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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

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

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

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

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

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

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

Materials Compatibility and Migration in Polymer Systems

Description: This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The purpose of this project to study the effects of materials migration by direct measurement of the diffusion and convective migration processes in complex polymeric materials and to develop appropriate predictive models. The use of isotopically tagged probe molecules to measure in-situ the diffusion of water in estane was demonstrated. A special environmental cell with a thin window was fabricated to enable real time measurements to be made under realistic conditions simulating actual operating parameters. Depth profiles were measured quantitatively using ion beam methods available at the Los Alamos Ion Beam Materials Laboratory. The Williams-Landau-Ferry model was adopted as a general expression for diffusion of a volatile material in a polymer. This model contains both thermal activation and free-volume change effects to account for the changes in polymeric structure with temperature and physical properties as embodied in the glass-transition temperature. A theoretical simulation of water migration in polyurethane was performed and compared to the ideal 1-D, constant temperature, constant-boundary concentration test problem, for which an analytical solution is known. The transport code works properly and indicates that time steps on the order of 10 minutes are permissible, which is the order of the time required to collect data for one measurement in the ion beam.
Date: July 10, 1999
Creator: Maggiore, C.J. & Valone, S.
Partner: UNT Libraries Government Documents Department

Geotechnical Analysis of Five Shelby Tube Samples from H-Area Retention Basin

Description: Geotechnical and geochemical analyses were performed on five Shelby tube samples collected in the H-Area Retention Basin (HRB) during July and August of 1998. The samples were collected as part of the HRB characterization study. The test results, which are documented in this report, will be used to support the HRB contaminant fate and transport modeling/analysis and to evaluate remedial options. The results will also be used as a base line for future treatability studies.
Date: June 2, 1999
Creator: Langton, C. A.
Partner: UNT Libraries Government Documents Department

Diagnostic study on retrieving bulk microphysical properties of low-level stratiform clouds and its implication on climate research

Description: The importance of low-level stratiform clouds to the planetary radiation balance is due to their persistence and coverage, and their effect on the planetary albedo. The vertical distribution of liquid water in these clouds is pertinent to many applications in atmospheric research. As a result, some cloud retrieval techniques have been developed with the assumptions, such as an adiabatic condition, no loss of liquid water via drizzle and/or a large liquid water path.
Date: March 1, 1998
Creator: Chin, H.-N.S.; Rodriguez, D.J.; Cederwall, R.T.; Chuang, C.C.; Grossman, A.S.; Yio, J.J. et al.
Partner: UNT Libraries Government Documents Department

Negative Electrodes for Li-Ion Batteries

Description: Graphitized carbons have played a key role in the successful commercialization of Li-ion batteries. The physicochemical properties of carbon cover a wide range; therefore identifying the optimum active electrode material can be time consuming. The significant physical properties of negative electrodes for Li-ion batteries are summarized, and the relationship of these properties to their electrochemical performance in nonaqueous electrolytes, are discussed in this paper.
Date: October 1, 2001
Creator: Kinoshita, Kim & Zaghib, Karim
Partner: UNT Libraries Government Documents Department

Nanostructured block copolymers.

Description: Block copolymers are well known to undergo micro-phase separation. Typical domain sizes range from a few to about 100 nanometers. With use of OPV{sub n-}PEG{sub m} diblock copolymers, long nanofiber, short nanorod, and lamella morphologies have been observed. OPV is oligo(phenylenevinylene) and PEG is poly(ethyleneglycol). The OPV segment is photoluminescent as well as electroluminescent. The micrometer long OPV{sub 13-}PEG{sub 45} nanofiber consists of OPV{sub 13} inner core with radius of 5.2 nm, and PEG{sub 45} outer shell with overall fiber radius of 7.9 nm. The nanorod has similar core-shell composition but with much shorter length of {approx}100 nm. Lamella morphology consists of alternating OPV and PEG layers. The structural characterization and physical properties of these nanostructured materials and their implication are summarized.
Date: July 9, 2002
Creator: Wang, H. H.; Wang, H.; Yu, L.; Han, C. Y.; Csencsits, R.; Willing, G. A. et al.
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