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PROCESSES FOR RECOVERY OF URANIUM AND THORIUM FROM GRAPHITE-BASE FUEL ELEMENTS. PART II

Description: Laboratory-scale tests on methods for recovering uranium and thorium from graphite-base reactor fuel elements are reported. The 90% HNO/sub 3/ process, which involves simultaneous disintegration and leaching in 21 M HNO/sub 3/, is applicable to all fuel elenments which do not contain coated fuel particles. Leaching of irradiated (0.001% burnup) fuels containing 3 and 12% uranlum recovered approximates 99.3 and 99.9%, respectively, of the uranium in two 4-hr leaches with boiling acid. The graphi… more
Date: November 30, 1961
Creator: Ferris, L.M.; Kibbey, A.H. & Bradley, M.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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General Chemistry Division quarterly report, July--September 1977

Description: Analytical research and development work is reported on multielement analysis, time-resolved spectroscopy, fluorescence analysis, ionization potential of NP, excited state chemistry, polarized x ray sources, potentiometric titration of Na, determination of TATB in DMSO, determination of nitrobenzene in TATB, analysis of explosive composites, mass spectrometer automation, mass spectra calculation, solids formation in geothermal brine, water quality laboratory automation, aerosol coagulation, and… more
Date: November 30, 1977
Creator: Harrar, J.E. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spectra of matrix isolated metal atoms and clusters. [In rare gases]

Description: The matrix isolation spectra of all of the 40 presently known atomic metal species show strong matrix effects. The transition energies are increased, and the bands are broad and exhibit splitting of sublevels which are degenerate in the gas phase. Several models have been proposed for splitting of levels, but basic effects are not yet understood, and spectra cannot be predicted, yet it is possible to correlate gas phase and matrix in many of the systems. Selective production of diatomics and cl… more
Date: September 30, 1977
Creator: Meyer, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Effect of water chemistry on the erosion-corrosion of aluminum in high temperature high velocity water

Description: This paper reports on a laboratory study of erosion-corrosion on aluminum surfaces in high temperature water. It is essentially a continuation of a similar previous study with refinement in testing procedure and the addition of electrochemical measurements to study the phenomenon. The electrochemical procedures are of intrinsic worth, because such measurements have never before been conducted with such an unusual cell geometry as imposed by the erosion-corrosion testing apparatus.
Date: January 30, 1970
Creator: Jones, D. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Controlled Synthesis of Polyenes by Catalytic Methods. Progress Report for the period December 1, 1989 - November 30, 1992

Description: A more direct approach to polyenes by the direct polymerization of acetylenes has been achieved. We were able to show that polymerization of acetylene itself can be controlled with a well- characterized alkylidene catalyst, but only if a base such as quinuclidine is present in order to slow down the rate of propagation relative to initiation. (Quinuclidine may also stabilize vinylalkylidene intermediates formed in the reaction). Unfortunately, living polyenes'' were no more stable than isolated… more
Date: November 30, 1992
Creator: Schrock, R. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stream sediment detailed geochemical survey for Date Creek Basin, Arizona

Description: Results of the Date Creek Basin detailed geochemical survey are reported. Field and laboratory data are reported for 239 stream sediment samples. Statistical and areal distributions of uranium and possible uranium-related variables are displayed. A generalized geologic map of the area is provided, and pertinent geologic factors which may be of significance in evaluating the potential for uranium mineralization are briefly discussed. Based on stream sediment geochemical data, significant concent… more
Date: June 30, 1980
Creator: Butz, T. R.; Tieman, D. J.; Grimes, J. G.; Bard, C. S.; Helgerson, R. N. & Pritz, P. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Synthesis of block copolymers of methyl siloxane, phenyl siloxane, vinyl siloxane, etc

Description: Synthesis of homo poly(dimethylsiloxane) PDMS, homo poly(diphenylsiloxane PDPS, and di- and tri- block copolymers of PDMS and PDPS have been carried out by anionic living polymerization, using the following reagents: hexamethylcyclotrisiloxane, HMTS and hexaphenylcyclotrisiloxane, HPTS (monomers), n-BuLi and dilithium diphenyldisilanolate, DLS (initiators), DMSO and THF (promoters) and Toluene (solvent). Lithium based catalysts are used in order to minimize siloxane rearrangement (equilibration… more
Date: June 30, 1979
Creator: Ibemesi, J.A. & Meier, D.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Ion-exchange of mordenite-type zeolite with Mg/sup 2 +/ and La/sup 3 +/

Description: Special techniques were tried for ion-exchanging Mg/sup 2 +/ and La/sup 3 +/ into mordenite, which is an acid-stable zeolite of possible catalytic value to the coal industry. Electron microprobe analysis showed that ion-exchange occurred only along the main channels of the 100 ..mu..m long needles. Complete exchange was not achieved, and exchange was always higher at the ends of the needles. The highest content of Mg/sup 2 +/ is 3.7 atoms per unit cell (with 0.2 Na and 1.0 K residual), and the … more
Date: September 30, 1977
Creator: Smith, J.V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Hydrides and Metal-Hydrogen Systems. Final Report

Description: The work reported deals with the preparation and physical properties, especially thermal dissociation pressures, and densities of hydrides, hydrogen- metal systems, and mixtures of hydrides with other substances. Possible applicatlons as moderators, high-temperature neutron shields, and low-temperature shields are cited and design problems discussed. Most of the data on dissociation pressures cover ranges and compounds not hltherto explored because of experimental difficulties and the basic kno… more
Date: April 30, 1951
Creator: Gibb, T. R. P., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of the solid, airborne materials created by the interaction of UF/sub 6/ with atmospheric moisture in a contained volume

Description: Several experiments have been performed in which UF/sub 6/ has been released into air under static conditions and contained in small release chambers (the largest was 8 cu ft) in order to characterize the solid product(s) created by reaction of the UF/sub 6/ with moisture in the air. Relative humidity of the air was varied, experiment to experiment, from < 2 to 100% and the amount of UF/sub 6/ released, experiment to experiment, varied from 5 to 230 mg. The releases were effected by rupture fro… more
Date: April 30, 1982
Creator: Pickrell, P. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photoinitiated electron transfer in multichromophoric species: Synthetic tetrads and pentads featuring diquinone moieties

Description: This project involves the design, synthesis and photophysical study of complex molecular systems engineered to achieve long lived charge separated states by a biomimetic, photoinitiated multistep electron transfer process. The use of these artificial systems to investigate different electron and energy transfer strategies will allow the evolution of more efficient molecular devices for the gathering of light energy and its transformation into chemical potential energy. The three major aspects o… more
Date: April 30, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photochemistry and enzymology of photosynthesis

Description: In the first task, a specially designed mass spectrometer system monitors the gas exchange occurring in response to single short flashes of light. This apparatus will be primarily used to study photosystem II donor reactions, such as the photooxidation of hydroxylamine, hydrazine, and hydrogen peroxide. This technique will also be used to study the light-induced exchange of O/sub 2/ and CO/sub 2/ in algae. The second task, biochemical studies, will focus on the role of chloroplast copper in pho… more
Date: July 30, 1979
Creator: Radmer, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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SPENT NUCLEAR FUEL STORAGE BASIN WATER CHEMISTRY: ELECTROCHEMICAL EVALUATION OF ALUMINUM CORROSION

Description: The factors affecting the optimal water chemistry of the Savannah River Site spent fuel storage basin must be determines in order to optimize facility efficiency, minimize fuel corrosion, and reduce overall environmental impact from long term spent nuclear fuel storage at the Savannah River Site. The Savannah River National Laboratory is using statistically designed experiments to study the effects of NO{sub 3}{sup -}, SO{sub 4}{sup 2-}, and Cl{sup -} concentrations on alloys commonly used not … more
Date: October 30, 2007
Creator: Hathcock, D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Transmission electron microscopy of actinide materials

Description: Actinide metallurgy, crystallography, physics, and chemistry are of great interest due to the unique behavior of the 5f states that dominate the electronic structure. The 5f states produce a wide range of fascinating behaviors in the actinide materials. from superconductivity to exotic magnetism. Accordingly, they are of great interest, but are difficult to work with. Transmission electron microscopy (TEM) can overcome many of the problems of working with actinide materials and can be used to i… more
Date: May 30, 2006
Creator: Moore, K
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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REVERSIBLE CONVERSION BETWEEN CHEMICAL AND ELECTRICAL ENERGIES CATALYZED BY Ru COMPLEXES AIMED TO CONSTRUCT SUSTAINABLE SOCIETY.

Description: The present study demonstrates that [Ru{sup II}(NH{sub 3})(q)(trpy)]{sup +} has an ability to oxidize alcohols catalytically under very mild conditions under electrolysis at +0.35 V in MeOH. The elucidation of the reaction mechanisms in the alcohol-oxidation is underway.
Date: November 30, 2007
Creator: TANAKA,K.; WADA, T.; FUJITA, E. & MUCKERMAN, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Progress Report No. 62 June 1-15, 1948

Description: This paper reports on the following programs: (1) 184-inch Cyclotron Program; (2) 60-inch Cyclotron Program; (3) Synchrotron Program; (4) Linear Accelerator Program; (5) Experimental Physics; (6) Theoretical Physics; (7) Isotope Separation Program; (8) Chemistry; and (9) Medical Physics.
Date: June 30, 1948
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spectroscopic Studies of Structure, Dynamics and Reactivity in Ionic Liquids.

Description: Ionic liquids (ILs) are a rapidly expanding family of condensed-phase media with important applications in energy production, nuclear fuel and waste processing, improving the efficiency and safety of industrial chemical processes, and pollution prevention. ILs are generally nonvolatile, noncombustible, highly conductive, recyclable and capable of dissolving a wide variety of materials. They are finding new uses in chemical synthesis, catalysis, separations chemistry, electrochemistry and other … more
Date: November 30, 2007
Creator: Wishart, J. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemical Imaging of Lipid Domains by High-Resolution Secondary Ion Mass Spectrometry

Description: Lipid microdomains within supported lipid bilayers composed of binary phosphocholine mixtures were chemically imaged by high-resolution secondary ion mass spectrometry performed with the NanoSIMS 50 (Cameca Instruments). This instrument images the sample components based on the elemental or isotopic composition of their atomic and small molecular secondary ions. Up to five different secondary ions can be simultaneously detected, and a lateral resolution of 50 nm can be achieved with high sensit… more
Date: September 30, 2005
Creator: Kraft, M L; Weber, P K; Longo, M L; Hutcheon, I D & Boxer, S G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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ELECTROCHEMICAL CORROSION STUDIES CORE 308 SEGMENTS 14R1 & 14R2 TANK 241-AY-102

Description: This document reports the results of electrochemical corrosion tests on AS1S Grade 60 carbon steel coupons exposed to tank 241-AY-102 sludge under conditions similar to those near the bottom of the tank. The tests were performed to evaluate the corrosive behavior of the waste in contact with sludge that does not meet the chemistry control limits of Administrative Control (AC) 5.15, Corrosion Mitigation Program.
Date: October 30, 2003
Creator: JB, DUNCAN & GA, COOKE
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tetraalkylphosphonium Polyoxometalates as Novel Ionic Liquids.

Description: The pairing of a Lindqvist or Keggin polyoxometalate (POM) anion with an appropriate tetraalkylphosphonium cation, [R{sub 3}R{prime}P]{sup +}, has been shown to yield an original family of ionic liquids (POM-ILs), among them salts liquid at or near ambient temperature. The physicochemical properties of several such 'inorganic liquids', in particular their thermal properties, suggests the possible application of these compounds as robust, thermally-stable solvents for liquid-liquid extraction. A… more
Date: November 30, 2007
Creator: Dietz, M. L.; Rickert, P. G.; Antonio, M. R.; Firestone, M. A.; Wishart, J. F. & Szreder, T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Standard Chemical-Thermodynamic Properties of Phosphorus and Some of its Key Compounds and Aqueous Species: An Evaluation of Differences between the Previous Recommendations of NBS/NIST and CODATA

Description: The aqueous chemistry of phosphorus is dominated by P(V), which under typical environmental conditions (and depending on pH and concentration) can be present as the orthophosphate ions H{sub 3}PO{sub 4}{sup 0}(aq), H{sub 2}PO{sub 4}{sup -}(aq), HPO{sub 4}{sup 2-}(aq), or PO{sub 4}{sup 3-}(aq). Many divalent, trivalent, and tetravalent metal ions form sparingly soluble orthophosphate phases that, depending on the solution pH and concentrations of phosphate and metal ions, can be solubility limit… more
Date: January 30, 2007
Creator: Rard, J A & Wolery, T J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Soft-x-ray spectroscopy study of nanoscale materials

Description: The ability to control the particle size and morphology of nanoparticles is of crucial importance nowadays both from a fundamental and industrial point of view considering the tremendous amount of high-tech applications. Controlling the crystallographic structure and the arrangement of atoms along the surface of nanostructured material will determine most of its physical properties. In general, electronic structure ultimately determines the properties of matter. Soft X-ray spectroscopy has some… more
Date: July 30, 2005
Creator: Guo, J.-H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Structure Based Predictive Model for Coal Char Combustion

Description: This unique collaborative project has taken a very fundamental look at the origin of structure, and combustion reactivity of coal chars. It was a combined experimental and theoretical effort involving three universities and collaborators from universities outside the U.S. and from U.S. National Laboratories and contract research companies. The project goal was to improve our understanding of char structure and behavior by examining the fundamental chemistry of its polyaromatic building blocks. … more
Date: December 30, 2000
Creator: Hurt, Robert; Calo, Joseph; Essenhigh, Robert & Hadad, Christopher
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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