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Chemical speciation of strontium, americium, and curium in high level waste: Predictive modeling of phase partitioning during tank processing. 1998 annual progress report

Description: 'In this research program, Pacific Northwest National Laboratory (PNNL) and Florida State University (FSU) are investigating the speciation of Sr and Am/Cm in the presence of selected organic chelating agents (ethylenediaminetetraacetic acid (EDTA), N-(2-hydroxyethyl)ethylenediaminetriacetic acid (HEDTA), nitrilotriacetic acid (NTA), and iminodiacetic acid (IDA)) over ranges of hydroxide, carbonate, ionic strength, and competing metal ion concentrations present in high level waste tanks. The fu… more
Date: June 1, 1998
Creator: Felmy, A. R.
Partner: UNT Libraries Government Documents Department
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Chemical and Ceramic Methods Toward Safe Storage of Actinides

Description: A very import, extremely-long-term, use for monazite as a radwaste encapsulant has been proposed. THe use of ceramic La-monazite for sequestering actinides (isolating them from the environment), especially plutonium and some other radioactive elements )e.g., fission-product rare earths), had been especially championed by Lynn Boatner of ORNL. Monazite may be used alone or, copying its compatibility with many other minerals in nature, may be used in diverse composite combinations.
Date: August 19, 2005
Creator: Morgan, P. E. D.; Housley, R. M.; Davis, J. B. & DeHaan, M. L.
Partner: UNT Libraries Government Documents Department
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THE DISCOVERY OF THE TRANSURANIUM ELEMENTS: THEIR HISTORY AND A PRESENTATION OF THE DIFFERENT METHODS USED IN THEIR DISCOVERY

Description: BS>The ten transuranium elements discovered since 1940 are discussed in chronological order. The discoverer, the history, and methods used are given for each element. Future developments in the discovery and preparation of transuranic elements are discussed. (A.C.)
Date: April 1, 1959
Creator: Thompson, S.G.
Partner: UNT Libraries Government Documents Department
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Interaction of Actinide Species with Microorganisms & Microbial Chelators: Cellular Uptake, Toxicity, & Implications for Bioremediation of Soil & Ground Water.

Description: Microorganisms influence the natural cycle of major elements, including C, N, P, S, and transition metals such as Mn and Fe. Bacterial processes can also influence the behavior of actinides in soil and ground water. While radionuclides have no known biological utility, they have the potential to interact with microorganisms and to interfere with processes involving other elements such as Fe and Mn. These interactions can transform radionuclides and affect their fate and transport. Organic acids… more
Date: March 28, 2006
Creator: Hakim Boukhalfa Mary, P. Neu Alvin Crumbliss
Partner: UNT Libraries Government Documents Department
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Separation of Minor Actinides from Lanthanides by Dithiophosphinic Acid Extractants

Description: The selective extraction of the minor actinides (Am(III) and Cm(III)) from the lanthanides is an important part of advanced reprocessing of spent nuclear fuel. This separation would allow the Am/Cm to be fabricated into targets and recycled to a reactor and the lanthanides to be dispositioned. This separation is difficult to accomplish due to the similarities in the chemical properties of the trivalent actinides and lanthanides. Research efforts at the Idaho National Laboratory have identified … more
Date: September 1, 2008
Creator: Peterman, D. R.; Greenhalgh, M. R.; Tillotson, R. D.; Klaehn, J. R.; Harrup, M. K.; Luther, T. A. et al.
Partner: UNT Libraries Government Documents Department
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The Estimation of Heats of Formation

Description: The procedure for estimation of heats of formation of compounds is illustrated by discussion of compounds of several of the elements of the actinide series. The procedure is particularly suited for lanthanide and actinide elements because of the similarity of the ionic radii and types of bonding.
Date: February 2, 1948
Creator: Brewer, Leo
Partner: UNT Libraries Government Documents Department
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Summary Report on New Transmutation Analysis for the Evaluation of Homogeneous and Heterogeneous Options in Fast Reactors

Description: A 1000 MWth commercial-scale Sodium Fast Reactor (SFR) design was selected as the baseline in this scenario study. Traditional approaches to Light Water Reactor (LWR) Spent Nuclear Fuel (SNF) transuranic waste (TRU) burning in a fast spectrum system have typically focused on the continual homogeneous recycling (reprocessing) of the discharge fast reactor fuel. The effective reduction of transuranic inventories has been quantified through the use of the transuranics conversion ratio (TRU CR). Th… more
Date: August 1, 2008
Creator: Ferrer, R. M.; Bays, S.; Pope, M.; Forget, B.; Skerjanc, W. & Asgari, M.
Partner: UNT Libraries Government Documents Department
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Feasibility of Recycling Plutonium and Minor Actinides in Light Water Reactors Using Hydride Fuel

Description: The objective of this DOE NERI program sponsored project was to assess the feasibility of improving the plutonium (Pu) and minor actinide (MA) recycling capabilities of pressurized water reactors (PWRs) by using hydride instead of oxide fuels. There are four general parts to this assessment: 1) Identifying promising hydride fuel assembly designs for recycling Pu and MAs in PWRs 2) Performing a comprehensive systems analysis that compares the fuel cycle characteristics of Pu and MA recycling in … more
Date: March 10, 2009
Creator: Greenspan, Ehud; Todreas, Neil & Taiwo, Temitope
Partner: UNT Libraries Government Documents Department
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Enhancing VVER Annular Proliferation Resistance Fuel with Minor Actinides

Description: Key aspects of the Global Nuclear Energy Partnership (GNEP) are to significantly advance the science and technology of nuclear energy systems and the Advanced Fuel Cycle (AFC) program. The merits of nuclear energy are the high-density energy, and low environmental impacts i.e. almost zero greenhouse gas emission. Planned efforts involve near-term and intermediate-term improvements in fuel utilization and recycling in current LWR as well as the longer-term development of new nuclear energy syste… more
Date: June 1, 2007
Creator: Chang, G. S.
Partner: UNT Libraries Government Documents Department
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Iron (II) and Silicate Effects on Mineralization and Immobilzation of Actinides

Description: Abstract - The unique composition of the Yucca Mountain repository site, which contains large concentrations of silicate in an oxidative environment, has required extensive research into compound formation involving uranium and iron(II) under such conditions. The possibility of uranium leakage from within the containment vessels into the near-field ground water, as well as iron leaching from the vessel itself, necessitates study of the individual contributions of these elements for compound for… more
Date: January 1, 2006
Creator: Sullens, Tyler A.; Gong, Cynthia-May S. & Szerwinski, Kenneth R.
Partner: UNT Libraries Government Documents Department
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Iron (III) Matrix Effects on Mineralization and Immobilization of Actinides

Description: Abstract - A number of models for the Yucca Mountain Project nuclear waste repository use studies of actinide sorption onto well-defined iron hydroxide materials. In the case of a waste containment leak, however, a complex interaction between dissolved waste forms and failed containment vessel components can lead to immediate precipitation of migratory iron and uranyl in the silicate rich near-field environment. Use of the Fe(III) and UO22+ complexing agent acetohydroxamic acid (AHA) as a color… more
Date: January 1, 2006
Creator: Gong, Cynthia-May S.; Sullens, Tyler A. & Czerwinski, Kenneth R.
Partner: UNT Libraries Government Documents Department
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A theoretical study of the ground state and lowest excited states of PuO0/+/+2 and PuO20/+/+2

Description: The ground and excited states of neutral and cationic PuO and PuO2 have been studied with multiconfigurational quantum chemical methods followed by second order perturbation theory, the CASSCF/CASPT2 method. Scalar relativistic effects and spin-orbit coupling have been included in the treatment. As literature values for the ionization energy of PuO2 are in the wide range of ~;;6.6 eV to ~;;10.1 eV, a central goal of the computations was to resolve these discrepancies; the theoretical results in… more
Date: December 8, 2008
Creator: Gibson, John K.; La Macchia, Giovanni; Infante, Ivan; Gagliardi, Laura & Raab, Juraj
Partner: UNT Libraries Government Documents Department
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Complexation of Gluconate with Uranium(VI) in Acidic Solutions: Thermodynamic Study with Structural Analysis

Description: Within the pC{sub H} range of 2.5 to 4.2, gluconate forms three uranyl complexes UO{sub 2}(GH{sub 4}){sup +}, UO{sub 2}(GH{sub 3})(aq), and UO{sub 2}(GH{sub 3})(GH{sub 4}){sup -}, through the following reactions: (1) UO{sub 2}{sup 2+} + GH{sub 4}{sup -} = UO{sub 2}(GH{sub 4}){sup +}, (2) UO{sub 2}{sup 2+} + GH{sub 4}{sup -} = UO{sub 2}(GH{sub 3})(aq) + H{sup +}, and (3) UO{sub 2}{sup 2+} + 2GH{sub 4}{sup -} = UO{sub 2}(GH{sub 3})(GH{sub 4}){sup -} + H{sup +}. Complexes were inferred from potent… more
Date: January 5, 2009
Creator: Zhang, Zhicheng; Helms, G.; Clark, S. B.; Tian, Guoxin; Zanonato, PierLuigi & Rao, Linfeng
Partner: UNT Libraries Government Documents Department
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Structural Characteristics, Population Analysis, and Binding Energies of [An(NO₃)]²⁺ (with An = Ac to Lr)

Description: Article reports on a systematic analysis of differences observed in the prediction of structural characteristics, electron withdrawing effects, and binding energies of [An(NO3)]2+ (with An = Ac to Lr) in gas and aqueous phases.
Date: October 25, 2018
Creator: Penchoff, Deborah A.; Peterson, Charles C.; Quint, Mark S.; Auxier, John D., II; Schweitzer, George K.; Jenkins, David M. et al.
Partner: University of North Texas
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Actinide Targets for Neutron Cross Section Measurements

Description: The Advanced Fuel Cycle Initiative (AFCI) and the Generation IV Reactor Initiative have demonstrated a lack of detailed neutron cross-sections for certain "minor" actinides, those other than the most common (235U, 238U, and 239Pu). For some closed-fuel-cycle reactor designs more than 50% of reactivity will, at some point, be derived from "minor" actinides that currently have poorly known or in some cases not measured (n,?) and (n,f) cross sections. A program of measurements under AFCI has begun… more
Date: October 1, 2006
Creator: Baker, John D. & McGrath, Christopher A.
Partner: UNT Libraries Government Documents Department
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Final Technical Progress Report Long Term Risk from Actinides in the Environment: Modes of Mobility

Description: The key source of uncertainty in assessing actinide mobility is the relative importance of transport by: (1) wind erosion, (2) water erosion, and (3) vertical migration. Each of these three processes depends on several environmental factors and they compete with one another. A scientific assessment of the long-term risks associated with actinides in surface soils depends on better quantifying each of these three modes of mobility. The objective from our EMSP study was to quantify the mobility o… more
Date: March 22, 2002
Creator: Kirchner, Thomas B.
Partner: UNT Libraries Government Documents Department
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Studies of vibrational properties in Ga stabilized delta-Pu by extended X-ray absorption fine structure

Description: Temperature dependent extended x-ray absorption fine structure (EXAFS) spectra were measured for a 3.3 at. % Ga stabilized Pu alloy over the range T= 20 - 300 K. EXAFS data were acquired at both the Ga K-edge and the Pu L{sub III} edge. Curve-fits were performed to the first shell interactions to obtain pair-distance distribution widths, {sigma}, as a function of temperature. The temperature dependence of {sigma}(T) was accurately modeled using a correlated-Debye model for the lattice vibration… more
Date: February 14, 2002
Creator: Allen, P. G.; Henderson, A. L.; Sylwester, E. R.; Turchi, P. E. A.; Shen, T. H.; Gallegos, G. F. et al.
Partner: UNT Libraries Government Documents Department
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United States Transuranium and Uranium Registries. Annual report February 1, 2000--January 31, 2001

Description: The United States Transuranium and Uranium Registries (USTUR) comprise a human tissue research program studying the deposition, biokinetics and dosimetry of the actinide elements in humans with the primary goals of providing data fundamental to the verification, refinement, or future development of radiation protection standards for these and other radionuclides, and of determining possible bioeffects on both a macro and subcellular level attributable to exposure to the actinides. This report c… more
Date: July 1, 2001
Creator: Ehrhart, Susan M. (ed.) & Filipy, Ronald E. (ed.)
Partner: UNT Libraries Government Documents Department
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United States Transuranium and Uranium Registries. Annual report October 1, 1994 - September 30, 1995

Description: The United States Transuranium and Uranium Registries (USTUR) comprise a human tissue research program studying the deposition, biokinetics and dosimetry of the actinide elements in humans with the primary goals of providing data fundamental to the verification, refinement, or future development of radiation protection standards for these and other radionuclides, and of determining possible bioeffects on both a macro and subcellular level attributable to exposure to the actinides. This report c… more
Date: July 1, 1996
Creator: Kathren, R. L.; Harwick, Lynn A. & Markel, M. June
Partner: UNT Libraries Government Documents Department
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