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Adaptive Mesh Refinement for 1-Dimensional Gas Dynamics

Description: We consider the solution of the one-dimensional equation of gas-dynamics. Accurate numerical solutions are difficult to obtain on a given spatial mesh because of the existence of physical regions where components of the exact solution are either discontinuous or have large gradient changes. Numerical methods treat these phenomena in a variety of ways. In this paper, the method of adaptive mesh refinement is used. A thorough description of this method for general hyperbolic systems is given else… more
Date: 1982-08~
Creator: Hedstrom, Gerald; Rodrigue, Garry; Berger, Marsha & Oliger, Joseph
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Acoustic agglomeration of power plant fly ash. Final report

Description: The work has shown that acoustic agglomeration at practical acoustic intensities and frequencies is technically and most likely economically viable. The following studies were performed with the listed results: The physics of acoustic agglomeration is complex particularly at the needed high acoustic intensities in the range of 150 to 160 dB and frequencies in the 2500 Hz range. The analytical model which we developed, although not including nonlinear acoustic efforts, agreed with the trends obs… more
Date: January 1, 1982
Creator: Reethof, G. & McDaniel, O.H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aspects of model selection in multivariate analyses

Description: Analysis of data sets that involve large numbers of variables usually entails some type of model fitting and data reduction. In regression problems, a fitted model that is obtained by a selection process can be difficult to evaluate because of optimism induced by the choice mechanism. Problems in areas such as discriminant analysis, calibration, and the like often lead to similar difficulties. The preceeding sections reviewed some of the general ideas behind assessment of regression-type predic… more
Date: January 1, 1982
Creator: Picard, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Fast-neutron total and scattering cross sections of elemental palladium

Description: Neutron total cross sections of palladium are measured from approx. = 0.6 to 4.5 MeV with resolutions of approx. = 30 to 70 keV at intervals of less than or equal to 50 keV. Differential neutron elastic- and inelastic-scattering cross sections are measured from 1.4 to 3.85 MeV at intervals of 50 to 100 keV and at 10 to 20 scattering angles distributed between approx. = 20 and 160/sup 0/. The experimental results are compared with respective quantities given in ENDF/B-V and used to deduce an opt… more
Date: June 1, 1982
Creator: Smith, A. B.; Guenther, P. T. & Whalen, J. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Interaction of noble-metal fission products with pyrolytic silicon carbide

Description: Fuel particles for the High-Temperature Gas-Cooled Reactor (HTGR) contain layers of pyrolytic carbon and silicon carbide, which act as a miniature pressure vessel and form the primary fission product barrier. Of the many fission products formed during irradiation, the noble metals are of particular interest because they interact significantly with the SiC layer and their concentrations are somewhat higher in the low-enriched uranium fuels currently under consideration. To study fission product-… more
Date: January 1, 1982
Creator: Lauf, R. J. & Braski, D. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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High-temperature turbine technology program hot-gas path development test. Part II. Testing

Description: This topical report of the US Department of Energy High-Temperature Turbine Technology (DOE-HTTT) Phase II program presents the results of testing full-scale water-cooled first-stage and second-stage turbine nozzles at design temperature and pressure to verify that the designs are adequate for operation in a full-scale turbine environment. Low-cycle fatigue life of the nozzles was demonstrated by subjecting cascade assemblies to several hundred simulated startup/shutdown turbine cycles. This te… more
Date: March 1, 1982
Creator: Horner, M. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Internal magnetic fields in hcp-iron

Description: The magnetic behavior of hcp-Fe (epsilon iron) has been investigated by the Moessbauer Effect over a wide range of temperature T, pressure P, and applied magnetic field H/sub 0/. The internal field H/sub i/ of the induced moment is given by H/sub i/ = 0.20 +- .01 H/sub 0/ and is independent of T and P. Enhanced paramagnetism is suggested as the most likely origin for a contribution of this magnitude to H/sub i/.
Date: January 1, 1982
Creator: Taylor, R. D.; Cort, G. & Willis, J. O.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Integrity of PWR pressure vessels during overcooling accidents

Description: The reactor pressure vessel in a pressurized water reactor is normally subjected to temperatures and pressures that preclude propagation of sharp, crack-like defects that might exist in the wall of the vessel. However, there is a class of postulated accidents, referred to as overcooling accidents, that can subject the pressure vessel to severe thermal shock while the pressure is substantial. As a result of such accidents vessels containing high concentrations of copper and nickel, which enhance… more
Date: January 1, 1982
Creator: Cheverton, R.D.; Iskander, S.K. & Whitman, G.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Light composite fermions: an overview

Description: Some rules which have been proposed, including 't Hooft's anomaly conditions, decoupling conditions and tumbling versus no tumbling are discussed. Then mass generation mechanisms for composite fermions are covered, including weak gauging, strong gauging, and unification. The origin of the different generations of quarks and leptons is then considered. In the context of composite models, the three generations of quarks and leptons must appear in the first approximation as three sets of massless … more
Date: January 1, 1982
Creator: Raby, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Clonal theory of radiation carcinogenesis

Description: In some cases, usually involving high-LET radiations, the dose response at low doses follows a power function of dose with exponent less than one over a wide dose range. This type of response is of great interest since (a) it implies greater effect per unit dose at progressively smaller doses, and (b) it is not predicted by most models and theories of radiobiology. A theoretical framework is presented for responses having the above characteristics over a dose range extending over a factor of 10… more
Date: January 1, 1982
Creator: Baum, J.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Microfaunal evidence of age and depositional environments of the Cerro Prieto section (Plio-Pleistocene), Baja California, Mexico

Description: Microfossils including benthic and planktic foraminifera, ostracodes, calcareous algae, fish skeletal material, and fragments of pelecypods were found in 14 core samples from depths of 185 to 1952 m in the Cerro Prieto geothermal field, providing evidence of both the age and depositional history of sediments comprising the 3000-m-thick Pliocene and Pleistocene section in this area. Ostracodes of brackish water and marine origin constitute the most common microfossils present in this sequence oc… more
Date: January 1, 1982
Creator: Ingle, J.C. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Statistical fluctuations in heavy-ion collisions

Description: The relevance of the statistical equilibrium limit to the description of substantially relaxed degrees of freedom is discussed. Fluctuations are considered specifically in the following processes: the correlation between entrance-channel angular momentum and exit-channel kinetic energy; the sharing of the dissipated kinetic energy between the two fragments; the magnitude and the alignment of the fragment angular momentum including the effect of shell structure. It is found that statistical fluc… more
Date: February 1, 1982
Creator: Moretto, Luciano G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Electron bremsstrahlung angular-distribution fits for atomic numbers 1 less than or equal to Z less than or equal to 92, and incident-electron energies 1 keV less than or equal to T less than or equal to 500 keV

Description: The analytic fit of a simple expression to the electron bremsstrahlung angular distribution cross section d/sup 2/sigma/dkd..cap omega.. (differential in the emitted photon energy k and angle ..cap omega..) is investigated. Optimal choices for the fit parameters are determined and fit coefficients are tabulated for a large number of neutral-atom cases. Results are also presented for fits to the relativistic Coulomb-Born approximation. Comparisons between the screened neutral-atom results and th… more
Date: January 1, 1982
Creator: Kissel, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Design considerations for a steam-injection pilot with in-situ foaming

Description: This report reviews the necessary aspects of the planning, operation, evaluation, environmental impact and cost to implement a field pilot of steam injection with in-situ foaming. The Stanford University Petroleum Research Institute (SUPRI) is planning to implement such a pilot in Kern County, California. The cost of the pilot will be shared by the US Department of Energy and an oil company. Some important aspects of drilling and completion programs and their specifications, permits from regula… more
Date: August 1, 1982
Creator: Siddiqui, M.H.; Sanyal, S.K. & Horn, A.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Report of the Working Group on Media Accelerators

Description: A summary is given of the activities of those in the Media Accelerator Group. Attention was focused on the Inverse Cherenkov Accelerator, the Laser Focus Accelerator, and the Beat Wave Accelerator. For each of these the ultimate capability of the concept was examined as well as the next series of experiments which needs to be performed in order to advance the concept.
Date: April 12, 1982
Creator: Sessler, Andrew M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Shear alfven resonances in Tokapole II

Description: It has been suggested that efficient heating can occur by coupling energy through the shear Alfven resonance that is predicted to occur at particular locations within inhomogeneous plasmas. This heating mechanism should be applicable to tokamaks; however, the existence of the resonances in tokamaks has not yet been established experimentally. We present here direct observations of localized enhancement in the driven wave magnetic field which are compatible with theoretical predictions for the s… more
Date: March 1, 1982
Creator: Witherspoon, F.D.; Prager, S.C. & Sprott, J.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of impurities in the Tandem Mirror Experiment using extreme-ultraviolet spectroscopy

Description: Impurities in the Tandem Mirror Experiment (TMX) have been studied using extreme ultraviolet spectroscopy. Three time-resolving absolutely-calibrated normal-incidence monochromators, one on each section of TMX, were used to study the impurity emissions in the wavelength range of 300 A to 1600 A. The instruments on the east end cell and central cell were each capable of obtaining spatially-resolved profiles from 22 chords of the plasma simultaneously while the instrument on the west end cell mon… more
Date: May 12, 1982
Creator: Strand, O. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Recent US target-physics-related research in heavy-ion inertial fusion: simulations for tamped targets and for disk experiments in accelerator test facilities

Description: Within the last few years, there have also appeared in the Heavy-Ion Fusion literature several studies of targets which have outer tampers. One-dimensional simulations indicate higher target gains with a judicious amount of tamping. But for these targets, a full investigation has not been carried through in regards to conservative criteria for fluid instabilities as well as reasonable imperfections in target fabrication and illumination symmetry which all affect target ignition and burn. Compar… more
Date: June 24, 1982
Creator: Mark, J.W.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Terrestrial fate of coal-liquid constituents: behavior of alkyl anilines in soil

Description: The low molecular weight aromatic amines (anilines) are important water soluble constituents of coal liquids. The impact of anilines released to the terrestrial environment will largely depend on their mobility and persistence. Studies were conducted to investigate those processes governing the mobility and persistence of the alkylanilines, namely, soil sorption and chemical/microbial degradation. Soil sorption measurements were conducted on aniline and several methyl substituted anilines on A … more
Date: July 1, 1982
Creator: Felice, L. J.; Zachara, J. M. & Rogers, J. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Use of ICRH for startup and initial heating of the TMX-U central cell

Description: Ion cyclotron resonance heating (ICRH) was evaluated and it was found to be satisfactory for use in establishing the conditions necessary to form a thermal barrier in TMX-upgrade (TMX-U). We discuss the constraints that must be satisfied in order to maintain a plasma, and outline a complete startup scenario that ends with the plasma at design parameters. The detailed discussions in this report concentrate on those parts of startup where ICRH is necessary. The ability of ICRH to couple power int… more
Date: May 1, 1982
Creator: Molvik, A.W. & Falabella, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Shielding considerations for advanced space nuclear reactor systems

Description: To meet the anticipated future space power needs, the Los Alamos National Laboratory is developing components for a compact, 100 kW/sub e/-class heat pipe nuclear reactor. The reactor uses uranium dioxide (UO/sub 2/) as its fuel, and is designed to operate around 1500 k. Heat pipes are used to remove thermal energy from the core without the use of pumps or compressors. The reactor heat pipes transfer mal energy to thermoelectric conversion elements that are advanced versions of the converters u… more
Date: January 1, 1982
Creator: Angelo, J.P. Jr. & Buden, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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