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in subjects: "Aluminium Compounds"

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Sintering of polycrystalline ionic conductors:. beta. ''-Al/sub 2/O/sub 3/ and NASICON

The densification kinetics for both ..beta..''-alumina and NASICON are dramatically different. ..beta..''-Alumina sinters by a reactive liquid process whereas NASICON densifies by a solid state method. More importantly, a qualitative examination of particle and agglomerate distributions, phase composition, linear shrinkage analysis, and heating rate effects can result in a concise determination of sintering processes without recourse to more quantitative techniques. Such a s… more

Date: January 1, 1979

Creator: McEntire, B. J.; Miller, G. R. & Gordon, R. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High temperature ceramic membrane reactors for coal liquid upgrading

In this project we intend to study a novel process concept, i.e, the use of ceramic membranes reactors in upgrading of coal derived liquids. Membrane reactors have been used in a number of catalytic reaction processes in order to overcome the limitations on conversion imposed by thermodynamic equilibrium. They have, furthermore, the inherent capability for combining reaction and separation in a single step. Thus they offer promise for improving and optimizing yield, selectivity and performance … more

Date: January 1, 1992

Creator: Tsotsis, T.T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Irradiation experiment for lithium ceramics

Solid breeder materials are required in D-T fusion reactor blankets to convert fusion neutrons to tritium and thermal energy while providing some neutron shielding for the magnets. Lithium compounds such as Li/sub 2/O, LiAlO/sub 2/, Li/sub 4/SiO/sub 4/ and Li/sub 2/ZrO/sub 3/ have been proposed as solid breeder materials. Tritium is necessary to maintain the fuel supply for the D-T fusion reaction. No high burnup irradiation performance data is available for these materials in a neutron environ… more

Date: March 1, 1982

Creator: Hollenberg, G.W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Phosphate-bonded glass cements for geothermal wells. Final report

Calcium aluminosilicate glasses were found to react with phosphoric acid in three ways depending upon silica content. Above 55% SiO/sub 2/ they are insoluble while below 50% they dissolve readily. The transition compositions release calcium and aluminum ions and a silica gel phase replaces the glass. Activation energies in the order of 10 kcal/mole are associated with the dissolution. Equilibrium studies in the systems CaO-P/sub 2/O/sub 5/-H/sub 2/O, Al/sub 2/O/sub 3/-P/sub 2/O/sub 5/-H/sub 2/O… more

Date: September 1, 1979

Creator: Rockett, T.J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Pacific Northwest Laboratory Report on Fusion Energy Research, April 1977 - June 1977

The development of economic data for fusion power plants continued in a study estimating the potential impact of a shortage of materials important in fusion plant construction. In studies developing heat transfer and fluid flow design tools for fusion reactor blankets, preconceptual design studies were initiated to identify the potential design limits of water cooling in the first wall of Tokamak Next Step (TNS) concepts. In surface effects research clean gold samples were irradiated in the Uni… more

Date: July 1, 1977

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

High temperature ceramic membrane reactors for coal liquid upgrading

In this project we will study a novel process concept, i.e., the use of ceramic membrane reactors in upgrading of coal model compounds and coal derived liquids. In general terms, the USC research team is responsible for constructing and operating the membrane reactor apparatus and for testing various inorganic membranes for the upgrading of coal derived asphaltenes and coal model compounds. The USC effort will involve the principal investigator of this project and two graduate research assistan… more

Date: January 1, 1992

Creator: Tsotsis, T.T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Vapor phase spectroscopy of complex lanthanide halide--aluminum halide molecular species

The absorption spectrum of ErCl/sub 3/ (AlCl/sub 3/)/sub x/ vapor complex was measured and analyzed using the Judd-Ofelt theory. Structural correlations in other AlCl/sub 3/ vapor complexes and radiation emission are discussed. Fluorescence of TbCl/sub 3/ (AlCl/sub 3/)/sub x/ vapor complex and in the NdCl/sub 3/ (AlCl/sub 3/)/sub x/ system were studied. (DLC)

Date: January 1, 1977

Creator: Carnall, W T; Hessler, J P; Williams, C W & Hoekstra, H R

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Analysis of valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/(YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 2/ (Ruby), a study of certain properties of these laser materials related to their valence-electron structures

A direct method of determination of the valence-electron structure from its crystal structure has been presented by the writer at XIIth International Congress of Crystallography, at Ottawa, 1981. Here the method is applied to determine the valence-electron structures of Y/sub 3/Al/sub 5/O/sub 12/ (YAG) and Al/sub 2/O/sub 3/, Cr/sub 2/O/sub 3/ (ruby) to see how certain properties of these laser materials are related to their valence-electron structures. The first point observed is the very stron… more

Date: January 1, 1982

Creator: Yu, S. H. & Yu, L. H.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Ceramic microstructures and their elucidation by imaging, diffraction and spectroscopic methods

The development and potential utilization of ceramic materials is dependent on a systematic effort involving processing, characterization and appropriate property measurements. The methods of characterization are numerous and it is important to employ the one that is appropriate to the problem both in terms of its information content and the achievable level of resolution. With the incorporation of fine probe forming capabilities in a transmission electron microscope and the development of rela… more

Date: February 1, 1992

Creator: Kirshnan, K.M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

High-temperature oxidation and corrosion of materials program

Research progress is reported in the behavior of metals and alloys in gas mixtures at high temperature, corrosion mechanisms in complex environments of low oxidizing potential, hot corrosion of nickel-base alloys at intermediate temperatures, corrosion of solid sulfate deposits, adherence of Al/sub 2/O/sub 3/ oxide films, oxidation behavior of a two-phase alloy Fe-44% Cu, and formation of subscales of varying composition. (FS)

Date: March 1, 1980

Creator: Whittle, D.P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

A design of experiment study of plasma sprayed alumina-titania coatings

An experimental study of the plasma spraying of alumina-titania powder is presented in this paper. This powder system is being used to fabricate heater tubes that emulate nuclear fuel tubes for use in thermal-hydraulic testing. Coating experiments were conducted using a Taguchi fractional-factorial design parametric study. Operating parameters were varied around the typical spray parameters in a systematic design of experiments in order to display the range of plasma processing conditions and t… more

Date: January 1, 1992

Creator: Steeper, T. J. (Du Pont de Nemours (E.I.) and Co., Aiken, SC (United States). Savannah River Lab.); Varacalle, D. J. Jr.; Wilson, G. C. (EG and G Idaho, Inc., Idaho Falls, ID (United States)); Riggs, W. L. II (Tubal Cain Co., Loveland, OH (United States)); Rotolico, A. J. & Nerz, J. E. (Metco/Perkin-Elmer, Westbury, NY (United States))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Mechanical strength and stability of lithium aluminate

Pacific Northwest Laboratory (PNL) investigated the strength and resistance to thermal shock of lithium aluminate annular pellets. The room temperature, axial compressive fracture strength of pellets made at Westinghouse Advanced Energy Systems (WAES) varied from 80 to 133 ksi. The strength at 430{degrees}C (806{degrees}F) was to 30 to 40% lower. The strength at 900{degrees}C (1652{degrees}F) showed a wide variation with one measurement near 90 ksi. These strength values are consistent with oth… more

Date: June 1, 1992

Creator: Brimhall, J.L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Development and evaluation of die and container materials. Final report

Specific compositions of high purity silicon aluminum oxynitride (Sialon) and silicon beryllium oxynitride (Sibeon) solid solutions are shown to be promising refractory materials for handling and manipulating solar grade silicon into silicon ribbon. Well controlled processing schedules were developed for fabricating high purity Sialon and Sibeon materials. Essentially the impurity content of the hot pressed ceramics was due only to impurities from the original starting powders. A ceramic shapin… more

Date: May 1, 1979

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Creep of whisker-reinforced ceramics

The results of high-temperature creep of various ceramic composites will be reviewed. In particular, creep results for Al{sub 2}O{sub 3} and Si{sub 3}N{sub 4} matrices reinforced with SiC whiskers will be emphasized. For a given temperature, stress and grain size, the creep rate of the Al{sub 2}O{sub 3} composite is usually lower than that of the ceramic matrix. In general, creep at low stresses occurs by grain boundary sliding accommodated by diffusion, whereas higher stresses lead to damage a… more

Date: January 1, 1991

Creator: Routbort, J.L; Goretta, K.C. (Argonne National Lab., IL (United States)); Dominguez-Rodriguez, A. & de Arellano-Lopez, A.R. (Seville Univ. (Spain))

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Process and analytical studies of enhanced low severity co-processing using selective coal pretreatment

This report describes progress on research during the eleventh quarter of this contract dealing with applications of coal pretreatment techniques in coal/oil co-processing and direct hydroliquefaction. The objectives of the project are to investigate various coal pretreatment techniques and to determine the effect of these pretreatment procedures on the reactivity of the coal. Reactivity enhancement will be evaluated under both direct hydroliquefaction and co-processing conditions. Coal convers… more

Date: 1991-06~

Creator: Baldwin, R. M.; Gaur, S. & Miller, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Array automated assembly: Phase 2. Quarterly report

An analysis was made of cost trade-offs for shaping modified square wafers from cylindrical crystals. For reasonably expectable silicon and sheet costs, the optimum shape will be nearer a circle than a square. Tests were conducted of the effectiveness of texture etching for removal of surface damage on sawed wafers. Four glass systems have survived preliminary screening tests for use as edge masking dielectrics. These include beta-spodumen, MgO-Al/sub 2/O/sub 3/ borosilicate, baria and titania … more

Date: February 1, 1978

Creator: Taylor, W.E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Effect of irradiation-induced defects on fusion reactor ceramics

Structural, thermal, and electrical properties critical to performance of ceramics in a fusion environment can be profoundly altered by irradiation effects. Neutron damage may cause swelling, reduction of thermal conductivity, increase in dielectric loss, and either reduction or enhancement of strength depending on the crystal structure and defect content of the material. Absorption of ionizing energy inevitably leads to degradation of insulating properties, but these changes can be reduced by … more

Date: January 1, 1986

Creator: Clinard, F.W. Jr.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Anisotropic dislocation loop nucleation in ion-irradiated MgAl sub 2 O sub 4

Polycrystalline disks of stoichiometric magnesium aluminate spinel (MgAl{sub 2}O{sub 4}) were irradiated with 2 MeV Al{sup +} ions at 650{degrees}C and subsequently analyzed in cross-section using transmission electron microscopy (TEM). Interstitial dislocation loops were observed on 110 and 11 habit planes. The population of loops on both sets of habit planes was strongly dependent on their orientation with respect to the ion beam direction. The density of loops with habit plane normals nearly… more

Date: January 1, 1991

Creator: Zinkle, S. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Dynamic shear behavior of alumina-filled epoxy

Thin-walled tubular specimens of alumina-filled epoxy were loaded in torsion at a strain rate of approximately 10/sup 3/ s/sup -1/ using a stored-torque Kolsky bar. In addition to measuring the time resolved shear stress and shear strain in the specimen, the axial stress generated by the dilation of the material during shear deformation was also obtained as a function of time. Tests were conducted at room temperature and at -60/sup 0/C. At room temperature, a moderate amount of plastic deformat… more

Date: March 1, 1982

Creator: Costin, L.S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Arsenic Removal From Gaseous Streams

Uranium feed materials, depending on the production process, have been found to contain arsenic (As) as a contaminant. Analyses show the As to be present as As pentafluoride (AsF{sub 5}) and/or hexafluoroarsenic acid (HAsF{sub 6}) and enter the enrichment cycle through contaminated hydrogen fluoride (HF). Problems related to corrosion of cylinder valves and plugging of feed lines and valves have been attributed to the As. Techniques to separate AsF{sub 5} from uranium hexafluoride (UF{sub 6}) u… more

Date: November 22, 1989

Creator: Russell, R. G. & Otey, M. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Stability and compatibility studies with the inorganic explosive 2-(5-cyanotetrazolato)pentaamminecobalt(III) perchlorate (CP)

2-(5-Cyanotetrazolato)pentaamminecobalt(III) perchlorate (CP) is an inorganic secondary explosive that has been developed for applications involving deflagration-to-detonation transition. Previously the primary explosives lead azide and lead styphnate had been used. Stability and compatibility studies with CP have been conducted for periods up to three years. By using the rate of formation of cobalt(II) as the prime stability measurement for CP no reaction above baseline has been observed at te… more

Date: January 1, 1980

Creator: Massis, T. M.; Morenus, P. K.; Huskisson, D. H. & Merrill, R. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Probe molecule studies: Active species in alcohol synthesis

The goal of this research is to develop a better understanding of the mechanisms of formation of alcohols and other oxygenates from syngas over supported catalysts. Probe molecules will be added in situ during the reaction to help delineate reaction pathways and identify reaction intermediate species. The key of our study is to investigate how the species generated by these probe molecules interact with surface species present during oxygenate formation.

Date: April 1, 1992

Creator: Blackmond, D.G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

MHD air heater development technology. Progress report, November 26, 1979-March 31, 1980

Work on the development of the directly-fired high temperature air heater (HTAH) for MHD power plants is reported. Progress is reported on three tasks: (1) materials selection, evaluation, and development, (2) operability, performance, and materials testing, and (3) full-scale design concepts. Under Task 1, efforts were carried out in several areas. Work on the computer data base for material properties was begun. Data were compiled for several HTAH materials. Materials selections for Valve Tes… more

Date: May 1, 1980

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Advanced high efficiency concentrator cells

This report describes research to develop the technology needed to demonstrate a monolithic, multijunction, two-terminal, concentrator solar cell with a terrestrial power conversion efficiency greater than 35%. Under three previous subcontracts, Varian developed many of the aspects of a technology needed to fabricate very high efficiency concentrator cells. The current project was aimed at exploiting the new understanding of high efficiency solar cells. Key results covered in this report are as… more

Date: June 1, 1992

Creator: Gale, R. (Varian Associates, Inc., Palo Alto, CA (United States). Varian Research Center)

Item Type: Report

Partner: UNT Libraries Government Documents Department