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Final Technical Report

Description: The research project focuses on the following topics: a) removal of artifacts in the Doppler spectra from the ARM cloud radars, b) development of the second generation Active Remote Sensing of Cloud Layers (ARSCL) cloud data products, and c) evaluation of ARM cloud property retrievals within the framework of the EarthCARE simulator. We continue to pursue research on areas related to radiative transfer, atmospheric heating rates and related dynamics (topics of interest to the ARM science community at this time) and to contribute on an ad-hoc basis to the science of other ARM-supported principal investigators.
Date: February 22, 2010
Creator: Eugene Clothiaux, Johannes Verlinde, Jerry Harrington
Partner: UNT Libraries Government Documents Department
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Solid State Physics Program. Final Report

Description: During the 17 year period of this research, experimental and theoretical investigations were completed in many aspects of cohesive properties of metals and alloys and dielectric properties of various crystals and glasses together with the temperature and pressure derivatives of both properties. Studies of the magnetization and magnetic anisotropy indicate superparamagnetism is common in oligatomic condensed films and any decreased magnetic moment must be associated with surface atoms. Large intrinsic stresses are associated with growth morphology and impurities at grain boundaries. Transport properties in normal metals have been investigated theoretically. A number of basic theorems for disordered systems were derived. (204 references) (auth)
Date: June 1, 1975
Partner: UNT Libraries Government Documents Department
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Thorium ceramics data manual. Volume II. Nitrides. Revised

Description: Physical, chemical, and mechanical properties of thorium nitrides, alone and in combination with other nitrides and other thorium compounds. are collected from the literature through January 1973 (51 references). The thorium-nitrogen phase equilibrium is reviewed. Although mechanical property data are still sparse, recent physical and chemical characterization of ThN has confirined its high metallic conductivity, furnished detaii on hydrolysis and oxidation, and expanded the knowledge of the (Th,U)N and Th(C,N) systems. (auth)
Date: October 1, 1973
Creator: Peterson, S. & Curtis, C.E.
Partner: UNT Libraries Government Documents Department
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Tory II-C data book

Description: Declassified 26 Nov 1973. Information on Tory-2C is presented concerning reactor performance, neutronics, design parameters, test program, and physical properties of reactor materials. (DCC)
Date: June 17, 1963
Creator: Walter, C.E. & Smiley, P.C.
Partner: UNT Libraries Government Documents Department
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Issues and future directions in subsecond thermophysics

Description: The primary motivations for trying to measure thermophysical properties of materials on subsecond timescales are to extend measurements to higher temperatures than can be conveniently maintained continuously, or to make measurements on systems out of thermodynamic equilibrium. Since these measurements are difficult, one must keep in mind the needs for the data. These include the ability to use materials cleverly in new high-pressure/high- temperature applications, as well as the development of calibrated models for the response of materials to rapid energy deposition, by laser pulses, for example. Several key areas have been identified in which effort is needed for substantial progress in subsecond measurements, and which have unusual promise for useful new scientific results. These areas include the problems of high-temperature standards, equilibration during rapid heating, measurements at higher temperatures combined with higher pressures, measurements on specific interesting materials, and measurement of microstructural properties at high temperature and their relation to macroscopic response. Each of these areas will be touched upon here.
Date: January 1, 1989
Creator: Shaner, J.W.
Partner: UNT Libraries Government Documents Department
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Statistical Analysis and Geologic Evaluation of Laboratory-Derived Physical Property Data for Selected Nevada Test Site Core Samples of Non-Zeolitized Tuffs

Description: A statistical analysis and geologic evaluation of recently acquired laboratory-derived physical property data are being performed to better understand and more precisely correlate physical properties with specific geologic parameters associated with non-zeolitized tuffs at the Nevada Test Site. Physical property data include wet and dry bulk density, grain density (i.e., specific gravity), total porosity, and effective porosity. Geologic parameters utilized include degree of welding, lithology, stratigraphy, geographic area, and matrix mineralogy (i.e., vitric versus devitrified). Initial results indicate a very good correlation between physical properties and geologic parameters such as degree of welding, lithology, and matrix mineralogy. However, physical properties appear to be independent of stratigraphy and geographic area, suggesting that the data are transferrable with regards to these two geologic parameters. Statistical analyses also indicate that the assumed grain density of 2.65 grams per cubic centimeter used to calculate porosity in some samples is too high. This results in corresponding calculated porosity values approximately 5 percent too high (e.g., 45 percent versus 40 percent), which can be significant in the lower porosity rocks. Similar analyses and evaluations of zeolitic tuffs and carbonate rock physical properties data are ongoing as well as comparisons to geophysical log values.
Date: April 20, 2009
Creator: National Security Technologies, LLC
Partner: UNT Libraries Government Documents Department
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Selected physicochemical properties of basaltic rocks, liquids, and glasses

Description: Fundamental data on properties of rocks are required for the engineering development of rock-melting systems (Subterrenes). Selected physicochemical propenties of basaltic rocks, liquids, and glasses are presented including viscosity, thermal diffusivity, thermal conductivity, specific heat, density, thermal expansion coefficient, and average chemical composition. (auth)
Date: March 1, 1974
Creator: Krupka, M.C.
Partner: UNT Libraries Government Documents Department
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Preparation and Physical Properties of Uranium Hydride

Description: Report discussing the preparation of uranium hydride and its properties such as density, crystal structure, and number of atoms per unit cell. From abstract: "The pressure-composition isotherm as well as other data indicates that uranium hydride is a true compound."
Date: 1948
Creator: Spedding, F. H.; Newton, A. S.; Johns, I. B.; Johnson, O.; Daane, A.; Nottorf, R. W. et al.
Partner: UNT Libraries Government Documents Department
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Study of the temperature dependence of spin-wave excitations in Fe/sub x/Cr/sub 1-x/

Description: Certain alloys of Fe/sub x/Cr/sub 1-x/ (0.18 < x < 0.30) have been reported to undergo a transition from a ferromagnetic state to one exhibiting mictomagnetic or spin-glass behavior at temperatures below the Curie temperature, T/sub c/. Studies of the critical scattering on polycrystalline samples show a peak at T/sub c/ for all x's and a monotonically decreasing intensity for T < T/sub c/ for x > 0.30. For those x's exhibiting spin-glass behavior, there is an increase in intensity at low temperatures. The dynamical studies reveal well-defined spin waves within the ferromagnetic regime but as T approaches the spin-glass phase, the magnetic stiffness decreases dramatically.
Date: January 1, 1980
Creator: Shapiro, S.M.; Fincher, C.R. Jr.; Palumbo, A.H. & Parks, R.D.
Partner: UNT Libraries Government Documents Department
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Physical motivations of the constitutive relations for ferroelectric ceramics and the existence of butterfly and hysteresis loops

Description: The responses of ferroelectric ceramics can be quite complex depending on the physical processes to which they are subjected. Their mechanical, electromechanical and dielectric properties depend on domain switching, dipole dynamics and phase transformation which can be caused by external stimuli such as mechanical and electrical loadings, and temperature variations. A theory, taking into account the effects of domain switching and dipole dynamics, has been formulated, and in its present stage of development is sufficient to characterize various observable resonses. Specifically, a special case of the theory predicts the nature of the butterfly and hysteresis loops. The butterfly and hysteresis loops are manifestations of the mechanical, electro-mechanical and dielectric responses due to domain switching produced by cyclic electric fields. Comparisons of the predictions of the theory with experimental results are made in a pseudo one dimensional context.
Date: January 1, 1982
Creator: Chen, P.J.
Partner: UNT Libraries Government Documents Department
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A system for measuring the attenuation of X-rays by various materials

Description: The Filter Attenuation Measurement System was designed by J.H. McCrary. It is, as its name implies, primarily intended to measure the attenuation of an x-ray beam by various substances. However, it can also be a very useful instrument for qualitative as well as quantitative analysis through the use of absorption edge spectrometry. The essential components of the system are depicted. The brehmstrahlung originating in a tungsten target x-ray tube is collimated and the desired energy picked out by varying the angle that the primary beam makes with the (200) set of planes in a LiF crystal. The reflected beam, which is monochromatic, passes through two collimators before being detected by a NaI counter. The sample whose transmissivity is being measured is placed between the second and third collimators.
Date: October 25, 1971
Creator: Singman, L. V.
Partner: UNT Libraries Government Documents Department
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Reflectance measurements of vacuum-deposited aluminum films

Description: An integrating sphere technique was used for the measurement of the total and specular reflectance of vacuum-evaporated aluminum films. The appearance of the surface to the naked eye was relatively insensitive to the total reflectance, but was very closely related to the fraction of reflected light that was specularly reflected. Milky or cloudy-appearing aluminum films had a low specular reflectance while mirror-like films had a high specular reflectance. Surface specular reflectance was in turn closely related to film microtopography; roughening features such as hillocks substantially reduced film shininess and hence specular reflectance. Although no extensive study to relate reflectance to deposition parameters was undertaken, specular reflectance was found to be very sensitive to chamber pressure during evaporation. Two alternate techniques for surface appearance measurements were evaluated and correlated with the integrating sphere method; these techniques yielded relative assessments of film shininess that corresponded well with visual appearance and integrating sphere results.
Date: March 24, 1977
Creator: Sherman, D. M.
Partner: UNT Libraries Government Documents Department
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Effects of Resin Coating Methods and Other Variables on Physical Properties of Glass-Fabric Reinforced Polyesters

Description: Memorandum presenting the effects of resin coating methods on some physical properties of laminates prepared with glass fabric, Fiberglas 181, and bonded with two commercial polyester resins. The resins used were Laminac 4126 and Selectron 5003. The resin coating methods used were roller coating, application of a dilute solution of resin, resin immersion, application of monomeric styrene, and vacuum impregnation.
Date: August 23, 1954
Creator: Axilrod, B. M.; Wier, J. E. & Mandel, J.
Partner: UNT Libraries Government Documents Department
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Electronic properties of silicon grain boundaries

Description: Polycrystalline silicon is a clean and relatively simple prototype of electronic ceramics. The theory of the electrostatic barriers which form at silicon grain boundaries will be discussed. The use of experimental conductance and capacitance measurements to obtain the barrier height and energy density of grain boundary states will be illustrated.
Date: January 1, 1980
Creator: Pike, G. E. & Seager, C. H.
Partner: UNT Libraries Government Documents Department
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Improved Efficiency of Miscible C02 Floods and Enhanced Prospects for C02 Flooding Heterogeneous Reservoirs

Description: Surfactant and foam properties have been evaluated at high pressure using the foam durability apparatus. For a number of surfactant solutions the interfacial tension with cense CO2, critical micelle concentrations, foaming ability, and foam stability were determined. Preliminary results show that these tests correlate well to predict surfactant properties and mobility in cores. Work has also restarted in the parallel-dual permeability system.
Date: October 10, 1996
Creator: Guo, Boyn (Gordon); Schechter, David S.; Tsau, Jyun-Syung; Grigg, Reid B. & Chang, Shih-Hsien (Eric)
Partner: UNT Libraries Government Documents Department
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Caustic rings of dark matter

Description: It is shown that the infall of collisionless dark matter onto isolated galaxies produce a series of caustic rings in the halo dark matter distribution. The properties of these caustics are investigated. It is found in particular that the density profile of the caustic behaves as the inverse distance to the ring. Bumps in the rotation curve of NGC 3198 are interpreted as due to caustic rings of dark matter.
Date: May 6, 1997
Creator: Sikivie, P.
Partner: UNT Libraries Government Documents Department
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