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Determination of performance criteria for high-level solidified nuclear waste from the commercial nuclear fuel cycle: a probabilistic safety analysis (open access)

Determination of performance criteria for high-level solidified nuclear waste from the commercial nuclear fuel cycle: a probabilistic safety analysis

To minimize the radiological risk from the operation of a waste management system for the safe disposal of high-level waste, performance characteristics of the solidified waste form must be specified. The minimum waste form characteristics that must be specified are the radionuclide volatilization fraction, airborne particulate dispersion fraction, and the aqueous dissolution characteristics. The results indicate that the pre-emplacement environs are more limiting in establishing the waste form performance criteria than the post-emplacement environs. The actual values of expected risk are sensitive to modeling assumptions and data base uncertainties. The transportation step appears to be the most limiting in determining the required performance characteristics.
Date: March 30, 1978
Creator: Heckman, R.A.
System: The UNT Digital Library
Methods and calculations for regional, continental, and global dose assessments from a hypothetical fuel reprocessing facility (open access)

Methods and calculations for regional, continental, and global dose assessments from a hypothetical fuel reprocessing facility

The Savannah River Laboratory (SRL) is coordinating an interlaboratory effort to provide, test, and use state-of-the-art methods for calculating the environmental impact to an offsite population from the normal releases of radionuclides during the routine operation of a fuel-reprocessing plant. Results of this effort are the estimated doses to regional, continental, and global populations. Estimates are based upon operation of a hypothetical reprocessing plant at a site in the southeastern United States. The hypothetical plant will reprocess fuel used at a burn rate of 30 megawatts/metric ton and a burnup of 33,000 megawatt days/metric ton. All fuel will have been cooled for at least 365 days. The plant will have a 10 metric ton/day capacity and an assumed 3000 metric ton/year (82 percent online plant operation) output. Lifetime of the plant is assumed to be 40 years.
Date: March 19, 1978
Creator: Schubert, J. F.; Kern, C. D.; Cooper, R. E. & Watts, J. R.
System: The UNT Digital Library
Precision fiducialization of transport components (open access)

Precision fiducialization of transport components

The Final Focus Test Beam (FFTB) is a transport line designed to test both concept and advanced technology for application to future linear colliders. It is currently under construction at SLAC in the central beam line. Most of the quadrupoles of the FFTB have ab initio alignment tolerances of less than 30 microns, if the planned for beam based alignment tuning procedure is to converge. For such placement tolerances to have any meaning requires that the coordinates of the effective centers, seen by the beam particles, be tansferred to tooling (that can be reached by mechanical or optical alignment methods) located on the outside of the components to comparable or better values. We have constructed an apparatus that simultaneously locates to micron tolerances, the effective magnetic center of fussing lenses, as well as the electrical center of beam position monitors (BPM) imbedded therein, and once located, for transferring these coordinates to specially mounted tooling frames that supported the external retroreflectors used in a laser tracker based alignment of the beam line. Details of construction as well as experimental results from the method are presented.
Date: March 1, 1992
Creator: Fischer, G. E.; Bressler, V. E.; Cobb, J. K.; Jensen, D. R.; Ruland, R. E.; Walz, H. V. et al.
System: The UNT Digital Library
Comparing the Floating Point Systems, Inc. AP-190L to representative scientific computers: some benchmark results (open access)

Comparing the Floating Point Systems, Inc. AP-190L to representative scientific computers: some benchmark results

Results are presented of comparative timing tests made by running a typical FORTRAN physics simulation code on the following machines: DEC PDP-10 with KI processor; DEC PDP-10, KI processor, and FPS AP-190L; CDC 7600; and CRAY-1. Factors such as DMA overhead, code size for the AP-190L, and the relative utilization of floating point functional units for the different machines are discussed. 1 table.
Date: March 27, 1980
Creator: Brengle, T.A. & Maron, N.
System: The UNT Digital Library
Fifteenth LAMPF users group meeting (open access)

Fifteenth LAMPF users group meeting

The Fifteenth LAMPF Users Group Meeting was held November 2-3, 1981 at the Clinton P. Anderson Meson Physical Facility. The program of papers scheduled to be presented was amended to include a Report from Washington by Clarence R. Richardson, US Department of Energy. The general meeting ended with a round-table working group discussion concerning the Planning for a Kaon Factory. Individual items from the meeting were prepared separately for the data base.
Date: March 1, 1982
Creator: Cochran, D.R.F. (comp.)
System: The UNT Digital Library
State-of-the-art review of phase equilibria (open access)

State-of-the-art review of phase equilibria

High-pressure phase-equilibrium calculations using an equation of state are more sensitive to the mixing rules than to details in the effect of density or temperature on pressure. Attention must be given to the problem of how to extend equations of state to mixtures. One possible technique is provided by perturbation theory; another by superposition of chemical equilibria. At low or moderate pressures, vapor-phase corrections are often important. When specific intermolecular forces produce formation of molecular aggregates, strong deviations from ideal-gas behavior can be significant even at pressures well below 1 bar. When vapor-liquid equilibrium data are reduced using conventional expressions for the excess Gibbs energy, the resulting binary parameters tend to be partially correlated, it difficult, but no impossible, to calculate ternary liquid-liquid equilibria using binary parameters only. New models for calculating properties of liquid-phase mixtures mist allow for changes in free volume to give consideration to the effect of mixing on changes in rotational and vibrational degrees of freedom. Liquid-phase volumetric effects are also important in describing the solubilities of gases in solvent mixtures. Therefore, future liquid-phase models should incorporate a liquid-phase equation of state, either of the van der Waals type or, perhaps, as given by the direct-correlation …
Date: March 1, 1980
Creator: Prausnitz, J.M.
System: The UNT Digital Library
The polarized electron gun for the SLC (open access)

The polarized electron gun for the SLC

A new polarized electron gun for use on the SLC at SLAC has been built and tested. It is a diode gun with a laser driven GaAs photocathode. It is designed to provide short (2ns) pulses of 10 A at 160 kV at 120 Hz. The design features of the gun and results from a testing program on a new and dedicated beam line are presented. Early results from operation on the SLC will also be shown.
Date: March 1, 1992
Creator: Schultz, D. C.; Clendenin, J.; Frisch, J.; Hoyt, E.; Klaisner, L.; Woods, M. et al.
System: The UNT Digital Library
Sensitivity of the eastern United States to acid precipitation impacts on surface waters (open access)

Sensitivity of the eastern United States to acid precipitation impacts on surface waters

Efforts to identify areas of the United States where soils and freshwaters might be sensitive to acidification have proceeded from analyses of large scale geologic maps. These are useful in a general way but a finer scale analysis has been needed. We have carried out such an analysis for the eastern United States based primarily on geologic maps of scales 1:250,000 to 1:500,000. This report is a synopsis of and excerpted from that effort. Other workers have prepared maps on a similar scale of the soils to a depth of 25 cm, and we anticipate that both sets of maps will be merged into a combined analysis of sensitivity. Other factors important in controlling acidification of soils and freshwaters include hydrologic charcteristics of the terrain, such as: soil porosity or permeability; water residence time in soil; temporal variation in precipitation rate, chemistry and volume; regional temperature patterns; and topography.
Date: March 1, 1980
Creator: Hendrey, G. R.; Galloway, J. N.; Norton, S. A. & Schofield, C. L.
System: The UNT Digital Library
Doublet III neutral beam injector test tank cryopanel design (open access)

Doublet III neutral beam injector test tank cryopanel design

A simple condensing cryopanel has been designed for the Doublet III neutral beam test tank with a 320,000 liters per second pumping capacity for hydrogen. This maintains a vacuum in the test tank which simulates the Doublet III vessel, 1.3 x 10/sup -3/ Pa (approx.10/sup -5/ torr). The hydrogen gas load comes from the beam striking the test tank calorimeter and amounts to about 7.2 torr liters per second. The cryopanel is cylindrical shaped with a liquid helium (LHe) surface that pumps through liquid nitrogen (LN) cooled aluminum chevrons located in squirrel-cage fashion around the inside surface of the cylinder. The LHe cooled surface is a smooth cylinder 2.09m in diameter by .69m long with LHe flowing in a approx. 1mm annular space between concentric cylinders. The chevrons which are not blackened are cooled from each end with LN flowing in ring manifolds that serve as the primary cryopanel structure. The LHe is force fed at 55.2 kPa remaining in the liquid phase through the panel. External heat exchanger capability permits use of helium at 3.8 to 4.2/sup 0/K. Normal operating flow rate is 1.4 g/sec for a heat load expected to be 12.2 W total.
Date: March 1, 1980
Creator: Doll, D.W.; Kamperschroer, J.H. & Arend, P.V.
System: The UNT Digital Library
Fatigue and environmentally assisted cracking in light water reactors (open access)

Fatigue and environmentally assisted cracking in light water reactors

Fatigue and stress corrosion cracking (SCC) for low-alloy steel used in piping and in steam generator and reactor pressure vessels have been investigated. Fatigue data were obtained on medium-sulfur-content A533-Gr B and A106-Gr B steels in high-purity (HP) deoxygenated water, in simulated pressurized water reactor water, and in air. Analytical studies focused on the behavior of carbon steels in boiling water reactor (BWR) environments. Crack-growth rates of composite fracture-mechanics specimens of A533-Gr B/Inconel-182/Inconel-600 (plated with nickel) and homogeneous specimens of A533-Gr B steel were determined under small-amplitude cyclic loading in HP water with {approx}300 pbb dissolved oxygen. Radiation-induced segregation and irradiation-assisted SCC of Type 304 SS after accumulation of relatively high fluence also have been investigated. Microchemical and microstructural changes in HP and commercial-purity Type 304 SS specimens from control-blade absorber tubes used in two operating BWRs were studied by Auger electron spectroscopy and scanning electron microscopy, and slow-strain-rate tensile tests were conducted on tubular specimens in air and in simulated BWR water at 289{degrees}C.
Date: March 1, 1992
Creator: Kassner, T.F.; Ruther, W.E.; Chung, H.M.; Hicks, P.D.; Hins, A.G.; Park, J.Y. et al.
System: The UNT Digital Library
Design and operation of the multipulse Thomson scattering diagnostic on DIII-D (open access)

Design and operation of the multipulse Thomson scattering diagnostic on DIII-D

This paper describes the design and operation of a 40 spatial channel Thomson scattering system that uses multiple 20 Hz Nd:YAG lasers to measure the electron temperature and density profiles periodically throughout an entire plasma discharge. As many as eight lasers may be fired alternately for an average measurement frequency of 160 Hz, or they may be fired in rapid succession (< 10 kHz), producing a burst of pulses for measuring transient events. The high spatial resolution (1.3 cm) and wide dynamic range (10 eV to 20 keV) enable this system to resolve large electron density and temperature gradients formed at the plasma edge and in the scrape-off-layer during H-mode operation. These features provide a formidable tool for studying L-H transitions, edge localized modes (ELMs), beta limits, transport, and disruptions in an efficient manner suitable for large tokamak operation where shot-to-shot scans are impractical. The scattered light is dispersed by interference filter polychromators and detected by silicon avalanche photodiodes. Laser control and data acquisition are performed in real-time by a VME based microcomputer. Data analysis is performed by a MicroVAX 3400. Additional features of this system include real-time analysis capability, full statistical treatment of error bars based on the measured …
Date: March 1, 1992
Creator: Carlstrom, T. N.; Campbell, G. L.; DeBoo, J. C.; Evanko, R.; Greenfield, C. M.; Haskovec, J. et al.
System: The UNT Digital Library
Failure of sheathed thermocouples due to thermal cycling (open access)

Failure of sheathed thermocouples due to thermal cycling

Open circuit failures (up to 100%) in small-diameter thermocouples used in electrically heated nuclear fuel rod simulator prototypes during thermal cycling tests were investigated to determine the cause(s) of the failures. The experiments conducted to determine the relative effects of differential thermal expansion, wire size, grain size, and manufacturing technology are described. It was concluded that the large grain size and embrittlement which result from certain common manufacturing annealing and drawing procedures were a major contributing factor in the breakage of the thermocouple wires.
Date: March 1, 1982
Creator: Anderson, R.L. & Ludwig, R.L.
System: The UNT Digital Library
Arming and firing system for DISTANT RUNNER (open access)

Arming and firing system for DISTANT RUNNER

Sandia A and F systems Division 1132 provided arming and firing support for the DISTANT RUNNER Test Program at White Sands Missile Range. This report describes the field support and the firing system that was used.
Date: March 1, 1982
Creator: Skenandore, L. H. & Johnson, J. P.
System: The UNT Digital Library
Fast-timing methods for semiconductor detectors (open access)

Fast-timing methods for semiconductor detectors

The basic parameters are discussed which determine the accuracy of timing measurements and their effect in a practical application, specifically timing with thin-surface barrier detectors. The discussion focusses on properties of the detector, low-noise amplifiers, trigger circuits and time converters. New material presented in this paper includes bipolar transistor input stages with noise performance superior to currently available FETs, noiseless input terminations in sub-nanosecond preamplifiers and methods using transmission lines to couple the detector to remotely mounted preamplifiers. Trigger circuits are characterized in terms of effective rise time, equivalent input noise and residual jitter.
Date: March 1, 1982
Creator: Spieler, H.
System: The UNT Digital Library
Methane or methanol via catalytic gasification of biomass (open access)

Methane or methanol via catalytic gasification of biomass

Methane and methanol synthesis gas can be produced by steam gasification of biomass in the presence of appropriate catalysts. A 5 cm diameter reactor has been used to determine the desired catalysts and operating temperature. A process development unit (PDU) has demonstrated steam gasification of biomass with catalysts at rates up to 35 kg per hour. Methane yields of 0.28 nm/sup 3/ per kg of dry wood were produced in the small laboratory reactor. Further methanation of the product gas mixture can increase methane yields to 0.33 nm/sup 3//kg. The catalyst system is nickel and silica-alumina. The preferred reactor operating temperature is 500 to 550/sup 0/C. Tests have been at atmospheric pressure. The PDU performance has confirmed results obtained in the laboratory. Methanol synthesis gas can be produced in a single stage reactor at 750 to 850/sup 0/C by steam gasification of wood with silica-alumina and nickel catalysts present. From this gas, up to 0.6 kg of methanol can be produced per kg of wood. Gasification of the wood to produce synthesis gas has been demonstrated in the laboratory scale reactor, but remains to be successfully done using the PDU. Catalyst deactivation rates and regeneration schemes must be determined in …
Date: March 1, 1980
Creator: Mitchell, D. H.; Mudge, L. K.; Robertus, R. J.; Weber, S. L. & Sealock, L. J. Jr.
System: The UNT Digital Library
Transient plasma estimation: a noise cancelling/identification approach (open access)

Transient plasma estimation: a noise cancelling/identification approach

The application of a noise cancelling technique to extract energy storage information from sensors occurring during fusion reactor experiments on the Tandem Mirror Experiment-Upgrade (TMX-U) at the Lawrence Livermore National Laboratory (LLNL) is examined. We show how this technique can be used to decrease the uncertainty in the corresponding sensor measurements used for diagnostics in both real-time and post-experimental environments. We analyze the performance of algorithm on the sensor data and discuss the various tradeoffs. The algorithm suggested is designed using SIG, an interactive signal processing package developed at LLNL.
Date: March 1, 1985
Creator: Candy, J.V.; Casper, T. & Kane, R.
System: The UNT Digital Library
Fabrication and test of prototype ring magnets for the ALS (Advanced Light Source) (open access)

Fabrication and test of prototype ring magnets for the ALS (Advanced Light Source)

Prototype Models for the Advanced Light Source (ALS) Booster Dipole, Quadrupole and Sextupole and the Storage Ring Gradient Magnet, Quadrupole and Sextupole have been constructed. The Booster Magnet Prototypes have been tested. The Storage Ring Magnets are presently undergoing tests and magnetic measurements. This paper reviews the designs and parameters for these magnets, briefly describes features of the magnet designs which respond to the special constraints imposed by the requirements for both accelerator rings, and reviews some of the results of magnet measurements for the prototype. 13 refs., 7 figs., 1 tab.
Date: March 1, 1989
Creator: Tanabe, J.; Avery, R.; Caylor, R.; Green, M.I.; Hoyer, E.; Halbach, K. et al.
System: The UNT Digital Library
Recent results of studies of acceleration of compact toroids (open access)

Recent results of studies of acceleration of compact toroids

The observed gross stability and self-contained structure of compact toroids (CT's) give rise to the possibility, unique among magnetically confined plasmas, of translating CT's from their point of origin over distances many times their own length. This feature has led us to consider magnetic acceleration of CT's to directed kinetic energies much greater than their stored magnetic and thermal energies. A CT accelerator falls in the very broad gap between traditional particle accelerators at one extreme, which are limited in the number of particles per bunch by electrostatic repulsive forces, and mass accelerators such as rail guns at the other extreme, which accelerate many particles but are forced by the stress limitations of solids to far smaller accelerations. A typical CT has about a Coulomb of particles, weighs 10 micrograms and can be accelerated by magnetic forces of several tons, leading to an acceleration on the order of 10/sup 11/ gravities.
Date: March 2, 1984
Creator: Hammer, J. H.; Hartman, C. W. & Eddleman, J.
System: The UNT Digital Library
Multicultural Efforts and Affirmative Action in Brazil: Policies Influencing Education in the Americas (open access)

Multicultural Efforts and Affirmative Action in Brazil: Policies Influencing Education in the Americas

This article explores the intercultural movements toward social justice in education in the Americas, most particularly, North America, and how U.S. multicultural movements and policies influence countries like Brazil.
Date: March 2, 2011
Creator: Murakami-Ramalho, Elizabeth & Auxiliadora Lima Dias da Silva, Maria
System: The UNT Digital Library
Welding iridium heat-source capsules for space missions (open access)

Welding iridium heat-source capsules for space missions

A remote computer-controlled welding station was developed to encapsulate radioactive PuO/sub 2/ in iridium. Weld quench cracking caused an interruption in production of capsules for upcoming space missions. Hot crack sensitivity of the DOP-26 iridium alloy was associated with low melting constituents in the grain boundaries. The extent of cracking was reduced but could not be eliminated by changes to the welding operation. An ultrasonic test was developed to detect underbead cracks exceeding a threshold size. Production was continued using the ultrasonic test to reject capsules with detectable cracks.
Date: March 1982
Creator: Kanne, W. R., Jr.
System: The UNT Digital Library
National solar optical materials program plan: an overview (open access)

National solar optical materials program plan: an overview

A coordinated national program is being formulated to adapt and develop optical materials to support a goal of meeting 20% of our national energy needs with solar by the year 2000. The program contains elements covering absorber, reflector, and transmitter materials but no photovoltaic materials. These elements include research on glass and polymer materials for glazing and reflector components, environmental testing, and long-term reliability modeling. Program subelements that support R and D and encourage commercialization of new products are also discussed. An overview of the proposed funding levels is presented.
Date: March 1, 1980
Creator: Masterson, K.D.
System: The UNT Digital Library
Proton decay: 1982 (open access)

Proton decay: 1982

Employing the current world average ..lambda../sub MS/ = 0.160 GeV as input, the minimal Georgi-Glashow SU(5) model predicts sin/sup 2/theta/sub W/(m/sub W/) = 0.214, m/sub b//m/sub tau/ approx. = 2.8 and tau/sub p/ approx. = (0.4 approx. 12) x 10/sup 29/ yr. The first two predictions are in excellent agreement with experiment; but the implied proton lifetime is already somewhat below the present experimental bound. In this status report, uncertainties in tau/sub p/ are described and effects of appendages to the SU(5) model (such as new fermion generations, scalars, supersymmetry, etc.) are examined.
Date: March 4, 1982
Creator: Marciano, William J.
System: The UNT Digital Library
Adherence of Al/sub 2/O/sub 3/ to CoCrAl coatings. [1000-1200/sup 0/C] (open access)

Adherence of Al/sub 2/O/sub 3/ to CoCrAl coatings. [1000-1200/sup 0/C]

Adhesion between surface scale and protective coating is an essential requirement of a material possessing good overall oxidation resistance. Poor adhesion can lead to exfoliation of the oxide in response to thermal cycling, or mechanically applied stresses, resulting in enhanced oxidation rates. Marked improvements in scale/substrate adhesion can be obtained via the formation of protrusions of oxide growing into the substrate. These act to key the protective scale to the surface and are more effective when a uniform distribution of small oxide pegs can be achieved. Thus, the structure of the coating, the type of rare earth addition, and its concentration are all important and this has been examined using EB-PVD CoCrAl coatings containing a variety of elemental additions. These have been subjected to both isothermal and cyclic oxidation in the temperature range 1000 to 1200/sup 0/C. The coating/scale interface and the development of pegs growing into the coating has been examined in detail by dissolving away the underlying metal + coating using a Br-methanol.
Date: March 1, 1980
Creator: Whittle, D.P.; Boone, D.H. & Allam, I.M.
System: The UNT Digital Library
High resolution studies in martensite (open access)

High resolution studies in martensite

Detailed microstructural studies were performed on the lath martensite in steels containing 0.1 and 0.3 wt %-low alloy structural steels by lattice imaging. This method is providing information on the fine substructural details of dislocated martensite.
Date: March 1, 1980
Creator: Sarikaya, M.; Easterling, K. & Thomas, G.
System: The UNT Digital Library