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in subjects: "Calcium Compounds"

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Direct oxide reduction demonstration, small-scale studies

This project was initiated to provide process design information to the Plutonium Recovery Project (PRP). Although direct oxide reduction (DOR) has been operated in a production mode both at the Rocky Flats Plant (now operated by EG G, Inc.) and Los Alamos National Laboratory, many aspects of the process are ill-defined. Because the PRP plans include significant DOR capability, a well-defined process should minimize capital cost and maximize productivity. Reduced radiation exposure may also be … more

Date: December 9, 1991

Creator: Long, J. L.; Santi, D. J.; Fisher, D. C. & Humiston, T. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Synchrotron and Laboratory Studies Utilizing a New Powder Diffraction Technique

We have developed a new type of powder diffractometer that is much more efficient than existing methods. The diffractometer has the potential of both high count rates and very high resolution when used at a synchrotron source. The laboratory based instrument has an order of magnitude improvement in count rate over existing methods. The method uses a focusing diffracted beam monochromator in combination with a multichannel detector. The incident x-rays fall on a flat plate or capillary sample an… more

Date: October 1, 1992

Creator: Knapp, G. S.; Beno, M. A.; Jennings, G.; Engbretson, M. & Ramanathan, M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Use of precalciners to remove alkali from raw materials in the cement industry. Quarterly technical progress report, November 1979-January 1980

Experiments using the sulfate fusion technique have continued. High degrees of alkali removal have been achieved using CaSO/sub 4/ admixtures with added CaCl/sub 2/ and Mg(NO/sub 3/)/sub 2/. The presence of Mg/sup 2 +/ or Cl/sup -/ in the mixtures did not affect the phase separation significantly. There was considerable evidence for preferential migration of K/sup +/ into the sulfate phase, relative to Na/sup +/. A new technique, the powder drop method, was used to attempt to more closely simul… more

Date: March 1, 1980

Creator: Gartner, Ellis M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Use of precalciners to remove alkali from raw material in the cement industry. Quarterly technical progress report, May-June 1979

Tests were made to determine the best method for volatilizing the alkalis in high-alkali clays, feldspars, and similar argillaceous materials. MgCl/sub 2/ was more effective in removing alkalis from feldspars than from the other minerals. Reducing conditions (graphite + CaCO/sub 3//CaCl/sub 2/) increased alkali volatility slightly exept in the case of illite. Water vapor had a negative effect. FeCl/sub 3/.6H/sub 2/O is not a very effective additive. Alkalis can be removed rapidly by heating to … more

Date: August 1, 1979

Creator: Gartner, Ellis M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Use of precalciners to remove alkalies from raw materials in the cement industry. Quarterly technical progress report, February--April 1979

Laboratory tests designed to evaluate the volatility of alkalies in finely-ground argillaceous minerals are reported. A method used to determine the sintering points of these minerals is described. In addition to six pure minerals which were studied, argillaceous materials which are more typical of cement-plant raw feed components were studied. The conclusions of this report are: at 1000/sup 0/C, a combination of CaCO/sub 3/ and CaCl/sub 2/ additives enables volatilizion in one-half hour up to … more

Date: May 1, 1979

Creator: Gartner, Ellis M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Use of precalciners to remove alkali from raw material in the cement industry. Quarterly technical progress report, August-October 1979

Research on methods for removing alkalies from argillaceous materials used to produce cement is reported. These methods include chloride volatilization, use of calcium sulfate to decompose the raw materials, alkali volatilization using amides of Na and K, and sulfate-fusion. (LCL)

Date: December 1, 1979

Creator: Gartner, Ellis M.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Development of high temperature scanning electron microscopy and applications to sintering studies

The densification and microstructural changes of a metallic and/or ceramic powder compact during sintering is a critically important but incompletely understood process. Whether solely in the solid state or in the presence of a liquid phase, mass transport occurs at elevated temperatures to eliminate porosity and reduce the surface energy of the system. Changes in specimen dimensions, particle shape and pore morphology, formation of liquid phases and other direct evidence of the sintering proce… more

Date: January 1, 1978

Creator: Wang, D. N. K.; Miller, D. J. & Fulrath, R. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Oxygen reduction at a stabilized zirconia interface with Y[sub 1-x]Ca[sub x]MnO[sub 3] or La[sub 1-x]Sr[sub x]MnO[sub 3] cathode materials

Impedance spectroscopy, combined with an unbonded interface cell, has been used to assess oxygen reduction behavior at interfaces between an yttria-stabilized zirconia electrolyte and perovskite or platinum cathode materials. Intrinsic oxygen reduction specific activities of Y[sub 1-x]Ca[sub x]MnO[sub 3] (x = 0.5, 0.6 and 0.7) and La[sub 1-x]Sr[sub x]MnO[sub 3] (x = 0.1 and 0.3) were determined as a function of temperature and oxygen partial pressure, independent of the interface morphology. Th… more

Date: May 1, 1993

Creator: Youngblood, G. E.; Pederson, L. R.; Bates, J. L. & Rupaal, A. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Novel approach to coal gasification using chemically incorporated catalysts (Phase II). Appendix A-F. Final report, May 1978-June 1981

This volume contains six appendices: experimental apparatus, test conditions, and results of catalytic coal treatment; direct hydrogasification; summary of test runs for hydrogasification of BTC; summary of test runs for hydrogasification of char; summary of steam/O/sub 2/ gasification runs; and process analysis. Forty tables and nine figures are also included.

Date: January 1, 1981

Creator: Feldmann, H. F.; Conkle, H. N.; Appelbaum, H. R. & Chauhan, S. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Novel approach to coal gasification using chemically incorporated catalysts (Phase II). Final report, May 1978-June 1981

Since 1974, Battelle has been developing a catalytic treatment process that would allow more economic, efficient and reliable utilization of the vast deposits of eastern coals in gasification systems. In order to keep the process simple and economic, a disposable catalyst lime (CaO), was employed. It was found that the effectiveness of low concentrations of CaO was greatly increased by thorough incorporation into the coal. As a result of these efforts, a catalytic treatment system has been deve… more

Date: January 1, 1981

Creator: Feldmann, H. F.; Conkle, H. N.; Appelbaum, H. R. & Chauhan, S. P.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Iowa State Mining and Mineral Resources Research Institute

This final report describes the activities of the Iowa State Mining and Mineral Resources Research Institute (ISMMRRI) at Iowa State University for the period July 1, 1989, to June 30, 1990. Activities include research in mining- and mineral-related areas, education and training of scientists and engineers in these fields, administration of the Institute, and cooperative interactions with industry, government agencies, and other research centers. During this period, ISMMRRI has supported resear… more

Date: August 1, 1990

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Fundamental studies of metal fluorination reactions. Third annual progress report

Results are presented of investigations of the solubility and diffusivity of fluorine in copper. Other research is reported on the electronic conductivity of CaF/sub 2/ electrolyte and mixed electrode reactions in solid electrolyte cells. (JRD)

Date: January 1978

Creator: Rapp, R. A.; Reddy, S. N. S.; Chou, S. F. & Lee, B. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Fundamental studies of metal fluorination reactions. Fourth annual progress report

In order to investigate the effects of oxygen on the electrical characteristics of the bulk and the electrode/electrolyte interface of CaF/sub 2/ electrochemical cells separately, the equivalent electrical circuits for the following cells were determined, and the geometric capacitances, the double-layer capacitances, the bulk conductivities and the interface conductivities were examined: Ni + NiF/sub 2//CaF/sub 2//Ni + NiF/sub 2/, Ni + NiO/CaF/sub 2//Ni + NiO, and Cu + Cu/sub 2/O/CaF/sub 2//Cu … more

Date: January 1979

Creator: Rapp, R. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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EXAFS studies of metamict materials

An important approach in the evaluation of crystalline wasteforms for nuclear waste storage is to study the long term stabilities of closely related radioactive mineral species which have become metamict (radiation damaged) and have been exposed to weathering processes for geologic periods of time. The metamictization and alteration effects can then be used for comparison with the results of short term laboratory leaching and irradiation experiments which have been designed to simulate long ter… more

Date: January 1, 1984

Creator: Greegor, R. B.; Lytle, F. W.; Ewing, R. C. & Haaker, R. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Energy transfer and non-linear optical properties at near ultraviolet wavelengths: Rare earth 4f yields 5d transitions in crystals and glasses

The following topics were studied: two-photon transitions from 4f ground state to 5d excited states in Ce{sup 3+}:CaF{sub 2}; optical absorption and photoionization measurements from excited state of Ce{sup 3+}:Y{sub 3}Al{sub 5}O{sub 12}; excited state photoionization of Ce{sup 3+} ions in Ce{sub 3+}:CaF{sub 2}; optical gain and loss studies in Ce{sup 3+}:LiYF{sub 4}; Gd {yields}Cr energy transfer in Cr{sup 3+}:GSGG, Cr{sup 3+}:GSAG and Cr{sup 3+}:GGG crystals; nonradiative relaxation in Ce{sup… more

Date: June 1, 1984

Creator: Hamilton, D. S.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Fundamental studies of metal fluorination reactions. Progress report, May 1, 1976--April 31, 1977

The present research is being undertaken to study some fundamental thermodynamic and transport properties and detailed mechanisms pertinent to metal fluorination reactions. The program consists of determining the following properties using solid-state, CaF/sub 2/-electrolyte galvanic cells: (A) solubility and diffusivity of fluorine in metals, specifically nickel, and (B) the nature of the point defects (type, concentration and mobility) in metal fluorides as a function of fluorine partial pres… more

Date: January 1977

Creator: Rapp, R. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Thin film processing and device fabrication in the Tl-Ca-Ba-Cu-O system

An obvious group of applications for high temperature superconducting (HTS) materials is microwave and millimeter wave circuitry. Besides low loss, unique features of these materials, such as flux flow, can be exploited. We have been concentrating on the Tl-Ca-Ba-Cu-O family of materials. The film growth techniques, lithographic processing methods and characteristics of several devices we have developed will be presented. These devices include a flux flow-based transistor with demonstrated oper… more

Date: January 1, 1990

Creator: Martens, J. S.; Ginley, D. S.; Zipperian, T. E.; Hietala, V. M. & Tigges, C. P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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CO^2 Formation Damage Study. Final Report.

The literature did provide insight into four possible damage mechanisms, namely: (1) precipitation of reservoir mineral in the vicinity around the producing well as carbon dioxide escapes from the water phase due to pressure draw down; (2) plugging of reservoir interstices by insoluble organic solids precipitated as the carbon dioxide dissolves in crude oil; (3) formation of an immobile gas phase, predominately CO/sub 2/, which would drastically lower the effective permeability to oil and, espe… more

Date: July 1, 1983

Creator: Patton, John T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Scaled-up testing of alternative trapping agents for radioactive constituents in plant vent streams

Radioactive discharges from the Portsmouth Gaseous Diffusion Plant vent streams are in compliance with present standards specifying radiation limits. Regulatory trends have become increasingly restrictive on the maximum permissible dose to a member of the public. This could mean more stringent controls for radioactive emissions in the future. Fixed bed activated alumina (Al/sub 2/O/sub 3/) trapping is currently the principal method of limiting plant vent stream emissions of technetium and urani… more

Date: January 1, 1982

Creator: Saraceno, A. J. & Reiter, N. F.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Carbon dioxide in geothermal fluids

The concentration of carbon dioxide was measured for the four production wells at the East Mesa Geothermal Test Site. The effects of flashing on the equilibria are discussed. The solubility product constant, K/sub sp/, for CaCO/sub 3/ is calculated at bottom hole temperatures.

Date: January 1, 1976

Creator: Papazian, Harold A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Thermal properties of Permian Basin evaporites to 493 K and 30 MPa confining pressure

Laboratory measurements have been made of the thermal conductivity and diffusivity of four rock salts, two anhydrites, and two dolomites bordering the Cycle 4 and Cycle 5 bedded salt formations in the Permian Basin in Deaf Smith County, Texas. Measurement conditions ranged from 303 to 473 K in temperature, and 0.1 to 31.0 MPa in hydrostatic confining pressure. Within the +-5% measurement resolution neither conductivity nor diffusivity showed a dependence upon pressure in any of the rocks. Condu… more

Date: January 26, 1987

Creator: Durham, W. B.; Heard, H. C.; Boro, C. O.; Keller, K. T.; Ralph, W. E. & Trimmer, D. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Corrosion studies in molten calcium chloride with chlorine

This study is aimed at testing new materials for use in molten salt processing of plutonium. Because of the high corrosiveness of chlorine, present materials have a high rate of failure. Materials less subject to corrosion are needed to minimize costs resulting from rapid failure of sparge tubes, stirring apparatus, and crucibles; to reduce the quantity of plutonium-contaminated scrap; and to improve the purity of the plutonium product. The processing environment of molten CaCl{sub 2}--CaO salt… more

Date: January 1, 1990

Creator: McLaughlin, D. F.; Sessions, C. E. & Marra, J. E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Effects of composition on sintering of current interconnects in SOFC

The sintering behavior of alkaline-earth-substituted lanthanum and yttrium chromites, which are candidates for the current interconnect in solid oxide fuel cells (SOFC) was investigated. Extensive commercialization of SOFC technology may involve co-sintering as a method to reduce production costs. Co-sintering will require that the interconnect material reaches high density (closed porosity) under conditions in which the air-electrode material, a manganite, maintains substantial porosity and re… more

Date: November 1, 1992

Creator: Chick, Larry A. & Bates, J. Lambert

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Uranium, thorium, and lead concentrations and lead isotopic composition of biotite granodiorite (sample 9527-2b) from LASL Drill Hole GT-2

An investigation of the uranium (U), thorium (Th), and lead (Pb) isotopic systematics was made on the whole rock, microcline, plagioclase, biotite, sphene, zircon, epidote, and pyrite of a biotite granodiorite (core sample 9527-2b) obtained from a depth of almost 3 km in Los Alamos Scientific Laboratory's (LASL) deep drill hole GT-2. Except for quartz, magnetite, and apatite, all primary mineral phases were analyzed, as were epidote and pyrite from minute epidote--calcite--pyrite veinlets forme… more

Date: July 1, 1979

Creator: Zartman, Robert E.

Item Type: Report

Partner: UNT Libraries Government Documents Department