b and 2007).
Date:
May 25, 2007
Creator:
Adams, W. C.
Object Type:
Report
System:
The UNT Digital Library
Confirmatory Survey Results for the Reactor Building Dome Upper Surfaces, Rancho Saco Nuclear Generating Station
Results from a confirmatory survey of the upper structural surfaces of the Reactor Building Dome at the Rancho Seco Nuclear Generating Station (RSNGS) performed by the Oak Ridge Institute for Science and Education for the NRC. Also includes results of interlaboratory comparison analyses on several archived soil samples that would be provided by RSNGS personnel. The confirmatory surveys were performed on June 7 and 8, 2006.
Date:
October 25, 2006
Creator:
Adams, Wade C.
Object Type:
Report
System:
The UNT Digital Library
Development and Testing of the NIF Prototype Module
The NIF Power Conditioning System (PCS) is required to deliver -68 kJ to each of the 3840 flashlamp pairs in the NIF laser in a current pulse with a peak of -500 kA and rise time of- 150 µs. The PCS will consist of 192 modules each of which drive 20 lamp-pairs. Each module will basically be a 6 rnF capacitor bank with a nominal charge voltage of 23.5 kV which is switched by a single pressurized air gas switch to 20 RG-220 cables that are connected to individual lamp loads. In addition each module will have a number of subsystems including; a lamp pre-ionization system, power supplies, isolation circuits, trigger systems, safety dump systems, gas system, and an embedded control system. A module will also include components whose primary function is to limit fault currents and thus minimize collateral damage in faults. In the Prototype Development and Testing effort at Sandia National Laboratories all of these were integrated into a single system and proper fimctionality was demonstrated. Extensive testing was done at nominal operating levels into resistive dummy loads and some testing in fault modes was also done. A description of the system and a summary of testing is …
Date:
June 25, 1999
Creator:
Adcock, J.; Harjes, C.; Mowrer, G. & Wilson, M.
Object Type:
Article
System:
The UNT Digital Library
Development of a video-based slurry sensor for on-line ash analysis. Technical progress report, third quarter, April 1, 1995--June 30, 1995
Automatic control of fine coal cleaning circuits has traditionally been limited by the lack of sensors for on-line ash analysis. Although several nuclear-based analyzers are available, none have seen widespread acceptance. This is largely due to the fact that nuclear sensors are expensive and tend to be influenced by changes in seam type and pyrite content Recently, researchers at VPI&SU have developed an optical sensor for phosphate analysis. The sensor uses image processing technology to analyze video images of phosphate ore. It is currently being used by Texas gulf for off-line analysis of dry flotation concentrates. The primary advantages of optical sensors over nuclear sensors are that they are significantly cheaper, are not subject to measurement variations due to changes in high atomic number minerals, are inherently safer and require no special radiation permitting. The purpose of this work is to apply the knowledge gained in the development of an optical phosphate analyzer to the development of an on-line ash analyzer for fine coal slurries. During the past quarter, a new prototype sample presentation system for the optical analyzer has been developed. This new approach appears to solve the problems encountered with previous prototypes. A qualitative comparison of the images …
Date:
July 25, 1995
Creator:
Adel, G. T. & Luttrell, G. H.
Object Type:
Report
System:
The UNT Digital Library
Optimization of the LCLS Single Pulse Shutter
A mechanical shutter which operates on demand is used to isolate a single pulse from a 120 Hz X-ray source. This is accomplished with a mechanical shutter which is triggered on demand with frequencies ranging from 0 to 10 Hz. The single pulse shutter is an iron blade that oscillates on a pivot in response to a force generated by a pair of pulsed electromagnets (current driven teeter-totter). To isolate an individual pulse from the X-ray beam, the motion of the mechanical shutter should be synchronized in such a way that it allows a single pulse to pass through the aperture and blocks the other incoming pulses. Two consecutive pulses are only {approx} 8 ms apart and the shutter is required to complete one full cycle such that no two pulses pass through the opening. Also the opening of the shutter blade needs to be at least 4 mm so that a 1 mm diameter rms Gaussian beam can pass through without modulation. However, the 4 mm opening is difficult to obtain due to blade rebound and oscillation of the blade after colliding with the electromagnet. The purpose of this project is to minimize and/or totally eliminate the rebound of …
Date:
August 25, 2010
Creator:
Adera, Solomon & /Georgia Tech., Atlanta /SLAC
Object Type:
Report
System:
The UNT Digital Library