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9519 biotite granodiorite reacted in a temperature gradient

Description: A biotite granodiorite from the Fenton Hill Hot Dry Rock (HDR) geothermal system was reacted in a controlled temperature gradient with initially distilled water for 60d. Polished rock prisms were located in the gradient at 72, 119, 161, 209, 270, and 310/sup 0/C. Scanning electron microscope and microprobe analyses show the appearance of secondary phases: Ca-montmorillonite at 72/sup 0/C and 119/sup 0/C; zeolite, either stilbite or heulandite, at 161/sup 0/C; and another zeolite, thomsonite, at… more
Date: October 1, 1980
Creator: Charles, R. W. & Bayhurst, Gregory K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Abiotic Degradation Rates for Carbon Tetrachloride: and Chloroform: Progress in FY 2008

Description: This is a letter report summarizing work performed in FY2008 to determine the rates of carbon tetrachloride hydrolysis at temperatures close to actual groundwater temperatures. The report describes the project, the methodology, and the results obtained since the project's inception in FY2006. Measurements of hydrolysis rates in homogeneous solution have been completed for temperaturs of 70 C through 40 C, with additional data available at 30 C and 20 C. These results show no difference between … more
Date: October 31, 2008
Creator: Amonette, James E.; Jeffers, Peter M.; Qafoku, Odeta; Russell, Colleen K.; Wietsma, Thomas W. & Truex, Michael J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Abiotic Degradation Rates for Carbon Tetrachloride and Chloroform: Progress in FY2009

Description: This report documents the progress made through FY 2009 on a project initiated in FY 2006 to help address uncertainties related to the rates of hydrolysis in groundwater for carbon tetrachloride (CT) and chloroform (CF). The study seeks also to explore the possible effects of contact with minerals and sediment (i.e., heterogeneous hydrolysis) on these rates. In previous years the work was funded as two separate projects by various sponsors, all of whom received their funding from the U.S. Depar… more
Date: March 2010
Creator: Amonette, James E.; Jeffers, Peter M.; Qafoku, Odeta; Russell, Colleen K.; Wietsma, Thomas W. & Truex, Michael J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Abrasive wear by coal-fueled diesel engine and related particles

Description: The development of commercially viable diesel engines that operate directly on pulverized coal-fuels will require solution to the problem of severe abrasive wear. The purpose of the work described in this report was to investigate the nature of the abrasive wear problem. Analytical studies were carried out to determine the characteristics of the coal-fuel and associated combustion particles responsible for abrasion. Laboratory pinon-disk wear tests were conducted on oil-particle mixtures to det… more
Date: September 1, 1992
Creator: Ives, L. K. (National Inst. of Standards and Technology, Gaithersburg, MD (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Abrasive wear by coal-fueled diesel engine and related particles

Description: The development of commercially viable diesel engines that operate directly on pulverized coal-fuels will require solution to the problem of severe abrasive wear. The purpose of the work described in this report was to investigate the nature of the abrasive wear problem. Analytical studies were carried out to determine the characteristics of the coal-fuel and associated combustion particles responsible for abrasion. Laboratory pinon-disk wear tests were conducted on oil-particle mixtures to det… more
Date: September 1, 1992
Creator: Ives, L. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Abrasive wear by diesel engine coal-fuel and related particles

Description: The purpose of the work summarized in this report was to obtain a basic understanding of the factors which are responsible for wear of the piston ring and cylinder wall surfaces in diesel engines utilizing coal-fuel. The approach included analytical studies using scanning electron microscopy and energy dispersive x-ray analyses to characterize coal-fuel and various combustion particles, and two different wear tests. The wear tests were a modified pin-on-disk test and a block-on-ring test capabl… more
Date: September 1, 1994
Creator: Ives, L. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Abrasive wear in ceramics: an assessment

Description: The mechanisms of material removal during abrasive wear were examined, and preliminary analyses presented. Primary emphasis has been placed on the lateral fracture mechanism, in an attempt to elucidate both its realm of importance and the concomitant material removal rates. Thermal stresses induced by plastic penetration have also been shown to be a potential source of material removal, especially at low levels of the normal force.
Date: January 1, 1979
Creator: Evans, A.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Absolute Abundance of the Chromium Isotopes in Some Secondary Minerals

Description: From abstract: "Isotopic assays have been made on the chromium in samples from fourteen different chrominiferous minerals from different geographic and meteoritic sources. The results of the assays indicate that it is not possible to unequivocally state that variations in isotopic compositions have been observed."
Date: 1962
Creator: Svec, Harry J. (Harry John), 1918-; Flesch, G. D. & Capellen, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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THE ABSOLUTE ABUNDANCE OF THE CHROMIUM ISOTOPES IN SOME SECONDARY MINERALS

Description: Isotopic assays have been made on the Cr in samples from 14 different chrominiferous minerals from different geographic and meteoritic sources. The results of the assays indicate that it is not possible to state unequivocally that variations in isotopic composition have been observed. (auth)
Date: March 14, 1962
Creator: Svec, H. J.; Flesch, G. D. & Capellen, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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AC microcalorimetry of adsorbates on evaporated metal films: Orientational ordering of H₂ multilayers

Description: We have improved and extended a novel ac calorimetric technique for measuring the heat capacity of adsorbates on evaporated metal films. Metallic substrates are of particular interest in current studies of the thermodynamics of adsorbed molecules. The method described in the present work is only calorimetric technique which allows measurements of molecules on simple metallic surfaces. Among other improvements, we have achieved significant progress in the preparation and characterization of the … more
Date: November 1, 1991
Creator: Phelps, R.B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Accelerated aging tests of liners for uranium mill tailings disposal

Description: This document describes the results of accelerated aging tests to determine the long-term effectiveness of selected impoundment liner materials in a uranium mill tailings environment. The study was sponsored by the US Department of Energy under the Uranium Mill Tailings Remedial Action Project. The study was designed to evaluate the need for, and the performance of, several candidate liners for isolating mill tailings leachate in conformance with proposed Environmental Protection Agency and Nuc… more
Date: November 1, 1981
Creator: Barnes, S. M.; Buelt, J. L. & Hale, V. Q.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Acord 1-26 hot, dry well, Roosevelt Hot Springs hot dry rock prospect, Utah

Description: The Acord 1-26 well is a hot, dry well peripheral to the Roosevelt Hot Springs known geothermal resource area (KGRA) in southwestern Utah. The bottom-hole temperature in this 3854-m-deep well is 230/sup 0/C, and the thermal gradient is 54/sup 0/C/km. The basal 685 m, comprised of biotite monzonite and quartz schist and gneiss, is a likely hot, dry rock (HDR) prospect. The hole was drilled in a structural low within the Milford Valley graben and is separated from the Roosevelt KGRA to the east b… more
Date: August 1, 1983
Creator: Shannon, S.S. Jr.; Pettitt, R.; Rowley, J.; Goff, F.; Mathews, M. & Jacobson, J.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Acoustic and electrical properties of Mexican geothermal rock samples

Description: Acoustic compressional and shear-wave velocities have been measured on a suite of ten sandstone samples obtained from wells in the Cerro Prieto geothermal field and on two rock samples from other Mexican geothermal fields. The samples were tested in both their dry and fully brine-saturated states at uniaxial stresses to 15 MPa. Electrical resistivities and associated phase angles have been measured on the same core samples as a function of frequency in the range 10 Hz to 10/sup 5/ Hz under drai… more
Date: December 1, 1984
Creator: Contreras, E. A. & King, M. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Actinide removal from aqueous solution with activated magnetite

Description: An actinide aqueous waste treatment process using activated magnetite has been developed at Rocky Flats. The use and effectiveness of various magnetites in lowering actinide concentrations in aqueous solution are described. Experiments indicate that magnetite particle size and pretreatment (activation of the magnetite surface with hydroxyl ions greatly influence the effective use of magnetite as an actinide adsorbent. With respect to actinide removal, Ba(OH)/sub 2/-activated magnetite was more … more
Date: August 10, 1987
Creator: Kochen, R.L. & Thomas, R.L. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Active metasomatism in the Cerro Prieto geothermal system, Baja California, Mexico: a telescoped low pressure/temperature metamorphic facies series

Description: In the Cerro Prieto geothermal field, carbonate-cemented, quartzofeldspathic sediments of the Colorado River delta are being actively metasomatized into calc-silicate metamorphic rocks by reaction with alkali chloride brines between 200/sup 0/ and 370/sup 0/C, low fluid and lithostatic pressures, and low oxygen fugacities. Petrologic investigations of drill cores and cutting from over 50 wells in this field identified a prograde series of calc-silicate mineral zones which include as index miner… more
Date: January 1, 1983
Creator: Schiffman, P.; Elders, W. A.; Williams, A. E.; McDowell, S. D. & Bird, D. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Activity composition relationships in silicate melts

Description: Equipment progress include furnace construction and electron microprobe installation. The following studies are underway: phase equilibria along basalt-rhyolite mixing line (olivine crystallization from natural silicic andensites, distribution of Fe and Mg between olivine and liquid, dist. of Ca and Na between plagioclase and liquid), enthalpy-composition relations in magmas (bulk heat capacity of alkali basalt), density model for magma ascent and contamination, thermobarometry in igneous syste… more
Date: January 1, 1990
Creator: Glazner, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Activity composition relationships in silicate melts. Final report

Description: Equipment progress include furnace construction and electron microprobe installation. The following studies are underway: phase equilibria along basalt-rhyolite mixing line (olivine crystallization from natural silicic andensites, distribution of Fe and Mg between olivine and liquid, dist. of Ca and Na between plagioclase and liquid), enthalpy-composition relations in magmas (bulk heat capacity of alkali basalt), density model for magma ascent and contamination, thermobarometry in igneous syste… more
Date: December 31, 1990
Creator: Glazner, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Adaptive optics for high power beam lines using diamond crystal monochromators

Description: Preserving the high source brightness of the third generation of synchrotron radiation facilities will require that thermal and pressure deformations of the monochromator crystals be maintained within a few arc- seconds. Recent experiments at the National Synchrotron Light Source (NSLS) have demonstrated the potential of adaptive crystal optics to cope with high power densities. In this technique the crystals deformations are minimized both by an efficient water-jet cooling and by externally ap… more
Date: January 1, 1992
Creator: Sharma, S.; Berman, L. E.; Hastings, J. B. & Hart, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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(Adsorption and diffusion of fluids in well-characterized adsorbent materials)

Description: This grant covers theoretical and molecular simulation studies in two areas: the thermodynamic behavior of associating liquids and their mixtures in the bulk phase, and the behavior of fluids in narrow pores. Fluids of longer chains are being simulated to test the perturbation theory. The Helmholtz free energy equation with the first order theory for association was applied to a wide variety of pure and mixed fluids; good agreement with experiment was found. In the second area, the nonlocal for… more
Date: January 1, 1991
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Adsorption of chromate/organic-acid mixtures in aquifer materials

Description: The overall objective of this project is to develop a fuller understanding of the interactions of mixtures of anionic co-contaminants with oxide-mineral surfaces. Our specific focus is on the competitive interactions of chromate and oxalic acid on ferric oxyhydroxide and on natural aquifer materials. Chromate and oxalate are of practical interest as widespread contaminants at many DOE facilities. However, these anions also are excellent model adsorbates for elucidating fundamental aspects of io… more
Date: July 15, 1991
Creator: Fish, W. & Palmer, C.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Adsorption of chromate/organic-acid mixtures in aquifer materials. Technical progress report, 1 July 1990--30 June 1991

Description: The overall objective of this project is to develop a fuller understanding of the interactions of mixtures of anionic co-contaminants with oxide-mineral surfaces. Our specific focus is on the competitive interactions of chromate and oxalic acid on ferric oxyhydroxide and on natural aquifer materials. Chromate and oxalate are of practical interest as widespread contaminants at many DOE facilities. However, these anions also are excellent model adsorbates for elucidating fundamental aspects of io… more
Date: July 15, 1991
Creator: Fish, W. & Palmer, C. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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