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Low temperature, sulfur tolerant homogeneous catalysts for the water-gas shift reaction

Description: The purpose of this report is to update and reorganize our recent review on homogeneous catalysis of the water-gas shift reaction (WGSR) based on recent literature publications and patents. This updated version will serve as a means of selecting 10 candidate catalyst systems for use in developing effective, sulfur-tolerant, low temperature WGSR catalysts. This report discusses the variations possible in the basic chemistry associated with WGSR catalytic cycles, including basic, acidic, and neut… more
Date: January 20, 1986
Creator: Laine, R. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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/sup 238/Pu fuel-form processes. Quarterly report, October-December 1981

Description: Progress in the Savannah River /sup 238/Pu Fuel Form Program is summarized. Work during this period concentrated on the extensive cracking of the /sup 238/PuO/sub 2/ fuel form prior to encapsulation in the iridium containment shell for heat sources. This cracking results in increased recycle cost and decreased production efficiency. To better understand this cracking, Savannah River Laboratory (SRL) has made an extensive review of the development of /sup 238/PuO/sub 2/ fuel forms from small-sca… more
Date: May 1, 1982
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ir/PuO/sub 2/ compatibility: transfer of impurities from plutonium dioxide to iridium metal during high temperature aging

Description: Plutonium oxide fuel pellets for powering radioisotopic thermoelectric generators for NASA space vehicles are encapsulated in iridium which has been grain-boundary-stabilized with thorium and aluminum. After aging for 6 months at 1310/sup 0/C under vacuum, enhanced grain growth is observed in the near-surface grains of the iridium next to the PuO/sub 2/. Examination of the grain boundaries by AES and SIMS shows a depletion of thorium and aluminum. Iron, chromium, and nickel from the fuel were f… more
Date: January 1, 1984
Creator: Taylor, D. H.; Christie, W. H. & Pavone, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Flight-systems safety program. Progress report, February 1982

Description: This technical monthly report covers studies related to the use of /sup 238/PuO/sub 2/ in radioisotope power systems carried out for the Office of Coordination and Special Projects of the US Department of Energy by los Alamos National Laboratory. Most of the studies discussed here are ongoing. Results and conclusions described may change as the work continues. Published reference of the results cited in this report should not be made without the explicit permission of the person in charge of th… more
Date: February 1, 1982
Creator: Bronisz, S. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Radiochemistry of Iridium

Description: The general and analytical chemistry of Ir are reviewed and applications to the radiochemistry of Ir are discussed. Topics covered include dissolution of samples containing Ir, counting techniques for radioactive Ir isotopes, radiochemical procedures for Ir radionuclides, and safety practices. A list is included of the radioactive nuclides of Ir. 106 references. (C.H.)
Date: October 1961
Creator: Leddicotte, G. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quality engineering and control. Semiannual progress report, November-December 1978, January-April 1979. [PCB]

Description: This document reports the following: atomic absorption spectroscopy of Ir in Pu-Ir alloys; removal of Pu from soil; surface microanalysis using elemental x-ray mapping; microscopic scanning of Ga in Pu; microscopy of defects in Pu; emission spectroscopy of Ir and Y in PuO/sub 2/; gas chromatograhy of PCB's in transformer oils and water; liquid chromatography of chlorophenoxy acid herbicides in water; solution analysis by spark source mass spectrometry; a portable gas sampling system; flamm… more
Date: August 2, 1980
Creator: Carpenter, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Versatile electrochemical microsensors for environmental monitoring

Description: The fabrication of novel multielement microelectrode array sensors is reported. With regard to individual array elements, two main concepts are pursued. One involves the use of relatively non-selective microelectrode elements, coupled with pattern recognition methods, for data analysis. This strategy is most applicable when prior knowledge about the chemical environment is limited, or when mainly qualitative information is sought. The second concept involves the development of arrays containing… more
Date: October 1, 1991
Creator: Glass, R.S.; Hong, K.C. (Lawrence Livermore National Lab., CA (United States). Chemistry and Materials Science Dept.); Ashley, K. (San Jose State Univ., CA (United States). Dept. of Chemistry) & Granstaff, V.E. (Sandia National Labs., Albuquerque, NM (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Flight-Systems Safety Program, April 1982. Progress report

Description: This technical monthly report covers studies related to the use of /sup 238/PuO/sub 2/ in radioisotope power systems carried out for the Office of Coordination and Special Projects of the US Department of Energy by Los Alamos National Laboratory. Most of the studies discussed here are ongoing. Results and conclusions described may change as the work continues. Published reference of the results cited in this report should not be made without the explicit permission of the person in charge of th… more
Date: July 1, 1982
Creator: Bronisz, S. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mixed Alcohol Synthesis Catalyst Screening 2007 Progress Report

Description: Pacific Northwest National Laboratory (PNNL) and National Renewable Energy Laboratory (NREL) are researching the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). PNNL is obtaining commercially available mixed alcohol or preparing promising mixed-alcohol catalysts and screening them in a laboratory-scale reactor system. The most promising catalysts are provided to NREL for testing using a slipstream from a pilot-scale biomass gasifier. After a review of the li… more
Date: November 1, 2007
Creator: Gerber, Mark A.; White, J. F.; Gray, Michel J. & Stevens, Don J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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COMPUTER SIMULATION OP FRANK LOOP CONTRAST IN FIELD IONIMAGES

Description: A computer model for simulation of the image contrast caused by Frank dislocation loops in field ion tips of fcc materials is presented. The model is based on the shell model for ion image simulation, whereas the displacement field of Frank loops is computed from the exact displacement equation for a closed dislocation loop in an isotropically elastic continuum. A method for taking surface effects into account by superposition of the displacement field of an image loop is introduced. The result… more
Date: September 1, 1973
Creator: Stolt, Kaj Gunnar
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Consumable arc-melting, extruding, and rolling process for iridium sheet

Description: An iridium alloy has been used as cladding for the /sup 238/PuO/sub 2/ fuel in radioisotope thermoelectric generators (RTGs) for recent interplanetary spacecraft such as Voyagers 1 and 2 and will be used for the Galileo and Ulysses spacecraft. The iridium alloy sheet for the fuel cladding used on these missions was fabricated by hot and cold rolling of arc-melted and drop-cast 0.5-kg ingots. Upon completion of production for these spacecraft, an opportunity was taken to conduct process improvem… more
Date: June 1, 1986
Creator: Heestand, R. L.; Copeland, G. L. & Martin, M. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Iridium abundance measurements across bio-event horizons in the fossil record

Description: Geochemical measurements have been performed on thousands of rock samples collected across bio-event horizons using Instrumental Neutron Activation Analysis (INAA) for about 40 common and trace elements and radiochemical isolation procedures for Ir. On selected samples, Os, Pt and Au were also radiochemically determined. These studies have encompassed the time interval from the Precambrian-Cambrian transition to the Late Eocene impact (microspherule) horizons. Our early work strengthened the Al… more
Date: January 1, 1989
Creator: Orth, C.J.; Attrep, M. Jr. & Quintana, L.R. (Los Alamos National Lab., NM (USA))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experiments with powdered CMN thermometers between 10 mK and 4K, and a comparison with an NBS SRM 768 fixed-point device

Description: Comparison of a powdered CMN thermometer with an NBS fixed point device demonstrates an internal inconsistency in the T/sub c/'s assigned to the fixed point device. T/sub c/'s between 100 and 200 mK are in excellent agreement with a temperature scale interpolated between He vapor pressure temperatures and nuclear orientation temperatures, but there is a discrepancy of 8% at the 15 mK point. Evidence for different susceptibility-temperature relations for superficially similar CMN thermometers is… more
Date: August 1, 1981
Creator: Fogle, W. E.; Hornung, E. W.; Mayberry, M. C. & Phillips, N. E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Geochemical anomalies near the Eocene-Oligocene and Permian-Triassic boundaries

Description: Evidence is presented to support the theory that several mass extinctions, i.e., those that define the Permian-Triassic boundary, the Cretaceous-Tertiary boundary, and the Eocene-1 Oligocene boundary, were caused by impact on the earth of extraterrestrial objects having the composition of carbonaceous chondrites and diameters of about 10 km. The evidence consists of anomalously high concentrations of iridium and other siderophile elements at the stratigraphic levels defining the extinctions. (A… more
Date: October 1, 1981
Creator: Asaro, F.; Alvarez, L.W.; Alvarez, W. & Michel, H.V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance of oblique angle of incidence collection systems in the VUV

Description: High rejection filters are difficult enough to achieve in the UV-VIS-IR with known materials and constants. Even more difficult is the design and manufacture of rejection filters in the EUV and VUV given the uncertainty of optical constants and their wide variation over this spectral range. We have begun work to characterize materials from 584 A to 1300 A to verify reported optical constants, in order to design and realize the optimum collection system. 8 refs., 2 figs., 8 tabs.
Date: January 1, 1986
Creator: Keller, G.L.; Scott, M.L. & Mitchell, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Detection and sizing of underbead cracks using ultrasonic nondestructive examination

Description: Ultrasonic nondestructive examination (NDE) will detect three mil deep underbead cracks in welds joining thin walled iridium hemishells. A correlation was developed to relate the amplitude of the signal reflected from the crack with crack wall area. The observed cracks occur in the weld underbead in the arc taper area during encapsulation of /sup 238/PuO/sub 2/ pellets for thermoelectric generators used in deep space exploration.
Date: February 11, 1982
Creator: Scarbrough, J.D. & Wierzbicki, W.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Method for high temperature mercury capture from gas streams

Description: A process to facilitate mercury extraction from high temperature flue/fuel gas via the use of metal sorbents which capture mercury at ambient and high temperatures. The spent sorbents can be regenerated after exposure to mercury. The metal sorbents can be used as pure metals (or combinations of metals) or dispersed on an inert support to increase surface area per gram of metal sorbent. Iridium and ruthenium are effective for mercury removal from flue and smelter gases. Palladium and platinum ar… more
Date: April 25, 2006
Creator: Granite, E. J. & Pennline, H. W.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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High Strain Rate Tensile Testing of DOP-26 Iridium

Description: The iridium alloy DOP-26 was developed through the Radioisotope Power Systems Program in the Office of Nuclear Energy of the Department of Energy. It is used for clad vent set cups containing radioactive fuel in radioisotope thermoelectric generator (RTG) heat sources which provide electric power for spacecraft. This report describes mechanical testing results for DOP-26. Specimens were given a vacuum recrystallization anneal of 1 hour at 1375 C and tested in tension in orientations parallel an… more
Date: November 1, 2007
Creator: Schneibel, Joachim H; Carmichael Jr, Cecil Albert & George, Easo P
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evidence for an extraterrestrial impact 12,900 years ago that contributed to the megafaunal extinctions and the Younger Dryas cooling

Description: A carbon-rich black layer, dating to ~;;12.9 ka, has been previously identified at ~;;50 Clovis-age sites across North America and appears contemporaneous with the abrupt onset of Younger Dryas (YD) cooling. The in situ bones of extinct Pleistocene megafauna, along with Clovis tool assemblages, occur below this black layer but not within or above it. Causes for the extinctions, YD cooling, and termination of Clovis culture have long been controversial. In this paper, we provide evidence for an … more
Date: March 13, 2007
Creator: Firestone, Richard B.; Firestone, R. B.; West, A.; Kennett, J. P.; Becker, L.; Bunch, T. E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Space Nuclear Safety Program. Progress report, April 1984

Description: This technical monthly report covers studies related to the use of /sup 238/PuO/sub 2/ in radioisotope power systems carried out for the Office of Special Nuclear Projects of the US Department of Energy by Los Alamos National Laboratory. Covered are: general-purpose heat source testing and recovery, and safety technology program (biaxial testing, iridium chemistry).
Date: October 1, 1985
Creator: George, T.G. (comp.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Impact failure of MHW fuel sphere MHFT 65: report on interagency task force investigation and SRL evaluation of failure, November 1979-February 1980

Description: Following a safety verification impact test failure of a Multi-Hundred Watt (MHW) fuel sphere made at Savannah River Plant, from which 2.1 g of /sup 238/PuO/sub 2/ escaped containment, the Department of Energy organized a task force to investigate the cause of the test failure and to assess the failure probability of MHW fuel made at SRP. The task force described a two-part failure mechanism: embrittlement of the iridium containment shell by phosphorus which may have been picked up from the fue… more
Date: June 1, 1981
Creator: Taylor, D. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Forming of metal components for radioisotope heat sources

Description: Flight-quality iridium components can be fabricated from iridium alloys by modifying standard production processes. A large quantity of metrological and NDE data support the quality of these devices, which, in turn, justify their use in containing plutonium fuel for space system applications.
Date: January 1, 1984
Creator: Johnson, E. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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