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Evaluation of an all-glass, evacuated, tubular, nonfocusing, nontracking solar collector array. First annual progress report, July 1, 1976--August 31, 1977

Description: A spaced, evacuated tubular radiation receiver employing a highly selective absorber surface and light enhancement features has been subject to extensive test and analysis. Air was used as the heat transfer fluid. The design, installation, test and analysis of the air cooled collector was conducted. The thermal performance of the air cooled collector was found to be better than predicted when rated on an all day operating basis. The high performance characteristic is enhanced by the features of… more
Date: December 1, 1977
Creator: Moan, K L
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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LLL total flow geothermal program: summary of two-phase nozzle tests for scale control and materials performance

Description: A series of nozzle and wearblade tests to evaluate scale control and materials performance under total flow nozzle inlet conditions and simulated turbine blade environments was completed using Magmamax No. 1 well fluid. Brine acidification was effective in preventing scale in nozzles and on wearblade flow surfaces. Acid consumption measurements indicate that acid cost will be less than 2 mills/100 lb. brine. Measured erosion rates were low and the results indicate that available materials will … more
Date: December 1, 1977
Creator: Tardiff, G.E. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Transient Temperature Distributions in a Thermally Orthotropic Plate With Non-Uniform Surface Heating

Description: ent temperature variation in a thermally orthotropic plate which is subjected to an arbitrary heating rate distribution along one face with all other surfaces being insulated. Dimensionless temperature histories and distributions determined from this solution are presented for the special, but representative, case of a linearly varying heating rate distribution on plates with varying degrees of thermal orthotropy. These results establish quantitatively the value of a material with high planar a… more
Date: June 1, 1961
Creator: Hornbaker, David Ross
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Progress in collisions of multiply charged ions

Description: The increasing power and availability of supercomputers during the last decade led to significant progress in the theory of multicharged ion interactions. However, important tests of many theoretical predictions were lacking, and have become possible only quite recently as new capabilities have been realized in the laboratory. This paper broadly surveys some of these experimental developments, and their impact on our understanding of collisional interactions of multicharged ions. The scope is l… more
Date: January 1, 1991
Creator: Phaneuf, R.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure of NH/sub 3/ on Ni(111)

Description: In a recent study of the adsorption of NH/sub 3/ on NI(111) at T approx. 190 K using angle resolved UPS, it was concluded that NH/sub 3/ is molecularly adsorbed, and is bonded to the surface via the N atom with the H atoms oriented away from the surface. To study the bonding configuration using a direct and independent technique, we have examined NH/sub 3/ on Ni(111) using the electron stimulated desorption ion angular distribution (ESDIAD) method, coupled with temperature programmed desorption… more
Date: January 1, 1980
Creator: Madey, T. E.; Houston, J. E.; Seabury, C. W. & Rhodin, T. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Surface footprint from initial Chernobyl release as indicated by the meso-alpha MLAM (Multi-Layer Air Mass) model

Description: This document reports the results of dose calculations from the Chernobyl reactor accident in April 1986. The calculations were completed in 1987. The results are now being published to disseminate the information to an audience of potential users. This study's objective was to model the transport path of materials released during April 26 and 27, the first 48 hours of the accident. 5 refs., 15 figs.
Date: December 1, 1989
Creator: Davis, W. E.; Olsen, A. R.; Didier, B. T.; Tucker, P. E. & Damschen, D. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Interaction of xenon light with the surface of 304 stainless steel

Description: Laser amplifier frames fabricated from Type 304 stainless steel are known to cause damage to glass lenses by ejecting particles which are deposited on the lenses. High energy pulses of xenon light interact with the steel surface to produce damage sites. Heat treatment and surface cleaning procedures greatly affect the surface stability of the steel and influence contamination generated by the steel. It is believed that inclusions and/or carbides play a role, and the size of damage sites observe… more
Date: February 14, 1978
Creator: Krenzer, R. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface, interface and thin-film magnetism

Description: In the last quarter of the 20th century, with the information revolution and the ever growing need to acquire, store, and retrieve information, the science and technologies attached to magnetic recording have experienced an explosive growth. Central to those pursuits has been the materials science of magnetism as it applies to surfaces, interfaces, and thin films. This report discusses topics on thin-film magnetism such as: theory, physical effects, prospects, opportunities and future developme… more
Date: July 1, 1991
Creator: Falicov, L.M. (Lawrence Berkeley Lab., CA (United States) California Univ., Berkeley, CA (United States). Dept. of Physics)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Generation of H sup minus , H sub 2 (v double prime ), and H atoms by H sub 2 sup + and H sub 3 sup + ions incident upon barium surfaces

Description: The generation of vibrationally excited molecules by electron excitation collisions and the subsequent generation of negative ions by dissociative attachment to these molecules has become a standard model for volume source operation. These processes have been supplemented recently by the demonstration of atom-surface recombination to form vibrationally excited molecules, and enhanced negative ion formation by protons incident upon barium electrodes. In this paper we consider the additional proc… more
Date: January 1, 1989
Creator: Hiskes, J.R. & Karo, A.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Validated heat-transfer and pressure-drop prediction methods based on the discrete element method: Phase 1, Three-dimensiional roughness

Description: A computer program based on the discrete element method has been developed and validated to compute friction factors and Nusselt numbers for fully developed turbulent flow and heat transfer in pipes with three-dimensional roughness elements. Computational results are compared with appropriate cases from heat transfer experiments in the literature. The predictions were in general in very good agreement with the experimental data.
Date: February 1, 1992
Creator: Taylor, R.P. & Hodge, B.K. (Mississippi State Univ., MS (United States). Dept. of Mechanical and Nuclear Engineering)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Surface damage of molybdenum and TZM alloy under D/sup +/ impact

Description: The surface damage of polycrystalline molybdenum and TZM alloy under 40-, 60-, and 120-keV D/sup +/ impact has been investigated for irradiation in both pulsed and continuous mode for total doses varying from 1.7 x 10/sup 17/ to 2.2 x 10/sup 19/ ions/cm/sup 2/ and for target temperatures verying from ambient temperature to 400/sup 0/C. Analysis by scanning electron microscopy of the MO samples held at ambient temperatures during D/sup +/ irradiations in both pulsed and continuous modes revealed… more
Date: January 1, 1977
Creator: Das, S.K.; Kaminsky, M. & Dusza, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Instruction manual for the program SHAPEFACTOR

Description: A numerical technique is presented for evaluating the geometrical radiant exchange factors (also called shape or view factors) between surfaces with interposed obstructions. Since the program is developed for plane surfaces, arbitrary surfaces are expressed by the juxtaposition of plane surfaces; to simplify the input and output, the program respectively combines and decomposes these elemental surfaces. The data input format, although designed for manual input, is ideally suited for standard th… more
Date: October 1, 1980
Creator: Emery, A.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effects of Overpressures in Group Shelters on Animals and Dummies

Description: S>Relative biological hazards of blast were studied in two types of communal air-raid shelters during Shots 1 and 8. Dogs, restrained within the shelters during detonation, were studied pathologically and clinically for blast injuries. Two anthropometric dummies were test objects for displacement studies utilizing high-speed photography. Physical data included pressure vs time and air-drag determinations. During Shot 1, animals sustained marked blast damages (hemorrhages in lungs and abdominal … more
Date: September 1, 1953
Creator: Roberts, J. E.; White, C. S. & Chiffelle, T. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical Vapor Deposition of Refractory Metal Reflectors for Spectrally Selective Solar Absorbers. Annual Report, May 1, 1978-April 30, 1979

Description: Three methods are described to fabricate by chemical vapor deposition (CVD) molybdenum films which rival conventional mirror materials in their infrared reflectance. With an absolute reflectance of 97.4% at 10 ..mu..m, these Super Molybdenum films reflect better than any other molybdenum film previously reported. When deposited in the presence of oxygen, films of a reduced reflectance over the solar emission range result. If passivated and antireflected by a Si/sub 3/N/sub 4/ layer, such Black … more
Date: May 1, 1979
Creator: Seraphin, B. O. & Carver, G. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simulation experiments and solar wind sputtering

Description: In order to isolate the role played by solar wind sputtering from other lunar surface phenomena a number of simulation experiments were performed, including isotope abundance measurements of Ca sputtered from terrestrial fluorite and plagioclase by 50-keV and 130-keV /sup 14/N beams, measurement of the energy distribution of U atoms sputtered with 80-keV /sup 40/Ar, and measurement of the fraction of sputtered U atoms which stick on the surfaces used to collect these atoms. 10 references. (JFP)
Date: January 1, 1978
Creator: Griffith, J. E.; Papanastassiou, D. A.; Russell, W. A.; Tombrello, T. A. & Weller, R. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Research on thermophoretic and inertial aspects of ash particle deposition on heat exchanger surfaces in coal-fired equipment

Description: The overall goal of this research in the area of ash transport was to advance the capability of making reliable engineering predictions of the dynamics and consequences of net deposit growth for surfaces exposed to the products of coal combustion. To accomplish this for a wide variety of combustor types, coal types, and operating conditions, this capability must be based on a quantitative understanding of each of the important mechanisms of mineral matter transport, as well as the nature of the… more
Date: May 1, 1990
Creator: Rosner, D.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Advances in materials science, Metals and Ceramics Division. Triannual progress report, February-May 1980

Description: Research is reported in the magnetic fusion energy and laser fusion energy programs, aluminium-air battery and vehicle research, geothermal research, nuclear waste management, basic energy science, and chemistry and materials science. (FS)
Date: August 1, 1980
Creator: Truhan, J.J. & Gordon, K.M. (eds.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Expected environments in high-level nuclear waste and spent fuel repositories in salt

Description: The purpose of this report is to describe the expected environments associated with high-level waste (HLW) and spent fuel (SF) repositories in salt formations. These environments include the thermal, fluid, pressure, brine chemistry, and radiation fields predicted for the repository conceptual designs. In this study, it is assumed that the repository will be a room and pillar mine in a rock-salt formation, with the disposal horizon located approx. 2000 ft (610 m) below the surface of the earth.… more
Date: August 1, 1980
Creator: Claiborne, H.C. & Rickertsen, L.D., Graham, R.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AIRBLAST OVERPRESSURE AND DYNAMIC PRESSURE OVER VARIOUS SURFACES

Description: Static overpressure and dynamic pressure versus time over surfaces processing different physical properties were measured on two tower shots, 6 and 12. On Shot 12, three surfaces were provided: the natural desert, a water surface consisting of a flooded area, and an asphalt surface. On Shot 6, desert and asphalt areas only were available. There were 123 channels of instrumentation installed for Shot 12, and 24 for Shot 6. From the data, a system of wave-form classification was devised for overp… more
Date: September 11, 1957
Creator: Sachs, D. C.; Swift, L. M. & Sauer, F. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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FUEL ELEMENT DEVELOPMENT PROGRAM FOR THE PEBBLE BED REACTOR. Final Report

Description: >The basic fuel element consisted of a uniform dispersion of fuel in a 1 1/2 inch diameter graphite sphere. Ceramic coatings for the retention of fission products were studied. It was found-that molecularly deposited'' ceramics such as alumina, siliconized silicon carbide, and pyrolytic carbon were excellent barriers to fission product leakage. The most advantageous location for ceramic coatings was found to be on the individual fuel particles, where the coating was subject to smaller forces an… more
Date: April 30, 1961
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A PULSED EDDY CURRENT TEST SYSTEM USING REFLECTED FIELDS

Description: An eddy current test system is described in which the test information is detected as a series of fields reflected from the metal surface and interior. Pulsed electromagnetic fields are caused to impinge upon the test specimen. These fields are restricted to a small cross sectional area over a path in space long enough to be useful for test purposes by devices called mask-apenture assemblies. This approach provides a number of advantages over conventional eddy current methods of comparable capa… more
Date: June 11, 1962
Creator: Renken, C. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Characteristics of chars produced by pyrolysis following rapid heating of pulverized coal. [104 references]

Description: A 5.08-cm id pyrolysis furnace has been used to study pyrolysis following rapid heating of size graded pulverized coal particles as a function of isothermal pyrolysis time (0.018 to 1.025 second), particle size (50 to 181 ..mu..m), and parent coal (three lignites). The following experimental conditions were kept constant: Coal feed rate approximately equal to 0.5 g/min; volumetric flow rate of nitrogen temperature = 808/sup 0/C, and pressure = atmospheric. Under these conditions the heating rat… more
Date: February 1, 1977
Creator: Nsakala, N.; Walker, Jr., P. L. & Essenhigh, R. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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