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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

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

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

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

Preparation and Examination of Beryllium Carbide

Description: From abstract: "The properties of beryllium carbide were studied to determine its suitability as a high-temperature refractory. Various methods of preparing it were tried and a number of the physical and chemical properties of the resulting products were determined."
Date: 1953
Creator: Mallett, Manley William; Durbin, E. A.; Udy, M. C.; Vaughan, D. A. & Center, E. J.
Partner: UNT Libraries Government Documents Department

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

Energy Response and Physical Reoperties of NTA* Personnel NeutronDosimeter Nuclear Track Film

Description: This paper reports the chemical and physical properties of the NTA film packet. It correlates with these properties the response of this packet to neutrons of various energies. In this correlation the concept of the track unit is introduced as a basic unit for reporting film-packet response.
Date: March 13, 1961
Creator: Lehman, Richard L.
Partner: UNT Libraries Government Documents Department

Elastic and transport properties in polycrystals of crackedgrains: Cross-property relations and microstructure

Description: Some arguments of Bristow (1960) concerning the effects of cracks on elastic and transport (i.e., electrical or thermal conduction) properties of cold-worked metals are reexamined. The discussion is posed in terms of a modern understanding of bounds and estimates for physical properties of polycrystals--in contrast to Bristow's approach using simple mixture theory. One type of specialized result emphasized here is the cross-property estimates and bounds that can be obtained using the methods presented. Our results ultimately agree with those of Bristow, i.e., confirming that microcracking is not likely to be the main cause of the observed elastic behavior of cold-worked metals. However, it also becomes clear that the mixture theory approach to the analysis is too simple and that crack-crack interactions are necessary for proper quantitative study of Bristow's problem.
Date: October 2, 2007
Creator: Berryman, J.G.
Partner: UNT Libraries Government Documents Department

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

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

Analysis of sludge from K East basin floor and weasel pit

Description: Sludge samples from the floor of the Hanford K East Basin fuel storage pool have been retrieved and analyzed. Both chemical and physical properties have been determined. The results are to be used to determine the disposition of the bulk of the sludge and possibly assess the impact of residual sludge on dry storage of the associated intact metallic uranium fuel elements.
Date: May 4, 1996
Creator: Makenas, B.J., Westinghouse Hanford
Partner: UNT Libraries Government Documents Department

Top properties at the Tevatron

Description: We present the latest results associated with top properties at the Tevatron. The large data set collected in four years of running has allowed, after top discovery, the study of various top properties. The results presented here include the measurement of the CKM matrix element {vert_bar}V{sub if}{vert_bar}, the search for top FCNC, the study of properties of W in t decays and the search for heavy states decaying to tt pairs. Future measurements in top physics at the Tevatron are briefly discussed.
Date: May 1, 1997
Creator: Chiarelli, G. & Collaboration, The CDF
Partner: UNT Libraries Government Documents Department

Effects of Surface Chemistry on the Porous Structure of Coal

Description: In this report, 129 Xe nuclear magnetic resonance spectroscopy of xenon gas adsorbed in coal is used to describe some poorly understood features of coal microporous structure, particularly in establishing that a connected network exists, the type of connectivity, and its changes with the rank of coal. Micropore size scale and distribution are also considered. Two methods are developed which are new and versatile tools for the investigation of porous structure. Both utilize xenon gas that is in motion, while undergoing diffusion or exchange in coal, to describe the connectivity of the micropore structure of coal. Time tracking of the adsorption process by NMR, selective saturation, and saturation transfer techniques were used to obtain new information on the coal rank dependence of porous structure. In addition, an existing 129 Xe chemical shift-pore diameter model was used to calculate micropore diameters for coals, as well as for a microporous carbon, before and after pore-size alteration. In the initial study performed, straightforward 129 Xe NMR spectra at equilibrium xenon adsorption at a series of pressures were acquired for a rank-varied set of six coals. Acquisition of the NMR signal as an echo was tested and found to improve spectral quality. The spectra were used to calculate micropore diameters for the six coals. These range from 5.6 to 7.5 � and exhibit a minimum value for the intermediate coal rank. The smallest pores occur in coals of about 82-85% carbon; at both lower and higher coal ranks, the average micropore size tends to be larger. The changes in the spectra with coal rank and surface area were explored. Signal linewidths were found to decrease with increasing coal rank and were interpreted in terms of increasing chemical or physical homogeneity of the coal as rank increases. The packing density of powdered coal was found ...
Date: May 1, 1997
Creator: Radovic, Ljubisa R. & Hatcher, Patrick G.
Partner: UNT Libraries Government Documents Department

Thermodynamics of coherent open systems with applications to hydrides: The physical origin of hysteresis in absorption-desorption isotherms. [Final report]

Description: Purpose was to study the physical origin of a strong hysteresis on the pressure-composition isotherms of metal hydrides (plateau pressure during hydrogen absorption is several times higher than during reverse desorption). The research ended up studying the behavior of open coherent systems and the thermodynamics of an elastically coherent two-phase open system consisting of an interstitial solid solution in equilibrium with a gas reservoir of solute atoms.
Date: December 31, 1994
Creator: Khachaturyan, A. & Schwarz, R.
Partner: UNT Libraries Government Documents Department

Measurement techniques for evaluating encapsulant thermophysical properties during cure

Description: Sandia now has the capability to evaluate stresses during cure of epoxies with finite element codes. Numerous material parameters are needed as input to these codes. I present a relatively quick set of tests which enable evaluation of the required thermophysical properties. Ease and accuracy of the tests improve as the reaction rate of the thermoset slows. Material parameters for common encapsulants at Sandia are presented in tables.
Date: June 1, 1996
Creator: Adolf, D.
Partner: UNT Libraries Government Documents Department

A collection of wood properties. Version 1.1

Description: Reference books are the primary source of wood property data for use in research, school, or business. it has been our experience that obtaining the needed data from several references can be a cumbersome and time-consuming ordeal. These spreadsheets are a compilation of data from several well-known references. Version 1.1 includes the most recent update of commercial woods of the United States and the world. It is intended that they be used for quick summaries, comparisons, and calculations to increase the efficiency of the professional user in report preparation.
Date: September 1, 1992
Creator: Toennisson, R.L.
Partner: UNT Libraries Government Documents Department