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Healing of Fast-Neutron-Induced Changes in Graphite. II. The Effect of Heating During Exposure, Interim Report on Problem 323 MLC 2301

Description: Technical report. The effect of temperature during pile exposure on the fast-neutron-induced change in properties of graphite was studied. Temperatures up to 125 degrees C have no effect upon the rate of increase of elastic modulus; pieces exposed at 300 degrees C on the other hand show no change at all in elastic modulus. The increase in electrical resistance s an inverse function of the temperature of exposure at all temperatures in the range 60 to 300 degrees C.
Date: July 10, 1944
Creator: Neubert, Thomas A.; Novick, A.; Schenck, R. & Shapiro, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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PROCEEDINGS OF THE FRENCH-AMERICAN CONFERENCE ON GRAPHITE REACTORS, HELD AT BROOKHAVEN NATIONAL LABORATORY , NOVEMBER 12 TO 15, 1957

Description: Twenty-eight of the thirty-five papers presented at the conference are included with discussions. Abstracts of the remaining seven papers are given. The seven sessions were devoted to: radiation effects on graphite, nuclear properties of graphitc, graphite lattice reactivities, chemistry of graphite, chemical reactions between liquid Na and Zr, slug canning fer the ORNL Graphite Reactor, and critical assemblies. Separate abstracts have been prepared for each of the twentyeight papers. (T.R.H.)
Date: October 31, 1959
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Friction studies of graphite and mixtures of graphite with several metallic oxides and salts at temperatures to 1000 degrees F

Description: Report presenting an experimental friction study using graphite and mixtures of graphite with lead oxide, cadmium oxide, sodium sulfate, or cadmium sulfate as solid lubricants. Runs were made at temperatures up to 1000 degrees Fahrenheit with various steel and Inconel combinations.
Date: February 1956
Creator: Peterson, Marshall B. & Johnson, Robert L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final Report : Production Test 105-329-F, Filled Block Graphite Sample Report

Description: This report provides data on production test 105-329-P and solid graphite samples used to analyze damage obtained from controlled natural erosion tests. The data provided will help establish current ideas on the status of filler block graphite and interpretation of the data will assist in establishing pile operating temperature limits based on stored energy.
Date: November 1, 1950
Creator: Johnson, P. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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GRAPHITE-MODERATED, GRAPHITE-REFLECTED CRITICAL ASSEMBLIES

Description: Graphite-moderated, graphite reflected critical assemblies have been set up in the LASL Honeycomb remotely controlled machine. lnformation has been obtained on the critical masses of systems having C/Oy ratios of 6650 and 4093. A third system at a smaller ratio is planned. The reactivity contribution of channels through the core and reflector was determined. (auth)
Date: January 1, 1957
Creator: Byers, Cleo C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of Graphite Bodies : Progress Report No. 3 for the Period March 1, 1959 to May 31, 1959

Description: This document is the third in a series of progress report that records investigations of graphite bodies. Along with the report, two appendices are given to describe the different graphite bodies: "Synthetic Binders for Carbon and Graphite" and "High Temperature Physical Properties of Molded Graphites".
Date: June 10, 1959
Creator: Bradstreet, Samuel W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Great Lakes Carbon Corporation Research and Development Division Quarterly Report: January-March 1952

Description: The following quarterly report is the third in a series that discusses the investigation on the production of purified graphite through the use of self-purifying raw materials, covering the period of January, February and March of 1952.
Date: 1956
Creator: Great Lakes Carbon Corporation. Research and Development Division.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Effect of Neutron Bombardment on the Specific Heat of Graphite at Low Temperatures

Description: The work described in this technical report was undertaken as part of a larger program dealing with a systematic investigation of changes in the physical prosperities of artificial graphite due to neutron bombardment. Very pronounced among those changes is the increase in the elastic modulus. Since there is a general relationship between the elastic modulus of a given substance and its specific heat, it was expected that corresponding changes will occur in the specific heat. In conclusion, th… more
Date: September 5, 1945
Creator: Estermann, I. (Immanuel), 1900-1973 & Kirkland, G. I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Healing of Fast-Neutron-Induced Changes in Graphite. III. Further Experiments on Effect of Heating During Exposure

Description: Abstract. It has been established that heating samples of graphite during exposure in a pile decreases substantially the observed changes in the elastic modulus and electrical resistance caused by the irradiation. The functional relationship between the percentage changes observed and the temperature of exposure resembles the relationship between the final percentage changes and the temperature of heat treatment after exposure (cf. report CC-1668). Anomalous results reported previously for hi… more
Date: March 3, 1945
Creator: Neubert, T. J.; Novick, A.; Schenek, R. T.; Shapiro, E. & Van Dyken, A. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Massive Neutron Exposure on the Distortion of Reactor Graphite

Description: Distortion of reactor-grade graphites was studied at varying neutron exposures ranging up to 14 x 10/sup 21/ neutrons per cm/sup 2/ (nvt)/sup */ at temperatures of irradiation ranging from 425 to 800 deg C. This exposure level corresponds to approximately 100,000 megawatt days per adjacent ton of fuel (Mwd/ At) in a graphite-moderated reactor. A conventionalcoke graphite, CSF, and two needle-coke graphites, NC-7 and NC-8, were studied. At all temperatures of irradiation the contraction rate of … more
Date: May 28, 1963
Creator: Helm, J. W. & Davidson, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Graphite Isotope Ratio Method: A Primer on Estimating Plutonium Production in Graphite Moderated Reactors

Description: The Graphite Isotope Ratio Method (GIRM) is a technique used to estimate the total plutonium production in a graphite-moderated reactor. The cumulative plutonium production in that reactor can be accurately determined by measuring neutron irradiation induced isotopic ratio changes in certain impurity elements within the graphite moderator. The method does not require detailed knowledge of a reactor's operating history, although that knowledge can decrease the uncertainty of the production estim… more
Date: March 25, 2004
Creator: Gesh, Christopher J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Statistical Comparison of the Baseline Mechanical Properties of NBG-18 and PCEA Graphite

Description: High-purity graphite is the core structural material of choice in the Very High Temperature Reactor (VHTR), a graphite-moderated, helium-cooled design that is capable of producing process heat for power generation and for industrial process that require temperatures higher than the outlet temperatures of present nuclear reactors. The Baseline Graphite Characterization Program is endeavoring to minimize the conservative estimates of as-manufactured mechanical and physical properties by providing… more
Date: August 1, 2013
Creator: Carroll, Mark C. & Rohrbaugh, David T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Possible Diamond-Like Nanoscale Structures Induced by Slow Highly-Charged Ions on Graphite (HOPG)

Description: The interaction between slow highly-charged ions (SHCI) of different charge states from an electron-beam ion trap and highly oriented pyrolytic graphite (HOPG) surfaces is studied in terms of modification of electronic states at single-ion impact nanosizeareas. Results are presented from AFM/STM analysis of the induced-surface topological features combined with Raman spectroscopy. I-V characteristics for a number of different impact regions were measured with STM and the results argue for possi… more
Date: January 6, 2009
Creator: Sideras-Haddad, E.; Schenkel, T.; Shrivastava, S.; Makgato, T.; Batra, A.; Weis, C. D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Graphite oxidation modeling for application in MELCOR.

Description: The Arrhenius parameters for graphite oxidation in air are reviewed and compared. One-dimensional models of graphite oxidation coupled with mass transfer of oxidant are presented in dimensionless form for rectangular and spherical geometries. A single dimensionless group is shown to encapsulate the coupled phenomena, and is used to determine the effective reaction rate when mass transfer can impede the oxidation process. For integer reaction order kinetics, analytical expressions are presented … more
Date: January 1, 2009
Creator: Gelbard, Fred
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Graphite Problems in Air-Cooled Reactors

Description: This report discusses problems affecting the long-term use of graphite in air-cooled reactors. The report identifies these problems as oxidation, radiation induced dimensional expansions and accumulation of stored energy. The report finds that "frequent low temperature annealing eliminates these problems and may extend the lifetime of the graphite indefinitely." (From abstract)
Date: 1962
Creator: Schweitzer, D. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of Porosity Development in Oxidized Graphite using Automated Image Analysis Techniques

Description: This document reports on initial activities at ORNL aimed at quantitative characterization of porosity development in oxidized graphite specimens using automated image analysis (AIA) techniques. A series of cylindrical shape specimens were machined from nuclear-grade graphite (type PCEA, from GrafTech International). The specimens were oxidized in air to various levels of weight loss (between 5 and 20 %) and at three oxidation temperatures (between 600 and 750 oC). The procedure used for specim… more
Date: September 1, 2009
Creator: Contescu, Cristian I & Burchell, Timothy D
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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