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Auger study of surface carbon and oxygen on thorium following ion bombardment

Description: The composition of a thorium metal surface has been monitored using Auger electron spectroscopy following Ar/sup +/ bombardment at different temperatures. After extended Ar/sup +/ bombardment, enough contaminated overlayers were removed to expose a surface region containing only thorium, bulk impurities, and imbedded argon. The main impurities, carbon and oxygen, differed in their behavior when the sample was annealed following bombardment. The amount of surface carbon either increased or remai… more
Date: November 17, 1977
Creator: Bastasz, R. & Colmenares, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Summary of beryllium specifications

Description: This report summarizes and compares the main beryllium properties included in producer, Department of Energy (formerly ERDA) facility, and government specifications. These data are tabulated in a sequence established primarily by increasing purity and secondarily by increasing tensile properties. Comments on formability and weldability are also included.
Date: February 17, 1978
Creator: Corle, R. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Statistical characterization of dislocation ensembles

Description: We outline a method to study the spatial and orientation statistics of dynamical dislocation systems by modeling the dislocations as a stochastic fiber process. Statistical measures have been introduced for the density, velocity, and flux of dislocations, and the connection between these measures and the dislocation state and plastic distortion rate in the crystal is explained. A dislocation dynamics simulation model has been used to extract numerical data to study the evolution of these statis… more
Date: May 17, 2006
Creator: El-Azab, A.; Deng, J. & Tang, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Final Report

Description: The premise of this project was that coordination chemistry could be used to devise new kinds of microporous materials and that these materials could exhibit nanoscale porosity and selective chemical separation capabilities. Our initial materials focus was on aggregates of discrete hollow molecules, especially molecular squares. Subsequently our focus turned largely toward permanently microporous metal-organic frameworks (MOFs). Our approach emphasized coupling predictive & explanative computat… more
Date: November 17, 2008
Creator: Hupp, Joseph T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of the Quantrum Structure of Surfaces with Far UV Excitation Spectrosscopies

Description: Clean surfaces and those with adsorbates have been investigated to obtain electronic and atomic structure data. The various modes of synchrotron radiation (SR) photoemission spectroscopy (PES) have been performed mostly beam line 7.0.1 at the Advanced Light Source (ALS) in Berkeley, CA and some at the Synchrotron Radiation Center (SRC) in Madison, WI. These were done on silicon, carbon, and group III nitrides.
Date: October 17, 2008
Creator: Lapeyre, Gerlad
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Cooperative Research and Development of Primary Surface Recuperator for Advanced Microturbine Systems

Description: Recuperators have been identified as key components of advanced gas turbines systems that achieve a measure of improvement in operating efficiency and lead the field in achieving very low emissions. Every gas turbine manufacturer that is studying, developing, or commercializing advanced recuperated gas turbine cycles requests that recuperators operate at higher temperature without a reduction in design life and must cost less. The Solar Cooperative Research and Development of Primary Surface Re… more
Date: January 17, 2007
Creator: Escola, George
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of Irradiation Embrittlement of A508 Gr 4N and Comparison to Other Low-Alloy Steels

Description: A508 Gr 4N has improved fracture toughness because of the addition of 3% nickel, compared to typical low alloy steels which have less than 1% nickel. However, there is an expectation in much of the recent literature, based mostly on low-alloy steels with nickel below 1%, that irradiation embrittlement will increase with increasing nickel (Ni) content. In contrast, the raw irradiation test data show that ASTM A508 Grade 4N containing up to 3.7% nickel, 0.1% Cu and 0.01% P does not show enhanced … more
Date: June 17, 2002
Creator: G.L. Wire, W. J. Beggs and T.R. Leax
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Breakdown Limits on Gigavolt-per-Meter Electron-Beam-Driven Wakefields in Dielectric Structures

Description: First measurements of the breakdown threshold in a dielectric subjected to GV/m wakefields produced by short (30-330 fs), 28.5 GeV electron bunches have been made. Fused silica tubes of 100 {micro}m inner diameter were exposed to a range of bunch lengths, allowing surface dielectric fields up to 27 GV/m to be generated. The onset of breakdown, detected through light emission from the tube ends, is observed to occur when the peak electric field at the dielectric surface reaches 13.8 {+-} 0.7 GV/… more
Date: June 17, 2008
Creator: Thompson, M. C.; Badakov, H.; Cook, A. M.; Rosenzweig, J. B.; Tikhoplav, R.; Travish, G. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Cost-Effective Cementitious Material Compatible with Yucca Mountain Repository Geochemistry

Description: The current plans for the Yucca Mountain (YM) repository project (YMP) use steel structures to stabilize the disposal drifts and connecting tunnels that are collectively over 100 kilometers in length. The potential exist to reduce the underground construction cost by 100s of millions of dollars and improve the repository's performance. These economic and engineering goals can be achieved by using the appropriate cementitious materials to build out these tunnels. This report describes the requir… more
Date: December 17, 2004
Creator: Dole, LR
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High threshold HR (highly reflective) coatings at 1064 nm

Description: We have conducted as extensive series of laser damage measurements on highly reflective (HR) dielectric coatings which have yielded 1064-nm thresholds as high as 40 J/cm{sup 2} for 8- to 10-ns pulses at pulse-repetition frequencies (PRF) of 10 Hz. Moreover, by laser conditioning these coatings with subthreshold pulses, the thresholds of some coatings were raised to levels exceeding 70 J/cm{sup 2}. These are the highest threshold dielectric HR coatings that we have tested in this regime. The coa… more
Date: December 17, 1990
Creator: Rainer, F.; DeMarco, F. P.; Hunt, J. T.; Morgan, A. J.; Mott, L. P.; Marcelja, F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Heavy wall pressure vessels for energy systems

Description: Modifications of steels currently accepted in the Code appear to provide improved mechanical properties. These steels may permit the fabrication of larger diameter vessels with thinner section sizes and improved reliability and integrity. Adapting current specifications should expedite Code approval. Finally the challenge of improving welding procedures and adapting processes for field applications will result in higher quality weldments.
Date: June 17, 1980
Creator: Canonico, D.A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Analysis of measurements of the thermal conductivity of liquid urania

Description: An analysis was performed of the three existing measurements of the thermal conductivity and thermal diffusivity of molten uranium dioxide. A transient heat transfer code (THTB) was used for this analysis. A much smaller range of values for thermal conductivity than originally reported was found: the original values ranged from 2.4 to 11 W . m/sup -1/ . K/sup -1/, with a mean of 7.3 W . m/sup -1/ . K/sup -1/, whereas the recalculated values ranged from 4.5 to 6.75 W . m/sup -1/ . K/sup -1/, wit… more
Date: September 17, 1984
Creator: Fink, J.K. & Leibowitz, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Optical properties and electronic structures of d- and f-electron metals and alloys, Ag-In, Ni-Cu, AuGa sub 2 , PtGa sub 2 ,. beta. prime -NiAl,. beta. prime -CoAl, CeSn sub 3 , and LaSn sub 3

Description: Optical properties and electronic structures of disordered Ag{sub 1- x}In{sub x}(x = 0.0, 0.04, 0.08, 0.12) and Ni{sub 1-x}Cu{sub x} (x = 0.0, 0.1, 0.3, 0.4) alloys and ordered AuGa{sub 2}, PtGa{sub 2}, {beta}{prime}-NiAl, {beta}{prime}-CoAl, CeSn{sub 3}, and LaSn{sub 3} have been studied. The complex dielectric functions have been determined for Ag{sub 1-x}In{sub x}, Ni{sub 1-x}Cu{sub x}, AuGa{sub 2}, and PtGa{sub 2} in the 1.2--5.5 eV region and for CeSn{sub 3} and LaSn{sub 3} in the 1.5--4.5… more
Date: October 17, 1990
Creator: Kim, Kwang Joo
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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High resolution microstructural and microchemical analysis of zirconia eutectic interfaces

Description: Resolution of microscopic analytical methods has greatly improved over the past decade, and it is now possible to examine periodic variations in structure and chemistry at a scale much finer than the spacing typical of eutectic structures (1-5 [mu]m). During the current year, studies were completed on ZrO[sub 2]-NiO and ZrO[sub 2]-MnO eutectic systems, and study was initiated on microchemical variation in two spinodal systems: Cu-Ni-Sn and SnO[sub 2]-TiO[sub 2]. Work was also initiated on metal… more
Date: March 17, 1993
Creator: Notis, Michael R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Laser conditioning and electronic defect measurements of HfO sub 2 and SiO sub 2 thin films

Description: Multilayer HfO{sub 2}/SiO{sub 2} high reflectors (HR) and polarizers show a permanent increase in their 1064-nm damage thresholds following laser conditioning at subthreshold fluences. Threshold increases of 2--3x are typical. In an effort to better understand the conditioning effect we have made laser conditioning and electronic property measurements on single layers of these two materials. The laser damage threshold of 1-{mu}m thick e-beam deposited SiO{sub 2} was increased by laser condition… more
Date: December 17, 1990
Creator: Kozlowski, M.R.; Staggs, M.; Rainer, F. (Lawrence Livermore National Lab., CA (USA)) & Stathis, J.H. (International Business Machines Corp., Yorktown Heights, NY (USA). Thomas J. Watson Research Center)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Method for determining the work hardening function to describe plasticity of metals

Description: A method for obtaining a constitutive relation that relates the flow stress to the equivalent plastic strain is developed. The method uses simple tension test data to suggest a functional form. This form is then used as a constitutive model in a computer program that simulates the tension test. The calculated results are compared with the experimental results and the functional form is refined until agreement is obtained between calculations and experiments. The importance of knowing the relati… more
Date: April 17, 1978
Creator: Wilkins, Mark L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Suppression of the uranium-hydrogen reaction using high-dose carbon implantation

Description: We have previously reported the delay and reduction of the hydriding of uranium by implantation of oxygen. The reduced hydriding was attributed to the presence of the uranium oxide layer created near room temperature. In this paper we present results for the layers formed by implantation of 80 keV C/sup +/ to a dose of 8E17 C/cm/sup 2/. The carbide layers formed were characterized by Auger electron spectroscopy, Rutherford backscattering, and glancing angle x-ray diffraction. Hydriding properti… more
Date: April 17, 1987
Creator: Musket, R.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Pile Temperature Study

Description: Regarding heat transfer studies of annular spaces around the process tube, there is general agreement among all concerned, that high graphite temperatures are essential at the initial startup. Pile Technology, in studying graphite damage, has developed information that shows little or no expansion occurring when temperatures are maintained at 275{degrees}C. Stored energy levels are less than 5% and K/Ko has saturated in the region of 3.5 to 4. Badly expanded samples (1% increase in length) have… more
Date: January 17, 1950
Creator: Jaske, R. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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HAPO irradiation of capsules containing UO{sub 2} specimens

Description: A knowledge of the effect of reactor irradiation on the properties of UO{sub 2} is relevant to the design and evaluation of UO{sub 2} fuel elements for the PRTR. Of particular interest is the effect of reactor irradiation on the thermal conductivity of sintered UO{sub 2} and the type, mechanism, and extent of radiation damage in sintered UO{sub 2}. In the latter case the study of fractured surfaces of irradiated UO{sub 2} specimens is a method of determining the extent of radiation damage. It i… more
Date: February 17, 1958
Creator: Newkirk, H. W.; Millhollen, M. K. & Brite, D. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Final reports on PT 105-551-A and Supplement A, ``High exposure thorium`` and PT 105-516-A, ``Effects of irradiation of thorium slugs``

Description: This report discusses Production Test 105-516-A which was written to determine the stability by both measurement and visual examination, of thorium slugs as used in flattening columns to exposures in excess of 400 MWD/AT. Both rolled and extruded thorium slugs were used; the highest exposures reached were about 1000 MWD/AT. Also discussed is Production Test 105-551-A which was written to demonstrate the stability of thorium slugs as used in flattening columns at exposures up to approximately 15… more
Date: November 17, 1954
Creator: Brugge, R. O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiation Laboratory, University of Notre Dame: Quarterly report, October 1--December 31, 1993

Description: The Notre Dame Radiation Laboratory is a facility of the Department of Energy operated for the DOE by the University of Notre Dame under contract No. DE-AC02-76ER00038. This quarterly report summarizes the progress on the programs within the Laboratory for the period of October 1, 193 through December 31, 1993. The activities of the staff during this period are noted. A list of publications is presented. A listing and a brief description of each of the reports issued during this quarter are pro… more
Date: February 17, 1994
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Drilling with fiber-transmitted, visible lasers

Description: High power and radiance copper-vapor laser technology developed at Lawrence Livermore National Laboratory shows great promise for many materials processing tasks. The authors recently transmitted the visible light produced by these lasers through fiber optics to perform hole drilling experiments. They found the tolerances on the hole circulatory and cylindricity to be excellent when compared to that produced by conventional optics. This technique lends itself to many applications that are diffi… more
Date: February 17, 1994
Creator: Kautz, D. D.; Berzins, L. V.; Dragon, E. P.; Werve, M. E. & Warner, B. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High resolution microstructural and microchemical analysis of zirconia eutectic interfaces. Progress report, July 1, 1992--June 30, 1993

Description: Resolution of microscopic analytical methods has greatly improved over the past decade, and it is now possible to examine periodic variations in structure and chemistry at a scale much finer than the spacing typical of eutectic structures (1-5 {mu}m). During the current year, studies were completed on ZrO{sub 2}-NiO and ZrO{sub 2}-MnO eutectic systems, and study was initiated on microchemical variation in two spinodal systems: Cu-Ni-Sn and SnO{sub 2}-TiO{sub 2}. Work was also initiated on metal… more
Date: March 17, 1993
Creator: Notis, M. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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