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Evidence of former higher temperatures from alteration minerals, Bostic 1-A well, Mountain Home, Idaho

Description: Cuttings from the silicic volcanics in the Bostic 1-A well near Mountain Home, Idaho have been examined petrographically with the assistance of x-ray diffraction and electron microprobe analyses. Results indicate that these rocks have been subjected to much higher temperatures than were observed in the well in 1974, when a static temperature log was run. It is not known to what extent the alternation may be due to greater depth of burial in the past, or whether it resulted from an early hydroth… more
Date: January 1, 1982
Creator: Arney, B.
Partner: UNT Libraries Government Documents Department
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Organic iodine removal from simulated dissolver off-gas streams using silver-exchanged mordenite

Description: The removal of methyl iodide by absorption onto silver mordenite was studied using a simulated off-gas from the fuel dissolution step of a nuclear fuel reprocessing plant. The methyl iodide absorption of silver mordenite was examined for the effects of NO/sub x/, humidity, iodine concentration, filter temperature, and filter pretreatment. The highest iodine loading achieved in these tests has been 34 mg CH/sub 3/I per g of substrate, approximately five times less than the elemental iodine loadi… more
Date: January 1, 1980
Creator: Jubin, R. T.
Partner: UNT Libraries Government Documents Department
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Massive sulfide deposits and hydrothermal solutions: incremental reaction modeling of mineral precipitation and sulfur isotopic evolution

Description: Incremental reaction path modeling of chemical and sulfur isotopic reactions occurring in active hydrothermal vents on the seafloor, in combination with chemical and petrographic data from sulfide samples from the seafloor and massive sulfide ore deposits, allows a detailed examination of the processes involved. This paper presents theoretical models of reactions of two types: (1) adiabatic mixing between hydrothermal solution and seawater, and (2) reaction of hydrothermal solution with sulfide… more
Date: January 1, 1986
Creator: Janecky, D.R.
Partner: UNT Libraries Government Documents Department
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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

Description: 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.
Partner: UNT Libraries Government Documents Department
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The use of synchrotron radiation for the analysis of coal combustion products

Description: An understanding of the chemical composition of such slags under boiler operating conditions and as function of the mineral composition of various coals is the ultimate goal of this program. The experiment involves scanning through the K- or L-shell absorption edge of the element in question. The structure of the absorption edge, consisting of transitions to unoccupied molecular levels, can be compared to those of model compounds for identification. The relative position of the absorption edge … more
Date: May 1, 1992
Creator: Manowitz, B. & Gordon, B.
Partner: UNT Libraries Government Documents Department
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Analysis of erosion and transport of carbon impurity in the TFTR inner bumper limiter region

Description: Carbon sputtering and transport on the TFTR inner graphite bumper limiter is investigated with the impurity transport code REDEP. Analysis is carried out for a series of ohmic discharges in TFTR. Predictions for Z{sub eff} in the core plasma agree well with in-situ experimental measurements. Run-away self-sputtering of carbon is predicted at low densities and high edge plasma temperatures when the limiter surface was purged of deuterium. Surface erosion and deposition is analyzed. In general, r… more
Date: January 1, 1992
Creator: Hua, T. Q. & Brooks, J. N.
Partner: UNT Libraries Government Documents Department
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International conference on bone mineral measurement, October 12--13, 1973, Chicago, Illinois

Description: From international conference on bone mineral measurement; Chicago, Illinois, USA (12 Oct 1973). Abstracts of papers presented at the international conference on bone mineral measurement are presented. The papers were grouped into two sessions: a physical session including papers on measuring techniques, errors, interpretation and correlations, dual photon techniques, and data handling and exchange; a biomedical session including papers on bone disease, osteoporosis, normative data, non-disease… more
Date: December 31, 1973
Partner: UNT Libraries Government Documents Department
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Damage to fused silica windows while under simultaneous exposure to flowing solvents and laser radiation and 308nm

Description: This paper reports the results of a study to determine the degrading effects of flowing dye solvents on the laser damage threshold of fused-silica windows at 308nm. Thresholds were measured at the SiO/sub 2/solvent interface in a test cell. Bare SiO/sub 2/ tested in air at 308nm (20ns) typically exhibits a threshold ranging from 4 to 10 Jcm/sup 2/; with the solvent cyclohexane in contact, a threshold as low as 0.3 Jcm/sup 2/ was measured. The damage data indicate that window lifetime (number of… more
Date: January 1, 1987
Creator: Mauro, B. R.; Foltyn, S. R. & Sanders, V. E.
Partner: UNT Libraries Government Documents Department
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Engineering considerations of the advanced free electron laser facility

Description: The Advanced Free-Electron Laser (AFEL) is being built at Los Alamos inside a large laboratory building. In addition to cost and available space considerations, several engineering issues affected the design of the AFEL and its facility. The 1300-MHz, 20-MeV electron linac required extensive radiation shielding and a short rf-waveguide run. Free-Electron Lasers (FEL) and photocathode-drive laser optics required a clean, constant temperature environment. New environmental, health, and safety (ES… more
Date: January 1, 1991
Creator: Meier, K.L.
Partner: UNT Libraries Government Documents Department
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Modified Murnaghan equation of state applied to shock compression of silica, basalt, and dolomite

Description: An equation of state previously used by the author is developed further and applied to geologic media. The equation is of the same form as the Murnaghan equation of state, but with the elastic constant terms replaced by the cohesive energy density (internal pressure), and the exponential term given as a sum of the Gruneisen parameter and the gaseous adiabatic exponent. Data for shock compression of silica, basalt, and dolomite are analyzed according to the equation.
Date: December 20, 1965
Creator: Rogers, L.A.
Partner: UNT Libraries Government Documents Department
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Synchrotron x-ray study of physisorbed films of mixtures of Ar and Xe on graphite

Description: Mixtures of Ar and Xe have been studied in most of the submonolayer region of the phase diagram (T,chi,rho), T = temperature, chi = chemical composition, rho = fraction of a monolayer. The basic feature is a large tendency to form ..sqrt.. 3 x ..sqrt.. 3 commensurate alloys (Kr-like structures), but none of the commensurate nor of the incommensurate structures form a chemically ordered alloy at 11 K. Thus the 2D solid can be thought of as a solid consisting of particles of an average size. This… more
Date: July 1, 1982
Creator: Bohr, J.; Nielsen, M.; McTague, J. P.; Als-Nielsen, J. & Kjaer, K.
Partner: UNT Libraries Government Documents Department
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Thermal strains in titanium aluminide and nickel aluminide composites

Description: Neutron diffraction was used to measure residual thermal strains developed during postfabrication cooling in titanium aluminide and nickel aluminide intermetallic matrix composites. Silicon carbide /Ti 14Al-21Nb, tungsten and sapphire/NiAl, and sapphire and SiC-coated sapphire/NiAl{sub 25}Fe{sub 10} composites were investigated. The thermal expansion coefficient of the matrix is usually greater than that of the fibers. As such, during cooldown, compressive residual strains are generated in the … more
Date: January 1, 1992
Creator: Saigal, A. (Tufts Univ., Medford, MA (United States). Dept. of Mechanical Engineering) & Kupperman, D.S. (Argonne National Lab., IL (United States))
Partner: UNT Libraries Government Documents Department
open access

Muon Spin-Rotation Study on Magnetite

Description: Muon spin-rotation (..mu..SR) results on synthetic single crystals of magnetite (Fe/sub 3/O/sub 4/) support the idea of muon bond formation in oxides. The anomaly in the temperature dependence of the ..mu..SR signal observed in Fe/sub 3/O/sub 4/ may be attributed to the existence of molecular polarons in the Verwey transition-temperature region.
Date: January 1, 1982
Creator: Boekema, C.; Brabers, V. A. M.; Denison, A. B.; Heffner, R. H.; Hutson, R. L.; Leon, M. et al.
Partner: UNT Libraries Government Documents Department
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Simulation experiments and solar wind sputtering

Description: In order to isolate the role played by solar wind sputtering from other lunar surface phenomena a number of simulation experiments were performed, including isotope abundance measurements of Ca sputtered from terrestrial fluorite and plagioclase by 50-keV and 130-keV /sup 14/N beams, measurement of the energy distribution of U atoms sputtered with 80-keV /sup 40/Ar, and measurement of the fraction of sputtered U atoms which stick on the surfaces used to collect these atoms. 10 references. (JFP)
Date: January 1, 1978
Creator: Griffith, J. E.; Papanastassiou, D. A.; Russell, W. A.; Tombrello, T. A. & Weller, R. A.
Partner: UNT Libraries Government Documents Department
open access

Prediction of limestone requirements for SO/sub 2/ emission control in atmospheric pressure fluidized-bed combustion

Description: The limestone-SO/sub 2/ reactivity as determined on a thermogravimetric analyzer was used to estimate the quantity of limestone required to meet the SO/sub 2/ emission standard in atmospheric fluidized-bed coal combustors. Comparison of laboratory TGA calcium utilization with pilot plant experimental results were made. Estimates of SO/sub 2/ retention in a carbon burnup cell were made for various limestone feed options. From this information, estimates of limestone requirements for an AFBC-CBC … more
Date: January 1, 1977
Creator: Snyder, R. B.; Wilson, W. I. & Johnson, I.
Partner: UNT Libraries Government Documents Department
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Geotechnical Properties of Sediments From North Pacific and Northern Bermuda Rise

Description: Studies of geotechnical properties for the Sub-seabed Disposal Program have been oriented toward sediment characterization related to effectiveness as a containment media and determination of detailed engineering behavior. Consolidation tests of the deeper samples in the North Pacific clays indicate that the sediment column is normally consolidated. The in-situ coefficient of permeability (k) within the cored depth of 25 meters is relatively constant at 10/sup -7/ cm/sec. Consolidated undrained… more
Date: January 1, 1980
Creator: Silva, A. J.; Laine, E. P.; Lipkin, J.; Heath, G. R. & Akers, S. A.
Partner: UNT Libraries Government Documents Department
open access

Organic iodine removal from simulated dissolver off-gas streams using partially exchanged silver mordenite

Description: The removal of methyl iodide by adsorption onto silver mordenite was studied using a simulated off-gas from the fuel dissolution step of a nuclear fuel reprocessing plant. The methyl iodide adsorption of partially exchanged silver mordenite was examined for the effects of NO/sub x/, humidity, filter temperature, and degree of silver exchange. Partially exchanged silver mordenite, in general, achieved significantly higher silver utilizations than the fully exchanged material. Silver utilizations… more
Date: January 1, 1982
Creator: Jubin, R. T.
Partner: UNT Libraries Government Documents Department
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DOE Task Force meeting on Electrical Breakdown of Insulating Ceramics in a High Radiation Field

Description: This volume contains the abstracts and presentation material from the Research Assistance Task Force Meeting Electrical Breakdown of Insulating Ceramics in a High-Radiation Field.'' The meeting was jointly sponsored by the Office of Basic Energy Sciences and the Office of Fusion Energy of the US Department of Energy in Vail, Colorado, May 28--June 1, 1991. The 26 participants represented expertise in fusion, radiation damage, electrical breakdown, ceramics, and semiconductor and electronic stru… more
Date: August 1, 1991
Creator: Green, P.H. (comp.)
Partner: UNT Libraries Government Documents Department
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Mine roof drill bits that save money

Description: Sandia National Laboratories, Albuquerque, NM, has developed advanced technology roof bolt drill bits which have demonstrated longer life, higher penetration rates at lower thrust and torque, and lower specific energy than conventional roof bolt drill bits. This is achieved through use of advanced technology cutting materials and novel bit body designs. These bits have received extensive laboratory and mine testing. Their performance has been evaluated and estimates of their value in reducing c… more
Date: April 1, 1982
Creator: Ford, L.M.
Partner: UNT Libraries Government Documents Department
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Migration of radionuclides following shallow land burial

Description: A study of radionuclide migration was conducted at a facility used from 1944 to 1949 for the shallow land burial of radwaste produced during operations with two reactors and related nuclear research. It is situated in glacial drift 45 m thick. Underlying the drift is a generally level Silurian dolomite bedrock 60 m thick. The thickness of the drift decreases as the surface slopes downhill (north) until the dolomite reaches the surface and forms the bed of a river, 700 m to the north. This study… more
Date: January 1, 1980
Creator: Sedlet, J. & Golchert, N.W.
Partner: UNT Libraries Government Documents Department
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Methane or methanol via catalytic gasification of biomass

Description: Methane and methanol synthesis gas can be produced by steam gasification of biomass in the presence of appropriate catalysts. A 5 cm diameter reactor has been used to determine the desired catalysts and operating temperature. A process development unit (PDU) has demonstrated steam gasification of biomass with catalysts at rates up to 35 kg per hour. Methane yields of 0.28 nm/sup 3/ per kg of dry wood were produced in the small laboratory reactor. Further methanation of the product gas mixture c… more
Date: March 1, 1980
Creator: Mitchell, D. H.; Mudge, L. K.; Robertus, R. J.; Weber, S. L. & Sealock, L. J. Jr.
Partner: UNT Libraries Government Documents Department
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The effects of specimen geometry and size on the fracture toughness of nuclear graphites

Description: In a joint Oak Ridge National Laboratory (ORNL)/Japan Atomic Energy Research Institute (JAERI) study, various fracture toughness techniques were applied to Toyo Tanso grade IG-110 graphite to establish if specimen geometry influences on fracture toughness. The test geometries investigated were: compact tension (CT), disc compact tension (DCT), short rod (SR), chevron-notched short-red (CNSR), cylindrical bend specimen (BS), and centrally slotted disc (CSD). Specimen geometries which allow slow … more
Date: January 1, 1991
Creator: Romanoski, G.R. & Burchell, T.D.
Partner: UNT Libraries Government Documents Department
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Effects of silica redistribution on performance of high-level nuclear waste repositories in saturated geologic formations

Description: Evaluation of the thermohydrological conditions near high-level waste packages is needed for the design of the waste canister and for overall repository design and performance assessment. Most available studies in this area have assumed that the hydrologic properties of the host rock do not change in response to the thermal, mechanical or chemical effects caused by waste emplacement. However, the ramifications of this simplifying assumption have not been substantiated. We have studied dissoluti… more
Date: November 1, 1985
Creator: Verma, A. & Pruess, K.
Partner: UNT Libraries Government Documents Department
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