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Fusion Techniques for the Oxidation of Refractory Actinide Oxides

Description: Small-scale experiments were performed to demonstrate the feasibility of fusing refractory actinide oxides with a series of materials commonly used to decompose minerals, glasses, and other refractories as a pretreatment to dissolution and subsequent recovery operations. In these experiments, 1-2 g of plutonium or neptunium oxide (PuO<sub>2</sub> or NpO<sub>2</sub>) were calcined at 900 degrees Celsius, mixed and heated with the fusing reagent(s), and dissolved. For refractory PuO<sub>2</sub>, … more
Date: April 15, 1999
Creator: Rudisill, T.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Use of high gradient magnetic separation for actinide application

Description: Decontamination of materials such as soils or waste water that contain radioactive isotopes, heavy metals, or hazardous components is a subject of great interest. Magnetic separation is a physical separation process that segregates materials on the basis of magnetic susceptibility. Because the process relies on physical properties, separations can be achieved while producing a minimum of secondary waste. Most traditional physical separation processes effectively treat particles larger than 70 m… more
Date: August 1, 1996
Creator: Avens, L. R.; Worl, L. A. & Padilla, D. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Decontamination of matrices containing actinide oxides

Description: There is provided a method for removing actinides and actinide oxides, particularly fired actinides, from soil and other contaminated matrices, comprising: (a) contacting a contaminated material with a solution of at least one inhibited fluoride and an acid to form a mixture; (b) heating the mixture of contaminated material and solution to a temperature in the range from about 30 C to about 90 C while stirring; (c) separating the solution from any undissolved matrix material in the mixture; (d)… more
Date: December 1, 1997
Creator: Villarreal, Robert
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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Early actinide organonitrile compounds and their reactivity.

Description: The actinide trihalides are an important class of materials . Anhydrous AnX3 compounds have been prepared via high temperature synthetic techniques, but they exis t as polymeric solids, which are insoluble in organic solvents . 1-3 Transuranic complexe s AnI3(THF)X have been prepared by the reaction of metals with CZH4IZ in THF solution s (An = Pu, x = 5; An = Np, x = 4) 4 and can be viewed as a net oxidation of An metal wit h 1 .5 equivalents molecular iodine. A convenient preparation of organ… more
Date: January 1, 2003
Creator: Enriquez, A. E. (Alejandro E.); Matonic, J. H. (John H.); Scott, B. L. (Brian L.) & Neu, M. P. (Mary P.)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A comparison of long-term retention of plutonium oxide in lung based on excretion data with observed lung burdens at autopsy

Description: Experience in the nuclear industry has shown that the most frequent route for significant plutonium deposition in man is by inhalation. After an accidental inhalation exposure to plutonium oxide has occurred, an attempt is usually made to determine the lung burden using in-vivo measurement techniques. However, this will not be possible if the amount deposited is less than the detection capability of the counter. Likewise, it may not be possible for even larger intakes if they are first discover… more
Date: May 1, 1985
Creator: Heid, K.R.; Jech, J.J.; Kathren, R.L. & Sula, M.J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of plutonium oxide leak rates from shipping containers. Quarterly progress report, October 1, 1977--December 31, 1977

Description: The study was initiated in Oct. 1976. Several tasks are to be undertaken. In combination, they have the end objective of defining the leak rates of plutonium oxide from characterized leaks in shipping containers. Research progress is reported on each of the four tasks. (TFD)
Date: January 1, 1978
Creator: Schwendiman, L. C.; Pobereskin, M.; Mishima, J.; Sutter, S. L.; Madia, W. J.; Schmidt, E. W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Study of plutonium oxide leak rates from shipping containers. Quarterly progress report, April 1, 1977--June 30, 1977

Description: The study was initiated in October, 1976. Several tasks are to be undertaken in the study. In combination, they have the end objective of defining the leak rates of plutonium oxide powder from characterized leaks. This is the third quarterly report of this work. Previous reports were issued as BNWL-2260-1 and -2. Progress on each of the tasks is reported. (TFD)
Date: July 1, 1977
Creator: Schwendiman, L. S.; Pobereskin, M.; Mishima, J.; Sutter, S. L.; Madia, W. J.; Schmidt, E. W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Assigning mass values to in-house standard UF/sub 6/ cylinders

Description: A statistical experimental design called the Fast 4-1 Series is used to assign mass values to in-house standard UF/sub 6/ cylinders. This design is intended to minimize the number of weighings of large cylinders yet provide acceptable estimates of mass values and their precision. 5 refs.
Date: January 1, 1987
Creator: Goldman, A.; McGuire, D. & Croarkin, C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Synthesis of crystalline americium hydroxide, Am(OH){sub 3}, and determination of its enthalpy of formation; estimation of the solubility-product constants of actinide(III) hydroxides

Description: This paper reports a new synthesis of pure, microcrystalline Am(OH){sub 3}, its characterization by x-ray powder diffraction and infrared spectroscopy, and the calorimetric determination of its enthalpy of solution in dilute hydrochloric acid. From the enthalpy of solution the enthalpy of formation of Am(OH){sub 3} has been calculated to be {minus}1371.2{plus_minus}7.9 kj{center_dot}mol{sup {minus}1}, which represents the first experimental determination of an enthalpy of formation of any actin… more
Date: December 31, 1993
Creator: Morss, L. R. & Williams, C. W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Magnetic properties of actinide systems

Description: Early expectations that the proximity of the 5f band to the Fermi level would lead to complex magnetic (or almost magnetic) behaviour were correct. Well documented examples of spin-fluctuation systems, itinerant and localized magnetic systems now exist. Rather than attempt a complete survey of the experimental results, this review focusses on three systems of major importance; (a) the elements, (b) Laves phase compounds, and (c) NaCl-type compounds. In (a) the main advances have come in theorie… more
Date: January 1, 1977
Creator: Lander, G. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermochemistry of the actinides

Description: The measurement of equilibria by Knudsen effusion techniques and the enthalpy of formation of the actinide atoms is briefly discussed. Thermochemical data on the sublimation of the actinide fluorides is used to calculate the enthalpies of formation and entropies of the gaseous species. Estimates are made for enthalpies and entropies of the tetrafluorides and trifluorides for those systems where data is not available. The pressure of important species in the tetrafluoride sublimation processes i… more
Date: October 1, 1993
Creator: Kleinschmidt, P. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Estimating particle release through gas leaks in dry powder shipping containers

Description: Information is presented from which an estimate can be made of the release of plutonium oxide from shipping containers. The leak diameter is estimated from gas leak tests of the container and an estimate is made of gas leak rate as a function of pressure over the time of interest in the accident. These calculations are limited in accuracy because of assumptions regarding leak geometry and the basic formulations of hydrodynamic flow for the assumed conditions. Sonic flow is assumed to be the lim… more
Date: June 1, 1977
Creator: Schwendiman, L.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Orbital effects in actinide systems

Description: Actinide magnetism presents a number of important challenges; in particular, the proximity of 5f band to the Fermi energy gives rise to strong interaction with both d and s like conduction electrons, and the extended nature of the 5f electrons means that they can interact with electron orbitals from neighboring atoms. Theory has recently addressed these problems. Often neglected, however, is the overwhelming evidence for large orbital contributions to the magnetic properties of actinides. Some … more
Date: January 1, 1983
Creator: Lander, G.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The relative radiation resistance of zirconolite, pyrochlore and perovskite to 1.5 MeV Kr{sup +} ions

Description: Zirconolite (CaZrTi2O7), pyrochlore (VIIIA2 VIB2 IV X6Y) and perovskite (CaTiO3) are candidate phases for the immobilisation of rare earth elements (REEs) and actinides (ACTs) in various high level radioactive waste (HLW) forms 1. The effect of radiation damage on the structure and consequently on the durability of these phases is important to predictive modelling of their behaviour in the repository environment and risk assessment.
Date: March 1, 1997
Creator: Smith, K. L.; Zaluzec, N. J. & Lumpkin, G. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Thermodynamics and sublimation chemistry of plutonium - oxygen - chlorine

Description: Pyrochemical processing of plutonium produces spent salts that contain plutonium bearing species. One of the species is PuOCl. The behavior of pure PuOCl at high temperatures and PuOCl in the liquid salt matrix is not well characterized. The purpose of the study is to establish the vapor pressure and vapor composition for the sublimation of PuOCl. The results of the sublimation study and the thermodynamic properties associated with the sublimation process are presented.
Date: July 1, 1993
Creator: Williamson, M. A. & Kleinschmidt, P. D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Study of plutonium oxide leak rates from shipping containers. Quarterly progress report, January 1, 1977--March 31, 1977

Description: The status of the following tasks is reported: review literature and theoretical work relating to transmission of particles through channels; investigate the relationship of gas flow rates, leak geometries, pressures, and temperatures; measure transmission of a well characterized simulant (UO/sub 2/ powder) through several leaks; measure fuel grade PuO/sub 2/ leaks through a ''standard leak'' incorporated into a suitable container; measure fuel grade PuO/sub 2/ leak rates from a simulated leaki… more
Date: April 1, 1977
Creator: Schwendiman, L. C.; Pobereskin, M.; Mishina, J.; Sutter, S. L.; Madia, W. J. & Schmidt, E. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Quarterly progress report, April 2-June 29, 1979 - Study of plutonium oxide leak rates from shipping containers.

Description: The study was initiated in October 1976. Several tasks are to be undertaken in this study which, when combined, have the end objective of defining the leak rates of plutonium dioxide powder from characterized leaks. Each task is identified and the progress during the reporting period is briefly described.
Date: July 1, 1979
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Structural and magnetic characterization of actinide materials

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The authors have successfully used neutron scattering techniques to investigate physicochemical properties of elements, compounds, and alloys of the light actinides. The focus of this work is to extend the fundamental research capability and to address questions of practical importance to stockpile integrity and long-term storage of nuclear material. Sp… more
Date: December 31, 1998
Creator: Cort, B.; Allen, T. H. & Lawson, A. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chemical flowsheet conditions for preparing urania spheres by internal gelation

Description: Small, ceramic urania spheres can be prepared for use as nuclear fuel by internal chemical gelation of uranyl nitrate solution droplets. Decomposition of hexamethylenetetramine (HMTA) dissolved in the uranyl nitrate solution releases ammonia to precipitate hydrated UO/sub 3/. Previously established flowsheet conditions have been improved and modified at ORNL and have been applied to prepare dense UO/sub 2/ spheres with average diameters of 1200, 300, and 30 ..mu..m.
Date: July 1, 1979
Creator: Haas, P.A.; Begovich, J.M.; Ryon, A.D. & Vavruska, J.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Portable load-cell based system for weighing UF/sub 6/ cylinders

Description: A load-cell-based portable weighing system which is capable of verifying the weights of 2.2 tonne 30-inch UF/sub 6/ cylinders has been developed by the US National Bureau of Standards (NBS). This system weighs about 13 kg and has an attainable accuracy of about 1 kg. After an initial calibration at NBS, the system is ready for use in the field. Approximately 5 to 10 minutes are needed for assembly, and, if an overhead crane has access to all cylinders to be weighed, from 10 to 15 weighings may … more
Date: January 1, 1982
Creator: Fainberg, A.; Gordon, D.; Dermendjiev, E.; Terrey, D. & Mitchell, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Enthalpy and heat capacity of solid UO/sub 2/

Description: Equations have been derived based upon a reevaluation of the enthalpy and heat-capacity data of UO/sub 2/. We recommend a three-term nonlinear equation below 2670 K, with terms representing contributions from phonons, volumetric thermal expansion, and electrons, and a linear equation above 2670 K.
Date: May 1, 1981
Creator: Fink, J.K.; Chasanov, M.G. & Leibowitz, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mechanistic interpretation of glass reaction: Input to kinetic model development

Description: Actinide-doped SRL 165 type glass was reacted in J-13 groundwater at 90{degrees}C for times up to 278 days. The reaction was characterized by both solution and solid analyses. The glass was seen to react nonstoichiometrically with preferred leaching of alkali metals and boron. High resolution electron microscopy revealed the formation of a complex layer structure which became separated from the underlying glass as the reaction progressed. The formation of the layer and its effect on continued g… more
Date: May 1, 1991
Creator: Bates, J. K.; Ebert, W. L.; Bradley, J. P. & Bourcier, W. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Actinide halide complexes

Description: A compound of the formula MX{sub n}L{sub m} wherein M = Th, Pu, Np,or Am thorium, X = a halide atom, n = 3 or 4, L is a coordinating ligand selected from the group consisting of aprotic Lewis bases having an oxygen-, nitrogen-, sulfur-, or phosphorus-donor, and m is 3 or 4 for monodentate ligands or is 2 for bidentate ligands, where n + m = 7 or 8 for monodentate ligands or 5 or 6 for bidentate ligands, a compound of the formula MX{sub n} wherein M, X, and n are as previously defined, and a pro… more
Date: February 7, 1991
Creator: Avens, Larry R.; Zwick, Bill D.; Sattelberger, Alfred P.; Clark, David L. & Watkin, J. G.
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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