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Fabrication and characterization of MCC approved testing material: ATM-11 glass

Description: ATM-11 glass is designed to be representative of defense high-level waste glasses that will be produced by the Defense Waste Processing Facility at the Savannah River Plant in Aiken, South Carolina. It is representative of a 300-year-old nuclear waste glass and was intended as a conservative compromise between 10-year-old waste and 1000-year-old waste. The feedstock material for this glass was supplied by Savannah River Laboratory, Aiken, SC, as SRL-165 black frit to which was added Ba, Cs, Mo,… more
Date: August 1, 1986
Creator: Wald, J. W. & Daniel, J. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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mu. /sup +/SR in amorphous spin glasses Pd/sub 75/Fe/sub 5/Si/sub 20/ and Pd/sub 75/Fe/sub 5/P/sub 5/

Description: The zero-field muon spin relaxation function G/sub zz/(t) has been measured as a function of reduced temperature t = T/T/sug g/ in the amorphous metallic spin glasses Pd/sub 75/Fe/sub 5/Si/sub 20/ and Pd/sub 75/Fe/sub 5/P/sub 20/. The results are in qualitative agreement with earlier measurements on dilute alloy spin glasses, including an onset of static order below T/sub g/ and a (t/(t - 1))/sup 2/ dependence of the correlation time tau/sub c/ above T/sub g/. Both samples have the same tau/sub… more
Date: January 1, 1986
Creator: Brewer, J. H.; Spencer, D. P.; Huang, C. Y.; Uemura, Y. J. & Chen, H. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infrared and Raman investigation of rare-earth phosphate glasses for potential use as radioactive waste forms

Description: This project was designed to investigate the properties of the rare-earth phosphate glasses CeO{sub 2}-P{sub 2}O{sub 5} and Pr{sub 2}O{sub 3}-P{sub 2}O{sub 5} for potential use as radioactive waste glasses. The research involved determination of the glass-forming region, loading capacity, and optimum processing parameters of the glasses. Structural studies of the unloaded host glasses and glasses loaded with simulated waste elements were to be done using Raman, infrared and infrared reflection … more
Date: November 10, 1986
Creator: Morgan, S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fabrication and characterization of MCC approved testing material: ATM-9 glass

Description: The Materials Characterization Center ATM-9 glass is designed to be representative of glass to be produced by the Defense Waste Processing Facility at the Savannah River Plant, Aiken, South Carolina. ATM-9 glass contains all of the major components of the DWPF glass and corresponds to a waste loading of 29 wt %. The feedstock material for this glass was supplied by Savannah River Laboratory, Aiken, SC, as SRL-165 Black Frit to which was added Ba, Cs, Md, Nd, Zr, as well as /sup 99/Tc, depleted … more
Date: June 1, 1986
Creator: Wald, J.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microstructural characterization of primary coolant pipe steel

Description: Atom probe field-ion microscopy, analytical electron microscopy, and optical microscopy have been used to investigate the changes that occur in the microstructure of cast CF 8 primary coolant pipe stainless steel after long term thermal aging. The cast duplex microstructure consisted of austenite with 15% delta-ferrite. Investigation of the aged material revealed that the ferrite spinodally decomposed into a fine scaled network of ..cap alpha.. and ..cap alpha..'. A fine G-phase precipitate was… more
Date: January 1, 1986
Creator: Miller, M. K. & Bentley, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structural evolution during recrystallization

Description: The evidence showing the failure of the classic Johnson-Mehl-Avrami equation to describe most recrystallization kinetics is reviewed. The failure is seen in the value of the exponent n which is much less than the theoretically predicted exponents. The reason for this failure is at least in part due to the nonrandom distribution of nucleation sites. This nonrandom distribution seems to arise from the grain to grain variation in deformation microstructure. Simple 3-dimensional and more precise 2-… more
Date: January 1, 1986
Creator: Doherty, R. D.; Rollett, A. R. & Srolovitz, D. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stability of multilayers for short-wavelength optics

Description: A variety of multilayer mirrors with transition metal absorber layers (W-C, Wre-C, Co-C, and Cr-C) have been fabricated and tested up to 1000 C using standard 0.20 x-ray diffraction, Debye-Scherrer scattering and microcleavage transmission electron microscopy. The 0-20 x-ray diffraction during annealing shows the Bragg peak position to shift toward lower angles with increasing temperature. This irreversible shift starts at around 300 C and is equivalent to as much as 12% expansion of the multil… more
Date: March 1, 1986
Creator: Ziegler, E.; Lepetre, Y.; Schuller, I.K.; Viccaro, P.J. & Spiller, E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Irradiation disordering and ordering of Cu/sub 3/Au by fusion neutrons

Description: Ordered and partially ordered Cu/sub 3/Au alloys (S = .30 - .99) have been irradiated at 4K and 300K with fusion neutrons at RTNS-II. The disordering rate was measured by monitoring electrical resistivity. The analysis of 4K irradiations and a comparison with fission reactor irradiations indicated that the disordering rate depended upon the long-range order parameter, S, dS/d phi t = -S(k/sub 1/-k/sub 2/S), where k/sub 1/ and k/sub 2/ are scaled with damage energy. The results of 300K irradiati… more
Date: March 18, 1986
Creator: Huang, J.S.; Guinan, M.W. & Hahn, P.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Complementary AES and AEM of grain boundary regions in irradiated. gamma. '-strengthened alloys

Description: Two microchemical analysis techniques are used to measure solute segregation at grain boundaries in two ..gamma..'-strengthened, fcc Fe-Ni-Cr alloys that display radiation-induced intergranular fracture. Scanning Auger electron spectroscopy (AES) of grain boundary fracture surfaces and analytical electron microscopy (AEM) of intact grain boundaries using energy-dispersive x-ray spectroscopy show good agreement on the nature and extent of segregation. The elements Ni, Si, Ti, and Mo are found to… more
Date: January 1, 1986
Creator: Farrell, K.; Kishimoto, N.; Clausing, R.E.; Heatherly, L. & Lehman, G.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Microanalysis by electron energy loss spectroscopy at 300kV

Description: Some features of the anticipated improvements in microanalysis by electron energy loss spectroscopy (EELS) at 300 kV compared to opeation at 100kV have been studied with the use of a Philips EM430T equipped with Gatan 607 EELS and EDAX 9100/70 systems. Detailed measurements have been made on a range of specimens, with emphasis on boron nitride and silicon carbide.
Date: January 1, 1986
Creator: Bentley, J. & Angelini, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Vibrational soliton: an experimental overview

Description: To date the most convincing evidence of vibrational solitons in biopolymers has been found in two very disparate systems: Davydov-like excitations in hydrogen-bonded linear chains (acetanilide and N-methylacetamide) which are not biopolymers but plausible structural paradigms for biopolymers, and longitudinal accoustic modes of possibly nonlinear character in biologically viable DNA. 17 refs., 4 figs.
Date: March 8, 1986
Creator: Bigio, I.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation-enhanced recrystallization in copper alloys

Description: Two high-strength copper alloys, cold-worked-and-aged AMZIRC (Cu-Zr) and AMAX-MZC (Cu-Cr-Zr-Mg), were irradiated with 14-MeV Cu ions to a damage level of 10 dpa at temperatures of 100 to 500/sup 0/C. Cross-section examination of the irradiated foils using electron microscopy revealed signs of irradiation-enhanced recrystallization for irradiation temperatures above 300/sup 0/C. The recrystallization temperature for both alloys is about 450/sup 0/C during thermal annealing for a time similar to … more
Date: January 1, 1986
Creator: Zinkle, S. J.; Kulcinski, G. L. & Mansur, L. K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of strain and strain rate on residual microstructures in copper

Description: Several specimens of OFE Cu were deformed in compression to study the resulting microstructures at equivalent levels of threshold stress and strain. Equiaxed, diffuse dislocation cells are more persistent in Cu when tested at strain rates exceeding 10/sup 3/ sec/sup -1/. At quasi-static strain rates, dislocation collapse into more distinct, narrow microbands occurs at lower strain levels.
Date: January 1, 1986
Creator: Stevens, M.F. & Follansbee, P.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Re-examination of the neptunium-hydrogen system

Description: New P-C-T studies have been made on the Np + H system, using ultrapure double-electrorefined metal. Measurements were carried out over six orders of magnitude in pressure, from 0.0005 to 70 bar. The solubility of hydrogen was found to be very low. Metal-dihydride plateaus were flat, the two-phase boundary extremely sharp; this occurred at the unusual value H/Np approx. = 2.13. The dihydride lattice expanded upon addition of hydrogen, also in contrast to other trivalent rare-earth and actinide h… more
Date: January 1, 1986
Creator: Ward, J.W.; Bartscher, W. & Rebizant, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Site occupations in Li/sub 2/ ordered alloys by axial electron channeling microanalysis. [Ni/sub 3/AlX (X = Co, Hf, Fe)]

Description: Experiments using analytical electron microscopes were performed on Ni/sub 3/Al alloys with additions of Fe, Co, or Hf. Corrections had to be made for delocalization effects. Results agree with atom probe field-ion microscopy. (DLC)
Date: January 1, 1986
Creator: Bentley, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Collapse of Defect Cascades to Dislocation Loops

Description: We review a number of experiments that we have recently performed to investigate the collapse of defect cascades to dislocation loops. This important ion and neutron irradiation phenomenon has been studied with in situ ion bombardment in the Argonne National Laboratory High Voltage Electron Microscope-Ion Accelerator Facility at temperatures of 30 and 300/sup 0/K in Cu/sub 3/Au, Cu, and Fe, and 30, 300 and 600/sup 0/K in Ni. These experiments have demonstrated that individual defect cascades co… more
Date: April 1, 1986
Creator: Kirk, M. A.; Robertson, I. M.; Jenkins, M. L.; English, C. A.; Black, T. J. & Vetrano, J. S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Atomistic simulations of (001) symmetric tilt boundaries in Ni/sub 3/Al

Description: We report a systematic atomistic simulation study of (001) symmetric tilt grain boundaries (GB) in Ni/sub 3/Al, Ni, and Al. We found that the grain boundary energies and cohesive energies of Ni/sub 3/Al and pure fcc Ni are approximately the same. Grain boundary energies and cohesive energies in Ni/sub 3/Al depends strongly on the grain boundary composition. The Al-rich boundaries have highest grain boundary energies and lowest cohesive energies. This offers an explanation for the stoichiometric… more
Date: January 1, 1986
Creator: Chen, S. P.; Voter, A. F. & Srolovitz, D. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Precipitation of krypton in an amorphous Ti-Cr alloy. [Ti-Cr Thin Films]

Description: Results of a TEM investigation of the microstructural changes produced by the room temperature implantation of energetic Kr/sup +/ ions into a glassy Ti-Cr thin film are reported. As in other metals, the Kr precipitates as solid crystallites. The precipitation of crystalline Kr is accompanied by ultrafine crystallization of the metal host around each Kr crystal. With increasing fluence, the Kr precipitates grow to a critical size at which they melt, and the adjacent fine metal crystals disappea… more
Date: December 1, 1986
Creator: Allen, C. W. & Birtcher, R. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Atomic-defect mechanisms for diffusion in refractory bcc metals

Description: Despite a number of recent investigations into the nature and properties of equilibrium atomic defects in the refractory bcc metals, the mechanisms responsible for the high-temperature mass transport in these materials are not clear. The observed strong high-temperature enhancement in self-diffusion appears to be unexplainable in terms of divacancies, but might result from the presence of small equilibrium concentrations of highly-mobile self-interstitials. Recent vacancy formation measurements… more
Date: September 1, 1986
Creator: Siegel, R. W.; Mundy, J. N. & Smedskjaer, L. C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phases in U-Si alloys

Description: The binary (two component) U-Si system contains a total of seven ''compounds.'' The most U-rich compounds are of interest to the RERTR community because they are now being employed as fuels in research and test reactors. The nomenclature used in describing these fuels and the metallurgical significance of the notations recorded may have different meanings to people from different technical backgrounds. This paper is a succinct exploration of the principles of phase equilibria and the realities … more
Date: September 1, 1986
Creator: Domagala, R.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The effect of cooling rate during rapid solidification on the structure and texture of NiTi

Description: A study has been conducted on the effects of increasing cooling rate during rapid solidification of NiTi upon the phases that are produced. The hammer and anvil rapid solidification technique and laser melting with a nanosecond excimer laser were used, which allow the cooling rate to be varied by three to four orders of magnitude. Although 1/3 (110) superlattice reflections are seen in the selected area diffraction (SAD) patterns of the splat quenched (SQ) specimens, x-ray diffraction analyses … more
Date: January 1, 1986
Creator: Pedraza, A. J.; Godbole, M. J.; Kenik, E. A.; Pedraza, D. F. & Lowndes, D. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Unusual angular and temperature dependence of the upper critical field in UPt/sub 3/

Description: We report measurements of the upper critical field, H/sub c2/, inclined at various angles with respect to the c-axis in the heavy fermion superconductor UPt/sub 3/. The angular anisotropy observed near T/sub c/ = 0.53K cannot be explained quantitatively by presently available theoretical expressions which consider either isotropic or anisotropic pairing. In addition, we find that the anisotropy apparently disappears at T /approximately/200 mK, only to reemerge at lower temperatures with an oppo… more
Date: June 1, 1986
Creator: Shivaram, B. S.; Rosenbaum, T. F. & Hinks, D. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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