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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.
Item Type: Refine your search to only Article
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
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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.
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Partner: UNT Libraries Government Documents Department
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Recovery of deformed and hydrogen-charge palladium

Description: Positron lifetime and Doppler-broadening studies made at 300 K have been used to investigate the interaction between interstitial hydrogen and lattice defects in deformed Pd. Specimens were charged with hydrogen at 300 K to levels up to 0.1%. The presence of hydrogen was found to have no effect on the recovery curves of Pd upon annealing to 400/sup 0/C. By 400/sup 0/C the values for both lifetime and Doppler-broadening for both cold worked and cold worked plus hydrogen were below the values obt… more
Date: January 1, 1982
Creator: Snead, C. L. Jr.; Lynn, K. G. & Lynch, J. F.
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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.
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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.
Item Type: Refine your search to only Article
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
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Excitation of giant resonances via direct reactions

Description: Experimental measurements of electric giant multipole resonances are discussed. The parameters of the giant quadrupole resonance are now firmly established by an extensive set of measurements. The GQR is providing a significant influence in other areas of nuclear physics. The monopole resonance has now been established and its observation has provided the first direct measure of the nuclear compressibility. A strong case for the existence of a giant octupole resonance is now being made through … more
Date: January 1, 1982
Creator: Bertrand, F.E.
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Partner: UNT Libraries Government Documents Department
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Picotron 100 streak tubes as a 150-channel photometer

Description: The characterization of a streak camera based upon Picotron 100 tube types is given. Both a large (30 cm 1 x 10 cm dia.) and a small (18 cm 1 x 5 cm dia.) version of this design has been tested. Over 150 channels of information are simultaneously time resolved with system S.N.R. of 3 at 100 picosecond time resolution without post intensification. Absolute photometric evaluation is given in the dynamic mode, i.e. while operating in the picosecond time domain. Such quantitative data has been lack… more
Date: January 1, 1982
Creator: Majumdar, S.; Weiss, P.B. & Black, J.P.
Item Type: Refine your search to only Article
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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impulsive ion acceleration in earth's outer magnetosphere

Description: Considerable observational evidence is found that ions are accelerated to high energies in the outer magnetosphere during geomagnetic disturbances. The acceleration often appears to be quite impulsive causing temporally brief (10's of seconds), very intense bursts of ions in the distant plasma sheet as well as in the near-tail region. These ion bursts extend in energy from 10's of keV to over 1 MeV and are closely associated with substorm expansive phase onsets. Although the very energetic ions… more
Date: January 1, 1985
Creator: Baker, D.N. & Belian, R.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantitative analysis of the hydrothermal system in Lassen Volcanic National Park and Lassen Known Geothermal Resource Area

Description: The Lassen hydrothermal system is in the southern Cascade Range, approximately 70 kilometers east-southeast of Redding, California. The conceptual model of the Lassen system is termed a liquid-dominated hydrothermal system with a parasitic vapor-dominated zone. The essential feature of this model is that steam and steam-heated discharge at relatively high elevations in Lassen Volcanic National Park (LVNP) and liquid discharge with high chloride concentrations at relatively low elevations outsid… more
Date: January 1, 1984
Creator: Sorey, M.L. & Ingebritsen, S.E.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Article
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
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microcrystalline silicon growth for heterojunction solar cells. Second quarterly report, 1 April 1983-30 June 1983

Description: In this reporting period, a single source of evaporation with B mixed with highly doped Si was used instead of the co-evaporation of separate Si and B sources. The purpose was to reduce possible carbon contamination. The results of both the heterojunction or heteroface structures, however, were similar to last quarter when evaporation was used. The best Voc of the heterojunction was about 460mV and no improvement in Voc in the heteroface structure, was observed; slight Voc degradation occurred.… more
Date: January 1, 1983
Creator: Iles, P. A.; Leung, D. C. & Fang, P. H.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Article
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
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Laser-plasma interaction experiments at laser wavelengths of 1. 064. mu. m, 0. 532. mu. m, and 0. 355. mu. m

Description: The effect of laser wavelength on laser-plasma coupling is one of the critical issues facing the laser driven inertial confinement community. The advantages of using lasers with output wavelength less than 1 ..mu..m, such as enhanced absorption and hydrodynamic efficiency, reduction in parametric instabilities and corresponding suprathermal electron generation, have long been predicted theoretically.
Date: January 1, 1982
Creator: Campbell, E. M.; Mead, W. C. & Turner, R. E.
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Partner: UNT Libraries Government Documents Department
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Growth regulation by macrophages

Description: The evidence reviewed here indicates that macrophages, either acting alone or in concert with other cells, influence the proliferation of multiple types of cells. Most of the data indicate that these effects are mediated by soluble macrophage-elaborated products (probably proteins) although the role of direct cell-to-cell contacts cannot be ruled out in all cases. A degree of success has been achieved on the biochemical characterization of these factors, due mainly to their low specific activit… more
Date: January 1, 1982
Creator: Wharton, W.; Walker, E. & Stewart, C.C.
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Partner: UNT Libraries Government Documents Department
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Diskless LSI-11 systems

Description: Programs for dedicated LSI-11 based systems can easily be stored in ROM instead of floppy disks, yet execute the same as disk-stored programs. Two sample systems are described.
Date: January 1, 1982
Creator: Ford, W. & Shirk, D. G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Severe accident core heatup transients in modular high temperature gas-cooled reactors without operating Reactor Cavity Cooling Systems

Description: The ultimate decay heat removal system for the current Modular High Temperature Gas-Cooled reactors is a completely passive natural convection air cooling loop. This paper considers an extremely remote accident scenario, where even this passive system fails, and heat rejection is only via a layer of thermal insulation to the reactor silo structure and the surrounding soil. The results show that even in this case the peak fuel temperatures remain well within safe limits. However, vessel and conc… more
Date: January 1, 1988
Creator: Kroeger, P. G.
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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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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