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Record of Technical Change No.1 for ``Fluid Management Plan for the Project Shoal Area Off-sites Project''
This Record of Technical Change provides updates to the technical information included in the ``Fluid Management Plan for the Project Shoal Area Off-sites Project,'' April 1999
Date:
November 22, 1999
Creator:
/NV, USDOE
Object Type:
Report
System:
The UNT Digital Library
Angular quadratures for improved transport computations
This paper introduces new octant-range, composite-type Gauss and mid-point rule angular quadrature formulas for neutron and photon transport computations. A generalization to octant-range quadratures is also introduced in order to allow for discontinuities at material interfaces for two- and three-dimensional transport problems which can be modeled with 60-degree triangular or hexagonal mesh subdivisions in the x-y plane.
Date:
July 22, 1999
Creator:
Abu-Shumays, I.K.
Object Type:
Article
System:
The UNT Digital Library
Fuel processing for fuel cell powered vehicles.
A number of auto companies have announced plans to have fuel cell powered vehicles on the road by the year 2004. The low-temperature polymer electrolyte fuel cells to be used in these vehicles require high quality hydrogen. Without a hydrogen-refueling infrastructure, these vehicles need to convert the available hydrocarbon fuels into a hydrogen-rich gas on-board the vehicle. Earlier analysis has shown that fuel processors based on partial oxidation reforming are well suited to meet the size and weight targets and the other performance-related needs of on-board fuel processors for light-duty fuel cell vehicles (1).
Date:
January 22, 1999
Creator:
Ahmed, S.; Wilkenhoener, R.; Lee, S. H. D.; Carter, J. D.; Kumar, R. & Krumpelt, M.
Object Type:
Article
System:
The UNT Digital Library
Correlating radiation exposure with embrittlement: Comparative studies of electron- and neutron-irradiated pressure vessel alloys
Comparative experiments using high energy (10 MeV) electrons and test reactor neutrons have been undertaken to understand the role that primary damage state has on hardening (embrittlement) induced by irradiation at 300 C. Electrons produce displacement damage primarily by low energy atomic recoils, while fast neutrons produce displacements from considerably higher energy recoils. Comparison of changes resulting from neutron irradiation, in which nascent point defect clusters can form in dense cascades, with electron irradiation, where cascade formation is minimized, can provide insight into the role that the in-cascade point defect clusters have on the mechanisms of embrittlement. Tensile property changes induced by 10 MeV electrons or test reactor neutron irradiations of unalloyed iron and an Fe-O.9 wt.% Cu-1.0 wt.% Mn alloy were examined in the damage range of 9.0 x 10{sup {minus}5} dpa to 1.5 x 10{sup {minus}2} dpa. The results show the ternary alloy experienced substantially greater embrittlement in both the electron and neutron irradiate samples relative to unalloyed iron. Despite their disparate nature of defect production similar embrittlement trends with increasing radiation damage were observed for electrons and neutrons in both the ternary and unalloyed iron.
Date:
December 22, 1999
Creator:
Alexander, D. E.; Rehn, L. E.; Odette, G. R.; Lucas, G. E.; Klingensmith, D. & Gragg, D.
Object Type:
Article
System:
The UNT Digital Library
Intracavity Frequency Doubling of a Diode-Pumped, External Cavity, Surface Emitting Semiconductor Laser
The authors present a compact, robust, solid-state blue light (490 nm) source capable of greater than 5 mW of output in a TEM{sub 00} mode. This device is an optically pumped, vertical external-cavity surface-emitting laser (VECSEL) with an intracavity frequency doubling crystal.
Date:
April 22, 1999
Creator:
Alford, W. J.; Allerman, A. A.; Crawford, M. H. & Raymond, T. D.
Object Type:
Article
System:
The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 89, Ed. 1 Friday, January 22, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
January 22, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 110, Ed. 1 Monday, February 22, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
February 22, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 125, Ed. 1 Monday, March 22, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
March 22, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
The Oklahoma Daily (Norman, Okla.), Vol. 83, No. 146, Ed. 1 Thursday, April 22, 1999
Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date:
April 22, 1999
Creator:
Allam, Heather
Object Type:
Newspaper
System:
The Gateway to Oklahoma History
Searching for R-Parity Violation at Run-II of the Tevatron.
The authors present an outlook for possible discovery of supersymmetry with broken R-parity at Run II of the Tevatron. They first present a review of the literature and an update of the experimental bounds. In turn they then discuss the following processes: (1) resonant slepton production followed by R{sub P} decay, (a) via LQD{sup c} and (b) via LLE{sup c}; (2) how to distinguish resonant slepton production from Z{prime} or W{prime} production; (3) resonant slepton production followed by the decay to neutralino LSP, which decays via LQD{sup c}; (4) resonant stop production followed by the decay to a chargino, which cascades to the neutralino LSP; (5) gluino pair production followed by the cascade decay to charm squarks which decay directly via L{sub 1}Q{sub 2}D{sub 1}{sup c}; (6) squark pair production followed by the cascade decay to the neutralino LSP which decays via L{sub 1}Q{sub 2}D{sub 1}{sup c}; (7) MSSM pair production followed by the cascade decay to the LSP which decays (a) via LLE{sup c}, (b) via LQD{sup c}, and (c) via U{sup c}D{sup c}D{sup c}, respectively; and (8) top quark and top squark decays in spontaneous R{sub P}.
Date:
June 22, 1999
Creator:
Allanach, B.; Banerjee, S.; Berger, E. L.; Chertok, M.; de Campos, F.; Dedes, A. et al.
Object Type:
Article
System:
The UNT Digital Library
Parallel-Plate Electrostatic Dual Mass Oscillator
A surface-micromachined two-degree-of-freedom system that was driven by parallel-plate actuation at antiresonance was demonstrated. The system consisted of an absorbing mass connected by folded springs to a drive mass. The system demonstrated substantial motion amplification at antiresonance. The absorber mass amplitudes were 0.8-0.85 pm at atmospheric pressure while the drive mass amplitudes were below 0.1 pm. Larger absorber mass amplitudes were not possible because of spring softening in the drive mass springs. Simple theory of the dual-mass oscillator has indicated that the absorber mass may be insensitive to limited variations in strain and damping. This needs experimental verification. Resonant and antiresonant frequencies were measured and compared to the designed values. Resonant frequency measurements were difficult to compare to the design calculations because of time-varying spring softening terms that were caused by the drive configuration. Antiresonant frequency measurements were close to the design value of 5.1 kHz. The antiresonant frequency was not dependent on spring softening. The measured absorber mass displacement at antiresonance was compared to computer simulated results. The measured value was significantly greater, possibly due to neglecting fringe fields in the force expression used in the simulation.
Date:
July 22, 1999
Creator:
Allen, James J.; Dyck, Christopher W. & Huber, Robert J.
Object Type:
Article
System:
The UNT Digital Library
Observation of the moon shadow in deep underground muon flux.
A shadow of the moon, with a statistical significance of 5{sigma}, has been observed in the underground muon flux at a depth of 2090 mwe using the Soudan 2 detector. The angular resolution of the detector is well described by a Gaussian with {sigma} {le}0.3{degree}. The position of the shadow confirms the alignment of the detector to better than 0.15{degree}. This alignment has remained stable during 10 years of data taking from 1989 through 1998.
Date:
June 22, 1999
Creator:
Allison, W. W. M.; Alner, G. J.; Ayres, D. S.; Cobb, J. H.; Fields, T. H.; Goodman, M. C. et al.
Object Type:
Article
System:
The UNT Digital Library
Hierarchies Without Symmetries from Extra Dimensions
It is commonly thought that small couplings in a low-energy theory, such as those needed for the fermion mass hierarchy or proton stability, must originate from symmetries in a high-energy theory. We show that this expectation is violated in theories where the Standard Model fields are confined to a thick wall in extra dimensions, with the fermions ''stuck'' at different points in the wall. Couplings between them are then suppressed due to the exponentially small overlaps of their wave functions. This provides a framework for understanding both the fermion mass hierarchy and proton stability without imposing symmetries, but rather in terms of higher dimensional geography. A model independent prediction of this scenario is non-universal couplings of the Standard Model fermions to the ''Kaluza-Klein'' excitations of the gauge fields. This allows a measurement of the fermion locations in the extra dimensions at the LHC or NLC if the wall thickness is close to the TeV scale.
Date:
March 22, 1999
Creator:
Arkani-Hamed, Nima
Object Type:
Report
System:
The UNT Digital Library
P2Pro(RSM) : a computerized management tool for implementing DOE's authorized release process for radioactive scrap metals.
Within the next few decades, several hundred thousand tons of metal and several million cubic meters of concrete are expected to be removed from nuclear facilities across the US Department of Energy (DOE) complex as a result of decontamination and decommissioning (D&D) activities. These materials, together with large quantities of tools, equipment, and other items that are commonly recovered from site cleanup or D&D activities, constitute non-real properties that warrant consideration for release from regulatory control for reuse or recycle, as permitted and practiced under current DOE policy. The provisions for implementing this policy are contained in the Draft Handbook for Controlling Release for Reuse or Recycle of Non-Real Property Containing Residual Radioactive Material published by DOE in 1997 and distributed to DOE Field Offices for interim use and implementation. This manual describes a computer management tool, P2Pro(RSM), that implements the first 5 steps of the 10-step process stipulated by the Handbook. P2Pro(RSM) combines an easy-to-use Windows interface with a comprehensive database to facilitate the development of authorized release limits for non-real property.
Date:
July 22, 1999
Creator:
Arnish, J.; Chen, S. Y.; Kamboj, S. & Nieves, L.
Object Type:
Report
System:
The UNT Digital Library
Equation-of-State Measurements with Z-Pinch Sources
Validation of material models in a variety of scientific and technological applications requires accurate data regarding the high-pressure thermodynamic and mechanical properties. Traditional laboratory techniques for striking these measurements involve light gas guns to generate the required thermodynamic states, and the use of high-resolution time-resolved diagnostics to measure the desired material properties. EOS and constitutive material properties of importance to modeling needs include high-pressure Hugoniot curves and off-Hugoniot properties, such as. material strength and isentropic compression and decompression [1]. Conventional light gas guns are limited to impact pressures of about 7 Mbar in high-impedance materials. Pulsed radiation sources, such as high-intensity lasers, and pulsed power techniques significantly extend the accessible pressures and are becoming accepted methods for meeting the needs of material models in regimes inaccessible by gas guns. A present limitation of these new approaches is that samples must necessarily be small, typically a few tens of microns in thickness, which severely limits the accuracy of EOS measurements that can be made and also the ability to perform a variety of off-Hugoniot measurements. However, recent advances in z-pinch techniques for high-pressure material response studies provide potential opportunities for achieving accuracies comparable with gas guns because of the significantly larger …
Date:
July 22, 1999
Creator:
Asay, J. R.; Hall, C.; Bailey, J. E.; Knudson, M. D.; Holland, K. G.; Hanson, D. L. et al.
Object Type:
Article
System:
The UNT Digital Library
A simple way of characterizing x-ray downwards-deflecting mirror-bender assemblies using the long trace profiler
A simple device composed of a modular double-pentaprism system that enables the long trace profiler (LTP) to measure mirrors in nonconventional ways, i.e., in the vertical-downward and sideways positions, has been devised and implemented in the Advanced Photon Source (APS) long trace profiler (LTP II). The systems is very useful in calibrating mirror-bender assemblies. This paper describes the system and gives results of measurements performed with it on a mirror used at the APS.
Date:
November 22, 1999
Creator:
Assoufid, L. & Her, P.
Object Type:
Article
System:
The UNT Digital Library
Computational Modeling of Heterogeneous Reactive Materials at the Mesoscale
The mesoscopic processes of consolidation, deformation and reaction of shocked porous energetic materials are studied using shock physics analysis of impact on a collection of discrete ''crystals.'' Highly resolved three-dimensional CTH simulations indicate that rapid deformation occurs at material contact points causing large amplitude fluctuations of stress states with wavelengths of the order of several particle diameters. Localization of energy produces ''hot-spots'' due to shock focusing and plastic work near internal boundaries as material flows into interstitial regions. Numerical experiments indicate that ''hot-spots'' are strongly influenced by multiple crystal interactions. Chemical reaction processes also produce multiple wave structures associated with particle distribution effects. This study provides new insights into the micromechanical behavior of heterogeneous energetic materials strongly suggesting that initiation and sustained reaction of shocked heterogeneous materials involves states distinctly different from single jump state descriptions.
Date:
September 22, 1999
Creator:
BAER, MARVIN R.
Object Type:
Article
System:
The UNT Digital Library
The Effect of Ramp Rate on the C49 to C54 Titanium Disilicide Phase Transformation from Ti and Ti(Ta)
The C49 to C54 TiSi{sub 2} transformation temperature is shown to be reduced by increasing the ramp rate during rapid thermal processing and this effect is more pronounced for thinner initial Ti and Ti(Ta) films. Experiments were performed on blanket wafers and on wafers that had patterned polycrystalline Si lines with Si{sub 3}N{sub 4} sidewall spacers. Changing the ramp rate caused no change in the transformation temperature for 60 nm blanket Ti films. For blanket Ti films of 25 or 40 nm, however, increasing the ramp rate from 7 to 180 C/s decreased the transformation temperature by 15 C. Studies of patterned lines indicate that sheet resistance of narrow lines is reduced by increased ramp rates for both Ti and Ti(Ta) films, especially as the linewidths decrease below 0.4 {micro}m. This improvement is particularly pronounced for the thinnest Ti(Ta) films, which exhibited almost no linewidth effect after being annealed with a ramp rate of 75 C/s.
Date:
September 22, 1999
Creator:
BAILEY, GLENN A.; HU, YAO ZHI; SMITH, PAUL M. & TAY, SING PIN
Object Type:
Article
System:
The UNT Digital Library
A Combined Statistical-Microstructural Model for Simulation of Sintering
Sintering theory has been developed either as the application of complex diffusion mechanisms to a simple geometry or as the deformation and shrinkage of a continuum body. They present a model that can treat in detail both the evolution of microstructure and the sintering mechanisms, on the mesoscale, so that constitutive equations with detail microstructural information can be generated. The model is capable of simulating vacancy diffusion by grain boundary diffusion, annihilation of vacancies at grain boundaries resulting in densification, and coarsening of the microstructural features. In this paper, they review the stereological theory of sintering and its application to microstructural evolution and the diffusion mechanism, which lead to sintering. They then demonstrate how these stereological concepts and diffusion mechanisms were incorporated into a kinetic Monte Carlo model to simulate sintering. Finally, they discuss the limitations of this model.
Date:
October 22, 1999
Creator:
BRAGINSKY,MICHAEL V.; DEHOFF,ROBERT T.; OLEVSKY,EUGENE A. & TIKARE,VEENA
Object Type:
Article
System:
The UNT Digital Library
House Rules Affecting Committees
This report identifies and summarizes these and other rules and directives affecting committee powers, authority, activities, and operations.
Date:
February 22, 1999
Creator:
Bach, Stanley & Hardy-Vincent, Carol
Object Type:
Report
System:
The UNT Digital Library
House Rules Affecting Committees
House Rules, especially Rules X-XIII, govern the authority and operations of its committees and subcommittees. This report identifies and summarizes these and other rules and directives affecting committee powers, authority, activities, and operations.
Date:
February 22, 1999
Creator:
Bach, Stanley & Hardy-Vincent, Carol
Object Type:
Report
System:
The UNT Digital Library
Development of scaling prediction tools for solar hot water systems. Part B - Development of an improved calcium carbonate scaling rate model - An experimental and analytical investigation
None
Date:
September 22, 1999
Creator:
Baker, Derek
Object Type:
Report
System:
The UNT Digital Library
Mixed-conducting dense ceramics for gas separation applications.
Mixed-conducting (electronic and ionic conducting) dense ceramics are used in many applications, including fuel cells, gas separation membranes, batteries, sensors, and electrocatalysis. This paper describes mixed-conducting ceramic membranes that are being developed to selectively remove oxygen and hydrogen from gas streams in a nongalvanic mode of operation (i.e., with no electrodes or external power supply). Ceramic membranes made of Sr-Fe-Co oxide (SFC), which exhibits high combined electronic and oxygen ionic conductivities, can be used for high-purity oxygen separation and/or partial oxidation of methane to synthesis gas (syngas, a mixture of CO and H{sub 2}). The electronic and ionic conductivities of SFC were found to be comparable in magnitude. Steady-state oxygen permeability of SFC has been measured as a function of oxygen-partial-pressure gradient and temperature. For an {approx}3-mm-thick membrane, the oxygen permeability was {approx}2.5 scc{center_dot}cm{sup {minus}2}{center_dot}min{sup {minus}1} at 900 C. Oxygen permeation increases as membrane thickness decreases. Tubular SFC membranes have been fabricated and operated at 900 C for {approx}1000 h in converting methane into syngas. The oxygen permeated through the membrane reacted with methane in the presence of a catalyst and produced syngas. We also studied the transport properties of yttria-doped BaCeO{sub 3{minus}{delta}} (BCY) by impedance spectroscopy and open-cell voltage …
Date:
June 22, 1999
Creator:
Balachandran, U.; Dorris, S. E.; Dusek, J. T.; Guan, J.; Liu, M.; Ma, B. et al.
Object Type:
Article
System:
The UNT Digital Library
A method to remove Ammonia using a Proton-Conducting Ceramic Membrane
An apparatus and method for decomposing NH{sub 3}. A fluid containing NH{sub 3} is passed in contact with a tubular membrane that is a homogeneous mixture of a ceramic and a first metal, with the ceramic being selected from one or more of a cerate having the formula of M' Ce{sub 1-x} M''O{sub 3-{delta}}, zirconates having the formula M'Zr{sub 1-x} M''3-{delta}, stannates having the formula M'Sn{sub 1-x}M''O{sub 3}-{delta}, where M' is a group IIA metal, M'' is a dopant metal of one or more of Ca, Y, Yb, In, Nd, Gd or mixtures thereof and {delta} is a variable depending on the concentration of dopant and is in the range of from 0.001 to 0.5, the first metal is a group VIII or group IB element selected from the group consisting of Pt, Ag, Pd, Fe, Co, Cr, Mn, V, Ni, Au, Cu, Rh, Ru and mixtures thereof. The tubular membrane has a catalytic metal on the side thereof in contact with the fluid containing NH{sub 3} which is effective to cause NH{sub 3} to decompose to N{sub 2} and H{sub 2}. When the H{sub 2} contacts the membrane, H{sup +} ions are formed which pass through the membrane driving …
Date:
September 22, 1999
Creator:
Balachandran, Uthamalingam & Bose, Arun C.
Object Type:
Patent
System:
The UNT Digital Library