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Development of Fueled Graphite Containing Pyrolytic-Carbon Coated Carbide Particles for Nonpurged, Gas-Cooled Reactor Systems

Description: Abstract: Progress is reported in several areas of development of fueled graphite containing coated particles for nonurged gas-cooled reactor systems. The sol-gel process has been modified for making spherical particles of both thorium-uranium carbide and thorium-uranium oxide suitable for coating. Equipment has been assembled and methods have been developed for deposition of pyrolytic-carbon coating under well-controlled conditions. Damage to coated particles during fabrication into a graphi… more
Date: November 1963
Creator: Carlsen, F. L., Jr.; Bomar, E. S. & Harms, W. O.
Partner: UNT Libraries Government Documents Department
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Scanning tunneling microscopy and atomic force microscopy of Au implanted in highly ordered pyrolytic graphite

Description: Surfaces of highly oriented pyrolytic graphite implanted with gold were studied by both constant current STM, constant force, and tapping mode AFM. Gold colloids were observed by both constant current STM and tapping mode AFM. The surfaces can be modified by applying currents of {plus_minus}4 V and 1 nA. In addition, pyramidal and faceted structures were observed on sample surfaces suggesting the presence of diamond microcrystals.
Date: January 1, 1996
Creator: Tung, Y.S.; Ueda, A.; Henderson, D.O.; Mu, R.; Gu, Z.; White, C.W. et al.
Partner: UNT Libraries Government Documents Department
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Raman spectroscopy of C-irradiated graphite

Description: Highly oriented pyrolytic graphite samples were irradiated with C{sup +} ions at 35 keV in a direction normal to the basal plane and subsequently annealed up to 1373 K. Substantial surface topography changes were observed at fluences of 5 {times} 10{sup 18} ions/m{sup 2} and higher using scanning electron and atomic force microscopies. Intricate networks of surface cracks and ridges developed after high dose implantation. A systematic study of the irradiation effects was conducted using Raman s… more
Date: September 1, 1994
Creator: Hembree, D. M. Jr.; Pedraza, D. F.; Romanoski, G. R.; Withrow, S. P. & Annis, B. K.
Partner: UNT Libraries Government Documents Department
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Accelerator-Based Irradiation Creep of Pyrolytic Carbon Used in TRISO Fuel Particles for the (VHTR) Very Hight Temperature Reactors

Description: Pyrolytic carbon (PyC) is one of the important structural materials in the TRISO fuel particles which will be used in the next generation of gas-cooled very-high-temperature reactors (VHTR). When the TRISO particles are under irradiation at high temperatures, creep of the PyC layers may cause radial cracking leading to catastrophic particle failure. Therefore, a fundamental understanding of the creep behavior of PyC during irradiation is required to predict the overall fuel performance.
Date: July 30, 2010
Creator: Wang, Lumin & Was, Gary
Partner: UNT Libraries Government Documents Department
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Comparison of the electrochemical properties of several commercial graphites with a templated disordered carbon

Description: A templated carbon was prepared by the pyrolysis of pyrene impregnated into pillared clay (PILC). The electrochemical performance of this was evaluated with the goal of using this material as an anode in Li-ion cells. The reversible capacity was measured as a function of C rate and the cycling characteristics were determined for various intercalation protocols. The performance of this material was compared to that of several commercial graphites tested under the same conditions. The PILC carbon… more
Date: April 11, 2000
Creator: Guidotti, R. A.; Reinhardt, F. W. & Sandi, G.
Partner: UNT Libraries Government Documents Department
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TRISO-Fuel Element Performance Modeling for the Hybrid LIFE Engine with Pu Fuel Blanket

Description: A TRISO-coated fuel thermo-mechanical performance study is performed for the hybrid LIFE engine to test the viability of TRISO particles to achieve ultra-high burnup of a weapons-grade Pu blanket. Our methodology includes full elastic anisotropy, time and temperature varying material properties for all TRISO layers, and a procedure to remap the elastic solutions in order to achieve fast fluences up to 30 x 10{sup 25} n {center_dot} m{sup -2} (E > 0.18 MeV). In order to model fast fluences in… more
Date: February 18, 2010
Creator: DeMange, P.; Marian, J.; Caro, M. & Caro, A.
Partner: UNT Libraries Government Documents Department
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Multilayered nuclear fuel element

Description: A nuclear fuel element is described which is suitable for high temperature applications comprised of a kernel of fissile material overlaid with concentric layers of impervious graphite, vitreous carbon, pyrolytic carbon and metal carbide. The kernel of fissile material is surrounded by a layer of impervious graphite. The layer of impervious graphite is then surrounded by a layer of vitreous carbon. Finally, an outer shell which includes alternating layers of pyrolytic carbon and metal carbide s… more
Date: December 1, 1996
Creator: Schweitzer, Donald G. & Sastre, Cesar
Partner: UNT Libraries Government Documents Department
open access

Comparison of the electrochemical properties of several commercial graphites with a templated disordered carbon

Description: A templated carbon was prepared by the pyrolysis of pyrene impregnated into pillared clay (PILC). The electrochemical performance of this was evaluated with the goal of using this material as an anode in Li-ion cells. The reversible capacity was measured as a function of C rate and the cycling characteristics were determined for various intercalation protocols. The performance of this material was compared to that of several commercial graphites tested under the same conditions. The PILC carbon… more
Date: March 22, 2000
Creator: GUIDOTTI,RONALD A.; REINHARDT,FREDERICK W. & SANDI,GISELLE
Partner: UNT Libraries Government Documents Department
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Recovery of Technetium and Iodine from Spent ATW TRISO Type Fuels.

Description: The Accelerator Transmutation of Waste (ATW) program is being developed to determine the feasibility of separating and transmutating the transactinides (Pu-Cm) and long-lived fission product (99Tc and 129I) from spent LWR fuel. Several types of ATW fuels have been suggested to transmutate the Pu-Cm fraction including TRISO type fuels. An ATW TRISO fuel would consist of a Pu-Cm oxide kernel surrounded by several layers of pyrolytic carbon, a layer of SiC, and an outer layer of pyrolytic carbon. … more
Date: January 1, 2001
Creator: Schroeder, N. C. (Norman C.) & Attrep, Moses
Partner: UNT Libraries Government Documents Department
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The optical constants and spectral specular reflectivity of highly oriented pyrolytic graphite (HOPG). Revision 1

Description: Measurements of the specular reflectivity and the optical constants of highly ordered pyrolytic graphite (HOPG) have been made using two independent optical systems. The first measures reflectance (at 1.06 {mu}m and 293 K) by comparing the intensity of a laser beam before and after reflecting off the sample. The second determines the complex index of raft-action (from 0.55 to 8.45 {mu}m, with sample temperatures of 293, 480, 900 and 1300 K) by ellipsometry. Agreement between the two methods is … more
Date: August 1, 1993
Creator: Havstad, M. A.; Schildbach, M. A. & McLean, W., II
Partner: UNT Libraries Government Documents Department
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Novel carbonaceous materials for lithium secondary batteries

Description: Carbonaceous materials have been synthesized using pillared clays (PILCs) as templates. The PILC was loaded with organic materials such as pyrene in the liquid and vapor phase, styrene in the vapor phase, trioxane, ethylene and propylene. The samples were then pyrolyzed at 700 C in an inert atmosphere, followed by dissolution of the inorganic template by conventional demineralization methods. X-ray powder diffraction of the carbons showed broad d{sub 002} peaks in the diffraction pattern, indic… more
Date: July 1, 1997
Creator: Sandi, G.; Winans, R. E.; Carrado, K. A. & Johnson, C. S.
Partner: UNT Libraries Government Documents Department
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Carbon based prosthetic devices

Description: This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project objective was to evaluate the use of carbon/carbon-fiber-reinforced composites for use in endoprosthetic devices. The application of these materials for the metacarpophalangeal (MP) joints of the hand was investigated. Issues concerning mechanical properties, bone fixation, biocompatibility, and wear are discussed. A system consisting of f… more
Date: December 31, 1998
Creator: Devlin, D.J.; Carroll, D.W.; Barbero, R.S.; Archuleta, T.; Klawitter, J.J.; Ogilvie, W. et al.
Partner: UNT Libraries Government Documents Department
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Results from ORNL Characterization of HRB-21 Reference Fuel

Description: This document is a compilation of the characterization data produced by ORNL for coated UCO fuel particles (350 {micro}m kernel diameter) fabricated by GA for the HRB-21 irradiation test capsule. The archived fuel particles form the batch used in HRB-21 were obtained by the Advanced Gas Reactor Fuel Development and Qualification (AGR) program for use as a reference material. The GA characterization data for this batch of fuel particles is presented in document GT-HTGR-88357, Rev. C, 'Capsule HR… more
Date: August 1, 2004
Creator: Hunn, John D
Partner: UNT Libraries Government Documents Department
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Compatibility/Stability Issues in the Use of Nitride Kernels in LWR TRISO Fuel

Description: The stability of the SiC layer in the presence of free nitrogen will be dependent upon the operating temperatures and resulting nitrogen pressures whether it is at High Temperature Gas-Cooled Reactor (HTGR) temperatures of 1000-1400 C (coolant design dependent) or LWR temperatures that range from 500-700 C. Although nitrogen released in fissioning will form fission product nitrides, there will remain an overpressure of nitrogen of some magnitude. The nitrogen can be speculated to transport thro… more
Date: February 1, 2012
Creator: Armstrong, Beth L & Besmann, Theodore M
Partner: UNT Libraries Government Documents Department
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INERI-2006-003-F FY07 Annual Report

Description: Project Title: Comparison of Characterization Methods for Anisotropy and Microstructure of TRISO Particle Layers This INERI was created to support a comparative study between the newly developed two modulator generalized ellipsometry microscope (2-MGEM) at the Oak Ridge National Laboratory (ORNL) and the more traditional optical polarimeter (RAPAX) at the Commissariat l' nergie Atomique (CEA). These two systems are used to measure the anisotropy of the pyrocarbon layers in tri-isotropic (TRISO)… more
Date: October 1, 2007
Creator: Hunn, John D
Partner: UNT Libraries Government Documents Department
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Data Compilation for AGR-1 Variant 3 Coated Particle Composite LEU01-49T

Description: This document is a compilation of characterization data for the AGR-1 variant 3 coated particle composite LEU01-49T, a composite of three batches of TRISO-coated 350 {micro}m diameter 19.7% low enrichment uranium oxide/uranium carbide kernels (LEUCO). The AGR-1 TRISO-coated particles consist of a spherical kernel coated with a {approx} 50% dense carbon buffer layer (100 {micro}m nominal thickness) followed by a dense inner pyrocarbon layer (40 {micro}m nominal thickness) followed by a SiC layer… more
Date: July 1, 2006
Creator: Hunn, John D & Lowden, Richard Andrew
Partner: UNT Libraries Government Documents Department
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Sound velocity of carbon at high pressures

Description: We have measured the sound velocity in shock compressed graphite. The data are consistent with a model of solid diamond from 0.8 to 1.4 Mbar. 18 references.
Date: September 11, 1984
Creator: Shaner, J. W.; Brown, J. M.; Swenson, C. A. & McQueen, R. G.
Partner: UNT Libraries Government Documents Department
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Data Compilation for AGR-1 Variant 3 Compact Lot LEU01-49T-Z

Description: This document is a compilation of characterization data for the AGR-1 vriant 3 fuel compact lot LEU01-49T-Z. The compacts were produced by ORNL for the Advanced Gas Reactor Fuel Development and Qualification (AGR) program for the first AGR irradiation test train (AGR-1). This compact lot was fabricated using particle composite LEU01-49T, which was a composite of three batches of TRISO-coated 350 {micro}m diameter 19.7% low enrichment uranium oxide/uranium carbide kernels (LEUCO). The AGR-1 TRIS… more
Date: August 1, 2006
Creator: Hunn, John D; Montgomery, Fred C & Pappano, Peter J
Partner: UNT Libraries Government Documents Department
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Data Compilation for AGR-3/4 Driver Particle Composite LEU03-09T

Description: This document is a compilation of characterization data for the AGR-3/4 driver fuel coated particle composite LEU03-09T, a composite of four batches of TRISO-coated, nominally 350 {micro}m diameter, 19.7% low enrichment uranium oxide/uranium carbide kernels (LEUCO). The AGR-3/4 driver fuel particles were fabricated using the AGR-1 baseline coating conditions and consist of a spherical kernel coated with an {approx}50% dense carbon buffer layer (100 {micro}m nominal thickness) followed by a dens… more
Date: March 1, 2007
Creator: Hunn, John D & Lowden, Richard Andrew
Partner: UNT Libraries Government Documents Department
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Thermophysical properties: some experience in research, development and applications

Description: Accurate measurements of thermophysical properties, understanding exactly any use requirements, and understanding the behavior of the material are all potential ingredients for in-depth research and development projects. The work reported here is but a brief description of some of the many LASL and SLA projects and their chain-branching manifestations.
Date: January 1, 1977
Creator: Wagner, P. & Acton, R. U.
Partner: UNT Libraries Government Documents Department
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Shock compression of pyrolytic, ceylon natural, and a hot-pressed synthetic graphite to 120 GPa

Description: Recent improvements have made the two-stage, light-gas gun at Lawrence Livermore Laboratory into a dependable source of very energetic planar shocks. Also, the inclined-prism technique has proved useful in observing anomalous behavior of materials, especially at low pressure. The availability of these improved techniques presented an opportunity to re-examine the low pressure, shock-compression characteristics for graphite and, in a search for an additional transformation, to extend some of the… more
Date: June 6, 1977
Creator: Gust, W. H. & Young, D. A.
Partner: UNT Libraries Government Documents Department
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Effects of deposition conditions on the properties of pyrolytic carbon deposited in a fluidized bed

Description: The high-density, isotropic pyrolytic carbon layer beneath the silicon carbide (IPyC) plays a key role in the irradiation performance of coated particle fuel. The IPyC layer protects the kernel from reactions with chlorine during deposition of the SiC layer, provides structural support for the SiC layer, and protects the SiC from fission products and carbon monoxide. The process conditions used by the Germans to deposit the IPyC coating produced a highly isotropic, but somewhat permeable IPyC c… more
Date: September 1, 2005
Creator: Lowden, Richard Andrew; Hunn, John D; Nunn, Stephen D; Kercher, Andrew K; Price, Jeffery R & Jellison Jr, Gerald Earle
Partner: UNT Libraries Government Documents Department
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