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MSS generic model: a beginning (open access)

MSS generic model: a beginning

To improve communications and understanding in the field of Mass Storage Systems (MSS), the need exists to formalize the definitions and concepts of MSS. This presentation gives MSS definitions followed by the development of a generic model for MSS.
Date: January 1, 1984
Creator: Collins, W. & Miller, S.
System: The UNT Digital Library
RERTR Program fuel testing and demonstration: an update (open access)

RERTR Program fuel testing and demonstration: an update

The irradiation and postirradiation examination of high-density, reduced-enrichment miniplates and full-sized elements are continuing under the RERTR Program. The emphasis is currently being placed on determining uranium-density/fission-density limits for the highest-density silicide fuels. One whole core demonstration is nearing completion in the FNR, and another, using U/sub 3/Si/sub 2/ fuel, is scheduled to begin in the ORR during the next year. This paper will summarize the progress made during the past year.
Date: January 1, 1984
Creator: Snelgrove, J. L.
System: The UNT Digital Library
Ir/PuO/sub 2/ compatibility: transfer of impurities from plutonium dioxide to iridium metal during high temperature aging (open access)

Ir/PuO/sub 2/ compatibility: transfer of impurities from plutonium dioxide to iridium metal during high temperature aging

Plutonium oxide fuel pellets for powering radioisotopic thermoelectric generators for NASA space vehicles are encapsulated in iridium which has been grain-boundary-stabilized with thorium and aluminum. After aging for 6 months at 1310/sup 0/C under vacuum, enhanced grain growth is observed in the near-surface grains of the iridium next to the PuO/sub 2/. Examination of the grain boundaries by AES and SIMS shows a depletion of thorium and aluminum. Iron, chromium, and nickel from the fuel were found to diffuse into the iridium along the grain boundaries. Enhanced grain growth appears to result from thorium depletion in the grain boundaries of the near-surface grains next to the fuel. However, in one instance grain growth was slowed by the formation of thorium oxide by oxygen diffusing up the grain boundaries.
Date: January 1, 1984
Creator: Taylor, D. H.; Christie, W. H. & Pavone, D.
System: The UNT Digital Library
Economics of a conceptual 75 MW Hot Dry Rock geothermal electric power station (open access)

Economics of a conceptual 75 MW Hot Dry Rock geothermal electric power station

Man-made, Hot Dry Rock (HDR) geothermal energy reservoirs have been investigated for over ten years. As early as 1977 a research-sized reservoir was created at a depth of 2.9 km near the Valles Caldera, a dormant volcanic complex in New Mexico, by connecting two wells with hydraulic fractures. Thermal power was generated at rates of up to 5 MW(t) and the reservoir was operated for nearly a year with a thermal drawdown less than 10/sup 0/C. A small 60kW(e) electrical generation unit using a binary cycle (hot geothermal water and a low boiling point organic fluid, R-114) was operated. Interest is now worldwide with field research being conducted at sites near Le Mayet de Montagne, France; Falkenberg and Urach, Federal Republic of Germany; Yakedake, Japan; and Rosemanowes quarry in Cornwall, United Kingdom. To assess the commercial viability of future HDR electrical generating stations, an economic modeling study was conducted for a conceptual 75 MW(e) generating station operating at conditions similar to those prevailing at the New Mexico HDR site. The reservoir required for 75 MW(e), equivalent to 550 MW of thermal energy, uses at least 9 wells drilled to 4.3 km and the temperature of the water produced should average …
Date: January 1, 1984
Creator: Murphy, H. D.; Drake, R. H.; Tester, J. W. & Zyvoloski, G. A.
System: The UNT Digital Library
Application of pathways analyses for site performance prediction for the Gas Centrifuge Enrichment Plant and Oak Ridge Central Waste Disposal Facility (open access)

Application of pathways analyses for site performance prediction for the Gas Centrifuge Enrichment Plant and Oak Ridge Central Waste Disposal Facility

The suitability of the Gas Centrifuge Enrichment Plant and the Oak Ridge Central Waste Disposal Facility for shallow-land burial of low-level radioactive waste is evaluated using pathways analyses. The analyses rely on conservative scenarios to describe the generation and migration of contamination and the potential human exposure to the waste. Conceptual and numerical models are developed using data from comprehensive laboratory and field investigations and are used to simulate the long-term transport of contamination to man. Conservatism is built into the analyses when assumptions concerning future events have to be made or when uncertainties concerning site or waste characteristics exist. Maximum potential doses to man are calculated and compared to the appropriate standards. The sites are found to provide adequate buffer to persons outside the DOE reservations. Conclusions concerning site capacity and site acceptability are drawn. In reaching these conclusions, some consideration is given to the uncertainties and conservatisms involved in the analyses. Analytical methods to quantitatively assess the probability of future events to occur and the sensitivity of the results to data uncertainty may prove useful in relaxing some of the conservatism built into the analyses. The applicability of such methods to pathways analyses is briefly discussed. 18 refs., …
Date: January 1, 1984
Creator: Pin, F.G. & Oblow, E.M.
System: The UNT Digital Library
Sample environments at IPNS: present and future capabilities (open access)

Sample environments at IPNS: present and future capabilities

Argonne's Intense Pulsed Neutron Source, IPNS, was dedicated as a major user-oriented neutron scattering facility two years ago. Most instruments are now equipped to provide for sample environments in the temperature range 1.5 < T < 1300K. A special facility provides T < 1mK, and another provides pressures to 30kbar. Several environmental equipment designs are described that emphasize time-of-flight technique. Methods for achieving time-resolved experiments which take advantage of the IPNS pulsed source characteristics are discussed. 6 references, 7 figures.
Date: February 1, 1984
Creator: Faber, J. Jr.
System: The UNT Digital Library
Mapping subsurface pathways for contaminant migration at a proposed low level waste disposal site using electromagnetic methods (open access)

Mapping subsurface pathways for contaminant migration at a proposed low level waste disposal site using electromagnetic methods

Electromagnetic methods have been used to measure apparent terrain conductivity in the downstream portion of a watershed in which a waste disposal site is proposed. At that site, the pathways for waste migration in ground water are controlled by subsurface channels. The channels are identified using isocurves of measured apparent conductivity. Two upstream channel branches are found to merge into a single downstream channel which constitutes the main drainage path out of the watershed. The identification and mapping of the ground water pathways is an important contribution to the site characterization study and the pathways analysis. The direct applications of terrain conductivity mapping to the planning of the monitoring program, the hydrogeological testing, and the modeling study are demonstrated. 7 references, 4 figures.
Date: January 1, 1984
Creator: Pin, F.G. & Ketelle, R.H.
System: The UNT Digital Library
Estimating and coping with public response to radioactive waste repository siting (open access)

Estimating and coping with public response to radioactive waste repository siting

The siting and construction of a radioactive waste disposal operation is likely to be controversial in the communities being considered, and at the state and national levels as well. Public response can be conceptualized at two levels: individual, and group or organizational. At the individual level, public response is the behavior of people motivated by their attitudes, knowledge, and perceptions of radioactive waste and its hazards and risks. On the group or organizational level, public response is the organized activity of individuals. Organizations provide the ability to pool resources and talents, set up a division of labor, hire experts, develop a skilled leadership, take legal action, and so on. A broad range of organizations is possible: ad hoc, existing community groups with an added purpose, nationally-recognized organizations, or government offices and agencies. Two cases of response to radioactive waste disposal sites illustrate these sources and kinds of response and lead to indicators to estimate the nature and level of response. Finally, drawing from the theoretical discussion of the sources and levels of public response, on the estimation techniques, and on the examples, specific coping strategies are developed. These strategies take different forms, based on the nature and level of response …
Date: February 7, 1984
Creator: Payne, B.A.
System: The UNT Digital Library
Numerical calculation of complex shock reflections in gases (open access)

Numerical calculation of complex shock reflections in gases

We present here computational results using second order Godunov methods for time-dependent Eulerian gas dynamics with a general (convex) equation of state. 5 refs., 5 figs.
Date: June 1, 1984
Creator: Colella, P. & Glaz, H. M.
System: The UNT Digital Library
Possibilities of polarized protons in Sp anti p S and other high energy hadron colliders (open access)

Possibilities of polarized protons in Sp anti p S and other high energy hadron colliders

The requirements for collisions with polarized protons in hadron colliders above 200 GeV are listed and briefly discussed. Particular attention is given to the use of the ''Siberan snake'' to eliminate depolarizing resonances, which occur when the spin precession frequency equals a frequency contained in the spectrum of the field seen by the beam. The Siberian snake is a device which makes the spin precession frequency essentially constant by using spin rotators, which precess the spin by 180/sup 0/ about either the longitudinal or transverse horizontal axis. It is concluded that operation with polarized protons should be possible at all the high energy hadron colliders. (LEW)
Date: January 1, 1984
Creator: Courant, E. D.
System: The UNT Digital Library
Determination of surface oxide compositions on Alloy 600 using Rutherford backscattering (open access)

Determination of surface oxide compositions on Alloy 600 using Rutherford backscattering

The surface composition of oxides formed on Alloy 600 under conditions similar to those in the primary side of PWR heat exchangers has been studied as a function of potential using Rutherford backscattering and proton inelastic scattering. Electropolished samples of Alloy 600 were exposed at several potentials to a solution of 0.18M H/sub 3/BO/sub 3/(2000 ppM B) with 0.28M LiOH (1.4 ppM Li) at 300/sup 0/C for 450 hours. The potentials relative to an internal hydrogen electrode ranged from -.09 to 750 mV. RBS analysis showed little or no oxide formation on samples exposed at 0 mV. Above 0 mV oxide layers formed whose thicknesses increased with potential. In addition the RBS showed a significantly enhanced concentration of aluminum and silicon in oxide. Both the oxygen and the sum of the aluminum and silicon content appeared to maintain a fixed surface concentration independent of the oxide thickness. Boron and lithium concentration were analyzed with proton inelastic scattering. No lithium was found in any sample. The boron concentration was found to follow the thickness of the oxide.
Date: January 1, 1984
Creator: Hanson, A. L.; Isaacs, H. S. & Kraner, H. W.
System: The UNT Digital Library
Interaction of the neutral deuterium flux with a field-reversed configuration (open access)

Interaction of the neutral deuterium flux with a field-reversed configuration

Recycling effects arising from the penetration of cold neutrals into a hot plasma has been known to contribute to confinement properties of tokamaks, mirrors, RFPs, and spheromaks. To data, however, ionization and charge exchange processes associated with the possible influx of neutrals have been neglected in FRC transport models, or their effects have been found negligible for experiments with short lifetimes (< 20 ..mu..s). These processes are also neglected when ascertaining the experimental particle confinement time tau/sub N/. As experimental FRC lifetimes have recently been extended to record values (greater than or equal to 300 ..mu..s), these effects on transport may no longer be negligible. Furthermore, these losses can be enhanced when FRCs translate at axial speeds much greater than the thermal speeds of the neutrals. The purpose of this analysis is to examine the interaction of neutral deuterium with an FRC. The relevant atomic and molecular processes are reviewed. A simple, steady-state, multi-species 1-D (radial) neutral transport model is described and applied to FRC plasma parameters observed earlier. Estimates of the power loss due to these neutrals are made for both stationary and translating plasmas.
Date: January 1, 1984
Creator: Rej, D.J.
System: The UNT Digital Library
Comments on (n, charged particle) reactions at E/sub n/ = 14 MeV (open access)

Comments on (n, charged particle) reactions at E/sub n/ = 14 MeV

The study of charged particles produced by bombarding materials with 14 MeV neutrons is important for the development of fusion reactors and for biomedical applications as well as for the basic understanding of nuclear reactions. Several experimental techniques for investigating these reactions are discussed here. The interpretation of the data requires the consideration of several possible reaction mechanisms including equilibrium and preequilibrium particle emission and, for light nuclei, sequential particle emission, final state interactions, and the effect of resonances. 17 references.
Date: January 1, 1984
Creator: Haight, R. C.
System: The UNT Digital Library
Nonlinear optics: where do we go from here (open access)

Nonlinear optics: where do we go from here

Nonlinear optics deals with induced polarizations which are not proportional to the input fields. This topic includes the spontaneous scattering of light waves by elementary excitations such as sound waves, plasma waves, heat waves, molecular vibrations (the Raman effect), spin waves, and a host of others; such spontaneous scatterings do not rely on the brightness of the probe light source, and therefore many of these topics were understood well before the invention of the laser. The laser did herald a new age, however. Now materials can be exposed to optical intensities exceeding a 10/sup 15/ Watts per square centimeter, with pulse durations ranging from femtoseconds (10/sup -15/ seconds) to several hours. Additionally, the spectral bandwidths of the exciting light can be made exceedingly narrow and exceedingly directional. Some applications of nonlinear optics are briefly discussed.
Date: January 1, 1984
Creator: Fisher, R. A.
System: The UNT Digital Library
Stimulated vuv radiation from HD excited by a picosecond ArF laser (open access)

Stimulated vuv radiation from HD excited by a picosecond ArF laser

Stimulated emission on E,F ..-->.. B, B ..-->.. X, and C ..-->.. X transitions of HD is observed following two-photon excitation in the E,F state with a picosecond ArF* laser. The efficiency of the strongest B ..-->.. X line is approx.1%. Electron collisions are found to play an important role for C ..-->.. X emissions. 12 refs., 1 fig.
Date: January 1, 1984
Creator: Luk, T.S.; Egger, H.; Mueller, W.; Pummer, H. & Rhodes, C.K.
System: The UNT Digital Library
Neutron radiography at the NRAD facility (open access)

Neutron radiography at the NRAD facility

The NRAD facility uses a 150 kW TRIGA reactor as a source of neutrons and is integrated with a hot cell such that highly radioactive specimens can be radiographed without removing them from the hot cell environment. A second beam tube is located in a separate shielded addition to HFEF and permits neutron radiography of irradiated or unirradiated specimens without subjecting them to the alpha-contaminated hot cell environment. Both beams are optimized for neutron radiography of highly radioactive nuclear fuels. Techniques for using these facilities are described. Advantages include: the ability to perform thermal and epithermal neutron radiography on specimens either inside or outside the hot cell, lack of competition for the use of the reactor, versatility of facility design, and the addition of neutron tomography. (LEW)
Date: January 1, 1984
Creator: McClellan, G.C. & Richards, W.J.
System: The UNT Digital Library
Effect of manufacturing errors on field quality of the LBL SSC dipoles (open access)

Effect of manufacturing errors on field quality of the LBL SSC dipoles

A method is developed for determining the field aberrations resulting from specific kinds of manufacturing errors. This method is applied to the 40-mm i.d. dipoles under consideration at LBL, and also to similar ones with 30 and 50 mm i.d. The method is also applied to the CBA and Doubler/Saver magnets and the results compared with the measurements. The results obtained by this method are also compared with those obtained by assigning identical errors to the positions of the edges of all the coil sectors.
Date: January 1, 1984
Creator: Meuser, R.B.
System: The UNT Digital Library
EPICS System: RSX Implementation Issues (open access)

EPICS System: RSX Implementation Issues

This paper presents implementation details of the Experimental Physics Interactive Control System (EPICS). EPICS is used to control accelerated particle beams for high-energy physics experiments at the Fermi National Accelerator Laboratory. The topics discussed are: interprocessor communication, support of beamline terminals and devices, resource management, mapping, various problems, some solutions to the problems, performance measurement, and modifications and extensions to RSX-11M. This paper is the third of three related papers on the EPICS system. The other two cover (1) the system overview and (2) the system structure and user interface.
Date: February 1, 1984
Creator: Lahey, T. E.; Bartlett, J. F.; Bobbitt, J. S.; Kramper, B. J.; MacKinnon, B. A. & West, R. E.
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
Laser diagnostics of materials and chemistry (open access)

Laser diagnostics of materials and chemistry

Several examples are given of the ability of laser-based diagnostic techniques to make noninvasive measurements in hostile environments. Using coherent anti-Stokes Raman scattering both majority and minority species concentrations, as well as temperature, have been measured in the hot, high-pressure, particle-laden stream of a coal gasifier. In addition, numerous toxic and corrosive elements in the gasifier stream have been identified, but not yet quantified. In addition to providing the capability for making analytical determinations, laser techniques have been extensively employed to measure the rates of elementary chemical reactions. Recently, the temperature regime over which such meaurements are possible has been expanded. Although much of the laser diagnostic activity to date has involved investigations of the gas phase, significant information concerning heterogeneous phenomena can still be inferred. For instance, gas-solid reactions can manifest themselves as changes in vapor phase composition. Furthermore, in the future we expect expanded studies involving reactions of refractory metals (both atoms and clusters) and additional investigations of processes occurring at interfaces and on surfaces.
Date: January 1, 1984
Creator: Hartford, A. Jr.
System: The UNT Digital Library
Partially coherent x-rays from modern storage rings (open access)

Partially coherent x-rays from modern storage rings

Several routes to the development of ideal soft x-ray sources are now being actively pursued. These include atomic lasers, free electron lasers (FELs), and storage ring (synchrotron) undulators. For short wavelength (XUV) applications, FELs and undulators are very closely related, each being dependent on the development of well controlled (low ''emittance'') electron storage rings, with energies of order 0.5 to 1.5 GeV beam energy, and many period magnetic structures, referred to as undulators. The major thrust of this article is that undulators provide the only sure route to coherent soft x-rays in the near term, that they are tuneable throughout the region of interest, and that they will serve a multitude of users, in disparate fields of science and technology, albeit at a large central research facility. 4 refs., 4 figs.
Date: November 1, 1984
Creator: Attwood, D.; Halbach, K. & Kim, K. J.
System: The UNT Digital Library
High-speed simulation of transients in nuclear power plants (open access)

High-speed simulation of transients in nuclear power plants

A combination of advanced modeling techniques and modern, special-purpose peripheral minicomputer technology is presented which affords realistic predictions of plant transient and severe off-normal events in LWR power plants through on-line simulations at a speed ten times greater than actual process speeds. Results are shown for a BWR plant simulation. Results are shown to demonstrate computing capacity, accuracy, and speed. Simulation speeds have been achieved which are 110 times larger than those of a CDC-7600 mainframe computer or ten times greater than real-time speed.
Date: January 1, 1984
Creator: Wulff, W.; Cheng, H.S.; Lekach, S.V. & Mallen, A.N.
System: The UNT Digital Library
Electron impact ionization of N/sup 4 +/ and N/sup 5 +/ (open access)

Electron impact ionization of N/sup 4 +/ and N/sup 5 +/

A new crossed beams apparatus for measuring absolute electron impact ionization cross-sections of multiply charged ions is described. First measurements are also reported which deal with N/sup 4 +/ and N/sup 5 +/. The results are in good agreements with those previously obtained by the Oak Ridge group. For N/sup 5 +/ a non negligible signal is observed below the ground state ionization threshold. It is attributed to the presence of ions in metastable states. From the semi-empirical Lotz formula, the population of ions in those states is estimated to some 3%. 8 refs., 3 figs.
Date: January 1, 1984
Creator: Defrance, P.; Chantrenne, S.; Brouillard, F.; Rachafi, S.; Belic, D.; Jureta, J. et al.
System: The UNT Digital Library
Alpha particle analysis using PEARLS spectrometry (open access)

Alpha particle analysis using PEARLS spectrometry

Alpha particle assay by conventional plate-counting methods is difficult because chemical separation, tracer techniques, and/or self-absorption losses in the final sample may cause either non-reproducible results or create unacceptable errors. PEARLS (Photon-Electron Rejecting Alpha Liquid Scintillation) Spectrometry is an attractive alternative since radionuclides may be extracted into a scintillator in which there would be no self-absorption or geometry problems and in which up to 100% chemical recovery and counting efficiency is possible. Sample preparation may include extraction of the alpha emitter of interest by a specific organic-phase-soluble compound directly into the liquid scintillator. Detection electronics use energy and pulse-shape discrimination to provide discrete alpha spectra and virtual absence of beta and gamma backgrounds. Backgrounds on the order of 0.01 cpm are readily achievable. Accuracy and reproducibility are typically in the 100 +-1% range. Specific procedures have been developed for gross alpha, uranium, plutonium, thorium, and polonium assay. This paper will review liquid scintillation alpha counting methods and reference some of the specific applications. 8 refs., 1 fig.
Date: 1984~
Creator: McKlveen, J. W.; Klingler, G. W.; McDowell, W. J. & Case, G. N.
System: The UNT Digital Library