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Rigid muffin-tin approximation for the electron-phonon interaction in transition metals

Description: Progress in calculating the electron-phonon parameters of transition metals has been based on either the rigid muffin-tin approximation (RMTA) or the fitted modified tight-binding approximation (FMTBA). The RMTA has been shown to be remarkably accurate for average electron-phonon properties, but there are indications that RMTA matrix elements may be too small at low momentum transfer. An attempt is made to demonstrate these assertions concerning the accuracy of RMTA and the numerous electron-ph… more
Date: January 1, 1980
Creator: Butler, W. H.
Partner: UNT Libraries Government Documents Department
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Nuclear safety guide TID-7016 Revision 2

Description: The present revision of TID-7016 Nuclear Safety Guide is discussed. This Guide differs significantly from its predecessor in that the latter was intentionally conservative in its recommendations. Firmly based on experimental evidence of criticality, the original Guide and the first revision were considered to be of most value to organizations whose activities with fissionable materials were not extensive and, secondarily, that it would serve as a point of departure for members of established nu… more
Date: January 1, 1980
Creator: Thomas, J T
Partner: UNT Libraries Government Documents Department
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Assessment of light water reactor fuel damage during a reactivity initiated accident

Description: This paper presents an assessment of LWR fuel damage during a reactivity initiated accident and comments on the adequacy of the present USNRC design requirements. Results from early SPERT tests are reviewed and compared with results from recent computer simulations and PBF tests. A progression of fuel rod and cladding damage events is presented. High strain rate deformation of relatively cool irradiated cladding early in the transient may result in fracture at a radial average peak fuel enthalp… more
Date: January 1, 1980
Creator: MacDonald, P. E.; Seiffert, S. L.; Martinson, Z. R.; McCardell, R. K.; Owen, D. E. & Fukuda, S. K.
Partner: UNT Libraries Government Documents Department
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INSPECT: a package of computer programs for planning and evaluating safeguards inspections

Description: As part of the US Program of Technical Assistance to IAEA Safeguards, PNL has developed a package of computer programs, called INSPECT, that can be used in planning and evaluating safeguards inspections of various types of nuclear facilities. The programs are based on the statistical methods described in Part F of the IAEA Safeguards Technical Manual and can be used to calculate the variance components of the MUF (Material Unaccounted For) statistic, the variance components of the D (difference… more
Date: January 1, 1980
Creator: Mullen, M.F.
Partner: UNT Libraries Government Documents Department
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Bag model, the hyperspherical formalism and the heavy baryons

Description: The bag model framework is used to discuss the heavy baryons, triple flavored objects like ccc, cbb, etc. A nonrelativistic picture seems justified. It is insisted that the long-range interaction consist of a genuine three-body force. Once the potential energy of the three quarks is determined, the three-body Schroedinger equation is solved by the method of hyperspherical expansion. 1 table. (RWR)
Date: January 1, 1980
Creator: Richard, J. M.
Partner: UNT Libraries Government Documents Department
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Low-Cost Solar Array Project. Progress report 14, August 1979-December 1979 and proceedings of the 14th Project Integration Meeting

Description: Progress made by the Low-Cost Solar Array Project during the period August through November 1979, is described. Progress on project analysis and integration; technology development in silicon material, large-area sheet silicon, and encapsulation; production process and equipment development; engineering, and operations, and the steps taken to integrate these efforts are detailed. A report on the Project Integration Meeting held December 5-6, 1979, including copies of the visual materials used, … more
Date: January 1, 1980
Partner: UNT Libraries Government Documents Department
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Low cost Czochralski crystal growing technology: near term implementation of the flat plate photovoltaic cost reduction of the Low Cost Solar Array Project. Fifth quarterly progress report, April 1-June 30, 1980

Description: During this reporting period, the primary activity has been to develop microprocessor control of the crystal growth process and to develop and demonstrate the accelerated crystal growth program. Accelerated recharging of the quartz crucible by the RF melting of polycrystalline silicon feed rods was deemphasized by JPL primarily due to the unavailability of suitable quality feed rods at an effective economical price. The development of the cold crucible program as an alternative method of crucib… more
Date: January 1, 1980
Creator: Roberts, E. G.
Partner: UNT Libraries Government Documents Department
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Relativistic effects in the atomic and nuclear few-body problems

Description: Relativistic effects in the atomic and nuclear few-body systems are classified and discussed with the emphasis on electromagnetic transitions. The size of relativistic corrections, calculational techniques and ambiguities, and comparison of theory and experiment are considered. 8 figures.
Date: January 1, 1980
Creator: Friar, J.L.
Partner: UNT Libraries Government Documents Department
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Western Gas Sands Project. Status report, 1 May-31 May, 1980

Description: This report summarizes the progress of the government-sponsored project directed towards increasing gas production from the low permeability gas sands of the western United States. The planning activities for the multi-well experiment continued in May. Bartlesville Energy Technology Center continued formation evaluation and reservoir simulation studies. Lawrence Livermore Laboratory continued calculations of fracturing near interfaces. Los Alamos Scientific Laboratory focused work on the perman… more
Date: January 1, 1980
Partner: UNT Libraries Government Documents Department
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De-entrainment on vertical elements in air droplet cross flow. [PWR]

Description: De-entrainment phenomena on vertical elements in air-water droplet cross flow are generated using a horizontal array of water spray nozzles and a draft-induced wind tunnel. These conditions are used to obtain experimental values of the de-entrainment efficiency of isolated elements (25.4-, 63.5-, and 101.6-mm-diam cylinders and a 76.2-mm-square tube), and of an array of 101.6-mm-diam cylinders. A flow model is developed that extrapolates the de-entrainment efficiency of isolated elements throug… more
Date: January 1, 1980
Creator: Dallman, J.C. & Kirchner, W.L.
Partner: UNT Libraries Government Documents Department
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Catalyst and process development for hydrogen preparation from future fuel cell feedstocks. Quarterly progress report, October 1, 1979-December 31, 1979. [Pt/Rh, Ni/Rh, Ni/Pt/Rh, Ni, Ni/Ru, Ni/Pt, Ni/Co]

Description: Twelve steam reforming catalysts were evaluated using an autothermal reforming screening unit. Duplicate tests were run with two samples to determine test variability. The samples tested contained either base metals, precious metals, or combinations of base and precious metals. The test was capable of distinguishing among samples where gross variations in composition are the main factor; for example, catalysts containing 2% by weight precious metals are more active than catalysts containing 15%… more
Date: January 1, 1980
Creator: Yarrington, R M; Feins, I R; Hwang, H S & Mayer, C P
Partner: UNT Libraries Government Documents Department
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Numerical study of the NOL large-scale gap test

Description: The NOL large-scale gap test has been modeled numerically using the LASL reactive hydrodynamics code 2DE with Forest Fire burn rates. The model gives good agreement between calculated and experimental critical gap values for VTQ-2 and Composition B. The calibration of peak pressure in the gap versus gap length has been obtained from these calculations, and is in good agreement with the published experimental curve. The two-dimensional nature of the gap test is evident from the curvature of the … more
Date: January 1, 1980
Creator: Bowman, A.L.
Partner: UNT Libraries Government Documents Department
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Surprising patterns of CMOS susceptibility to ESD and implications on long-term reliability

Description: CMOS electrostatic discharge (ESD) failures in a product where, by design, the device input terminals are not accessible to ESD led to this study of device susceptibility and an analysis of the long-term reliability of devices in assemblies from that production line. Some surprising patterns of device susceptibility are established and it is shown that the probability of long-term failure in devices whose electrical characteristics have been degraded by electrostatic discharge is small.
Date: January 1, 1980
Creator: Schwank, J.R.; Baker, R.P. & Armendariz, M.G.
Partner: UNT Libraries Government Documents Department
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Validation and sensitivity of a simulated photograph technique for visibility modeling

Description: The Los Alamos Scientific Laboratory (LASL) visibility model is capable of producing simulated before and after pictures that illustrate visual effects of smoke plumes. Although the model has been under development for a few years, until recently there had been very little testing of the model against field experience or testing of sensitivity of the model results to numerical approximations used in the model. Further validation and sensitivity testing of the LASL model began in late 1979. The … more
Date: January 1, 1980
Creator: Williams, M.; Chan, L.Y. & Lewis, R.
Partner: UNT Libraries Government Documents Department
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Electronic band structure and optical properties of the cubic, Sc, Y and La hydride systems

Description: Electronic band structure calculations are used to interpret the optical spectra of the cubic Sc, Y and La hydride systems. Self-consistent band calculations of ScH/sub 2/ and YH/sub 2/ were carried out. The respective joint densities of states are computed and compared to the dielectric functions determined from the optical measurements. Additional calculations were performed in which the Fermi level or band gap energies are rigidly shifted by a small energy increment. These calculations are t… more
Date: January 1, 1980
Creator: Peterman, D. J.
Partner: UNT Libraries Government Documents Department
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The (t,d) reaction on the Ni isotopes with polarized tritons

Description: The (t vector,d) reaction has been measured on targets of /sup 58/ /sup 60/ /sup 62/ /sup 64/Ni with 17 MeV polarized tritons. Spectroscopic factors, angular momentum and total spin transfer were obtained from the differential cross section and A/sub y/ values of levels up to 3.5 MeV in excitation energy. The present (t,d) measurement enables a better description of the 9/2/sup +/ and 5/2/sup +/ states which show significant shell crossing effects as a function of increasing neutron number.
Date: January 1, 1980
Creator: Flynn, E. R.; Cizewski, J. A.; Brown, R. E.; Hardekopf, R. A. & Sunier, J. W.
Partner: UNT Libraries Government Documents Department
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Vacuum ultraviolet electronic properties of liquids. Annual progress report, 1 November 1979-31 October 1980

Description: Areas covered are: optical and dielectric properties of hexamethyl-phosphoric triamide; photoemission from uv irradiated liquids; photon and photoelectron mean free paths in liquids; properties of Kapton films; and uv transmission of polycyclic organic molecules. (GHT)
Date: January 1, 1980
Creator: Painter, L.R.
Partner: UNT Libraries Government Documents Department
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Stochastic model of radioiodine transport

Description: A research project has been underway at the Oak Ridge National Laboratory with the objective to evaluate dose assessment models and to determine the uncertainty associated with the model predictions. This has resulted in the application of methods to propagate uncertainties through models. Some techniques and results related to this problem are discussed.
Date: January 1, 1980
Creator: Schwarz, G. & Hoffman, F.O.
Partner: UNT Libraries Government Documents Department
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Kaon-nucleus interactions

Description: The recent progress in hypernuclear physics, in particular the studies of ..lambda.. and ..sigma.. states via the strangeness-exchange (K/sup -/,..pi../sup -/) reaction, are reviewed. Prospects for future investigations with (proposed) intense kaon beams are also evaluated, for instance the production of high spin hypernuclei via the (..pi../sup +/,K/sup +/) reaction, and the formation of strangeness S = -2 hypernuclei (..lambda lambda.. or Xi/sup -/) by means of the (K/sup -/,K/sup +/) process… more
Date: January 1, 1980
Creator: Dover, C B
Partner: UNT Libraries Government Documents Department
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Testing program for determining the mechanical properties of concrete to temperatures of 621/sup 0/C

Description: Concrete temperatures in a Liquid Metal Fast Breeder Reactor (LMFBR) in excess of normal code limits can result from postulated large sodium spills in equipment cells. Elevated temperature concrete property data which may have application for providing a basis for the design and evaluation of such postulated accident conditions is limited. Data thus needed to be developed commensurate with LMFBR plant applications for critical physical and mechanical concrete properties under prototypic thermal… more
Date: January 1, 1980
Creator: Oland, C.B.; Naus, D.J. & Robinson, G.C.
Partner: UNT Libraries Government Documents Department
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Survey of helium in soil gases of Long Valley, Califorina

Description: Soil and water samples in and around the Long Valley geothermal area, Mono County, California, were collected and analyzed for helium by means of a modified mass spectrometer leak detector to see what relationship helium concentrations might have to geothermal features of the area, and to previously studied mercury anomalies in the area. Anomalously high concentrations of helium occurred over part of a major Sierra Nevada frontal fault and over other faults outside of the caldera. Anomalously l… more
Date: January 1, 1980
Creator: Hinkle, M. E. & Kilburn, J. E.
Partner: UNT Libraries Government Documents Department
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Neutron environment in d + Li facilities

Description: A microscopic d + Li neutron yield model has been developed based upon classical models and experimental data. Using equations suggested by the Serber and evaporation models, a generalized least squares adjustment procedure generated angular yields for E/sub d/ to 40 MeV using the available experimental data. The HEDL-UCD experiment at E/sub d/ = 35 was used to adjust parameters describing the neutron spectra. The model is used to predict yields, spectra, and damage responses in the FMIT Test C… more
Date: January 1, 1980
Creator: Mann, F. M.; Schmittroth, F. & Carter, L. L.
Partner: UNT Libraries Government Documents Department
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