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Sample records for minor actinides disposition

  1. PF-4 actinide disposition strategy

    SciTech Connect

    Margevicius, Robert W

    2010-05-28

    The dwindling amount of Security Category I processing and storage space across the DOE Complex has driven the need for more effective storage of nuclear materials at LANL's Plutonium Facility's (PF-4's) vault. An effort was begun in 2009 to create a strategy, a roadmap, to identify all accountable nuclear material and determine their disposition paths, the PF-4 Actinide Disposition Strategy (PADS). Approximately seventy bins of nuclear materials with similar characteristics - in terms of isotope, chemical form, impurities, disposition location, etc. - were established in a database. The ultimate disposition paths include the material to remain at LANL, disposition to other DOE sites, and disposition to waste. If all the actions described in the document were taken, over half of the containers currently in the PF-4 vault would been eliminated. The actual amount of projected vault space will depend on budget and competing mission requirements, however, clearly a significant portion of the current LANL inventory can be either dispositioned or consolidated.

  2. Separation of Minor Actinides from Lanthanides by Dithiophosphinic Acid Extractants

    SciTech Connect

    D. R. Peterman; M. R. Greenhalgh; R. D. Tillotson; J. R. Klaehn; M. K. Harrup; T. A. Luther; J. D. Law; L. M. Daniels

    2008-09-01

    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 an innovative synthetic pathway yielding new regiospecific dithiophosphinic acid (DPAH) extractants. The synthesis provides DPAH derivatives that can address the issues concerning minor actinide separation and extractant stability. For this work, two new symmetric DPAH extractants have been prepared. The use of these extractants for the separation of minor actinides from lanthanides will be discussed.

  3. Minor Actinides Recycling in PWRs

    SciTech Connect

    Delpech, M.; Golfier, H.; Vasile, A.; Varaine, F.; Boucher, L.; Greneche, D.

    2006-07-01

    Recycling of minor actinides in current and near future PWR is considered as one of the options of the general waste management strategy. This paper presents the analysis of this option both from the core physics and fuel cycle point of view. A first indicator of the efficiency of different neutron spectra for transmutation purposes is the capture to fission cross sections ratio which is less favourable by a factor between 5 to 10 in PWRs compared to fast reactors. Another indicator presented is the production of high ranking isotopes like Curium, Berkelium or Californium in the thermal or epithermal spectrum conditions of PWR cores by successive neutron captures. The impact of the accumulation of this elements on the fabrication process of such PWR fuels strongly penalizes this option. The main constraint on minor actinides loadings in PWR (or fast reactors) fuels are related to their direct impact (or the impact of their transmutation products) on the reactivity coefficients, the reactivity control means and the core kinetics parameters. The main fuel cycle physical parameters like the neutron source, the alpha decay power, the gamma and neutrons dose rate and the criticality aspects are also affected. Recent neutronic calculations based on a reference core of the Evolutionary Pressurized Reactor (EPR), indicates typical maximum values of 1 % loadings. Different fuel design options for minor actinides transmutation purposes in PWRs are presented: UOX and MOX, homogeneous and heterogeneous assemblies. In this later case, Americium loading is concentrated in specific pins of a standard UOX assembly. Recycling of Neptunium in UOX and MOX fuels was also studied to improve the proliferation resistance of the fuel. The impact on the core physics and penalties on Uranium enrichment were underlined in this case. (authors)

  4. BWR Assembly Optimization for Minor Actinide Recycling

    SciTech Connect

    G. Ivan Maldonado; John M. Christenson; J.P. Renier; T.F. Marcille; J. Casal

    2010-03-22

    The Primary objective of the proposed project is to apply and extend the latest advancements in LWR fuel management optimization to the design of advanced boiling water reactor (BWR) fuel assemblies specifically for the recycling of minor actinides (MAs).

  5. Plutonium and ''minor'' actinides: safe sequestration [rapid communication

    NASA Astrophysics Data System (ADS)

    Ewing, Rodney C.

    2005-01-01

    The actinides exhibit a number of unique chemical and nuclear properties. Of particular interest are the man-made actinides (Np, Pu, Cm and Am) that are produced in significant enough quantities that they are a source of energy in fission reactions, a source of fissile material for nuclear weapons and of environmental concern because of their long half-lives and radiotoxicity. During the past 50 yr, over 1400 mT of Pu and substantial quantities of the "minor" actinides, such as Np, Am and Cm, have been generated in nuclear reactors. There are two basic strategies for the disposition of these elements: (1) to "burn" or transmute the actinides using nuclear reactors or accelerators; (2) to "sequester" the actinides in chemically durable, radiation-resistant materials that are suitable for geologic disposal. There has been substantial interest in the use of isometric pyrochlore, A 2B 2O 7 (A=rare earths; B=Ti, Zr, Sn and Hf), for the immobilization of actinides, particularly plutonium. Systematic studies of rare-earth pyrochlores have led to the discovery that certain compositions (B=Zr, Hf) are stable to very high doses of α-decay event damage. The radiation stability of these compositions is closely related to the structural distortions that occur for specific pyrochlore compositions and the electronic structure of the B-site cation. This understanding provides the basis for designing materials for the safe, long-term immobilization and sequestration of actinides.

  6. Disposition of actinides released from high-level waste glass

    SciTech Connect

    Ebert, W.L.; Bates, J.K.; Buck, E.C.; Gong, M.; Wolf, S.F.

    1994-05-01

    A series of static leach tests was conducted using glasses developed for vitrifying tank wastes at the Savannah River Site to monitor the disposition of actinide elements upon corrosion of the glasses. In these tests, glasses produced from SRL 131 and SRL 202 frits were corroded at 90{degrees}C in a tuff groundwater. Tests were conducted using crushed glass at different glass surface area-to-solution volume (S/V) ratios to assess the effect of the S/V on the solution chemistry, the corrosion of the glass, and the disposition of actinide elements. Observations regarding the effects of the S/V on the solution chemistry and the corrosion of the glass matrix have been reported previously. This paper highlights the solution analyses performed to assess how the S/V used in a static leach test affects the disposition of actinide elements between fractions that are suspended or dissolved in the solution, and retained by the altered glass or other materials.

  7. Detailed calculations of minor actinide transmutation in a fast reactor

    SciTech Connect

    Takeda, Toshikazu

    2015-12-31

    The transmutation of minor actinides in a fast reactor is investigated by a new method to investigate the transmutation behavior of individual minor actinides. It is found that Np-237 and Am-241 mainly contributes to the transmutation rate though the transmutation behaviors are very different.

  8. Detailed calculations of minor actinide transmutation in a fast reactor

    NASA Astrophysics Data System (ADS)

    Takeda, Toshikazu

    2015-12-01

    The transmutation of minor actinides in a fast reactor is investigated by a new method to investigate the transmutation behavior of individual minor actinides. It is found that Np-237 and Am-241 mainly contributes to the transmutation rate though the transmutation behaviors are very different.

  9. Separating the Minor Actinides Through Advances in Selective Coordination Chemistry

    SciTech Connect

    Lumetta, Gregg J.; Braley, Jenifer C.; Sinkov, Sergey I.; Carter, Jennifer C.

    2012-08-22

    This report describes work conducted at the Pacific Northwest National Laboratory (PNNL) in Fiscal Year (FY) 2012 under the auspices of the Sigma Team for Minor Actinide Separation, funded by the U.S. Department of Energy Office of Nuclear Energy. Researchers at PNNL and Argonne National Laboratory (ANL) are investigating a simplified solvent extraction system for providing a single-step process to separate the minor actinide elements from acidic high-level liquid waste (HLW), including separating the minor actinides from the lanthanide fission products.

  10. Accuracy Improvement of Neutron Nuclear Data on Minor Actinides

    NASA Astrophysics Data System (ADS)

    Harada, Hideo; Iwamoto, Osamu; Iwamoto, Nobuyuki; Kimura, Atsushi; Terada, Kazushi; Nakao, Taro; Nakamura, Shoji; Mizuyama, Kazuhito; Igashira, Masayuki; Katabuchi, Tatsuya; Sano, Tadafumi; Takahashi, Yoshiyuki; Takamiya, Koichi; Pyeon, Cheol Ho; Fukutani, Satoshi; Fujii, Toshiyuki; Hori, Jun-ichi; Yagi, Takahiro; Yashima, Hiroshi

    2015-05-01

    Improvement of accuracy of neutron nuclear data for minor actinides (MAs) and long-lived fission products (LLFPs) is required for developing innovative nuclear system transmuting these nuclei. In order to meet the requirement, the project entitled as "Research and development for Accuracy Improvement of neutron nuclear data on Minor ACtinides (AIMAC)" has been started as one of the "Innovative Nuclear Research and Development Program" in Japan at October 2013. The AIMAC project team is composed of researchers in four different fields: differential nuclear data measurement, integral nuclear data measurement, nuclear chemistry, and nuclear data evaluation. By integrating all of the forefront knowledge and techniques in these fields, the team aims at improving the accuracy of the data. The background and research plan of the AIMAC project are presented.

  11. The EBR-II X501 Minor Actinide Burning Experiment

    SciTech Connect

    M. K. Meyer; S. L. Hayes; W. J. Carmack; H. Tsai

    2009-07-01

    The X501 experiment was conducted in EBR-II as part of the IFR (Integral Fast Reactor) program to demonstrate minor actinide burning through the use of a homogeneous recycle scheme. The X501 subassembly contained two metallic fuel elements loaded with relatively small quantities of americium and neptunium. Interest in the behavior of minor actinides (MA) during fuel irradiation has prompted further examination of existing X501 data, and generation of new data where needed in support of the U.S. waste transmutation effort. The X501 experiment is one of the few minor actinide-bearing fuel irradiation tests conducted worldwide and knowledge can be gained by understanding the changes in fuel behavior due to addition of MA’s. Of primary interest are the affect of the MA’s on fuel-cladding-chemical-interaction, and the redistribution behavior of americium. The quantity of helium gas release from the fuel and any effects of helium on fuel performance are also of interest. It must be stressed that information presented at this time is based on the limited PIE conducted in 1995-1996, and currently represents a set of observations rather than a complete understanding of fuel behavior. This paper provides a summary of the X501 fabrication, characterization, irradiation, and post irradiation examination.

  12. The EBR-II X501 Minor Actinide Burning Experiment

    SciTech Connect

    Jon Carmack; S. L. Hayes; M. K. Meyer; H. Tsai

    2008-06-01

    The X501 experiment was conducted in EBR-II as part of the IFR (Integral Fast Reactor) program to demonstrate minor actinide burning through the use of a homogeneous recycle scheme. The X501 subassembly contained two metallic fuel elements loaded with relatively small quantities of americium and neptunium. Interest in the behavior of minor actinides (MA) during fuel irradiation has prompted further examination of existing X501 data, and generation of new data where needed in support of the U.S. waste transmutation effort. The X501 experiment is one of the few minor actinide-bearing fuel irradiation tests conducted worldwide and knowledge can be gained by understanding the changes in fuel behavior due to addition of MA’s. Of primary interest are the affect of the MA’s on fuel-cladding-chemical-interaction, and the redistribution behavior of americium. The quantity of helium gas release from the fuel and any effects of helium on fuel performance are also of interest. It must be stressed that information presented at this time is based on the limited PIE conducted in 1995-1996, and currently represents a set of observations rather than a complete understanding of fuel behavior.

  13. Plutonium and minor actinides utilization in Thorium molten salt reactor

    SciTech Connect

    Waris, Abdul; Aji, Indarta K.; Novitrian,; Kurniadi, Rizal; Su'ud, Zaki

    2012-06-06

    FUJI-12 reactor is one of MSR systems that proposed by Japan. The original FUJI-12 design considers Th/{sup 233}U or Th/Pu as main fuel. In accordance with the currently suggestion to stay away from the separation of Pu and minor actinides (MA), in this study we evaluated the utilization of Pu and MA in FUJI-12. The reactor grade Pu was employed in the present study as a small effort of supporting THORIMS-NES scenario. The result shows that the reactor can achieve its criticality with the Pu and MA composition in the fuel of 5.96% or more.

  14. Plutonium and minor actinides utilization in Thorium molten salt reactor

    NASA Astrophysics Data System (ADS)

    Waris, Abdul; Aji, Indarta K.; Novitrian, Kurniadi, Rizal; Su'ud, Zaki

    2012-06-01

    FUJI-12 reactor is one of MSR systems that proposed by Japan. The original FUJI-12 design considers Th/233U or Th/Pu as main fuel. In accordance with the currently suggestion to stay away from the separation of Pu and minor actinides (MA), in this study we evaluated the utilization of Pu and MA in FUJI-12. The reactor grade Pu was employed in the present study as a small effort of supporting THORIMS-NES scenario. The result shows that the reactor can achieve its criticality with the Pu & MA composition in the fuel of 5.96% or more.

  15. Dynamics of Critical Dedicated Cores for Minor Actinide Transmutation

    SciTech Connect

    Massara, S.; Tommasi, J.; Vanier, M.; Koeberl, O.

    2005-02-15

    Fast spectrum minor actinide (MA) burner designs, with high minor actinide loads and consumptions, have been assessed. As reactivity and kinetic coefficients are poor in such cores (low delayed neutron fraction and Doppler feedback, high coolant void coefficient), special attention has been paid to their dynamic behavior during transient conditions. A dynamics code, MAT4 DYN, has been expressly developed to study loss-of-flow, reactivity insertion, and loss-of-coolant accidents. It takes into account two fuel geometries (cylindrical and spherical) and two thermal-hydraulics models for the coolant (incompressible for liquid metals and compressible for helium).Three nitride-fuel configurations are analyzed according to their coolant: sodium and lead (both with pin fuel) and helium (with particle fuel). Dynamics calculations show that if the fuel nature is appropriately chosen, with sufficient margins during transients, then this can counterbalance the poor reactivity coefficients for liquid-metal-cooled cores, thus proving the interest of this kind of concept. On the other hand, the gas-cooled core dynamics is very badly affected by the high value of the helium void coefficient in a hard spectrum, this effect being amplified by the very low thermal inertia of the fuel particles. Hence, concepts other than a particle-bed fuel should be investigated for a helium-cooled fast-spectrum MA burner.

  16. The EBR-II X501 Minor Actinide Burning Experiment

    SciTech Connect

    W. J. Carmack; M. K. Meyer; S. L. Hayes; H. Tsai

    2008-01-01

    The X501 experiment was conducted in EBR II as part of the Integral Fast Reactor program to demonstrate minor actinide burning through the use of a homogeneous recycle scheme. The X501 subassembly contained two metallic fuel elements loaded with relatively small quantities of americium and neptunium. Interest in the behavior of minor actinides (MA) during fuel irradiation has prompted further examination of existing X501 data and generation of new data where needed in support of the U.S. waste transmutation effort. The X501 experiment is one of the few MA bearing fuel irradiation tests conducted worldwide, and knowledge can be gained by understanding the changes in fuel behavior due to addition of MAs. Of primary interest are the effect of the MAs on fuel cladding chemical interaction and the redistribution behavior of americium. The quantity of helium gas release from the fuel and any effects of helium on fuel performance are also of interest. It must be stressed that information presented at this time is based on the limited PIE conducted in 1995–1996 and, currently, represents a set of observations rather than a complete understanding of fuel behavior. This report provides a summary of the X501 fabrication, characterization, irradiation, and post irradiation examination.

  17. A Heterogeneous Sodium Fast Reactor Designed to Transmute Minor Actinide Actinide Waste Isotopes into Plutonium Fuel

    SciTech Connect

    Samuel E. Bays

    2011-02-01

    An axial heterogeneous sodium fast reactor design is developed for converting minor actinide waste isotopes into plutonium fuel. The reactor design incorporates zirconium hydride moderating rods in an axial blanket above the active core. The blanket design traps the active core’s axial leakage for the purpose of transmuting Am-241 into Pu-238. This Pu-238 is then co-recycled with the spent driver fuel to make new driver fuel. Because Pu-238 is significantly more fissile than Am-241 in a fast neutron spectrum, the fissile worth of the initial minor actinide material is upgraded by its preconditioning via transmutation in the axial targets. Because, the Am-241 neutron capture worth is significantly stronger in a moderated epithermal spectrum than the fast spectrum, the axial targets serve as a neutron trap which recovers the axial leakage lost by the active core. The sodium fast reactor proposed by this work is designed as an overall transuranic burner. Therefore, a low transuranic conversion ratio is achieved by a degree of core flattening which increases axial leakage. Unlike a traditional “pancake” design, neutron leakage is recovered by the axial target/blanket system. This heterogeneous core design is constrained to have sodium void and Doppler reactivity worth similar to that of an equivalent homogeneous design. Because minor actinides are irradiated only once in the axial target region; elemental partitioning is not required. This fact enables the use of metal targets with electrochemical reprocessing. Therefore, the irradiation environment of both drivers and targets was constrained to ensure applicability of the established experience database for metal alloy sodium fast reactor fuels.

  18. ENHANCING ADVANCED CANDU PROLIFERATION RESISTANCE FUEL WITH MINOR ACTINIDES

    SciTech Connect

    Gray S. Chang

    2010-05-01

    The advanced nuclear system will significantly advance the science and technology of nuclear energy systems and to enhance the spent fuel proliferation resistance. Minor actinides (MA) are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. MAs can play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. In this work, an Advanced CANDU Reactor (ACR) fuel unit lattice cell model with 43 UO2 fuel rods will be used to investigate the effectiveness of a Minor Actinide Reduction Approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance. The main MARA objective is to increase the 238Pu / Pu isotope ratio by using the transuranic nuclides (237Np and 241Am) in the high burnup fuel and thereby increase the proliferation resistance even for a very low fuel burnup. As a result, MARA is a very effective approach to enhance the proliferation resistance for the on power refueling ACR system nuclear fuel. The MA transmutation characteristics at different MA loadings were compared and their impact on neutronics criticality assessed. The concept of MARA, significantly increases the 238Pu/Pu ratio for proliferation resistance, as well as serves as a burnable absorber to hold-down the initial excess reactivity. It is believed that MARA can play an important role in atoms for peace and the intermediate term of nuclear energy reconnaissance.

  19. Enhancing VVER Annular Proliferation Resistance Fuel with Minor Actinides

    SciTech Connect

    G. S. Chang

    2007-06-01

    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 systems that offer much improved fuel utilization and proliferation resistance, along with continued advances in operational safety. The challenges are solving the energy needs of the world, protection against nuclear proliferation, the problem of nuclear waste, and the global environmental problem. To reduce the spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu and 240Pu isotopes ratio to enhance the proliferation resistance, (b) use of transuranic nuclides (237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope 238Pu /Pu ratio. For future advanced nuclear systems, the minor actinides are viewed more as a resource to be recycled, or transmuted to less hazardous and possibly more useful forms, rather than simply as a waste stream to be disposed of in expensive repository facilities. In this paper, a typical pressurized water reactor (PWR) VVER-1000 annular fuel unit lattice cell model with UO2 fuel pins will be used to investigate the effectiveness of minor actinide reduction approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance. We concluded that the concept of MARA, involves the use of transuranic nuclides (237Np and/or 241Am), can not only drastically

  20. Proliferation Resistance Evaluation of ACR-1000 Fuel with Minor Actinides

    SciTech Connect

    Gray S. Chang

    2008-09-01

    The Global Nuclear Energy Partnership (GNEP) program is to significantly advance the science and technology of nuclear energy systems and to enhance the spent fuel proliferation resistance. It consists of both innovative nuclear reactors and innovative research in separation and transmutation. The merits of nuclear energy are high-density energy, with 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 light water reactors (LWRs) as well as the longer-term development of new nuclear energy systems that offer much improved fuel utilization and proliferation resistance, along with continued advances in operational safety. For future advanced nuclear systems, minor actinides (MA) are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. MAs can play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. In this work, an Advanced CANDU Reactor (ACR) fuel unit lattice cell model with 43 UO2 fuel rods will be used to investigate the effectiveness of a Minor Actinide Reduction Approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance. The main MARA objective is to increase the 238Pu / Pu isotope ratio by using the transuranic nuclides (237Np and 241Am) in the high burnup fuel and thereby increase the proliferation resistance even for a very low fuel burnup. As a result, MARA is a very effective approach to enhance the proliferation resistance for the on power refueling ACR system nuclear fuel. The MA transmutation characteristics at different MA loadings were compared and their impact on neutronics

  1. Enhancing BWR Proliferation Resistance Fuel with Minor Actinides

    SciTech Connect

    Gray S. Chang

    2009-03-01

    To reduce spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced light water reactor- LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu isotopes ratio to enhance the proliferation resistance, and (b) use of transuranic nuclides (237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope ratio of 238Pu/Pu. For future advanced nuclear systems, minor actinides (MA) are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. As a result, MAs play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. In the study, a typical boiling water reactor (BWR) fuel unit lattice cell model with UO2 fuel pins will be used to investigate the effectiveness of minor actinide reduction approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance in the intermediate-term goal for future nuclear energy systems. To account for the water coolant density variation from the bottom (0.76 g/cm3) to the top (0.35 g/cm3) of the core, the axial coolant channel and fuel pin were divided to 24 nodes. The MA transmutation characteristics at different elevations were compared and their impact on neutronics criticality discussed. The concept of MARA, which involves the use of transuranic nuclides (237Np and/or 241Am), significantly increases the 238Pu/Pu ratio for proliferation resistance, as well as serves as a burnable absorber to hold-down the initial excess reactivity. It is believed that MARA can play an important role in atoms

  2. Enhancing BWR proliferation resistance fuel with minor actinides

    NASA Astrophysics Data System (ADS)

    Chang, Gray S.

    2009-03-01

    To reduce spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced light water reactor- LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu isotopes ratio to enhance the proliferation resistance, and (b) use of transuranic nuclides ( 237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope ratio of 238Pu/Pu. For future advanced nuclear systems, minor actinides (MA) are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. As a result, MAs play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. In the study, a typical boiling water reactor (BWR) fuel unit lattice cell model with UO 2 fuel pins will be used to investigate the effectiveness of minor actinide reduction approach (MARA) for enhancing proliferation resistance and improving the fuel cycle performance in the intermediate-term goal for future nuclear energy systems. To account for the water coolant density variation from the bottom (0.76 g/cm 3) to the top (0.35 g/cm 3) of the core, the axial coolant channel and fuel pin were divided to 24 nodes. The MA transmutation characteristics at different elevations were compared and their impact on neutronics criticality discussed. The concept of MARA, which involves the use of transuranic nuclides ( 237Np and/or 241Am), significantly increases the 238Pu/Pu ratio for proliferation resistance, as well as serves as a burnable absorber to hold-down the initial excess reactivity. It is believed that MARA can play an important role in

  3. Enhancing BWR Proliferation Resistance Fuel with Minor Actinides

    SciTech Connect

    Gray S. Chang

    2008-07-01

    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. It consists of both innovative nuclear reactors and innovative research in separation and transmutation. To accomplish these goals, international cooperation is very important and public acceptance is crucial. The merits of nuclear energy are high-density energy, with 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 light water reactors (LWRs) as well as the longer-term development of new nuclear energy systems that offer much improved fuel utilization and proliferation resistance, along with continued advances in operational safety. The challenges are solving the energy needs of the world, protection against nuclear proliferation, the problem of nuclear waste, and the global environmental problem. To reduce spent fuel for storage and enhance the proliferation resistance for the intermediate-term, there are two major approaches (a) increase the discharged spent fuel burnup in the advanced LWR (Gen-III Plus), which not only can reduce the spent fuel for storage, but also increase the 238Pu and 240Pu isotopes ratio to enhance the proliferation resistance, and (b) use of transuranic nuclides (237Np and 241Am) in the high burnup fuel, which can drastically increase the proliferation resistance isotope ratio of 238Pu /Pu. For future advanced nuclear systems, the minor actinides (MA) are viewed more as a resource to be recycled, or transmuted to less hazardous and possibly more useful forms, rather than simply as a waste stream to be disposed of in expensive repository facilities. As a result, MAs play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the

  4. Minor Actinides Loading Optimization for Proliferation Resistant Fuel Design - BWR

    SciTech Connect

    G. S. Chang; Hongbin Zhang

    2009-09-01

    One approach to address the United States Nuclear Power (NP) 2010 program for the advanced light water reactor (LWR) (Gen-III+) intermediate-term spent fuel disposal need is to reduce spent fuel storage volume while enhancing proliferation resistance. One proposed solution includes increasing burnup of the discharged spent fuel and mixing minor actinide (MA) transuranic nuclides (237Np and 241Am) in the high burnup fuel. Thus, we can reduce the spent fuel volume while increasing the proliferation resistance by increasing the isotopic ratio of 238Pu/Pu. For future advanced nuclear systems, MAs are viewed more as a resource to be recycled, and transmuted to less hazardous and possibly more useful forms, rather than simply disposed of as a waste stream in an expensive repository facility. MAs play a much larger part in the design of advanced systems and fuel cycles, not only as additional sources of useful energy, but also as direct contributors to the reactivity control of the systems into which they are incorporated. A typical boiling water reactor (BWR) fuel unit lattice cell model with UO2 fuel pins will be used to investigate the effectiveness of adding MAs (237Np and/or 241Am) to enhance proliferation resistance and improve fuel cycle performance for the intermediate-term goal of future nuclear energy systems. However, adding MAs will increase plutonium production in the discharged spent fuel. In this work, the Monte-Carlo coupling with ORIGEN-2.2 (MCWO) method was used to optimize the MA loading in the UO2 fuel such that the discharged spent fuel demonstrates enhanced proliferation resistance, while minimizing plutonium production. The axial averaged MA transmutation characteristics at different burnup were compared and their impact on neutronics criticality and the ratio of 238Pu/Pu discussed.

  5. Minor actinide transmutation in thorium and uranium matrices in heavy water moderated reactors

    SciTech Connect

    Bhatti, Zaki; Hyland, B.; Edwards, G.W.R.

    2013-07-01

    The irradiation of Th{sup 232} breeds fewer of the problematic minor actinides (Np, Am, Cm) than the irradiation of U{sup 238}. This characteristic makes thorium an attractive potential matrix for the transmutation of these minor actinides, as these species can be transmuted without the creation of new actinides as is the case with a uranium fuel matrix. Minor actinides are the main contributors to long term decay heat and radiotoxicity of spent fuel, so reducing their concentration can greatly increase the capacity of a long term deep geological repository. Mixing minor actinides with thorium, three times more common in the Earth's crust than natural uranium, has the additional advantage of improving the sustainability of the fuel cycle. In this work, lattice cell calculations have been performed to determine the results of transmuting minor actinides from light water reactor spent fuel in a thorium matrix. 15-year-cooled group-extracted transuranic elements (Np, Pu, Am, Cm) from light water reactor (LWR) spent fuel were used as the fissile component in a thorium-based fuel in a heavy water moderated reactor (HWR). The minor actinide (MA) transmutation rates, spent fuel activity, decay heat and radiotoxicity, are compared with those obtained when the MA were mixed instead with natural uranium and taken to the same burnup. Each bundle contained a central pin containing a burnable neutron absorber whose initial concentration was adjusted to have the same reactivity response (in units of the delayed neutron fraction β) for coolant voiding as standard NU fuel. (authors)

  6. Plutonium and minor actinide utilisation in a pebble-bed high temperature reactor

    SciTech Connect

    Petrov, B. Y.; Kuijper, J. C.; Oppe, J.; De Haas, J. B. M.

    2012-07-01

    This paper contains results of the analysis of the pebble-bed high temperature gas-cooled PUMA reactor loaded with plutonium and minor actinide (Pu/MA) fuel. Starting from knowledge and experience gained in the Euratom FP5 projects HTR-N and HTR-N1, this study aims at demonstrating the potential of high temperature reactors to utilize or transmute Pu/MA fuel. The work has been performed within the Euratom FP6 project PUMA. A number of different fuel types and fuel configurations have been analyzed and compared with respect to incineration performance and safety-related reactor parameters. The results show the excellent plutonium and minor actinide burning capabilities of the high temperature reactor. The largest degree of incineration is attained in the case of an HTR fuelled by pure plutonium fuel as it remains critical at very deep burnup of the discharged pebbles. Addition of minor actinides to the fuel leads to decrease of the achievable discharge burnup and therefore smaller fraction of actinides incinerated during reactor operation. The inert-matrix fuel design improves the transmutation performance of the reactor, while the 'wallpaper' fuel does not have advantage over the standard fuel design in this respect. After 100 years of decay following the fuel discharge, the total amount of actinides remains almost unchanged for all of the fuel types considered. Among the plutonium isotopes, only the amount of Pu-241 is reduced significantly due to its relatively short half-life. (authors)

  7. MINOR ACTINIDE SEPARATIONS USING ION EXCHANGERS OR IONIC LIQUIDS

    SciTech Connect

    Hobbs, D.; Visser, A.; Bridges, N.

    2011-09-20

    This project seeks to determine if (1) inorganic-based ion exchange materials or (2) electrochemical methods in ionic liquids can be exploited to provide effective Am and Cm separations. Specifically, we seek to understand the fundamental structural and chemical factors responsible for the selectivity of inorganic-based ion-exchange materials for actinide and lanthanide ions. Furthermore, we seek to determine whether ionic liquids can serve as the electrolyte that would enable formation of higher oxidation states of Am and other actinides. Experiments indicated that pH, presence of complexants and Am oxidation state exhibit significant influence on the uptake of actinides and lanthanides by layered sodium titanate and hybrid zirconium and tin phosphonate ion exchangers. The affinity of the ion exchangers increased with increasing pH. Greater selectivity among Ln(III) ions with sodium titanate materials occurs at a pH close to the isoelectric potential of the ion exchanger. The addition of DTPA decreased uptake of Am and Ln, whereas the addition of TPEN generally increases uptake of Am and Ln ions by sodium titanate. Testing confirmed two different methods for producing Am(IV) by oxidation of Am(III) in ionic liquids (ILs). Experimental results suggest that the unique coordination environment of ionic liquids inhibits the direct electrochemical oxidation of Am(III). The non-coordinating environment increases the oxidation potential to a higher value, while making it difficult to remove the inner coordination of water. Both confirmed cases of Am(IV) were from the in-situ formation of strong chemical oxidizers.

  8. 25 CFR 11.1111 - Minor-in-need-of-care dispositional hearing.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Minor-in-need-of-care dispositional hearing. 11.1111 Section 11.1111 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1111...

  9. 25 CFR 11.1111 - Minor-in-need-of-care dispositional hearing.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 25 Indians 1 2014-04-01 2014-04-01 false Minor-in-need-of-care dispositional hearing. 11.1111 Section 11.1111 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1111...

  10. 25 CFR 11.1111 - Minor-in-need-of-care dispositional hearing.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Minor-in-need-of-care dispositional hearing. 11.1111 Section 11.1111 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1111...

  11. 25 CFR 11.1111 - Minor-in-need-of-care dispositional hearing.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Minor-in-need-of-care dispositional hearing. 11.1111 Section 11.1111 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1111...

  12. 25 CFR 11.1111 - Minor-in-need-of-care dispositional hearing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Minor-in-need-of-care dispositional hearing. 11.1111 Section 11.1111 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1111...

  13. Assessment of SFR fuel pin performance codes under advanced fuel for minor actinide transmutation

    SciTech Connect

    Bouineau, V.; Lainet, M.; Chauvin, N.; Pelletier, M.

    2013-07-01

    Americium is a strong contributor to the long term radiotoxicity of high activity nuclear waste. Transmutation by irradiation in nuclear reactors of long-lived nuclides like {sup 241}Am is, therefore, an option for the reduction of radiotoxicity and residual power packages as well as the repository area. In the SUPERFACT Experiment four different oxide fuels containing high and low concentrations of {sup 237}Np and {sup 241}Am, representing the homogeneous and heterogeneous in-pile recycling concepts, were irradiated in the PHENIX reactor. The behavior of advanced fuel materials with minor actinide needs to be fully characterized, understood and modeled in order to optimize the design of this kind of fuel elements and to evaluate its performances. This paper assesses the current predictability of fuel performance codes TRANSURANUS and GERMINAL V2 on the basis of post irradiation examinations of the SUPERFACT experiment for pins with low minor actinide content. Their predictions have been compared to measured data in terms of geometrical changes of fuel and cladding, fission gases behavior and actinide and fission product distributions. The results are in good agreement with the experimental results, although improvements are also pointed out for further studies, especially if larger content of minor actinide will be taken into account in the codes. (authors)

  14. Minor Actinides, Major Challenges, the Needs for and Benefits of International Collaboration

    NASA Astrophysics Data System (ADS)

    Plompen, A. J. M.

    2014-04-01

    The role of experiments for the determination of minor actinide nuclear data is presented as essential to meet the tight uncertainties requirements derived by sensitivity analyses for innovative systems designed to significantly reduce the amount of high level nuclear waste. Recent, ongoing and planned experiments are highlighted emphasizing international collaboration and the European context. Specifically, the role of the MANREAD CRP, the European projects ANDES, ERINDA and EURFRAT, and the NEA databank and WPEC subgroups will be addressed. For 241Am capture and 240Pu fission are used to illustrate the generic situation with minor actinide experimental data and the discrepancy between achieved and target uncertainties. The importance of new high quality experiments, high quality reporting, diversity, new techniques, methods and facilities is stressed.

  15. Determination of Minor Actinides Fission Cross Sections by Means of Transfer Reactions

    NASA Astrophysics Data System (ADS)

    Aiche, M.; Barreau, G.; Boyer, S.; Czajkowski, S.; Dassié, D.; Grosjean, C.; Guiral, A.; Haas, B.; Jurado, B.; Osmanov, B.; Bauge, E.; Petit, M.; Berthoumieux, E.; Gunsing, F.; Perrot, L.; Theisen, C.; Michel-Sendis, F.; Billebaud, A.; Wilson, J. N.; Ahmad, I.; Greene, J. P.; Janssens, R. V. F.

    2006-04-01

    An inventive method that allows to determine neutron-induced cross sections of very short-lived minor actinides is presented. We have successfully applied this method, based on the use of transfer reactions, to 233Pa, a key nucleus in the 232Th-233U fuel cycle. A recent experiment using this technique has also been performed in order to obtain the neutron-induced fission cross sections of 242, 243, 244Cm and 241Am which are present in the nuclear waste of the current U-Pu fuel cycle. These cross sections are highly relevant for the design of reactors capable to incinerate minor actinides. Preliminary experimental results will be presented.

  16. The technical and economic impact of minor actinide transmutation in a sodium fast reactor

    SciTech Connect

    Gautier, G. M.; Morin, F.; Dechelette, F.; Sanseigne, E.; Chabert, C.

    2012-07-01

    Within the frame work of the French National Act of June 28, 2006 pertaining to the management of high activity, long-lived radioactive waste, one of the proposed processes consists in transmuting the Minor Actinides (MA) in the radial blankets of a Sodium Fast Reactor (SFR). With this option, we may assess the additional cost of the reactor by comparing two SFR designs, one with no Minor Actinides, and the other involving their transmutation. To perform this exercise, we define a reference design called SFRref, of 1500 MWe that is considered to be representative of the Reactor System. The SFRref mainly features a pool architecture with three pumps, six loops with one steam generator per loop. The reference core is the V2B core that was defined by the CEA a few years ago for the Reactor System. This architecture is designed to meet current safety requirements. In the case of transmutation, for this exercise we consider that the fertile blanket is replaced by two rows of assemblies having either 20% of Minor Actinides or 20% of Americium. The assessment work is performed in two phases. - The first consists in identifying and quantifying the technical differences between the two designs: the reference design without Minor Actinides and the design with Minor Actinides. The main differences are located in the reactor vessel, in the fuel handling system and in the intermediate storage area for spent fuel. An assessment of the availability is also performed so that the impact of the transmutation can be known. - The second consists in making an economic appraisal of the two designs. This work is performed using the CEA's SEMER code. The economic results are shown in relative values. For a transmutation of 20% of MA in the assemblies (S/As) and a hypothesis of 4 kW allowable for the washing device, there is a large external storage demanding a very long cooling time of the S/As. In this case, the economic impact may reach 5% on the capital part of the Levelized Unit

  17. High-burnup core design using minor actinide-containing metal fuel

    SciTech Connect

    Ohta, Hirokazu; Ogata, Takanari; Obara, T.

    2013-07-01

    A neutronic design study of metal fuel fast reactor (FR) cores is conducted on the basis of an innovative fuel design concept to achieve an extremely high burnup and realize an efficient fuel cycle system. Since it is expected that the burnup reactivity swing will become extremely large in an unprecedented high burnup core, minor actinides (MAs) from light water reactors (LWRs) are added to fresh fuel to improve the core internal conversion. Core neutronic analysis revealed that high burnups of about 200 MWd/kg for a small-scale core and about 300 MWd/kg for a large-scale core can be attained while suppressing the burnup reactivity swing to almost the same level as that of conventional cores with normal burnup. An actinide burnup analysis has shown that the MA consumption ratio is improved to about 60% and that the accumulated MAs originating from LWRs can be efficiently consumed by the high-burnup metal fuel FR. (authors)

  18. Sensitvity and Uncertainty Analysis for a Minor-actinide Transmuter with JENDL-4.0

    NASA Astrophysics Data System (ADS)

    Iwamoto, H.; Nishihara, K.; Sugawara, T.; Tsujimoto, K.

    2014-04-01

    A sensitivity and uncertainty analysis was performed for the minor-actinide transmuter proposed by the Japan Atomic Energy Agency with JENDL-4.0. Analysis with sensitivity coefficients and the JENDL-4.0 covariance data showed that the covariances of the capture cross sections and fission-related parameters of MAs and Pu isotopes have considerable impact on the uncertainties of reactor physics parameters, and covariances of the inelastic scattering cross section of lead-bismuth eutectic (LBE) materials significantly affect the uncertainty of coolant-void reactivity.

  19. Conceptual configurations of an accelerator-driven subcritical system utilizing minor actinides

    SciTech Connect

    Cao, Y.; Gohar, Y.

    2012-07-01

    This paper purposes an Accelerator-Driven Subcritical (ADS) system which utilizes the Minor Actinides (MAs) from the US spent nuclear fuel inventory. A mobile fuel concept with micro-particles suspended in the liquid metal is adopted in the purposed system to avoid difficulties of developing and testing new MAs solid fuel forms. Three ADS configurations were developed and analyzed using the Monte Carlo fuel burnup methodology. The analyses demonstrated the capabilities of the proposed system to utilize the MAs and to dispose of the US spent nuclear fuels. (authors)

  20. Sigma Team for Minor Actinide Separation: PNNL FY 2011 Status Report

    SciTech Connect

    Lumetta, Gregg J.; Braley, Jenifer C.; Sinkov, Sergey I.; Levitskaia, Tatiana G.; Carter, Jennifer C.; Warner, Marvin G.; Pittman, Jonathan W.

    2011-08-13

    This report summarizes work conducted in FY 2011 at PNNL to investigate new methods of separating the minor actinide elements (Am and Cm) from the trivalent lanthanide elements, and separation of Am from Cm. For the former, work focused on a solvent extraction system combining an acidic extractant (HDEHP) with a neutral extractant (CMPO) to form a hybrid solvent extraction system referred to as TRUSPEAK (combining the TRUEX and TALSPEAK processes). For the latter, ligands that strongly bing uranyl ion were investigated for stabilizing corresponding americyl ion.

  1. Study on separation of minor actinides from HLLW with new extractant of TODGA-DHOA/Kerosene

    SciTech Connect

    Ye, Guo-an; Zhu, Wen-bin; Li, Feng-feng; Lin, Ru-shan; Li, Hui-rong

    2013-07-01

    The extraction behavior of U, Np, Pu, Am, rare earth elements and Sr from nitric acid solutions by TODGA/dodecan, DHOA/dodecane and TODGA-DHOA/dodecane were investigated, respectively. Based on experimental results, a separation process was proposed for minor actinide isolation from high level liquid waste (HLLW): the TODGA-DHOA/kerosene system. The multi-stage counter-current cascade experiments were carried out for the purpose by 0.1 mol/l TODGA-1.0 mol/l DHOA/kerosene with miniature mixer- settler contactor rigs (8 stages for extraction, 6 stages for scrubbing, 8 stages for first stripping, 8 stages for second stripping). The results show that the recovery efficiencies of the actinides and lanthanides are more than 99.9%, whereas less than 1% Sr was extracted by 0.1 mol/l TODGA - 1.0 mol/l DHOA/kerosene. The stripping efficiencies of U, Np and Pu are more than 95% in the first stripping step by 0.5 mol/l HNO{sub 3} + 0.5 mol/l AHA(aceto-hydroxamic acid), all of the remained actinides and lanthanides can be stripped by 0.01 mol/l HNO{sub 3} in the second stripping step. 99% Sr was extracted by 0.1 mol/l TODGA/kerosene, so Sr can be recovered efficiently directly from the raffinate by 0.1 mol/l TODGA/kerosene. (authors)

  2. Plutonium incorporation in phosphate and titanate ceramics for minor actinide containment

    NASA Astrophysics Data System (ADS)

    Deschanels, X.; Picot, V.; Glorieux, B.; Jorion, F.; Peuget, S.; Roudil, D.; Jégou, C.; Broudic, V.; Cachia, J. N.; Advocat, T.; Den Auwer, C.; Fillet, C.; Coutures, J. P.; Hennig, C.; Scheinost, A.

    2006-06-01

    Two ceramics, zirconolite and a monazite-brabantite solid solution (MBss) were studied for the immobilization of minor actinides (Np, Am, Cm) produced by reprocessing spent fuel. Monoclinic zirconolite (CaZrTi2O7) is a fluorite derivative structure and is the primary actinide host phase in Synroc (a titanate composite). Monazite (LnPO4, where Ln = La, Ce, Nd, Gd, etc.) is a monoclinic orthophosphate containing trivalent cations, and brabantite (Ca0.5An0.5PO4) is an isostructural monazite compound containing tetravalent cations (An = Th and U). The nominal composition of the ceramics studied in this work is (Ca0.87Pu0.13)Zr(Al0. 26Ti1.74)O7 for zirconolite and (Ca0.09Pu0.09La0.73Th0.09)PO4 for the monazite-brabantite solid solution. These formulas correspond to 10 wt% PuO2 loading in each material. XANES spectroscopy showed that the plutonium is tetravalent in zirconolite and trivalent in MBss. Thorium, another tetravalent cation, can be incorporated at 10 wt% ThO2 in MBss. Aluminum and calcium balance the excess cationic charge resulting from the incorporation of Pu(IV) in zirconolite and Th(IV) in brabantite, respectively. The relative density of the pellets exceeded 90% of theoretical density. The samples exhibited a homogeneous microstructure even if some minor phases, representing less than 2% of the surface area, were detected. The two ceramics are compared in terms of actinide loading, and preliminary results on their long-term behavior are discussed.

  3. Technical and economic assessment of different options for minor actinide transmutation: the French case

    SciTech Connect

    Chabert, C.; Coquelet-Pascal, C.; Saturnin, A.; Mathonniere, G.; Boullis, B.; Warin, D.; Van Den Durpel, L.; Caron-Charles, M.; Garzenne, C.

    2013-07-01

    Studies have been performed to assess the industrial perspectives of partitioning and transmutation of long-lived elements. These studies were carried out in tight connection with GEN-IV systems development. The results include the technical and economic evaluation of fuel cycle scenarios along with different options for optimizing the processes between the minor actinide transmutation in fast neutron reactors, their interim storage and geological disposal of ultimate waste. The results are analysed through several criteria (impacts on waste, on waste repository, on fuel cycle plants, on radiological exposure of workers, on costs and on industrial risks). These scenario evaluations take place in the French context which considers the deployment of the first Sodium-cooled Fast Reactor (SFR) in 2040. 3 management options of minor actinides have been studied: no transmutation, transmutation in SFR and transmutation in an accelerator-driven system (ADS). Concerning economics the study shows that the cost overrun related to the transmutation process could vary between 5 to 9% in SFR and 26 % in the case of ADS.

  4. On the use of moderating material to enhance the feedback coefficients in SFR cores with high minor actinide content

    SciTech Connect

    Merk, B.; Weiss, F. P.

    2012-07-01

    The use of fine distributed moderating material to enhance the feedback effects and to reduce the sodium void effecting sodium cooled fast reactor cores is described. The influence of the moderating material on the neutron spectrum, the power distribution, and the burnup distribution is shown. The consequences of the use of fine distributed moderating material into fuel assemblies with fuel configurations foreseen for minor actinide transmutation is analyzed and the transmutation efficiency is compared. The degradation of the feedback effects due to the insertion of minor actinides and the compensation by the use of moderating materials is discussed. (authors)

  5. Assessment of sensitivity of neutron-physical parameters of fast neutron reactor to purification of reprocessed fuel from minor actinides

    NASA Astrophysics Data System (ADS)

    Cherny, V. A.; Kochetkov, L. A.; Nevinitsa, A. I.

    2013-12-01

    The work is devoted to computational investigation of the dependence of basic physical parameters of fast neutron reactors on the degree of purification of plutonium from minor actinides obtained as a result of pyroelectrochemical reprocessing of spent nuclear fuel and used for manufacturing MOX fuel to be reloaded into the reactors mentioned. The investigations have shown that, in order to preserve such important parameters of a BN-800 type reactor as the criticality, the sodium void reactivity effect, the Doppler effect, and the efficiency of safety rods, it is possible to use the reprocessed fuel without separation of minor actinides for refueling (recharging) the core.

  6. Utilization of Minor Actinides as a Fuel Component for Ultra-Long Life Bhr Configurations: Designs, Advantages and Limitations

    SciTech Connect

    Dr. Pavel V. Tsvetkov

    2009-05-20

    This project assessed the advantages and limitations of using minor actinides as a fuel component to achieve ultra-long life Very High Temperature Reactor (VHTR) configurations. Researchers considered and compared the capabilities of pebble-bed and prismatic core designs with advanced actinide fuels to achieve ultra-long operation without refueling. Since both core designs permit flexibility in component configuration, fuel utilization, and fuel management, it is possible to improve fissile properties of minor actinides by neutron spectrum shifting through configuration adjustments. The project studied advanced actinide fuels, which could reduce the long-term radio-toxicity and heat load of high-level waste sent to a geologic repository and enable recovery of the energy contained in spent fuel. The ultra-long core life autonomous approach may reduce the technical need for additional repositories and is capable to improve marketability of the Generation IV VHTR by allowing worldwide deployment, including remote regions and regions with limited industrial resources. Utilization of minor actinides in nuclear reactors facilitates developments of new fuel cycles towards sustainable nuclear energy scenarios.

  7. Optimisation of composite metallic fuel for minor actinide transmutation in an accelerator-driven system

    NASA Astrophysics Data System (ADS)

    Uyttenhove, W.; Sobolev, V.; Maschek, W.

    2011-09-01

    A potential option for neutralization of minor actinides (MA) accumulated in spent nuclear fuel of light water reactors (LWRs) is their transmutation in dedicated accelerator-driven systems (ADS). A promising fuel candidate dedicated to MA transmutation is a CERMET composite with Mo metal matrix and (Pu, Np, Am, Cm)O 2-x fuel particles. Results of optimisation studies of the CERMET fuel targeting to increasing the MA transmutation efficiency of the EFIT (European Facility for Industrial Transmutation) core are presented. In the adopted strategy of MA burning the plutonium (Pu) balance of the core is minimized, allowing a reduction in the reactivity swing and the peak power form-factor deviation and an extension of the cycle duration. The MA/Pu ratio is used as a variable for the fuel optimisation studies. The efficiency of MA transmutation is close to the foreseen theoretical value of 42 kg TW -1 h -1 when level of Pu in the actinide mixture is about 40 wt.%. The obtained results are compared with the reference case of the EFIT core loaded with the composite CERCER fuel, where fuel particles are incorporated in a ceramic magnesia matrix. The results of this study offer additional information for the EFIT fuel selection.

  8. Study on Equilibrium Characteristics of Thorium-Plutonium-Minor Actinides Mixed Oxides Fuel in PWR

    SciTech Connect

    Waris, A.; Permana, S.; Kurniadi, R.; Su'ud, Z.; Sekimoto, H.

    2010-06-22

    A study on characteristics of thorium-plutonium-minor actinides utilization in the pressurized water reactor (PWR) with the equilibrium burnup model has been conducted. For a comprehensive evaluation, several fuel cycles scenario have been included in the present study with the variation of moderator-to-fuel volume ratio (MFR) of PWR core design. The results obviously exhibit that the neutron spectra grow to be harder with decreasing of the MFR. Moreover, the neutron spectra also turn into harder with the rising number of confined heavy nuclides. The required {sup 233}U concentration for criticality of reactor augments with the increasing of MFR for all heavy nuclides confinement and thorium and uranium confinement in PWR.

  9. Recent progress on minor-actinide-bearing oxide fuel fabrication at CEA Marcoule

    NASA Astrophysics Data System (ADS)

    Lebreton, Florent; Prieur, Damien; Horlait, Denis; Delahaye, Thibaud; Jankowiak, Aurélien; Léorier, Caroline; Jorion, Frédéric; Gavilan, Elisabeth; Desmoulière, François

    2013-07-01

    Partitioning and transmutation (P&T) of minor actinides (MA: americium, neptunium and curium) in fast neutron reactors or accelerator-driven systems is a route envisaged to reduce nuclear waste inventory. Over the years, several modes of P&T were proposed, each being based on the use of dedicated fuels such as inert-matrix fuels, MA-bearing MOX or MA-bearing blankets. In this context, progress on the manufacturing of such fuels is a key-challenge in order to render P&T viable at the industrial scale. Here, MA-bearing oxide fuel fabrication and characterization conducted in the CEA Marcoule Atalante facility is reviewed. A particular attention is also given to the research conducted on uranium-americium mixed-oxides fuels, which are now considered the reference fuels for MA transmutation in France.

  10. Study on Equilibrium Characteristics of Thorium-Plutonium-Minor Actinides Mixed Oxides Fuel in PWR

    NASA Astrophysics Data System (ADS)

    Waris, A.; Permana, S.; Kurniadi, R.; Su'ud, Z.; Sekimoto, H.

    2010-06-01

    A study on characteristics of thorium-plutonium-minor actinides utilization in the pressurized water reactor (PWR) with the equilibrium burnup model has been conducted. For a comprehensive evaluation, several fuel cycles scenario have been included in the present study with the variation of moderator-to-fuel volume ratio (MFR) of PWR core design. The results obviously exhibit that the neutron spectra grow to be harder with decreasing of the MFR. Moreover, the neutron spectra also turn into harder with the rising number of confined heavy nuclides. The required 233U concentration for criticality of reactor augments with the increasing of MFR for all heavy nuclides confinement and thorium & uranium confinement in PWR.

  11. FEASIBILITY OF RECYCLING PLUTONIUM AND MINOR ACTINIDES IN LIGHT WATER REACTORS USING HYDRIDE FUEL

    SciTech Connect

    Greenspan, Ehud; Todreas, Neil; Taiwo, Temitope

    2009-03-10

    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 PWRs using the promising hydride fuel assembly designs identified in Part 1 versus using oxide fuel assembly designs 3) Conducting a safety analysis to assess the likelihood of licensing hydride fuel assembly designs 4) Assessing the compatibility of hydride fuel with cladding materials and water under typical PWR operating conditions Hydride fuel was found to offer promising transmutation characteristics and is recommended for further examination as a possible preferred option for recycling plutonium in PWRs.

  12. Minor Actinide Recycle in Sodium Cooled Fast Reactors Using Heterogeneous Targets

    SciTech Connect

    Samuel Bays; Pavel Medvedev; Michael Pope; Rodolfo Ferrer; Benoit Forget; Mehdi Asgari

    2009-04-01

    This paper investigates the plausible design of transmutation target assemblies for minor actinides (MA) in Sodium Fast Reactors (SFR). A heterogeneous recycling strategy is investigated, whereby after each reactor pass, un-burned MAs from the targets are blended with MAs produced by the driver fuel and additional MAs from Spent Nuclear Fuel (SNF). A design iteration methodology was adopted for customizing the core design, target assembly design and matrix composition design. The overall design was constrained against allowable peak or maximum in-core performances. While respecting these criteria, the overall design was adjusted to reduce the total number of assemblies fabricated per refueling cycle. It was found that an inert metal-hydride MA-Zr-Hx target matrix gave the highest transmutation efficiency, thus allowing for the least number of targets to be fabricated per reactor cycle.

  13. Minor Actinide Transmutation Physics for Low Conversion Ratio Sodium Fast Reactors

    SciTech Connect

    Mehdi Asgari; Samuel E. Bays; Benoit Forget; Rodolfo Ferrer

    2007-09-01

    The effects of varying the reprocessing strategy used in the closed cycle of a Sodium Fast Reactor (SNF) prototype are presented in this paper. The isotopic vector from the aqueous separation of transuranic (TRU) elements in Light Water Reactor (LWR) spent nuclear fuel (SNF) is assumed to also vary according to the reprocessing strategy of the closed fuel cycle. The decay heat, gamma energy, and neutron emission of the fuel discharge at equilibrium are found to vary depending on the separation strategy. The SFR core used in this study corresponds to a burner configuration with a conversion ratio of ~0.5 based on the Super-PRISM design. The reprocessing strategies stemming from the choice of either metal or oxide fuel for the SFR are found to have a large impact on the equilibrium discharge decay heat, gamma energy, and neutron emission. Specifically, metal fuel SFR with pyroprocessing of the discharge produces the largest amount of TRU consumption (166 kg per Effective Full Power Year or EFPY), but also the highest decay heat, gamma energy, and neutron emission. On the other hand, an oxide fuel SFR with PUREX reprocessing minimizes the decay heat and related parameters of interest to a minimum, even when compared to thermal Mixed Oxide (MOX) or Inert Matrix Fuel (IMF) on a per mass basis. On an assembly basis, however, the metal SFR discharge has a lower decay heat than an equivalent oxide SFR assembly for similar minor actinide consumptions (~160 kg/EFPY.) Another disadvantage in the oxide PUREX reprocessing scenario is that there is no consumption of americium and curium, since PUREX reprocessing separates these minor actinides (MA) and requires them to be disposed of externally.

  14. Conceptual design of minor actinides burner with an accelerator-driven subcritical system.

    SciTech Connect

    Cao, Y.; Gohar, Y.

    2011-11-04

    In the environmental impact study of the Yucca Mountain nuclear waste repository, the limit of spent nuclear fuel (SNF) for disposal is assessed at 70,000 metric tons of heavy metal (MTHM), among which 63,000 MTHM are the projected SNF discharge from U.S. commercial nuclear power plants though 2011. Within the 70,000 MTHM of SNF in storage, approximately 115 tons would be minor actinides (MAs) and 585 tons would be plutonium. This study describes the conceptual design of an accelerator-driven subcritical (ADS) system intended to utilize (burn) the 115 tons of MAs. The ADS system consists of a subcritical fission blanket where the MAs fuel will be burned, a spallation neutron source to drive the fission blanket, and a radiation shield to reduce the radiation dose to an acceptable level. The spallation neutrons are generated from the interaction of a 1 GeV proton beam with a lead-bismuth eutectic (LBE) or liquid lead target. In this concept, the fission blanket consists of a liquid mobile fuel and the fuel carrier can be LBE, liquid lead, or molten salt. The actinide fuel materials are dissolved, mixed, or suspended in the liquid fuel carrier. Therefore, fresh fuel can be fed into the fission blanket to adjust its reactivity and to control system power during operation. Monte Carlo analyses were performed to determine the overall parameters of an ADS system utilizing LBE as an example. Steady-state Monte Carlo simulations were studied for three fission blanket configurations that are similar except that the loaded amount of actinide fuel in the LBE is either 5, 7, or 10% of the total volume of the blanket, respectively. The neutron multiplication factor values of the three configurations are all approximately 0.98 and the MA initial inventories are each approximately 10 tons. Monte Carlo burnup simulations using the MCB5 code were performed to analyze the performance of the three conceptual ADS systems. Preliminary burnup analysis shows that all three conceptual ADS

  15. The optimization of an AP1000 fuel assembly for the transmutation of plutonium and minor actinides

    NASA Astrophysics Data System (ADS)

    Washington, Jeremy A.

    The average nuclear power plant produces twenty metric tons of used nuclear fuel per year, containing approximately 95 wt% uranium, 1 wt% plutonium, and 4 wt% fission products and transuranic elements. Fast reactors are a preferred option for the transmutation of plutonium and minor actinides; however, an optimistic deployment time of at least 20 years indicates a need for a near-term solution. The goal of this thesis is to examine the potential of light water reactors for plutonium and minor actinides transmutation as a near-term solution. This thesis screens the available nuclear isotope database to identify potential absorbers as coatings on a transmutation fuel in a light water reactor. A spectral shift absorber coating tunes the neutron energy spectrum experienced by the underlying target fuel. Eleven different spectral shift absorbers (B4C, CdO, Dy2O3, Er 2O3, Eu2O3, Gd2O3, HfO2, In2O3, Lu2O3, Sm2O3, and TaC) have been selected for further evaluation. A model developed using the NEWT module of SCALE 6.1 code provided performance data for the burnup of the target fuel rods. Irradiation of the target fuels occurs in a Westinghouse 17x17 XL Robust Fuel Assembly over a 1400 Effective Full Power Days (EFPD) interval. The fuels evaluated in this thesis include PuO2, Pu3Si2, PuN, MOX, PuZrH, PuZrHTh, PuZrO 2, and PuUZrH. MOX (5 wt% PuO2), Pu0.31ZrH 1.6Th1.08, and PuZrO2MgO (8 wt%) are selected for detailed analysis in a multi-pin transmutation assembly. A coupled model optimized the resulting transmutation fuel elements. The optimization considered three stages of fuel assemblies containing target fuel pins. The first stage optimized four target fuel pins adjacent to the central instrumentation channel. The second stage evaluated a variety of assemblies with multiple target fuel pins and the third stage re-optimized target fuel pins in the second-stage assembly. A PuZrO2MgO (8 wt%) target fuel with a coating of Lu 2O3 resulted in the greatest reduction in curium-244

  16. AECL/US INERI - Development of Inert Matrix Fuels for Plutonium and Minor Actinide Management in Power Reactors -- Fuel Requirements and Down-Select Report

    SciTech Connect

    William Carmack; Randy D. Lee; Pavel Medvedev; Mitch Meyer; Michael Todosow; Holly B. Hamilton; Juan Nino; Simon Philpot; James Tulenko

    2005-06-01

    potential advantage for more efficient destruction of plutonium and minor actinides (MA) relative to MOX fuel. Greater efficiency in plutonium reduction results in greater flexibility in managing plutonium inventories and in developing strategies for disposition of MA, as well as a potential for fuel cycle cost savings. Because fabrication of plutonium-bearing (and MA-bearing) fuel is expensive relative to UO{sub 2} in terms of both capital and production, cost benefit can be realized through a reduction in the number of plutonium-bearing elements required for a given burn rate. In addition, the choice of matrix material may be manipulated either to facilitate fuel recycling or to make plutonium recovery extremely difficult. In addition to plutonium/actinide management, an inert matrix fuel having high thermal conductivity may have operational and safety benefits; lower fuel temperatures could be used to increase operating and safety margins, uprate reactor power, or a combination of both. The CANDU reactor offers flexibility in plutonium management and MA burning by virtue of online refueling, a simple bundle design, and good neutron economy. A full core of inert matrix fuel containing either plutonium or a plutonium-actinide mix can be utilized, with plutonium destruction efficiencies greater than 90%, and high (>60%) actinide destruction efficiencies. The Advanced CANDU Reactor (ACR) could allow additional possibilities in the design of an IMF bundle, since the tighter lattice pitch and light-water coolant reduce or eliminate the need to suppress coolant void reactivity, allowing the center region of the bundle to include additional fissile material and to improve actinide burning. The ACR would provide flexibility for management of plutonium and MA from the existing LWR fleet, and would be complementary to the AFCI program in the U.S. Many of the fundamental principles concerning the use of IMF are nearly identical in LWRs and the ACR, including fuel

  17. Analysis on fuel breeding capability of FBR core region based on minor actinide recycling doping

    NASA Astrophysics Data System (ADS)

    Permana, Sidik; Novitrian, Waris, Abdul; Ismail, Suzuki, Mitsutoshi; Saito, Masaki

    2014-09-01

    Nuclear fuel breeding based on the capability of fuel conversion capability can be achieved by convertion rasio of some fertile materials into fissile materials during nuclear reaction processes such as main fissile materials of U-233, U-235, Pu-239 and Pu-241 and for fertile materials of Th-232, U-238, and Pu-240 as well as Pu-238. Minor actinide (MA) loading option which consists of neptunium, americium and curium will gives some additional contribution from converted MA into plutonium such as conversion Np-237 into Pu-238 and it's produced Pu-238 converts to Pu-239 via neutron capture. Increasing composition of Pu-238 can be used to produce fissile material of Pu-239 as additional contribution. Trans-uranium (TRU) fuel (Mixed fuel loading of MOX (U-Pu) and MA composition) and mixed oxide (MOX) fuel compositions are analyzed for comparative analysis in order to show the effect of MA to the plutonium productions in core in term of reactor criticality condition and fuel breeding capability. In the present study, neptunium (Np) nuclide is used as a representative of MAin trans-uranium (TRU) fuel composition as Np-MOX fuel type. It was loaded into the core region gives significant contribution to reduce the excess reactivity in comparing to mixed oxide (MOX) fuel and in the same time it contributes to increase nuclear fuel breeding capability of the reactor. Neptunium fuel loding scheme in FBR core region gives significant production of Pu-238 as fertile material to absorp neutrons for reducing excess reactivity and additional contribution for fuel breeding.

  18. Analysis on fuel breeding capability of FBR core region based on minor actinide recycling doping

    SciTech Connect

    Permana, Sidik; Novitrian,; Waris, Abdul; Ismail; Suzuki, Mitsutoshi; Saito, Masaki

    2014-09-30

    Nuclear fuel breeding based on the capability of fuel conversion capability can be achieved by conversion ratio of some fertile materials into fissile materials during nuclear reaction processes such as main fissile materials of U-233, U-235, Pu-239 and Pu-241 and for fertile materials of Th-232, U-238, and Pu-240 as well as Pu-238. Minor actinide (MA) loading option which consists of neptunium, americium and curium will gives some additional contribution from converted MA into plutonium such as conversion Np-237 into Pu-238 and it's produced Pu-238 converts to Pu-239 via neutron capture. Increasing composition of Pu-238 can be used to produce fissile material of Pu-239 as additional contribution. Trans-uranium (TRU) fuel (Mixed fuel loading of MOX (U-Pu) and MA composition) and mixed oxide (MOX) fuel compositions are analyzed for comparative analysis in order to show the effect of MA to the plutonium productions in core in term of reactor criticality condition and fuel breeding capability. In the present study, neptunium (Np) nuclide is used as a representative of MAin trans-uranium (TRU) fuel composition as Np-MOX fuel type. It was loaded into the core region gives significant contribution to reduce the excess reactivity in comparing to mixed oxide (MOX) fuel and in the same time it contributes to increase nuclear fuel breeding capability of the reactor. Neptunium fuel loading scheme in FBR core region gives significant production of Pu-238 as fertile material to absorp neutrons for reducing excess reactivity and additional contribution for fuel breeding.

  19. Use of Thorium for Transmutation of Plutonium and Minor Actinides in PWRs

    SciTech Connect

    Shwageraus, Eugene; Hejzlar, Pavel; Kazimi, Mujid S.

    2004-07-15

    An assessment is made of the potential for Th-based fuel to minimize Pu and minor actinide (MA) production in pressurized water reactors (PWRs). Destruction rates and residual amounts of Pu and MA in the fuel used for transmutation are examined. In particular, sensitivity of these two parameters to the fuel lattice hydrogen to heavy metal (H/HM) ratio and to the fuel composition was systematically investigated. All burnup calculations were performed using CASMO4, the fuel assembly burnup code. The results indicate that up to 1000 kg of reactor-grade Pu can be burned in Th-based fuel assemblies per gigawatt (electric) year. Up to 75% of initial Pu can be destroyed per passage through reactor core. Addition of MA to the fuel mixture degrades the burning efficiency. The theoretically achievable limit for total transuranium (TRU) destruction per passage through the core is 50%. Efficient MA and Pu destruction in Th-based fuel generally requires a higher degree of neutron moderation and, therefore, higher fuel lattice H/HM ratio than typically used in the current generation of PWRs. Reactivity coefficients evaluation demonstrated the feasibility of designing a Th-Pu-MA fueled core with negative Doppler and moderator temperature coefficients. Introduction of TRU-containing fuels to a PWR core inevitably leads to lower control material worths and smaller delayed-neutron yields than with conventional UO{sub 2} cores. Therefore, a major challenge associated with the introduction of Th-TRU fuels to PWRs will be the design of the whole core and reactor control features to ensure safe reactor operation.

  20. Heterogeneous sodium fast reactor designed for transmuting minor actinide waste isotopes into plutonium fuel

    NASA Astrophysics Data System (ADS)

    Bays, Samuel Eugene

    2008-10-01

    In the past several years there has been a renewed interest in sodium fast reactor (SFR) technology for the purpose of destroying transuranic waste (TRU) produced by light water reactors (LWR). The utility of SFRs as waste burners is due to the fact that higher neutron energies allow all of the actinides, including the minor actinides (MA), to contribute to fission. It is well understood that many of the design issues of LWR spent nuclear fuel (SNF) disposal in a geologic repository are linked to MAs. Because the probability of fission for essentially all the "non-fissile" MAs is nearly zero at low neutron energies, these isotopes act as a neutron capture sink in most thermal reactor systems. Furthermore, because most of the isotopes produced by these capture reactions are also non-fissile, they too are neutron sinks in most thermal reactor systems. Conversely, with high neutron energies, the MAs can produce neutrons by fast fission. Additionally, capture reactions transmute the MAs into mostly plutonium isotopes, which can fission more readily at any energy. The transmutation of non-fissile into fissile atoms is the premise of the plutonium breeder reactor. In a breeder reactor, not only does the non-fissile "fertile" U-238 atom contribute fast fission neutrons, but also transmutes into fissile Pu-239. The fissile value of the plutonium produced by MA transmutation can only be realized in fast neutron spectra. This is due to the fact that the predominate isotope produced by MA transmutation, Pu-238, is itself not fissile. However, the Pu-238 fission cross section is significantly larger than the original transmutation parent, predominately: Np-237 and Am-241, in the fast energy range. Also, Pu-238's fission cross section and fission-to-capture ratio is almost as high as that of fissile Pu-239 in the fast neutron spectrum. It is also important to note that a neutron absorption in Pu-238, that does not cause fission, will instead produce fissile Pu-239. Given this

  1. Recovery of minor actinides from spent fuel using TPEN-immobilized gels

    SciTech Connect

    Koyama, S.; Suto, M.; Ohbayashi, H.; Oaki, H.; Takeshita, K.

    2013-07-01

    A series of separation experiments was performed in order to study the recovery process for minor actinides (MAs), such as americium (Am) and curium (Cm), from the actual spent fuel by using an extraction chromatographic technique. N,N,N',N'-tetrakis-(4-propenyloxy-2-pyridylmethyl) ethylenediamine (TPPEN) is an N,N,N',N'-tetrakis (2-pyridylmethyl) ethylenediamine (TPEN) analogue consisting of an incorporated pyridine ring that acts as not only a ligand but also as a site for polymerization and crosslinking of the gel. The TPPEN and N-isopropylacrylamide (NIPA) were dissolved into dimethylformamide (DMF, Wako Co., Ltd.) and a silica beads polymer, and then TTPEN was immobilized chemically in a polymer gel (so called TPEN-gel). Mixed oxide (MOX) fuel, which was highly irradiated up to 119 GWD/MTM in the experimental fast reactor Joyo, was used as a reference spent fuel. First, uranium (U) and plutonium (Pu) were separated from the irradiated fuel using an ion-exchange method, and then, the platinum group elements were removed by CMPO to leave a mixed solution of MAs and lanthanides. The 3 mol% TPPEN-gel was packed with as an extraction column (CV: 1 ml) and then rinsed by 0.1 M NaNO{sub 3}(pH 4.0) for pH adjustment. After washing the column by 0.01 M NaNO{sub 3} (pH 4.0), Eu was detected and the recovery rate reached 93%. The MAs were then recovered by changing the eluent to 0.01 M NaNO{sub 3} (pH 2.0), and the recovery rate of Am was 48 %. The 10 mol% TPPEN-gel was used to improve adsorption coefficient of Am and a condition of eluent temperature was changed in order to confirm the temperature swing effect on TPEN-gel for MA. More than 90% Eu was detected in the eluent after washing with 0.01 M NaNO{sub 3} (pH 3.5) at 5 Celsius degrees. Americium was backwardly detected and eluted continuously during the same condition. After removal of Eu, the eluent temperature was changed to 32 Celsius degrees, then Am was detected (pH 3.0). Finally remained Am could be stripped

  2. Thermal analysis for fuel handling system for sodium cooled reactor considering minor actinide-bearing metal fuel.

    SciTech Connect

    Chikazawa, Y.; Grandy, C.; Nuclear Engineering Division

    2009-03-01

    The Advanced Burner Reactor (ABR) is one of the components of the Global Nuclear Energy Partnership (GNEP) used to close the fuel cycle. ABR is a sodium-cooled fast reactor that is used to consume transuranic elements resulting from the reprocessing of light water reactor spent nuclear fuel. ABR-1000 [1000 MW(thermal)] is a fast reactor concept created at Argonne National Laboratory to be used as a reference concept for various future trade-offs. ABR-1000 meets the GNEP goals although it uses what is considered base sodium fast reactor technology for its systems and components. One of the considerations of any fast reactor plant concept is the ability to perform fuel-handling operations with new and spent fast reactor fuel. The transmutation fuel proposed as the ABR fuel has a very little experience base, and thus, this paper investigates a fuel-handling concept and potential issues of handling fast reactor fuel containing minor actinides. In this study, two thermal analyses supporting a conceptual design study on the ABR-1000 fuel-handling system were carried out. One analysis investigated passive dry spent fuel storage, and the other analysis investigated a fresh fuel shipping cask. Passive dry storage can be made suitable for the ABR-1000 spent fuel storage with sodium-bonded metal fuel. The thermal analysis shows that spent fast reactor fuel with a decay heat of 2 kW or less can be stored passively in a helium atmosphere. The 2-kW value seems to be a reasonable and practical level, and a combination of reasonably-sized in-sodium storage followed by passive dry storage could be a candidate for spent fuel storage for the next-generation sodium-cooled reactor with sodium-bonded metal fuel. Requirements for the shipping casks for minor actinide-bearing fuel with a high decay heat level are also discussed in this paper. The shipping cask for fresh sodium-cooled-reactor fuel should be a dry type to reduce the reaction between residual moisture on fresh fuel and the

  3. Evaluation of Homogeneous Options: Effects of Minor Actinide Exclusion from Single and Double Tier Recycle in Sodium Fast Reactors

    SciTech Connect

    R. M. Ferrer; S. Bays; M. Pope

    2008-03-01

    The Systems Analysis Campaign under the Global Nuclear Energy Partnership (GNEP) has requested the fuel cycle analysis group at the Idaho National Laboratory (INL) to analyze and provide isotopic data for four scenarios in which different strategies for Minor Actinides (MA) management are investigated. A 1000 MWth commercial-scale Sodium Fast Reactor (SFR) design was selected as the baseline in this scenario study. Two transuranic (TRU) conversion ratios, defined as the ratio of the amount of TRU produced over the TRU destroyed in the reactor core, along with different fuel-types were investigated.

  4. Sigma Team for Minor Actinide Separation: PNNL FY 2010 Status Report

    SciTech Connect

    Lumetta, Gregg J.; Sinkov, Sergey I.; Neiner, Doinita; Levitskaia, Tatiana G.; Braley, Jenifer C.; Carter, Jennifer C.; Warner, Marvin G.; Pittman, Jonathan W.; Rapko, Brian M.

    2010-08-24

    Work conducted at Pacific Northwest National Laboratory (PNNL) in FY 2010 addressed two lines of inquiry. The two hypotheses put forth were: 1. The extractants from the TRUEX( ) process (CMPO)( ) and from the TALSPEAK( ) process (HDEHP)( ) can be combined into a single process solvent to separate 1) the lanthanides and actinides from acidic high-level waste and 2) the actinides from the lanthanides in a single solvent extraction process. (Note: This combined process will hereafter be referred to as the TRUSPEAK process.) A series of empirical measurements performed (both at PNNL and Argonne National Laboratory) in FY 2009 supported this hypothesis, but also indicated some nuances to the chemistry. Lanthanide/americium separation factors of 12 and higher were obtained with a prototypic TRUSPEAK solvent when extracting the lanthanides from a citrate-buffered DTPA( ) solution. Although the observed separation factors are sufficiently high to design an actinide/lanthanide separation process, a better understanding of the chemistry is expected to lead to improved solvent formulations and improved process performance. Work in FY 2010 focused on understanding the synergistic extraction behavior observed for Nd(III) and Am(III) when extracted into mixtures of CMPO and HDEHP. The interaction between CMPO and HDEHP in dodecane was investigated by 31P NMR spectroscopy, and an adduct of the type CMPO•HDEHP was found to form. The formation of this adduct will reduce the effective extractant concentrations and must be taken into account when modeling metal ion extraction data in this system. Studies were also initiated to determine the Pitzer parameters for Nd(III) in lactate media. 2. Higher oxidation states (e.g., +5 and +6) of Am can be stabilized in solution by complexation with uranophilic ligands, and this chemistry can be exploited to separate Am from Cm. To test this hypothesis, the previously reported stereognostic uranophilic ligands NPB( ) and ETAC(e) were

  5. Fission cross-section measurements on 233U and minor actinides at the CERN n_TOF facility

    NASA Astrophysics Data System (ADS)

    Calviani, M.; Colonna, N.; Abbondanno, U.; Aerts, G.; Álvarez, H.; Álvarez-Velarde, F.; Andriamonje, S.; Andrzejewski, J.; Assimakopoulos, P.; Audouin, L.; Badurek, G.; Baumann, P.; Bečvář, F.; Belloni, F.; Berthoumieux, E.; Calviño, F.; Cano-Ott, D.; Capote, R.; Carrapiço, C.; Cennini, P.; Chepel, V.; Chiaveri, E.; Cortes, G.; Couture, A.; Cox, J.; Dahlfors, M.; David, S.; Dillmann, I.; Domingo-Pardo, C.; Dridi, W.; Duran, I.; Eleftheriadis, C.; Embid-Sesura, M.; Ferrant, L.; Ferrari, A.; Ferreira-Marques, R.; Fujii, K.; Furman, W.; Goncalves, I.; González-Romero, E.; Goverdovski, A.; Gramegna, F.; Guerrero, C.; Gunsing, F.; Haas, B.; Haight, R.; Heil, M.; Herrera-Martinez, A.; Igashira, M.; Jericha, E.; Käppeler, F.; Kadi, Y.; Karadimos, D.; Karamanis, D.; Ketlerov, V.; Kerveno, M.; Koehler, P.; Konovalov, V.; Kossionides, E.; Krtička, M.; Lampoudis, C.; Leeb, H.; Lindote, A.; Lopes, I.; Lozano, M.; Lukic, S.; Marganiec, J.; Marrone, S.; Martínez, T.; Massimi, C.; Mastinu, P.; Mengoni, A.; Milazzo, P. M.; Moreau, C.; Mosconi, M.; Neves, F.; Oberhummer, H.; O'Brien, S.; Pancin, J.; Papachristodoulou, C.; Papadopoulos, C.; Paradela, C.; Patronis, N.; Pavlik, A.; Pavlopoulos, P.; Perrot, L.; Pigni, M. T.; Plag, R.; Plompen, A.; Plukis, A.; Poch, A.; Praena, J.; Pretel, C.; Quesada, J.; Rauscher, T.; Reifarth, R.; Rubbia, C.; Rudolf, G.; Rullhusen, P.; Salgado, J.; Santos, C.; Sarchiapone, L.; Savvidis, I.; Stephan, C.; Tagliente, G.; Tain, J. L.; Tassan-Got, L.; Tavora, L.; Terlizzi, R.; Vannini, G.; Vaz, P.; Ventura, A.; Villamarin, D.; Vincente, M. C.; Vlachoudis, V.; Vlastou, R.; Voss, F.; Walter, S.; Wiescher, M.; Wisshak, K.

    2009-10-01

    Neutron-induced fission cross-sections of minor actinides have been measured at the white neutron source n_TOF at CERN, Geneva. The studied isotopes include 233U, interesting for Th/U based nuclear fuel cycles, 241,243Am and 245Cm, relevant for transmutation and waste reduction studies in new generation fast reactors (Gen-IV) or Accelerator Driven Systems. The measurements take advantage of the unique features of the n_TOF facility, namely the wide energy range, the high instantaneous neutron flux and the low background. Results for the involved isotopes are reported from ~30 meV to around 1 MeV neutron enegy. The measurements have been performed with a dedicated Fission Ionization Chamber (FIC), relative to the standard cross-section of the 235U fission reaction, measured simultaneously with the same detector. Results are here reported.

  6. Evaluation of Heterogeneous Options: Effects of MgO versus UO2 Matrix Selection for Minor Actinide Targets in a Sodium Fast Reactor

    SciTech Connect

    M. Pope; S. Bays; R. Ferrer

    2008-03-01

    The primary focus of this work was to compare MgO with UO2 as target matrix material options for burning minor actinides in a transmutation target within a sodium fast reactor. This analysis compared the transmutation performance of target assemblies having UO2 matrix to those having specifically MgO inert matrix.

  7. Granulation and infiltration processes for the fabrication of minor actinide fuels, targets and conditioning matrices

    NASA Astrophysics Data System (ADS)

    Nästren, C.; Fernandez, A.; Haas, D.; Somers, J.; Walter, M.

    2007-05-01

    The impact of Pu and Am, two elements that potentially pose a long term hazard for the disposal of spent nuclear fuel, can be abated by their reintroduction into the fuel cycle for transmutation. Such transmutation targets can be fabricated by a sol gel method for the production of porous inactive beads, which are then infiltrated by Am solutions. Following calcination, compaction into pellets and sintering, the product is obtained. At its heart, the sol gel process relies on an ammonia precipitation, so that it is not universally applicable. Therefore, an alternative is sought not just to overcome this chemical limitation, but also to simplify the process and reduce waste streams. The new concept utilises powder metallurgy routes (compaction, crushing and sieving) to produce porous, almost, dust free granules, which are infiltrated with the actinide nitrate. The method has been developed using yttria stabilised zirconia and alumina, and has been demonstrated for the production of Al2O3-AmO2 targets for neutron capture investigations. The results are very promising and meet light water reactor fuel specifications. In addition, the process is ideally suited for the production of ceramic matrices for conditioning actinides for geological disposal.

  8. Comparison of Dithiophosphinic and Phosphinic Acid Derivatives for Minor Actinide Extraction

    SciTech Connect

    Mason K Harrup; Dean R. Peterman; Thomas A. Luther; Mitchell R. Greenhalgh; John R. Klaehn

    2008-03-01

    A new extractant for the separation of actinide(III) and lanthanide(III), bis(otrifluoromethylphenyl) phosphinic acid (O-PA) was synthesized. The synthetic route employed mirrors one that was employed to produce the sulfur containing analog bis(otrifluoromethylphenyl) dithiophosphinic acid (S-PA). Multinuclear NMR spectroscopy was used for elementary characterization of the new O-PA derivative. This new O-PA extractant was used to perform Am(III)/Eu(III) separations and the results were directly compared to those obtained in identical separation experiments using S-PA, an extractant that is known to exhibit separation factors of ~100,000 at low pH. The separations data are presented and discussed in terms comparing the nature of the oxygen atom as a donor to that of the sulfur atom in extractants that are otherwise identical.

  9. Comparison of Aromatic Dithiophoshinic and Phosphinic Acid Derivatives for Minor Actinide Extraction

    SciTech Connect

    John R. Klaehn; Dean R. Peterman; Mason K. Harrup; Richard D. Tillotson; Mitchell R. Greenhalgh; Thomas A. Luther; Jack D. Law; Lee M. Daniels

    2008-03-01

    A new extractant for the separation of actinide(III) and lanthanide(III), bis(otrifluoromethylphenyl) phosphinic acid (O-PA) was synthesized. The synthetic route employed mirrors one that was employed to produce the sulfur containing analog bis(otrifluoromethylphenyl) dithiophosphinic acid (S-PA). Multinuclear NMR spectroscopy was used for elementary characterization of the new O-PA derivative. This new O-PA extractant was used to perform Am(III)/Eu(III) separations and the results were directly compared to those obtained in identical separation experiments using S-PA, an extractant that is known to exhibit separation factors of ~100,000 at low pH. The separations data are presented and discussed in terms comparing the nature of the oxygen atom as a donor to that of the sulfur atom in extractants that are otherwise identical.

  10. Progress of nitride fuel cycle research for transmutation of minor actinides

    SciTech Connect

    Arai, Yasuo; Akabori, Mitsuo; Minato, Kazuo

    2007-07-01

    Recent progress of nitride fuel cycle research for transmutation of MA is summarized. Preparation of MA-bearing nitride pellets, such as (Np,Am)N, (Am,Pu)N and (Np,Pu,Am,Cm)N, was carried out. Irradiation behavior of U-free nitride fuel was investigated by the irradiation test of (Pu,Zr)N and PuN+TiN fuels, in which ZrN and TiN were added as a possible diluent material. Further, pyrochemical process of spent nitride fuel was developed by electrorefining in a molten chloride salt and subsequent re-nitridation of actinides in liquid Cd cathode electro-deposits. Nitride fuel cycle for transmutation of MA has been demonstrated in a laboratory scale by the experimental study with MA and Pu. (authors)

  11. Computational Benchmark for Estimation of Reactivity Margin from Fission Products and Minor Actinides in PWR Burnup Credit

    SciTech Connect

    Wagner, J.C.

    2001-08-02

    This report proposes and documents a computational benchmark problem for the estimation of the additional reactivity margin available in spent nuclear fuel (SNF) from fission products and minor actinides in a burnup-credit storage/transport environment, relative to SNF compositions containing only the major actinides. The benchmark problem/configuration is a generic burnup credit cask designed to hold 32 pressurized water reactor (PWR) assemblies. The purpose of this computational benchmark is to provide a reference configuration for the estimation of the additional reactivity margin, which is encouraged in the U.S. Nuclear Regulatory Commission (NRC) guidance for partial burnup credit (ISG8), and document reference estimations of the additional reactivity margin as a function of initial enrichment, burnup, and cooling time. Consequently, the geometry and material specifications are provided in sufficient detail to enable independent evaluations. Estimates of additional reactivity margin for this reference configuration may be compared to those of similar burnup-credit casks to provide an indication of the validity of design-specific estimates of fission-product margin. The reference solutions were generated with the SAS2H-depletion and CSAS25-criticality sequences of the SCALE 4.4a package. Although the SAS2H and CSAS25 sequences have been extensively validated elsewhere, the reference solutions are not directly or indirectly based on experimental results. Consequently, this computational benchmark cannot be used to satisfy the ANS 8.1 requirements for validation of calculational methods and is not intended to be used to establish biases for burnup credit analyses.

  12. Experimental Findings On Minor Actinide And Lanthanide Separations Using Ion Exchange

    SciTech Connect

    Hobbs, D. T.; Shehee, T. C.; Clearfield, A.

    2013-09-17

    This project seeks to determine if inorganic or hybrid inorganic ion-exchange materials can be exploited to provide effective americium and curium separations. Specifically, we seek to understand the fundamental structural and chemical factors responsible for the selectivity of the tested ion-exchange materials for actinide and lanthanide ions. During FY13, experimental work focused in the following areas: (1) investigating methods to oxidize americium in dilute nitric acid with subsequent ion-exchange performance measurements of ion exchangers with the oxidized americium and (2) synthesis, characterization and testing of ion-exchange materials. Ion-exchange materials tested included alkali titanates, alkali titanosilicates, carbon nanotubes and group(IV) metal phosphonates. Americium oxidation testing sought to determine the influence that other redox active components may have on the oxidation of Am(III). Experimental findings indicated that Pu(IV) is oxidized to Pu(VI) by peroxydisulfate, but there are no indications that the presence of plutonium affects the rate or extent of americium oxidation at the concentrations of peroxydisulfate being used. Tests also explored the influence of nitrite on the oxidation of Am(III). Given the formation of Am(V) and Am(VI) in the presence of nitrite, it appears that nitrite is not a strong deterrent to the oxidation of Am(III), but may be limiting Am(VI) by quickly reducing Am(VI) to Am(V). Interestingly, additional absorbance peaks were observed in the UV-Vis spectra at 524 and 544 nm in both nitric acid and perchloric acid solutions when the peroxydisulfate was added as a solution. These peaks have not been previously observed and do not correspond to the expected peak locations for oxidized americium in solution. Additional studies are in progress to identify these unknown peaks. Three titanosilicate ion exchangers were synthesized using a microwave-accelerated reaction system (MARS�) and determined to have high

  13. One-group fission cross sections for plutonium and minor actinides inserted in calculated neutron spectra of fast reactor cooled with lead-208 or lead-bismuth eutectic

    SciTech Connect

    Khorasanov, G. L.; Blokhin, A. I.

    2012-07-01

    The paper is dedicated to one-group fission cross sections of Pu and MA in LFRs spectra with the aim to increase these values by choosing a coolant which hardens neutron spectra. It is shown that replacement of coolant from Pb-Bi with Pb-208 in the fast reactor RBEC-M, designed in Russia, leads to increasing the core mean neutron energy. As concerns fuel Pu isotopes, their one-group fission cross sections become slightly changed, while more dramatically Am-241 one-group fission cross section is changed. Another situation occurs in the lateral blanket containing small quantities of minor actinides. It is shown that as a result of lateral blanket mean neutron energy hardening the one-group fission cross sections of Np-237, Am-241 and Am-243 increases up to 8-11%. This result allows reducing the time of minor actinides burning in FRs. (authors)

  14. Synthesis and structure of Ce1-xEuxPO4 solid solutions for minor actinides immobilization

    NASA Astrophysics Data System (ADS)

    Wang, Xiaohuan; Teng, Yuancheng; Huang, Yi; Wu, Lang; Zeng, Pan

    2014-08-01

    Ce1-xEuxPO4 (x = 0-1) solid solutions were synthesized by the solid state reaction process using europium (Eu) as the surrogate for trivalent minor actinide americium (Am). The effects of calcination temperature, holding time and Eu content on the crystalline phase, microstructure and morphology of Ce1-xEuxPO4 (x = 0-1) were investigated. The monazite-type EuPO4 and CePO4 coexisted after being calcined at 1000 °C for 4 h, suggesting the CePO4 and EuPO4 phases would form initially separately. Pure and single-phase monazite-type Ce1-xEuxPO4 (x = 0-1) powders were obtained at 1300 °C for 4 h. The results of the XRD patterns Rietveld refinement and μ-Raman analysis confirmed the formation of a Ce1-xEuxPO4 (x = 0-1) continuous solid solution. The grain size of Ce0.5Eu0.5PO4 increased obviously as the holding time extended. The Ce, Eu, P and O elements were almost distributed homogeneously in the Ce0.5Eu0.5PO4 solid solution.

  15. Predicting thermo-mechanical behaviour of high minor actinide content composite oxide fuel in a dedicated transmutation facility

    NASA Astrophysics Data System (ADS)

    Lemehov, S. E.; Sobolev, V. P.; Verwerft, M.

    2011-09-01

    The European Facility for Industrial Transmutation (EFIT) of the minor actinides (MA), from LWR spent fuel is being developed in the integrated project EUROTRANS within the 6th Framework Program of EURATOM. Two composite uranium-free fuel systems, containing a large fraction of MA, are proposed as the main candidates: a CERCER with magnesia matrix hosting (Pu,MA)O 2-x particles, and a CERMET with metallic molybdenum matrix. The long-term thermal and mechanical behaviour of the fuel under the expected EFIT operating conditions is one of the critical issues in the core design. To make a reliable prediction of long-term thermo-mechanical behaviour of the hottest fuel rods in the lead-cooled version of EFIT with thermal power of 400 MW, different fuel performance codes have been used. This study describes the main results of modelling the thermo-mechanical behaviour of the hottest CERCER fuel rods with the fuel performance code MACROS which indicate that the CERCER fuel residence time can safely reach at least 4-5 effective full power years.

  16. Preliminary Study on Utilization of Carbon Dioxide as a Coolant of High Temperature Engineering Test Reactor with MOX and Minor Actinides Fuel

    SciTech Connect

    Fauzia, A. F.; Waris, A.; Novitrian

    2010-06-22

    High temperature engineering test reactor (HTTR) is an uranium oxide (UO2) fuel, graphite moderator and helium gas-cooled reactor with 30 MW in thermal output and outlet coolant temperature of 950 deg. C. Instead of using helium gas, we have utilized carbon dioxide as a coolant in the present study. Beside that, uranium and plutonium oxide (mixed oxide, MOX) and minor actinides have been employed as a new fuel type of HTTR. Utilization of plutonium and minor actinide is one of the support system to non-proliferation issue in the nuclear development. The enrichment for uranium oxide has been varied of 6-20% with plutonium and minor actinides concentration of 10%. In this study, burnup period is 1100 days. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. Reactor core calculation was done by using CITATION module. The result shows that HTTR can achieve its criticality condition with 14% of {sup 235}U enrichment.

  17. Preliminary Study on Utilization of Carbon Dioxide as a Coolant of High Temperature Engineering Test Reactor with MOX and Minor Actinides Fuel

    NASA Astrophysics Data System (ADS)

    Fauzia, A. F.; Waris, A.; Novitrian

    2010-06-01

    High temperature engineering test reactor (HTTR) is an uranium oxide (UO2) fuel, graphite moderator and helium gas-cooled reactor with 30 MW in thermal output and outlet coolant temperature of 950° C. Instead of using helium gas, we have utilized carbon dioxide as a coolant in the present study. Beside that, uranium and plutonium oxide (mixed oxide, MOX) and minor actinides have been employed as a new fuel type of HTTR. Utilization of plutonium and minor actinide is one of the support system to non-proliferation issue in the nuclear development. The enrichment for uranium oxide has been varied of 6-20% with plutonium and minor actinides concentration of 10%. In this study, burnup period is 1100 days. The reactor cell calculation was performed by using SRAC 2002 code, with nuclear data library was derived from JENDL3.2. Reactor core calculation was done by using CITATION module. The result shows that HTTR can achieve its criticality condition with 14% of 235 U enrichment.

  18. Zirconia Inert Matrix Fuel for Plutonium and Minor Actinides Management in Reactors and as an Ultimate Waste Form

    SciTech Connect

    Degueldre, Claude; Wiesenack, Wolfgang

    2008-07-01

    An yttria stabilised zirconia doped with plutonia and erbia has been selected as inert matrix fuel (IMF) at PSI. The results of experimental irradiation tests on yttria-stabilised zirconia doped with plutonia and erbia pellets in the Halden research reactor as well as a study of zirconia solubility are presented. Zirconia must be stabilised by yttria to form a solid solution such as MAz(Y,Er){sub y}Pu{sub x}Zr{sub 1-y}O{sub 2-{xi}} where minor actinides (MA) oxides are also soluble. (Er,Y,Pu,Zr)O{sub 2-{xi}} (with Pu containing 5% Am) was successfully prepared at PSI and irradiated in the Halden reactor. Emphasis is given on the zirconia- IMF properties under in-pile irradiation, on the fuel material centre temperatures and on the fission gas release. The retention of fission products in zirconia may be stronger at similar temperature, compared to UO{sub 2}. The outstanding behaviour of plutonia-zirconia inert matrix fuel is compared to the classical (U,Pu)O{sub 2} fuels. The properties of the spent fuel pellets are presented focusing on the once-through strategy. For this strategy, low solubility of the inert matrix is required for geological disposal. This parameter was studied in detail for a range of solutions corresponding to groundwater under near field conditions. Under these conditions the IMF solubility is about 109 times smaller than glass, several orders of magnitude lower than UO{sub 2} in oxidising conditions (Yucca Mountain) and comparable in reducing conditions, which makes the zirconia material very attractive for deep geological disposal. The behaviour of plutonia-zirconia inert matrix fuel is discussed within a 'burn and bury' strategy. (authors)

  19. Increasing the Acceptance of Spent Nuclear Fuel Disposal by the Transmutation of Minor Actinides Using an Accelerator

    NASA Astrophysics Data System (ADS)

    Sheffield, Richard L.

    2010-02-01

    The main challenge in nuclear fuel cycle closure is the reduction of the potential radiotoxicity of spent LWR nuclear fuel, or the length of time in which that potential hazard exists. Partitioning and accelerator-based transmutation in combination with geological disposal can lead to an acceptable societal solution for the nuclear spent fuel management problem. Nuclear fuel seems ideally suited for recycling. Only a small fraction of the available energy in the fuel is extracted in a single pass and the problem isotopes, consisting of the transuranic elements plutonium, neptunium, americium, curium and the long-lived fission products iodine and technetium, could be burned in fast-neutron spectrum reactors or sub-critical accelerator driven transmuters. Most of the remaining wastes have half-lives of a few hundred years and can be safely stored in man-made containment structures (casks or glass). The very small amount of remaining long-lived waste could be safely stored in a small geologic repository. The problem for the next 100 years is that a sufficient number of fast reactors are unlikely to be built by industry to burn its own waste and the waste from existing and new light water reactors (LWRs). So an interim solution is required to transition to a fast reactor economy. The goals of accelerator transmutation are some or all of the following: 1) to significantly reduce the impacts due to the minor actinides on the packing density and long-term radiotoxicity in the repository design, 2) preserve/use the energy-rich component of used nuclear fuel, and 3) reduce proliferation risk. Accelerator-based transmutation could lead to a greater percentage of our power coming from greenhouse-gas emission-free nuclear power and provide a long-term strategy enabling the continuation and growth of nuclear power in the U.S. )

  20. Selective recovery of minor trivalent actinides from high level liquid waste by R-BTP/SiO2-P adsorbents

    NASA Astrophysics Data System (ADS)

    Sano, Yuichi; Surugaya, Naoki; Yamamoto, Masahiko

    2010-03-01

    Concerning the selective recovery of minor trivalent actinides (MA(III) = Am(III) and Cm(III)) from high level liquid waste (HLLW) by extraction chromatography, adsorption and elution behaviours of MA(III) and fission products (FP) in a nitric acid media were studied using iHex-BTP/SiO2-P adsorbents, which is expected to show high adsorption affinity for MA(III) even in concentrated HNO3 solution, such as HLLW. In the batch experiments, Pd showed strong adsorption on iHex-BTP/SiO2-P adsorbents under any concentration of HNO3. The MA(III) and heavy Ln(III) (Sm(III), Eu(III) and Gd(III)) were also adsorbed at the condition of high HNO3 concentration, but they showed no adsorption under low HNO3concentration. The separation factor for MA(III)/heavy Ln(III) took the maximum value (over 100) at around 1mol/dm3 HNO3. It was difficult to elute MA(III) or heavy Ln(III) selectively by HNO3 from the iHex-BTP/SiO2-P adsorbents degradated by γ-ray irradiation. The chromatographic separation of real HLLW by an iHex-BTP/SiO2-P column showed that MA(III) could be recovered selectively by adjusting the acidity of the feed solution, i.e. HLLW, to 1mol/dm3 and using H2O as eluant. The adsorption of Pd(II) can be decreased by the addition of appropriate complexing reagents, e.g. DTPA, into HLLW without any effects on the MA(III) adsorption.

  1. The Itemized NIHSS Scores Are Associated With Discharge Disposition in Patients With Minor Stroke

    PubMed Central

    Andrews, Howard; Boehme, Amelia K.; Marshall, Randolph S.; Boden-Albala, Bernadette

    2016-01-01

    Background and purpose: The ability of the National Institutes of Health Stroke Scale (NIHSS) score to predict functional outcome in minor stroke is controversial. In this study, we examined the association of itemized NIHSS score with discharge outcome. Methods: We included all patients with final diagnosis of stroke with an NIHSS score of 0 to 5 untreated with thrombolysis enrolled in the “Stroke Warning Information and Faster Treatment” trial. Individual components of the NIHSS score were the primary predictors. Poor outcome was defined as not being discharged home. Logistic regression was used to identify predictors of outcome. Results: A total of 861 patients met the inclusion criteria; 162 (19%) were not discharged home. In multivariable regression, predictors of discharge other than home were age (odds ratio [OR] = 1.02 per year increase, P < .001) and total NIHSS score (OR per unit increase in the NIHSS = 1.51, P < .001). Motor (OR = 2.32, P < .001), level of consciousness (LOC; OR = 6.62, P = .004), and ataxia (OR = 3.10, P < .001) were also associated with not being discharged home. Motor (area under the curve [AUC] 0.623) appeared to be more predictive of poor outcome than ataxia (AUC 0.569) and LOC (AUC 0.517). The total NIHSS had a fair correlation with discharge outcome (AUC 0.683). Conclusion: Total and itemized NIHSS components have a fair correlation with outcome in minor stroke highlighting the importance of other measures of stroke severity for clinical trials. PMID:27366292

  2. Study of solid extractants based on malonamides, diglycolamides, and bipyridines for the partitioning of minor actinides from high active wastes

    NASA Astrophysics Data System (ADS)

    Šul'Aková, J.; John, J.; Šebesta, F.

    2006-01-01

    In this work, the performance of the solid extractants with polyacrylonitrile (PAN) binding matrix was studied for the separation of lanthanides and actinides from nitric acid solutions. As extractants, incorporated into the PAN matrix, the N,N‧-dimethyl-N,N‧-dibutyltetradecylmalonamide (DMDBTDMA), N,N‧-dimethyl-N,N‧-dioctyl-hexy-loxyethylmalonamide (DMDOHEMA), N,N,N‧,N‧-tetraoctyldiglycolamide (TODGA), 6,6‧-bis-(5,6-dipentyl-[1,2,4]triazin-3-yl[2,2‧]bipyridinyl (C5BTBP) were used. Weight distribution coefficients Dg of europium and several actinides have been determined for all the composite materials. The kinetics of europium uptake, practical dynamic extraction capacities, and extraction isotherms were also determined. The results obtained revealed that the solid extractants studied are prospective for the partitioning of lanthanides and actinides from liquid radioactive wastes.

  3. Synthesis and crystalline phase of monazite-type Ce1-xGdxPO4 solid solutions for immobilization of minor actinide curium

    NASA Astrophysics Data System (ADS)

    Yang, Hang; Teng, Yuancheng; Ren, Xuetan; Wu, Lang; Liu, Haichang; Wang, Shanlin; Xu, Liuyang

    2014-01-01

    Gadolinium (Gd3+) was used to simulate trivalent minor actinide curium (Cm3+), and monazite-type solid solutions with composition of Ce1-xGdxPO4 (x = 0-1) were prepared by the solid state reaction method using Ce2(C2O4)3·10H2O, NH4H2PO4, and Gd2O3 as starting materials. The effects of Gd content on the crystalline phase and microstructure of Ce1-xGdxPO4 solid solutions were investigated, and the calcining parameters of Ce0.9Gd0.1PO4 solid solution were optimized by means of XRD, TG-DSC and SEM. The results show that pure monazite-type crystalline phase was obtained for the Ce1-xGdxPO4 with x = 0-1, and the incorporation of minor actinide curium simulated by gadolinium in monazite was confirmed. The change of Gd content had no significant effect on the microstructure of Ce1-xGdxPO4 solid solutions, and the grain size was approximately 0.1-1 μm. Besides, the optimal calcining temperature and holding time of Ce0.9Gd0.1PO4 solid solution were 1000 °C and 2 h, respectively.

  4. Bias estimates used in lieu of validation of fission products and minor actinides in MCNP Keff calculations for PWR burnup credit casks

    SciTech Connect

    Mueller, Don E.; Marshall, William J.; Wagner, John C.; Bowen, Douglas G.

    2015-09-01

    The U.S. Nuclear Regulatory Commission (NRC) Division of Spent Fuel Storage and Transportation recently issued Interim Staff Guidance (ISG) 8, Revision 3. This ISG provides guidance for burnup credit (BUC) analyses supporting transport and storage of PWR pressurized water reactor (PWR) fuel in casks. Revision 3 includes guidance for addressing validation of criticality (keff) calculations crediting the presence of a limited set of fission products and minor actinides (FP&MA). Based on previous work documented in NUREG/CR-7109, recommendation 4 of ISG-8, Rev. 3, includes a recommendation to use 1.5 or 3% of the FP&MA worth to conservatively cover the bias due to the specified FP&MAs. This bias is supplementary to the bias and bias uncertainty resulting from validation of keff calculations for the major actinides in SNF and does not address extension to actinides and fission products beyond those identified herein. The work described in this report involves comparison of FP&MA worths calculated using SCALE and MCNP with ENDF/B-V, -VI, and -VII based nuclear data and supports use of the 1.5% FP&MA worth bias when either SCALE or MCNP codes are used for criticality calculations, provided the other conditions of the recommendation 4 are met. The method used in this report may also be applied to demonstrate the applicability of the 1.5% FP&MA worth bias to other codes using ENDF/B V, VI or VII based nuclear data. The method involves use of the applicant s computational method to generate FP&MA worths for a reference SNF cask model using specified spent fuel compositions. The applicant s FP&MA worths are then compared to reference values provided in this report. The applicants FP&MA worths should not exceed the reference results by more than 1.5% of the reference FP&MA worths.

  5. 25 CFR 11.1011 - Dispositional hearing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... ORDER CODE Juvenile Offender Procedure § 11.1011 Dispositional hearing. (a) A dispositional hearing... prepared by the minor and his or her attorney, if any. (e) The dispositional order constitutes a...

  6. Gadolinium speciation with Tetradentate, N-donor extractants for minor actinide/lanthanide separation: an XRD, mass spectrometry and EPR study

    SciTech Connect

    Whittaker, D.M.; Sharrad, C.A.; Sproules, S.

    2013-07-01

    The hydrophobic organic molecules CyMe{sub 4}-BTPhen (1) and CyMe{sub 4}-BTBP (2) have been developed and tuned over many years to be able to separate the trivalent actinides from the trivalent lanthanides (Ln) selectively in bi-phasic solvent extraction processes for the separation of the long-lived radio-toxic minor actinides from spent nuclear fuel. The ability of these N-donor ligands to perform this separation is poorly understood, as is their speciation with the metal ions when extracted into the organic phase. Our previous work has shown Ln{sup 3+} speciation to be largely 1:2 Ln:L in nature with another small molecule, either water or nitrate, occupying a cavity between the tetradentate bound N-donor ligands. The identity of the small molecule changes across the lanthanide series, and here we continue investigations into this speciation. Complexes of these N-donor ligands with Gd{sup 3+} have been synthesised and characterised by X-ray crystallography, mass spectrometry and EPR spectroscopy. We show that the N-donor ligands have no effect on the electronic configuration of Gd{sup 3+} and that the lanthanide contraction with the steric rigidity of the N-donor ligand appears to determine the size of the cavity between the coordinated ligands. This in turn appears to control the identity of the small molecule on the ninth site in the 1:2 Gd:L species. (authors)

  7. Atomistic Calculations of the Effect of Minor Actinides on Thermodynamic and Kinetic Properties of UO{sub 2{+-}x}

    SciTech Connect

    Deo, Chaitanya; Adnersson, Davis; Battaile, Corbett; uberuaga, Blas

    2012-10-30

    The team will examine how the incorporation of actinide species important for mixed oxide (MOX) and other advanced fuel designs impacts thermodynamic quantities of the host UO{sub 2} nuclear fuel and how Pu, Np, Cm and Am influence oxygen mobility. In many cases, the experimental data is either insufficient or missing. For example, in the case of pure NpO2, there is essentially no experimental data on the hyperstoichiometric form it is not even known if hyperstoichiometry NpO{sub 2{+-}x} is stable. The team will employ atomistic modeling tools to calculate these quantities

  8. Basic Characteristics of Bis(2-ethylhexyl)phosphate-impregnated Adsorbent Used for Separation of Minor Actinides from FBR-Spent Fuel

    NASA Astrophysics Data System (ADS)

    Oda, Ryohei; Arai, Tsuyoshi; Nagayama, Katsuhisa; Watanabe, Sou; Sano, Yuichi; Myouchin, Munetaka

    FBR-spent nuclear fuel includes a great deal of minor actinides (MA: Am and Cm), which become febrile. Radioactive wastes including MA require a large area of ground for dumping and result in high cost. In Fast Reactor Cycel System Technology Development Project (FaCT) in Japan, we have been investigating extraction chromatography for separation of long-lived MA and specific fission products (FP) from high-level liquid wastes (HLLW). This method is expected to allow us to reduce an organic solvent use and to realize compact equipment. In this work, we have studied the static and dynamic adsorption behavior of representative FP contained in HLLW, Mo(VI), Zr(IV), Nd(III) and EU(III), on a bis(2-ethylhexyl)phosphate (HDEHP)-impregnated adsorbent. Such fundamental data should facilitate the efficient design of efficient MA recovery processes. Column adsorption experiments with the HDEHP-impregnated adsorbent have revealed that an increase in a flow rate results in a short breakthrough time and reduces the adsorption capacity of the column for all the elements tested. These results strongly suggest that a lower flow rate is preferable to enhance the adsorption capacity of the adsorbent.

  9. Modelling the behaviour of oxide fuels containing minor actinides with urania, thoria and zirconia matrices in an accelerator-driven system

    NASA Astrophysics Data System (ADS)

    Sobolev, V.; Lemehov, S.; Messaoudi, N.; Van Uffelen, P.; Aı̈t Abderrahim, H.

    2003-06-01

    The Belgian Nuclear Research Centre, SCK • CEN, is currently working on the pre-design of the multipurpose accelerator-driven system (ADS) MYRRHA. A demonstration of the possibility of transmutation of minor actinides and long-lived fission products with a realistic design of experimental fuel targets and prognosis of their behaviour under typical ADS conditions is an important task in the MYRRHA project. In the present article, the irradiation behaviour of three different oxide fuel mixtures, containing americium and plutonium - (Am,Pu,U)O 2- x with urania matrix, (Am,Pu,Th)O 2- x with thoria matrix and (Am,Y,Pu,Zr)O 2- x with inert zirconia matrix stabilised by yttria - were simulated with the new fuel performance code MACROS, which is under development and testing at the SCK • CEN. All the fuel rods were considered to be of the same design and sizes: annular fuel pellets, helium bounded with the stainless steel cladding, and a large gas plenum. The liquid lead-bismuth eutectic was used as coolant. Typical irradiation conditions of the hottest fuel assembly of the MYRRHA subcritical core were pre-calculated with the MCNPX code and used in the following calculations as the input data. The results of prediction of the thermo-mechanical behaviour of the designed rods with the considered fuels during three irradiation cycles of 90 EFPD are presented and discussed.

  10. The carbon matrices made of pyrolyzed phthalocyanines as a base for encapsulation of the long-lived nuclides of iodine, technetium and minor actinides

    SciTech Connect

    Tikhonov, V.I.; Moskalev, P.N.; Kapustin, V.K.

    2007-07-01

    The creation and careful investigation of suitable materials and forms for transmutation of the long-lived radioactive waste (RW) is mainly in the starting stage. A new carbon material formed as a result of pyrolysis of bis-phthalocyanine, Pc2Me, gives a chance to solve this goal successfully. The pyrolysis takes place under an argon (Ar) atmosphere at temperature of 700 - 800 deg. C. The release of atoms encapsulated inside this carbon matrix occurs only at temperatures above 1200 deg. C, and a correlation between the efficiency of the atoms' release and their atomic radius has been revealed. It is caused with creation of closed micro-cavities in the carbon skeleton during pyrolysis of MeC 2. Due to inert features and high thermostability of carbon, an inculcation of the long-lived radionuclides in these micro-cavities by means of their phthalocyanines pyrolysis gives unique opportunities for both their transmutation and storage. The first results on encapsulation within matrixes of radionuclides of europium (Eu), technetium (Te), iodine (I) and 'minor actinides' are presented. The efficiency of encapsulation is close to 100% for all studied elements excluding iodine, for the last one, it is near 85-90%. The results on thermochemical stability, leaching and other tests of these matrixes are presented. (authors)

  11. Synthesis, phase structure and microstructure of monazite-type Ce1-xPrxPO4 solid solutions for immobilization of minor actinide neptunium

    NASA Astrophysics Data System (ADS)

    Zeng, Pan; Teng, Yuancheng; Huang, Yi; Wu, Lang; Wang, Xiaohuan

    2014-09-01

    Praseodymium was used as the surrogate for trivalent minor actinide neptunium, and a complete series of pure monazite-type Ce1-xPrxPO4 (x = 0-1) solid solutions were successfully prepared by the solid state reaction. The effects of calcining temperature, holding time and Pr content on the structure of Ce1-xPrxPO4 solid solutions were investigated. The results show that although Pr6O11 (Pr23+Pr44+O11) exists two stabilized oxidation states, there has been no tetravalent praseodymium phosphate during the synthesis process. The optimized temperature for the synthesis of Ce0.8Pr0.2PO4 solid solution is more than 1100 °C, and a hypothetical reaction mechanism is also proposed. Besides, the crystalline grains coarsen as the increasing of holding time. The linear variation of unit cell parameters and a gradual hypsochromic shift in the Raman spectra are observed with the increase of Pr content, indicating that cerium is progressively replaced by praseodymium and Ce1-xPrxPO4 solid solutions were prepared.

  12. Performance of Thorium-Based Mixed Oxide Fuels for the Consumption of Plutonium and Minor Actinides in Current and Advanced Reactors

    SciTech Connect

    Weaver, Kevan Dean; Herring, James Stephen

    2002-06-01

    A renewed interest in thorium-based fuels has arisen lately based on the need for proliferation resistance, longer fuel cycles, higher burnup and improved wasteform characteristics. Recent studies have been directed toward homogeneously mixed, heterogeneously mixed, and seed-and-blanket thorium-uranium fuel cycles that rely on "in situ" use of the bred-in U-233. However, due to the higher initial enrichment required to achieve acceptable burnups, these fuels are encountering economic constraints. Thorium can nevertheless play a large role in the nuclear fuel cycle; particularly in the reduction of plutonium. While uranium-based mixedoxide (MOX) fuel will decrease the amount of plutonium, the reduction is limited due to the breeding of more plutonium (and higher actinides) from the U-238. Here we present calculational results and a comparison of the potential burnup of a thorium-based and uranium-based mixed oxide fuel in a light water reactor (LWR). Although the uranium-based fuels outperformed the thorium-based fuels in achievable burnup, a depletion comparison of the initially charged plutonium (both reactor and weapons grade) showed that the thorium-based fuels outperformed the uranium-based fuels by more that a factor of 2; where more than 70% of the total plutonium in the thorium-based fuel is consumed during the cycle. This is significant considering that the achievable burnup of the thorium-based fuels were 1.4 to 4.6 times less than the uranium-based fuels. Furthermore, use of a thorium-based fuel could also be used as a strategy for reducing the amount of long-lived nuclides (including the minor actinides), and thus the radiotoxicity in spent nuclear fuel. Although the breeding of U-233 is a concern, the presence of U-232 and its daughter products can aid in making this fuel self-protecting, and/or enough U-238 can be added to denature the fissile uranium. From these calculations, it appears that thorium-based fuel for plutonium incineration is superior as

  13. Safe management of actinides in the nuclear fuel cycle: Role of mineralogy

    NASA Astrophysics Data System (ADS)

    Ewing, Rodney C.

    2011-02-01

    During the past 60 years, more than 1800 metric tonnes of Pu, and substantial quantities of the "minor" actinides, such as Np, Am and Cm, have been generated in nuclear reactors. Some of these transuranium elements can be a source of energy in fission reactions (e.g., 239Pu), a source of fissile material for nuclear weapons (e.g., 239Pu and 237Np), and of environmental concern because of their long-half lives and radiotoxicity (e.g., 239Pu and 237Np). There are two basic strategies for the disposition of these heavy elements: (1) to "burn" or transmute the actinides using nuclear reactors or accelerators; (2) to "sequester" the actinides in chemically durable, radiation-resistant materials that are suitable for geologic disposal. There has been substantial interest in the use of actinide-bearing minerals, especially isometric pyrochlore, A 2B 2O 7 (A = rare earths; B = Ti, Zr, Sn, Hf), for the immobilization of actinides, particularly plutonium, both as inert matrix fuels and nuclear waste forms. Systematic studies of rare-earth pyrochlores have led to the discovery that certain compositions (B = Zr, Hf) are stable to very high doses of alpha-decay event damage. Recent developments in our understanding of the properties of heavy element solids have opened up new possibilities for the design of advanced nuclear fuels and waste forms.

  14. Fabrication and Pre-irradiation Characterization of a Minor Actinide and Rare Earth Containing Fast Reactor Fuel Experiment for Irradiation in the Advanced Test Reactor

    SciTech Connect

    Timothy A. Hyde

    2012-06-01

    The United States Department of Energy, seeks to develop and demonstrate the technologies needed to transmute the long-lived transuranic actinide isotopes contained in spent nuclear fuel into shorter lived fission products, thereby decreasing the volume of material requiring disposal and reducing the long-term radiotoxicity and heat load of high-level waste sent to a geologic repository. This transmutation of the long lived actinides plutonium, neptunium, americium and curium can be accomplished by first separating them from spent Light Water Reactor fuel using a pyro-metalurgical process, then reprocessing them into new fuel with fresh uranium additions, and then transmuted to short lived nuclides in a liquid metal cooled fast reactor. An important component of the technology is developing actinide-bearing fuel forms containing plutonium, neptunium, americium and curium isotopes that meet the stringent requirements of reactor fuels and materials.

  15. Actinides-1981

    SciTech Connect

    Not Available

    1981-09-01

    Abstracts of 134 papers which were presented at the Actinides-1981 conference are presented. Approximately half of these papers deal with electronic structure of the actinides. Others deal with solid state chemistry, nuclear physic, thermodynamic properties, solution chemistry, and applied chemistry.

  16. Nuclear waste forms for actinides

    PubMed Central

    Ewing, Rodney C.

    1999-01-01

    The disposition of actinides, most recently 239Pu from dismantled nuclear weapons, requires effective containment of waste generated by the nuclear fuel cycle. Because actinides (e.g., 239Pu and 237Np) are long-lived, they have a major impact on risk assessments of geologic repositories. Thus, demonstrable, long-term chemical and mechanical durability are essential properties of waste forms for the immobilization of actinides. Mineralogic and geologic studies provide excellent candidate phases for immobilization and a unique database that cannot be duplicated by a purely materials science approach. The “mineralogic approach” is illustrated by a discussion of zircon as a phase for the immobilization of excess weapons plutonium. PMID:10097054

  17. Dispositional logic

    SciTech Connect

    Zadeh, L.A.

    1988-01-01

    The applicability of conventional mathematical analysis (based on the combination of two-valued logic and probability theory) to problems in which human judgment, perception, or emotions play significant roles is considered theoretically. It is shown that dispositional logic, a branch of fuzzy logic, has particular relevance to the common-sense reasoning typical of human decision-making. The concepts of dispositionality and usuality are defined analytically, and a dispositional conjunctive rule and dispositional modus ponens are derived. 7 references.

  18. Dispositional logic

    NASA Technical Reports Server (NTRS)

    Le Balleur, J. C.

    1988-01-01

    The applicability of conventional mathematical analysis (based on the combination of two-valued logic and probability theory) to problems in which human judgment, perception, or emotions play significant roles is considered theoretically. It is shown that dispositional logic, a branch of fuzzy logic, has particular relevance to the common-sense reasoning typical of human decision-making. The concepts of dispositionality and usuality are defined analytically, and a dispositional conjunctive rule and dispositional modus ponens are derived.

  19. 25 CFR 11.1112 - Dispositional alternatives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... the minor reaches 18 years of age, unless the dispositional order was made within six months of the minor's eighteenth birthday, in which case the disposition may not continue for more than six months. (d... every six months to determine the continuing need for and appropriateness of placement, to determine...

  20. 25 CFR 11.1012 - Dispositional alternatives.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... was made within six months of the minor's eighteenth birthday or after the minor had reached 18 years of age, in which case the disposition may not continue for more than six months. (c) The dispositional order is to be reviewed at the children's court discretion, but at least once every six months....

  1. 33rd Actinide Separations Conference

    SciTech Connect

    McDonald, L M; Wilk, P A

    2009-05-04

    Welcome to the 33rd Actinide Separations Conference hosted this year by the Lawrence Livermore National Laboratory. This annual conference is centered on the idea of networking and communication with scientists from throughout the United States, Britain, France and Japan who have expertise in nuclear material processing. This conference forum provides an excellent opportunity for bringing together experts in the fields of chemistry, nuclear and chemical engineering, and actinide processing to present and discuss experiences, research results, testing and application of actinide separation processes. The exchange of information that will take place between you, and other subject matter experts from around the nation and across the international boundaries, is a critical tool to assist in solving both national and international problems associated with the processing of nuclear materials used for both defense and energy purposes, as well as for the safe disposition of excess nuclear material. Granlibakken is a dedicated conference facility and training campus that is set up to provide the venue that supports communication between scientists and engineers attending the 33rd Actinide Separations Conference. We believe that you will find that Granlibakken and the Lake Tahoe views provide an atmosphere that is stimulating for fruitful discussions between participants from both government and private industry. We thank the Lawrence Livermore National Laboratory and the United States Department of Energy for their support of this conference. We especially thank you, the participants and subject matter experts, for your involvement in the 33rd Actinide Separations Conference.

  2. Impact of Including Higher Actinides in Fast Reactor Transmutation Analyses

    SciTech Connect

    B. Forget; M. Asgari; R. Ferrer; S. Bays

    2007-09-01

    Previous fast reactor transmutation studies generally disregarded higher mass minor actinides beyond Cm-246 due to various considerations including deficiencies in nuclear cross-section data. Although omission of these higher mass actinides does not significantly impact the neutronic calculations and fuel cycle performance parameters follow-on neutron dose calculations related to fuel recycling, transportation and handling are significantly impacted. This report shows that including the minor actinides in the equilibrium fast reactor calculations will increase the predicted neutron emission by about 30%. In addition a sensitivity study was initiated by comparing the impact of different cross-section evaluation file for representing these minor actinides.

  3. Representing dispositions

    PubMed Central

    2011-01-01

    Dispositions and tendencies feature significantly in the biomedical domain and therefore in representations of knowledge of that domain. They are not only important for specific applications like an infectious disease ontology, but also as part of a general strategy for modelling knowledge about molecular interactions. But the task of representing dispositions in some formal ontological systems is fraught with several problems, which are partly due to the fact that Description Logics can only deal well with binary relations. The paper will discuss some of the results of the philosophical debate about dispositions, in order to see whether the formal relations needed to represent dispositions can be broken down to binary relations. Finally, we will discuss problems arising from the possibility of the absence of realizations, of multi-track or multi-trigger dispositions and offer suggestions on how to deal with them. PMID:21995952

  4. Actinide co-conversion by internal gelation

    SciTech Connect

    Robisson, Anne-Charlotte; Dauby, Jacques; Dumont-Shintu, Corinne; Machon, Estelle; Grandjean, Stephane

    2007-07-01

    Suitable microstructures and homogenous microspheres of actinide compounds are of interest for future nuclear fuel or transmutation target concepts to prevent the generation and dispersal of actinide powder. Sol-gel routes are being investigated as one of the possible solutions for producing these compounds. Preliminary work is described involving internal gelation to synthesize mixed compounds including minor actinides, particularly mixed actinide or mixed actinide-inert element compounds. A parameter study is discussed to highlight the importance of the initial broth composition for obtaining gel microspheres without major defects (cracks, craters, etc.). In particular, conditions are defined to produce gel beads from Zr(IV)/Y(III)/Ce(III) or Zr(IV)/An(III) systems. After gelation, the heat treatment of these microspheres is described for the purpose of better understanding the formation of cracks after calcination and verifying the effective synthesis of an oxide solid-solution. (authors)

  5. BTBPs versus BTPhens: some reasons for their differences in properties concerning the partitioning of minor actinides and the advantages of BTPhens.

    PubMed

    Lewis, Frank W; Harwood, Laurence M; Hudson, Michael J; Drew, Michael G B; Hubscher-Bruder, Véronique; Videva, Vladimira; Arnaud-Neu, Françoise; Stamberg, Karel; Vyas, Shyam

    2013-05-01

    Two members of the tetradentate N-donor ligand families 6,6'-bis(1,2,4-triazin-3-yl)-2,2'-bipyridine (BTBP) and 2,9-bis(1,2,4-triazin-3-yl)-1,10-phenanthroline (BTPhen) currently being developed for separating actinides from lanthanides have been studied. It has been confirmed that CyMe4-BTPhen 2 has faster complexation kinetics than CyMe4-BTBP 1. The values for the HOMO-LUMO gap of 2 are comparable with those of CyMe4-BTBP 1 for which the HOMO-LUMO gap was previously calculated to be 2.13 eV. The displacement of BTBP from its bis-lanthanum(III) complex by BTPhen was observed by NMR, and constitutes the only direct evidence for the greater thermodynamic stability of the complexes of BTPhen. NMR competition experiments suggest the following order of bis-complex stability: 1:2 bis-BTPhen complex ≥ heteroleptic BTBP/BTPhen 1:2 bis-complex > 1:2 bis-BTBP complex. Kinetics studies on some bis-triazine N-donor ligands using the stopped-flow technique showed a clear relationship between the rates of metal ion complexation and the degree to which the ligand is preorganized for metal binding. The BTBPs must overcome a significant (ca. 12 kcal mol(-1)) energy barrier to rotation about the central biaryl C-C axis in order to achieve the cis-cis conformation that is required to form a complex, whereas the cis-cis conformation is fixed in the BTPhens. Complexation thermodynamics and kinetics studies in acetonitrile show subtle differences between the thermodynamic stabilities of the complexes formed, with similar stability constants being found for both ligands. The first crystal structure of a 1:1 complex of CyMe4-BTPhen 2 with Y(NO3)3 is also reported. The metal ion is 10-coordinate being bonded to the tetradentate ligand 2 and three bidentate nitrate ions. The tetradentate ligand is nearly planar with angles between consecutive rings of 16.4(2)°, 6.4(2)°, 9.7(2)°, respectively. PMID:23614770

  6. Transmutation of actinides in power reactors.

    PubMed

    Bergelson, B R; Gerasimov, A S; Tikhomirov, G V

    2005-01-01

    Power reactors can be used for partial short-term transmutation of radwaste. This transmutation is beneficial in terms of subsequent storage conditions for spent fuel in long-term storage facilities. CANDU-type reactors can transmute the main minor actinides from two or three reactors of the VVER-1000 type. A VVER-1000-type reactor can operate in a self-service mode with transmutation of its own actinides. PMID:16604724

  7. 25 CFR 11.1112 - Dispositional alternatives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Dispositional alternatives. 11.1112 Section 11.1112 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1112 Dispositional alternatives. (a) If...

  8. 25 CFR 11.1112 - Dispositional alternatives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Dispositional alternatives. 11.1112 Section 11.1112 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1112 Dispositional alternatives. (a) If...

  9. 25 CFR 11.1112 - Dispositional alternatives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Dispositional alternatives. 11.1112 Section 11.1112 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1112 Dispositional alternatives. (a) If...

  10. 25 CFR 11.1112 - Dispositional alternatives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Dispositional alternatives. 11.1112 Section 11.1112 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Minor-in-Need-of-Care Procedure § 11.1112 Dispositional alternatives. (a) If...

  11. Environmental speciation of actinides.

    PubMed

    Maher, Kate; Bargar, John R; Brown, Gordon E

    2013-04-01

    Although minor in abundance in Earth's crust (U, 2-4 ppm; Th, 10-15 ppm) and in seawater (U, 0.003 ppm; Th, 0.0007 ppm), light actinides (Th, Pa, U, Np, Pu, Am, and Cm) are important environmental contaminants associated with anthropogenic activities such as the mining and milling of uranium ores, generation of nuclear energy, and storage of legacy waste resulting from the manufacturing and testing of nuclear weapons. In this review, we discuss the abundance, production, and environmental sources of naturally occurring and some man-made light actinides. As is the case with other environmental contaminants, the solubility, transport properties, bioavailability, and toxicity of actinides are dependent on their speciation (composition, oxidation state, molecular-level structure, and nature of the phase in which the contaminant element or molecule occurs). We review the aqueous speciation of U, Np, and Pu as a function of pH and Eh, their interaction with common inorganic and organic ligands in natural waters, and some of the common U-containing minerals. We also discuss the interaction of U, Np, Pu, and Am solution complexes with common Earth materials, including minerals, colloids, gels, natural organic matter (NOM), and microbial organisms, based on simplified model system studies. These surface interactions can inhibit (e.g., sorption to mineral surfaces, formation of insoluble biominerals) or enhance (e.g., colloid-facilitated transport) the dispersal of light actinides in the biosphere and in some cases (e.g., interaction with dissimilatory metal-reducing bacteria, NOM, or Mn- and Fe-containing minerals) can modify the oxidation states and, consequently, the behavior of redox-sensitive light actinides (U, Np, and Pu). Finally, we review the speciation of U and Pu, their chemical transformations, and cleanup histories at several U.S. Department of Energy field sites that have been used to mill U ores, produce fissile materials for reactors and weapons, and store

  12. Development of the Actinide-Lanthanide Separation (ALSEP) Process

    SciTech Connect

    Lumetta, Gregg J.; Carter, Jennifer C.; Niver, Cynthia M.; Gelis, Artem V.

    2014-09-30

    Separating the minor actinide elements (Am and Cm) from acidic high-level raffinates arising from the reprocessing of irradiated nuclear fuel is an important step in closing the nuclear fuel cycle. Most proposed approaches to this problem involve two solvent extraction steps: 1) co-extraction of the trivalent lanthanides and actinides, followed by 2) separation of the actinides from the lanthanides. The objective of our work is to develop a single solvent-extraction process for isolating the minor actinide elements. We report here a solvent containing N,N,N',N'-tetra(2 ethylhexyl)diglycolamide (T2EHDGA) combined with 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]) that can be used to separate the minor actinides in a single solvent-extraction process. T2EHDGA serves to co-extract the trivalent actinide and lanthanide ions from nitric acid solution. Switching the aqueous phase chemistry to a citrate buffered solution of N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid at pH 2.5 to 4 results in selective transfer of the actinides to the aqueous phase, thus affecting separation of the actinides from the lanthanides. Separation factors between the lanthanides and actinides are approximately 20 in the pH range of 3 to 4, and the distribution ratios are not highly dependent on the pH in this system.

  13. Actinide metal processing

    DOEpatents

    Sauer, Nancy N.; Watkin, John G.

    1992-01-01

    A process of converting an actinide metal such as thorium, uranium, or plnium to an actinide oxide material by admixing the actinide metal in an aqueous medium with a hypochlorite as an oxidizing agent for sufficient time to form the actinide oxide material and recovering the actinide oxide material is provided together with a low temperature process of preparing an actinide oxide nitrate such as uranyl nitrte. Additionally, a composition of matter comprising the reaction product of uranium metal and sodium hypochlorite is provided, the reaction product being an essentially insoluble uranium oxide material suitable for disposal or long term storage.

  14. Actinide metal processing

    SciTech Connect

    Sauer, N.N.; Watkin, J.G.

    1992-03-24

    A process for converting an actinide metal such as thorium, uranium, or plutonium to an actinide oxide material by admixing the actinide metal in an aqueous medium with a hypochlorite as an oxidizing agent for sufficient time to form the actinide oxide material and recovering the actinide oxide material is described together with a low temperature process for preparing an actinide oxide nitrate such as uranyl nitrate. Additionally, a composition of matter comprising the reaction product of uranium metal and sodium hypochlorite is provided, the reaction product being an essentially insoluble uranium oxide material suitable for disposal or long term storage.

  15. Actinide metal processing

    SciTech Connect

    Sauer, N.N.; Watkin, J.G.

    1991-04-05

    This invention is comprised of a process of converting an actinide metal such as thorium, uranium, or plutonium to an actinide oxide material by admixing the actinide metal in an aqueous medium with a hypochlorite as an oxidizing agent for sufficient time to form the actinide oxide material and recovering the actinide oxide material is provided together with a low temperature process of preparing an actinide oxide nitrate such as uranyl nitrate. Additionally, a composition of matter comprising the reaction product of uranium metal and sodium hypochlorite is provided, the reaction product being an essentially insoluble uranium oxide material suitable for disposal or long term storage.

  16. Minior Actinide Doppler Coefficient Measurement Assessment

    SciTech Connect

    Nolan E. Hertel; Dwayne Blaylock

    2008-04-10

    The "Minor Actinide Doppler Coefficient Measurement Assessment" was a Department of Energy (DOE) U-NERI funded project intended to assess the viability of using either the FLATTOP or the COMET critical assembly to measure high temperature Doppler coefficients. The goal of the project was to calculate using the MCNP5 code the gram amounts of Np-237, Pu-238, Pu-239, Pu-241, AM-241, AM-242m, Am-243, and CM-244 needed to produce a 1E-5 in reactivity for a change in operating temperature 800C to 1000C. After determining the viability of using the assemblies and calculating the amounts of each actinide an experiment will be designed to verify the calculated results. The calculations and any doncuted experiments are designed to support the Advanced Fuel Cycle Initiative in conducting safety analysis of advanced fast reactor or acceoerator-driven transmutation systems with fuel containing high minor actinide content.

  17. 25 CFR 11.1013 - Modification of dispositional order.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... OFFENSES AND LAW AND ORDER CODE Juvenile Offender Procedure § 11.1013 Modification of dispositional order... minor or the minor's parents, guardian or custodian. (c) If the modification involves a change of...'s court shall review the performance of the minor, the minor's parents, guardian or custodian,...

  18. Actinide Lanthanide Separation Process – ALSEP

    SciTech Connect

    Gelis, Artem V.; Lumetta, Gregg J.

    2014-01-29

    Separation of the minor actinides (Am, Cm) from the lanthanides at an industrial scale remains a significant technical challenge for closing the nuclear fuel cycle. To increase the safety of used nuclear fuel (UNF) reprocessing, as well as reduce associated costs, a novel solvent extraction process has been developed. The process allows for partitioning minor actinides, lanthanides and fission products following uranium/plutonium/neptunium removal; minimizing the number of separation steps, flowsheets, chemical consumption, and waste. This new process, Actinide Lanthanide SEParation (ALSEP), uses an organic solvent consisting of a neutral diglycolamide extractant, either N,N,N',N'-tetra(2 ethylhexyl)diglycolamide (T2EHDGA) or N,N,N',N'-tetraoctyldiglycolamide (TODGA), and an acidic extractant 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]), dissolved in an aliphatic diluent (e.g. n-dodecane). The An/Ln co-extraction is conducted from moderate-to-strong nitric acid, while the selective stripping of the minor actinides from the lanthanides is carried out using a polyaminocarboxylic acid/citrate buffered solution at pH anywhere between 3 and 4.5. The extraction and separation of the actinides from the fission products is very effective in a wide range of HNO3 concentrations and the minimum separation factors for lanthanide/Am exceed 30 for Nd/Am, reaching > 60 for Eu/Am under some conditions. The experimental results presented here demonstrate the great potential for a combined system, consisting of a neutral extractant such as T2EHDGA or TODGA, and an acidic extractant such as HEH[EHP], for separating the minor actinides from the lanthanides.

  19. Actinide sulfite tetrahydrate and actinide oxysulfite tetrahydrate

    SciTech Connect

    Baugh, D.; Watt, G.

    1980-07-08

    A compound is prepared that comprises an actinide sulfite tetrahydrate selected from the group consisting of uranium (IV) sulfite tetrahydrate and plutonium (IV) sulfite tetrahydrate. A compound is also prepared that comprises an actinide oxysulfite tetrahydrate selected from the group consisting of uranium (IV) oxysulfite tetrahydrate and plutonium (IV) oxysulfite tetrahydrate

  20. Actinide-ion sensor

    DOEpatents

    Li, Shelly X; Jue, Jan-fong; Herbst, Ronald Scott; Herrmann, Steven Douglas

    2015-01-13

    An apparatus for the real-time, in-situ monitoring of actinide-ion concentrations. A working electrolyte is positioned within the interior of a container. The working electrolyte is separated from a reference electrolyte by a separator. A working electrode is at least partially in contact with the working electrolyte. A reference electrode is at least partially in contact with the reference electrolyte. A voltmeter is electrically connected to the working electrode and the reference electrode. The working electrolyte comprises an actinide-ion of interest. The separator is ionically conductive to the actinide-ion of interest. The separator comprises an actinide, Zr, and Nb. Preferably, the actinide of the separator is Am or Np, more preferably Pu. In one embodiment, the actinide of the separator is the actinide of interest. In another embodiment, the separator further comprises P and O.

  1. Actinide extraction methods

    DOEpatents

    Peterman, Dean R [Idaho Falls, ID; Klaehn, John R [Idaho Falls, ID; Harrup, Mason K [Idaho Falls, ID; Tillotson, Richard D [Moore, ID; Law, Jack D [Pocatello, ID

    2010-09-21

    Methods of separating actinides from lanthanides are disclosed. A regio-specific/stereo-specific dithiophosphinic acid having organic moieties is provided in an organic solvent that is then contacted with an acidic medium containing an actinide and a lanthanide. The method can extend to separating actinides from one another. Actinides are extracted as a complex with the dithiophosphinic acid. Separation compositions include an aqueous phase, an organic phase, dithiophosphinic acid, and at least one actinide. The compositions may include additional actinides and/or lanthanides. A method of producing a dithiophosphinic acid comprising at least two organic moieties selected from aromatics and alkyls, each moiety having at least one functional group is also disclosed. A source of sulfur is reacted with a halophosphine. An ammonium salt of the dithiophosphinic acid product is precipitated out of the reaction mixture. The precipitated salt is dissolved in ether. The ether is removed to yield the dithiophosphinic acid.

  2. Research in actinide chemistry

    SciTech Connect

    Choppin, G.R.

    1993-01-01

    This research studies the behavior of the actinide elements in aqueous solution. The high radioactivity of the transuranium actinides limits the concentrations which can be studied and, consequently, limits the experimental techniques. However, oxidation state analogs (trivalent lanthanides, tetravalent thorium, and hexavalent uranium) do not suffer from these limitations. Behavior of actinides in the environment are a major USDOE concern, whether in connection with long-term releases from a repository, releases from stored defense wastes or accidental releases in reprocessing, etc. Principal goal of our research was expand the thermodynamic data base on complexation of actinides by natural ligands (e.g., OH[sup [minus

  3. Actinide Targets for Neutron Cross Section Measurements

    SciTech Connect

    John D. Baker; Christopher A. McGrath

    2006-10-01

    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 to correct this. One of the initial hurdles has been to produce well-characterized, highly isotopically enriched, and chemically pure actinide targets on thin backings. Using a combination of resurrected techniques and new developments, we have made a series of targets including highly enriched 239Pu, 240Pu, and 242Pu. Thus far, we have electrodeposited these actinide targets. In the future, we plan to study reductive distillation to achieve homogeneous, adherent targets on thin metal foils and polymer backings. As we move forward, separated isotopes become scarcer, and safety concerns become greater. The chemical purification and electodeposition techniques will be described.

  4. Separation of actinides from spent nuclear fuel: A review.

    PubMed

    Veliscek-Carolan, Jessica

    2016-11-15

    This review summarises the methods currently available to extract radioactive actinide elements from solutions of spent nuclear fuel. This separation of actinides reduces the hazards associated with spent nuclear fuel, such as its radiotoxicity, volume and the amount of time required for its' radioactivity to return to naturally occurring levels. Separation of actinides from environmental water systems is also briefly discussed. The actinide elements typically found in spent nuclear fuel include uranium, plutonium and the minor actinides (americium, neptunium and curium). Separation methods for uranium and plutonium are reasonably well established. On the other hand separation of the minor actinides from lanthanide fission products also present in spent nuclear fuel is an ongoing challenge and an area of active research. Several separation methods for selective removal of these actinides from spent nuclear fuel will be described. These separation methods include solvent extraction, which is the most commonly used method for radiochemical separations, as well as the less developed but promising use of adsorption and ion-exchange materials. PMID:27427893

  5. Actinide recovery process

    DOEpatents

    Muscatello, Anthony C.; Navratil, James D.; Saba, Mark T.

    1987-07-28

    Process for the removal of plutonium polymer and ionic actinides from aqueous solutions by absorption onto a solid extractant loaded on a solid inert support such as polystyrenedivinylbenzene. The absorbed actinides can then be recovered by incineration, by stripping with organic solvents, or by acid digestion. Preferred solid extractants are trioctylphosphine oxide and octylphenyl-N,N-diisobutylcarbamoylmethylphosphine oxide and the like.

  6. Dispositional greed.

    PubMed

    Seuntjens, Terri G; Zeelenberg, Marcel; van de Ven, Niels; Breugelmans, Seger M

    2015-06-01

    Greed is an important motive: it is seen as both productive (a source of ambition; the motor of the economy) and destructive (undermining social relationships; the cause of the late 2000s financial crisis). However, relatively little is known about what greed is and does. This article reports on 5 studies that develop and test the 7-item Dispositional Greed Scale (DGS). Study 1 (including 4 separate samples from 2 different countries, total N = 6092) provides evidence for the construct and discriminant validity of the DGS in terms of positive correlations with maximization, self-interest, envy, materialism, and impulsiveness, and negative correlations with self-control and life satisfaction. Study 2 (N = 290) presents further evidence for discriminant validity, finding that the DGS predicts greedy behavioral tendencies over and above materialism. Furthermore, the DGS predicts economic behavior: greedy people allocate more money to themselves in dictator games (Study 3, N = 300) and ultimatum games (Study 4, N = 603), and take more in a resource dilemma (Study 5, N = 305). These findings shed light on what greed is and does, how people differ in greed, and how greed can be measured. In addition, they show the importance of greed in economic behavior and provide directions for future studies. PMID:25664899

  7. Thermodynamic Properties of Actinides and Actinide Compounds

    NASA Astrophysics Data System (ADS)

    Konings, Rudy J. M.; Morss, Lester R.; Fuger, Jean

    The necessity of obtaining accurate thermodynamic quantities for the actinide elements and their compounds was recognized at the outset of the Manhattan Project, when a dedicated team of scientists and engineers initiated the program to exploit nuclear energy for military purposes. Since the end of World War II, both fundamental and applied objectives have motivated a great deal of further study of actinide thermodynamics. This chapter brings together many research papers and critical reviews on this subject. It also seeks to assess, to systematize, and to predict important properties of the actinide elements, ions, and compounds, especially for species in which there is significant interest and for which there is an experimental basis for the prediction.

  8. Method for preparing actinide nitrides

    DOEpatents

    Bryan, G.H.; Cleveland, J.M.; Heiple, C.R.

    1975-12-01

    Actinide nitrides, and particularly plutonium and uranium nitrides, are prepared by reacting an ammonia solution of an actinide compound with an ammonia solution of a reactant or reductant metal, to form finely divided actinide nitride precipitate which may then be appropriately separated from the solution. The actinide nitride precipitate is particularly suitable for forming nuclear fuels.

  9. The Dispositions Improvement Process

    ERIC Educational Resources Information Center

    Brewer, Robin D.; Lindquist, Cynthia; Altemueller, Lisa

    2011-01-01

    Globally, teacher dispositions along with knowledge and skills continue to be the focal point of teacher education programs. Teachers influence children's development and therefore dispositions are a universal concern. For the past 20 years in the United States, teacher education programs have assessed dispositions. We, however, must now also use…

  10. Research in actinide chemistry

    SciTech Connect

    Not Available

    1991-01-01

    This report contains research results on studies of inorganic and organic complexes of actinide and lanthanide elements. Special attention is given to complexes of humic acids and to spectroscopic studies.

  11. Thermochemistry of the actinides

    SciTech Connect

    Kleinschmidt, P.D.

    1993-10-01

    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 is calculated based on this thermochemical data.

  12. PRODUCTION OF ACTINIDE METAL

    DOEpatents

    Knighton, J.B.

    1963-11-01

    A process of reducing actinide oxide to the metal with magnesium-zinc alloy in a flux of 5 mole% of magnesium fluoride and 95 mole% of magnesium chloride plus lithium, sodium, potassium, calcium, strontium, or barium chloride is presented. The flux contains at least 14 mole% of magnesium cation at 600-- 900 deg C in air. The formed magnesium-zinc-actinide alloy is separated from the magnesium-oxide-containing flux. (AEC)

  13. Actinide recovery process

    DOEpatents

    Muscatello, A.C.; Navratil, J.D.; Saba, M.T.

    1985-06-13

    Process for the removal of plutonium polymer and ionic actinides from aqueous solutions by absorption onto a solid extractant loaded on a solid inert support such as polystyrene-divinylbenzene. The absorbed actinides can then be recovered by incineration, by stripping with organic solvents, or by acid digestion. Preferred solid extractants are trioctylphosphine oxide and octylphenyl-N,N-diisobutylcarbamoylmethylphosphine oxide and the like. 2 tabs.

  14. Actinide and lanthanide separation process (ALSEP)

    SciTech Connect

    Guelis, Artem V.

    2013-01-15

    The process of the invention is the separation of minor actinides from lanthanides in a fluid mixture comprising, fission products, lanthanides, minor actinides, rare earth elements, nitric acid and water by addition of an organic chelating aid to the fluid; extracting the fluid with a solvent comprising a first extractant, a second extractant and an organic diluent to form an organic extractant stream and an aqueous raffinate. Scrubbing the organic stream with a dicarboxylic acid and a chelating agent to form a scrubber discharge. The scrubber discharge is stripped with a simple buffering agent and a second chelating agent in the pH range of 2.5 to 6.1 to produce actinide and lanthanide streams and spent organic diluents. The first extractant is selected from bis(2-ethylhexyl)hydrogen phosphate (HDEHP) and mono(2-ethylhexyl)2-ethylhexyl phosphonate (HEH(EHP)) and the second extractant is selected from N,N,N,N-tetra-2-ethylhexyl diglycol amide (TEHDGA) and N,N,N',N'-tetraoctyl-3-oxapentanediamide (TODGA).

  15. Nonaqueous actinide hydride dissolution and production of actinide $beta$- diketonates

    DOEpatents

    Crisler, L.R.

    1975-11-11

    Actinide beta-diketonate complex molecular compounds are produced by reacting a beta-diketone compound with a hydride of the actinide material in a mixture of carbon tetrachloride and methanol. (auth)

  16. Thoria, a quasi-inert matrix for actinides dispositions

    NASA Astrophysics Data System (ADS)

    Barrier, D.; Bukaemskiy, A. A.; Modolo, G.

    2006-06-01

    Thoria is a promising matrix for the immobilisation of plutonium in either a burning or a conditioning strategy. The aim of this work is twofold: to study the impact of the addition of plutonium, simulated with cerium, on the physico-mechanical properties of thoria and to investigate the possibility of synthesising ceramics employing simple fabrication routes. Th1-xCexO2 powders with ceria concentrations from 0 to 75% were synthesised by the co-precipitation method. The properties of the powders, such as thermal and crystallisation behaviour, were determined as a function of ceria content and calcination temperature. (Th, Ce)O2 pellets containing up to 20% ceria were compacted from non-ground 675 K calcined powder using a double repressing method. The pellets have densities of up to 0.98 TD and a homogeneous surface with well-distributed pores. The main mechanical properties, such as microhardness and fracture toughness, were also investigated as a function of ceria content.

  17. Microbial Transformations of Actinides and Other Radionuclides

    SciTech Connect

    Francis,A.J.; Dodge, C. J.

    2009-01-07

    Microorganisms can affect the stability and mobility of the actinides and other radionuclides released from nuclear fuel cycle and from nuclear fuel reprocessing plants. Under appropriate conditions, microorganisms can alter the chemical speciation, solubility and sorption properties and thus could increase or decrease the concentrations of radionuclides in solution in the environment and the bioavailability. Dissolution or immobilization of radionuclides is brought about by direct enzymatic action or indirect non-enzymatic action of microorganisms. Although the physical, chemical, and geochemical processes affecting dissolution, precipitation, and mobilization of radionuclides have been extensively investigated, we have only limited information on the effects of microbial processes and biochemical mechanisms which affect the stability and mobility of radionuclides. The mechanisms of microbial transformations of the major and minor actinides U, Pu, Cm, Am, Np, the fission products and other radionuclides such as Ra, Tc, I, Cs, Sr, under aerobic and anaerobic conditions in the presence of electron donors and acceptors are reviewed.

  18. Irradiaton of Metallic and Oxide Fuels for Actinide Transmutation in the ATR

    SciTech Connect

    Heather J. MacLean; Steven L. Hayes

    2007-09-01

    Metallic fuels containing minor actinides and rare earth additions have been fabricated and are prepared for irradiation in the ATR, scheduled to begin during the summer of 2007. Oxide fuels containing minor actinides are being fabricated and will be ready for irradiation in ATR, scheduled to begin during the summer of 2008. Fabrication and irradiation of these fuels will provide detailed studies of actinide transmutation in support of the Global Nuclear Energy Partnership. These fuel irradiations include new fuel compositions that have never before been tested. Results from these tests will provide fundamental data on fuel irradiation performance and will advance the state of knowledge for transmutation fuels.

  19. The Disposition to Learn.

    ERIC Educational Resources Information Center

    Katz, Lilian

    1988-01-01

    Lectures and workbooks cannot instill curiosity and continuous interest or the disposition to respond to experiences in certain ways. This article examines sabateurs of the learning disposition (such as reinforcing learned stupidity and using rewards that suppress interest) and suggests curriculum strategies to engage young minds, such as using…

  20. Actinide management with commercial fast reactors

    NASA Astrophysics Data System (ADS)

    Ohki, Shigeo

    2015-12-01

    The capability of plutonium-breeding and minor-actinide (MA) transmutation in the Japanese commercial sodium-cooled fast reactor offers one of practical solutions for obtaining sustainable energy resources as well as reducing radioactive toxicity and inventory. The reference core design meets the requirement of flexible breeding ratio from 1.03 to 1.2. The MA transmutation amount has been evaluated as 50-100 kg/GWey if the MA content in fresh fuel is 3-5 wt%, where about 30-40% of initial MA can be transmuted in the discharged fuel.

  1. Actinide management with commercial fast reactors

    SciTech Connect

    Ohki, Shigeo

    2015-12-31

    The capability of plutonium-breeding and minor-actinide (MA) transmutation in the Japanese commercial sodium-cooled fast reactor offers one of practical solutions for obtaining sustainable energy resources as well as reducing radioactive toxicity and inventory. The reference core design meets the requirement of flexible breeding ratio from 1.03 to 1.2. The MA transmutation amount has been evaluated as 50-100 kg/GW{sub e}y if the MA content in fresh fuel is 3-5 wt%, where about 30-40% of initial MA can be transmuted in the discharged fuel.

  2. Research in actinide chemistry

    SciTech Connect

    Not Available

    1989-01-01

    Research continued to be focused broadly on the chemistry of the actinide cations in solution. While the direct concern is the actinide elements, their radioactivity limits the techniques which can be applied to their study. A major area of interest continues to be the thermodynamics of interaction of the f-elements with a broad spectrum of inorganic and organic ligands. Solvent extraction (for tracer levels), potentiometric and calorimetric titration and absorption spectrometry have been used to obtain stability constants and the associated enthalpy and entropy changes for complexation. A number of studies were performed to provide a better data base and a better understanding of the more significant species determining the behavior of actinides in natural waters (e.g., hydrolysis and silicate interaction). A second major area has been kinetics. NpO{sub 2}{sup 2+} reduction by hydroxy and carboxylic acids was studied to obtain an understanding of how such functional groups in humic substances may influence actinyl redox. The kinetics of dissociation of UO{sub 2}{sup 2+} and Ln{sup 3+} (La{sup 3+} = lanthanide element cations) from synthetic polyelectrolytes and humics provided significantly increased understanding of actinide complexation by these macromolecules. A third area of activity used laser induced fluorescence to study the hydration state of Eu(III) in a number of systems. Finally, several other studies, not in these major areas, were conducted. These included investigation of NpO{sub 2}{sup +} cation-cation complexes, the extraction of Am(III) by MX (M = Li, Na, NH{sub 4}{sup +}, K{sup +}; X = ClO{sub 4}{sup {minus}}, Cl{sup {minus}}, NO{sub 3}{sup {minus}}, BrO{sub 3}{sup {minus}}) over a concentration range from 0.01 M to saturated and the thermodynamics of synergistic extraction of actinides by crown ethers and {beta}-diketonates. 23 refs., 1 fig.

  3. Device for Detecting Actinides, Method for Detecting Actinides

    SciTech Connect

    Stevens, Fred J.; Wilkins-Stevens, Priscilla

    1998-10-29

    A heavy metal detector is provided comprising a first molecule and a second molecule, whereby the first and second molecules interact in a predetermined manner; a first region on the first molecule adapted to interact with an actinide; and a second region on the second molecule adapted to interact with the actinide, whereby the interactions of the actinide with the regions effect the predetermined manner of interaction between the molecules.

  4. Novel Separation of Actinides

    SciTech Connect

    Mariella, R

    2011-02-17

    The separation of actinides and other elements of interest for nuclear forensics and threat reduction is currently performed using decades-old chemistries and ion-exchange columns. We propose to determine the technical feasibility of a novel method for separating actinide ions in solution. This method is based upon isotachophoresis (ITP), which has been applied in the purification of pharmaceuticals and other biochemical applications. This technique has the potential to separate inorganic ions more effectively than existing methods, which is key to analyzing very small samples. We will perform a quantitative assessment of the effectiveness of specific isotachophoretic approaches including predicting the physical and chemical properties, such as ion mobility, of inorganic ions under specific solvent conditions using a combination of ab initio calculations and semi-empirical methods. We expect to obtain a thorough understanding of the analytical systems parameters under which ITP is most effective for the separation of inorganic samples, including the influence of the double layer surrounding actinide ions, the Debye length for different ions and ion complexes, and Debye-Hueckel limits. Inorganic separations are key to nuclear forensics for countering terrorism and nuclear proliferation. If found to be feasible and potentially superior to currently used separation approaches, ITP could provide the conceptual basis for an improved means to separate samples of nuclear explosion debris for nuclear forensic analysis, in support of the Laboratory's missions in homeland and national security.

  5. Actinide transmutation in a thermal reactor

    SciTech Connect

    Facchini, A.; Sanjust, V.

    1993-12-31

    The long term radiotoxicity of nuclear wastes may be substantially reduced by long irradiation in thermal reactors. Preliminary calculations showed that appreciable quantities of the minor actinides and long lived fission products may be recycled in a power PWR, and that, a few centuries after 20--30 years of irradiation, they reach radiotoxicity levels comparable to those of the uranium quantity required to make the corresponding fuel amount. The purpose of the present work is to investigate the conceptual possibility of reducing the level of the long term radiotoxicity, due to Minor Actinides and Long-Lived Fission Products (MA/LLFP) produced in UO{sub 2} fuel, by long irradiation of them in a power PWR. More precisely the authors pursued the objective of determining what fraction of the MA/LLFP mixture produced in a 1,000 MWe PWR during its whole life, may be burned in a similar power reactor. A waste burning efficiency has been considered satisfactory if the long term radiotoxicity of the MA/LLFP contained in a given quantity of spent fuel reaches, a few centuries after its irradiation, the level corresponding to that of the amount of natural uranium required to produce the same quantity of fresh fuel. This waiting time is in fact necessary in any case for cooling the other fission products to a sufficiently low radioactivity level and is a time span not unreasonable when considering man-made barriers against the radionuclide diffusion into the biosphere.

  6. PROCESS OF PRODUCING ACTINIDE METALS

    DOEpatents

    Magel, T.T.

    1959-07-14

    The preparation of actinide metals in workable, coherent form is described. In general, the objects of the invention are achieved by heating a mixture of an oxide and a halide of an actinide metal such as uranium with an alkali metal on alkaline earth metal reducing agent in the presence of iodine.

  7. An Evaluation of Single Phase Ceramic Formulations for Plutonium Disposition

    SciTech Connect

    Stennett, Martin C.; Hyatt, Neil C.; Maddrell, Ewan R.; Scales, Charlie R.; Livens, Francis R.; Gilbert, Matthew

    2007-07-01

    Ceramics are promising potential hosts for the immobilization of actinide containing wastes. Work has been reported in the literature on multiphase systems, such as SYNROC [1], and on single phase systems such as pyrochlores [2] and zirconia [3], but assessment of the different waste-forms by direct comparison of literature data is not always easy due to the different processing and fabrication routes employed. In this study a potential range of different ceramic systems were investigated for plutonium disposition using the same processing scheme. Durable actinide containing minerals exist in nature and provided excellent target phases for the titanate, zirconate, silicate and phosphate based formulations examined here [4]. The Ce solid solution limits for each particular substitution mechanism were established and the processing parameters required to produce high quality ceramic specimens were optimised. Importantly, this was achieved within the constraints of a generic processing route suitable for fabrication of Pu bearing samples. (authors)

  8. Sample results from the integrated salt disposition program macrobatch 6 tank 21H qualifications MST solids sample

    SciTech Connect

    Peters, T. B.

    2013-02-26

    Savannah River National Laboratory (SRNL) performed experiments on qualification material for use in the Integrated Salt Disposition Program (ISDP) Batch 6 processing. As part of this qualification work, SRNL performed an Actinide Removal Process (ARP) test. From this test, the residual monosodium titanate (MST) was analyzed for radionuclide uptake. The results of these analyses are reported and are within historical precedent.

  9. Actinide halide complexes

    DOEpatents

    Avens, L.R.; Zwick, B.D.; Sattelberger, A.P.; Clark, D.L.; Watkin, J.G.

    1992-11-24

    A compound is described of the formula MX[sub n]L[sub m] wherein M is a metal atom selected from the group consisting of thorium, plutonium, neptunium or americium, X is a halide atom, n is an integer selected from the group of three or four, 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 an integer selected from the group of three or four for monodentate ligands or is the integer two for bidentate ligands, where the sum of n+m equals seven or eight for monodentate ligands or five or six for bidentate ligands. A compound of the formula MX[sub n] wherein M, X, and n are as previously defined, and a process of preparing such actinide metal compounds are described including admixing the actinide metal in an aprotic Lewis base as a coordinating solvent in the presence of a halogen-containing oxidant.

  10. Actinide halide complexes

    DOEpatents

    Avens, Larry R.; Zwick, Bill D.; Sattelberger, Alfred P.; Clark, David L.; Watkin, John G.

    1992-01-01

    A compound of the formula MX.sub.n L.sub.m wherein M is a metal atom selected from the group consisting of thorium, plutonium, neptunium or americium, X is a halide atom, n is an integer selected from the group of three or four, 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 an integer selected from the group of three or four for monodentate ligands or is the integer two for bidentate ligands, where the sum of n+m equals seven or eight for monodentate ligands or five or six for bidentate ligands, a compound of the formula MX.sub.n wherein M, X, and n are as previously defined, and a process of preparing such actinide metal compounds including admixing the actinide metal in an aprotic Lewis base as a coordinating solvent in the presence of a halogen-containing oxidant, are provided.

  11. Dispositions in Action: Do Dispositions Make a Difference in Practice?

    ERIC Educational Resources Information Center

    Thornton, Holly

    2006-01-01

    The discourse on teacher quality has centered on issues of teacher knowledge and teacher skill, yet a third element that is central to all professional standards is teacher dispositions. Although there is no consensus about a definition of teacher dispositions, there are several models in use regarding how dispositions are being addressed. Most…

  12. MINIMIZING WASTE AND COST IN DISPOSITION OF LEGACY RESIDUES

    SciTech Connect

    J. BALKEY; M. ROBINSON

    2001-05-01

    Research is being conducted at the Los Alamos National Laboratory (LANL) which is directed toward development of a quantitative basis for disposition of actinide-bearing process residues (both legacy residues and residues generated from ongoing programmatic operations). This research is focused in two directions: (1) identifying minimum negative consequence (waste, dose, cost) dispositions working within regulatory safeguards termination criteria, and (2) evaluating logistics/consequences of across-the-board residue discards such as authorized at Rocky Flats under a safeguards termination variance. The first approach emphasizes Laboratory commitments to environmental stewardship, worker safety, and fiscal responsibility. This approach has been described as the Plutonium Disposition Methodology (PDM) in deference to direction provided by DOE Albuquerque. The second approach is born of the need to expedite removal of residues from storage for programmatic and reasons and residue storage safety concerns. Any disposition path selected must preserve the legal distinction between residues as Special Nuclear Material (SNM) and discardable materials as waste in order to insure the continuing viability of Laboratory plutonium processing facilities for national security operations.

  13. Managing Inventories of Heavy Actinides

    SciTech Connect

    Wham, Robert M; Patton, Bradley D

    2011-01-01

    The Department of Energy (DOE) has stored a limited inventory of heavy actinides contained in irradiated targets, some partially processed, at the Savannah River Site (SRS) and Oak Ridge National Laboratory (ORNL). The 'heavy actinides' of interest include plutonium, americium, and curium isotopes; specifically 242Pu and 244Pu, 243Am, and 244/246/248Cm. No alternate supplies of these heavy actinides and no other capabilities for producing them are currently available. Some of these heavy actinide materials are important for use as feedstock for producing heavy isotopes and elements needed for research and commercial application. The rare isotope 244Pu is valuable for research, environmental safeguards, and nuclear forensics. Because the production of these heavy actinides was made possible only by the enormous investment of time and money associated with defense production efforts, the remaining inventories of these rare nuclear materials are an important part of the legacy of the Nuclear Weapons Program. Significant unique heavy actinide inventories reside in irradiated Mark-18A and Mark-42 targets at SRS and ORNL, with no plans to separate and store the isotopes for future use. Although the costs of preserving these heavy actinide materials would be considerable, for all practical purposes they are irreplaceable. The effort required to reproduce these heavy actinides today would likely cost billions of dollars and encompass a series of irradiation and chemical separation cycles for at least 50 years; thus, reproduction is virtually impossible. DOE has a limited window of opportunity to recover and preserve these heavy actinides before they are disposed of as waste. A path forward is presented to recover and manage these irreplaceable National Asset materials for future use in research, nuclear forensics, and other potential applications.

  14. Actinide Burning in CANDU Reactors

    SciTech Connect

    Hyland, B.; Dyck, G.R.

    2007-07-01

    Actinide burning in CANDU reactors has been studied as a method of reducing the actinide content of spent nuclear fuel from light water reactors, and thereby decreasing the associated long term decay heat load. In this work simulations were performed of actinides mixed with natural uranium to form a mixed oxide (MOX) fuel, and also mixed with silicon carbide to form an inert matrix (IMF) fuel. Both of these fuels were taken to a higher burnup than has previously been studied. The total transuranic element destruction calculated was 40% for the MOX fuel and 71% for the IMF. (authors)

  15. Grouped actinide separation in advanced nuclear fuel cycles

    SciTech Connect

    Glatz, J.P.; Malmbeck, R.; Ougier, M.; Soucek, P.; Murakamin, T.; Tsukada, T.; Koyama, T.

    2013-07-01

    Aiming at cleaner waste streams (containing only the short-lived fission products) a partitioning and transmutation (P-T) scheme can significantly reduce the quantities of long-lived radionuclides consigned to waste. Many issues and options are being discussed and studied at present in view of selecting the optimal route. The choice is between individual treatment of the relevant elements and a grouped treatment of all actinides together. In the European Collaborative Project ACSEPT (Actinide recycling by Separation and Transmutation), grouped separation options derived from an aqueous extraction or from a dry pyroprocessing route were extensively investigated. Successful demonstration tests for both systems have been carried out in the frame of this project. The aqueous process called GANEX (Grouped Actinide Extraction) is composed of 2 cycles, a first one to recover the major part of U followed by a co-extraction of Np, Pu, Am, and Cm altogether. The pyro-reprocessing primarily applicable to metallic fuels such as the U-Pu-Zr alloy originally developed by the Argonne National Laboratory (US) in the mid 1980s, has also been applied to the METAPHIX fuels containing up to 5% of minor actinides and 5% of lanthanides (e.g. U{sub 60}Pu{sub 20}-Zr{sub 10}Am{sub 2}Nd{sub 3.5}Y{sub 0.5}Ce{sub 0.5}Gd{sub 0.5}). A grouped actinide separation has been successfully carried out by electrorefining on solid Al cathodes. At present the recovery of the actinides from the alloy formed with Al upon electrodeposition is under investigation, because an efficient P-T cycle requires multiple re-fabrication and re-irradiation. (authors)

  16. A Disposition for Benevolence

    ERIC Educational Resources Information Center

    O'Shea, Joseph

    2011-01-01

    This article presents the first half of an address at the 2011 Jon C. Dalton Institution on College Student Values. Drawing on personal reflections regarding his higher education experiences, the author argues that cultivating a robust disposition for benevolence requires a synthesis of intellectual engagement, critical self-reflection, and…

  17. Minority Report

    ERIC Educational Resources Information Center

    Honawar, Vaishali

    2006-01-01

    Stephanie Kwader is a white minority at the Bowie State University, a 5,500-student historically black university. Students like her belong to a small but growing group: minority students on the campuses of the nation's 105 historically black colleges and universities. HBCUs, as they are referred in the field, offer competitive academics with…

  18. Environmental research on actinide elements

    SciTech Connect

    Pinder, J.E. III; Alberts, J.J.; McLeod, K.W.; Schreckhise, R.G.

    1987-08-01

    The papers synthesize the results of research sponsored by DOE's Office of Health and Environmental Research on the behavior of transuranic and actinide elements in the environment. Separate abstracts have been prepared for the 21 individual papers. (ACR)

  19. Electrochemical decontamination system for actinide processing gloveboxes

    SciTech Connect

    Wedman, D.E.; Lugo, J.L.; Ford, D.K.; Nelson, T.O.; Trujillo, V.L.; Martinez, H.E.

    1998-03-01

    An electrolytic decontamination technology has been developed and successfully demonstrated at Los Alamos National Laboratory (LANL) for the decontamination of actinide processing gloveboxes. The technique decontaminates the interior surfaces of stainless steel gloveboxes utilizing a process similar to electropolishing. The decontamination device is compact and transportable allowing it to be placed entirely within the glovebox line. In this way, decontamination does not require the operator to wear any additional personal protective equipment and there is no need for additional air handling or containment systems. Decontamination prior to glovebox decommissioning reduces the potential for worker exposure and environmental releases during the decommissioning, transport, and size reduction procedures which follow. The goal of this effort is to reduce contamination levels of alpha emitting nuclides for a resultant reduction in waste level category from High Level Transuranic (TRU) to low Specific Activity (LSA, less than or equal 100 nCi/g). This reduction in category results in a 95% reduction in disposal and disposition costs for the decontaminated gloveboxes. The resulting contamination levels following decontamination by this method are generally five orders of magnitude below the LSA specification. Additionally, the sodium sulfate based electrolyte utilized in the process is fully recyclable which results in the minimum of secondary waste. The process bas been implemented on seven gloveboxes within LANL`s Plutonium Facility at Technical Area 55. Of these gloveboxes, two have been discarded as low level waste items and the remaining five have been reused.

  20. Actinide Targets for Neutron Cross Section Measurements (C)

    SciTech Connect

    J. D. Baker; C. A. McGrath

    2006-04-01

    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 (n,g) and (n,f) cross sections. A program of measurements under AFCI has begun to correct this. One of the initial hurdles has been to produce well-characterized, highly isotopically enriched, and chemically pure actinide targets on thin backings. Using a combination of resurrected techniques and new developments, we have made a series of targets including highly enriched 240Pu, and 242Pu. Thus far, we have electrodeposited these actinide targets. In the future, we plan to study reductive distillation to achieve homogeneous, adherent targets on thin metal foils and polymer backings. As we move forward, separated isotopes become scarcer, and safety concerns become greater. The chemical purification and electodeposition techniques will be described.

  1. Disposition of intravenous radioactive acyclovir

    SciTech Connect

    de Miranda, P.; Good, S.S.; Laskin, O.L.; Krasny, H.C.; Connor, J.D.; Lietman, P.S.

    1981-11-01

    The kinetic and metabolic disposition of (8-14C)acyclovir (ACV) was investigated in five subjects with advanced malignancy. The drug was administered by 1-hr intravenous infusion at doses of 0.5 and 2.5 mg/kg. Plasma and blood radioactivity-time, and plasma concentration-time data were defined by a two-compartment open kinetic model. There was nearly equivalent distribution of radioactivity in blood and plasma. The overall mean plasma half-life and total body clearance +/- SD of ACV were 2.1 +/- 0.5 hr and 297 +/- 53 ml/min/1.73 m2. Binding of ACV to plasma proteins was 15.4 +/- 4.4%. Most of the radioactive dose excreted was recovered in the urine (71% to 99%) with less than 2% excretion in the feces and only trace amounts in the expired Co2. Analyses by reverse-phase high-performance liquid chromatography indicated that 9-(carboxymethoxymethyl)guanine was the only significant urinary metabolite of ACV, accounting for 8.5% to 14.1% of the dose. A minor metabolite (less than 0.2% of dose) had the retention time of 8-hydroxy-9-((2-hydroxyethoxy)methyl)guanine. Unchanged urinary ACV ranged from 62% to 91% of the dose. There was no indication of ACV cleavage to guanine. Renal clearance of ACV was approximately three times the corresponding creatinine clearances.

  2. Behavior of actinides in the Integral Fast Reactor fuel cycle

    SciTech Connect

    Courtney, J.C.; Lineberry, M.J.

    1994-06-01

    The Integral Fast Reactor (IFR) under development by Argonne National Laboratory uses metallic fuels instead of ceramics. This allows electrorefining of spent fuels and presents opportunities for recycling minor actinide elements. Four minor actinides ({sup 237}Np, {sup 240}Pu, {sup 241}Am, and {sup 243}Am) determine the waste storage requirements of spent fuel from all types of fission reactors. These nuclides behave the same as uranium and other plutonium isotopes in electrorefining, so they can be recycled back to the reactor without elaborate chemical processing. An experiment has been designed to demonstrate the effectiveness of the high-energy neutron spectra of the IFR in consuming these four nuclides and plutonium. Eighteen sets of seven actinide and five light metal targets have been selected for ten day exposure in the Experimental Breeder Reactor-2 which serves as a prototype of the IFR. Post-irradiation analyses of the exposed targets by gamma, alpha, and mass spectroscopy are used to determine nuclear reaction-rates and neutron spectra. These experimental data increase the authors` confidence in their ability to predict reaction rates in candidate IFR designs using a variety of neutron transport and diffusion programs.

  3. Crystalline matrices for immobilization of actinides: Corrosion resistance in water

    NASA Astrophysics Data System (ADS)

    Yudintsev, S. V.; Aleksandrova, E. V.; Livshits, T. S.; Mal'kovskii, V. I.; Bychkova, Ya. V.; Tagirov, B. R.

    2014-10-01

    The rate of leaching of actinide-simulating rare-earth elements from two types of crystalline matrices consisting of titanate and titanozirconate phases was examined. The experiments were carried out at 95°C in distilled water. The rates of REE leaching from the samples were below 10-3 g/m2 day, which satisfied the requirements for the characteristics of matrices for immobilization of actinides. After passing the treated solutions through filters of 450 to 25 nm pore sizes, the REE content was changed slightly or not at all. This fact points to the minor role or to the absence of the colloidal form of REE in the solutions after the experiments.

  4. Kinetics of actinide complexation reactions

    SciTech Connect

    Nash, K.L.; Sullivan, J.C.

    1997-09-01

    Though the literature records extensive compilations of the thermodynamics of actinide complexation reactions, the kinetics of complex formation and dissociation reactions of actinide ions in aqueous solutions have not been extensively investigated. In light of the central role played by such reactions in actinide process and environmental chemistry, this situation is somewhat surprising. The authors report herein a summary of what is known about actinide complexation kinetics. The systems include actinide ions in the four principal oxidation states (III, IV, V, and VI) and complex formation and dissociation rates with both simple and complex ligands. Most of the work reported was conducted in acidic media, but a few address reactions in neutral and alkaline solutions. Complex formation reactions tend in general to be rapid, accessible only to rapid-scan and equilibrium perturbation techniques. Complex dissociation reactions exhibit a wider range of rates and are generally more accessible using standard analytical methods. Literature results are described and correlated with the known properties of the individual ions.

  5. Actinides and Life's Origins

    NASA Astrophysics Data System (ADS)

    Adam, Zachary

    2007-12-01

    There are growing indications that life began in a radioactive beach environment. A geologic framework for the origin or support of life in a Hadean heavy mineral placer beach has been developed, based on the unique chemical properties of the lower-electronic actinides, which act as nuclear fissile and fertile fuels, radiolytic energy sources, oligomer catalysts, and coordinating ions (along with mineralogically associated lanthanides) for prototypical prebiotic homonuclear and dinuclear metalloenzymes. A four-factor nuclear reactor model was constructed to estimate how much uranium would have been required to initiate a sustainable fission reaction within a placer beach sand 4.3 billion years ago. It was calculated that about 1-8 weight percent of the sand would have to have been uraninite, depending on the weight percent, uranium enrichment, and quantity of neutron poisons present within the remaining placer minerals. Radiolysis experiments were conducted with various solvents with the use of uranium- and thorium-rich minerals (metatorbernite and monazite, respectively) as proxies for radioactive beach sand in contact with different carbon, hydrogen, oxygen, and nitrogen reactants. Radiation bombardment ranged in duration of exposure from 3 weeks to 6 months. Low levels of acetonitrile (estimated to be on the order of parts per billion in concentration) were conclusively identified in 2 setups and tentatively indicated in a 3rd by gas chromatography/mass spectrometry. These low levels have been interpreted within the context of a Hadean placer beach prebiotic framework to demonstrate the promise of investigating natural nuclear reactors as power production sites that might have assisted the origins of life on young rocky planets with a sufficiently differentiated crust/mantle structure. Future investigations are recommended to better quantify the complex relationships between energy release, radioactive grain size, fissionability, reactant phase, phosphorus

  6. Actinides and Life's Origins.

    PubMed

    Adam, Zachary

    2007-12-01

    There are growing indications that life began in a radioactive beach environment. A geologic framework for the origin or support of life in a Hadean heavy mineral placer beach has been developed, based on the unique chemical properties of the lower-electronic actinides, which act as nuclear fissile and fertile fuels, radiolytic energy sources, oligomer catalysts, and coordinating ions (along with mineralogically associated lanthanides) for prototypical prebiotic homonuclear and dinuclear metalloenzymes. A four-factor nuclear reactor model was constructed to estimate how much uranium would have been required to initiate a sustainable fission reaction within a placer beach sand 4.3 billion years ago. It was calculated that about 1-8 weight percent of the sand would have to have been uraninite, depending on the weight percent, uranium enrichment, and quantity of neutron poisons present within the remaining placer minerals. Radiolysis experiments were conducted with various solvents with the use of uraniumand thorium-rich minerals (metatorbernite and monazite, respectively) as proxies for radioactive beach sand in contact with different carbon, hydrogen, oxygen, and nitrogen reactants. Radiation bombardment ranged in duration of exposure from 3 weeks to 6 months. Low levels of acetonitrile (estimated to be on the order of parts per billion in concentration) were conclusively identified in 2 setups and tentatively indicated in a 3(rd) by gas chromatography/mass spectrometry. These low levels have been interpreted within the context of a Hadean placer beach prebiotic framework to demonstrate the promise of investigating natural nuclear reactors as power production sites that might have assisted the origins of life on young rocky planets with a sufficiently differentiated crust/mantle structure. Future investigations are recommended to better quantify the complex relationships between energy release, radioactive grain size, fissionability, reactant phase, phosphorus

  7. Chemical aspects of actinides in the geosphere: towards a rational nuclear materials management

    SciTech Connect

    Allen, P; Sylwester, E

    2001-02-09

    A complete understanding of actinide interactions in the geosphere is paramount for developing a rational Nuclear and Environmental Materials Management Policy. One of the key challenges towards understanding the fate and transport of actinides is determining their speciation (i.e., oxidation state and structure). Since an element's speciation directly dictates physical properties such as toxicity and solubility, this information is critical for evaluating and controlling the evolution of an actinide element through the environment. Specific areas within nuclear and environmental management programs where speciation is important are (1) waste processing and separations; (2) wasteform materials for long-term disposition; and (3) aqueous geochemistry. The goal of this project was to develop Actinide X-ray Absorption Spectroscopy ( U S ) as a core capability at LLNL and integrate it with existing facilities, providing a multi-technique approach to actinide speciation. XAS is an element-specific structural probe which determines the oxidation state and structure for most atoms. XAS can be more incisive than other spectroscopies because it originates from an atomic process and the information is always attainable, regardless of an element's speciation. Despite the utility, XAS is relatively complex due to the need for synchrotron radiation and significant expertise with data acquisition and analysis. The coupling of these technical hurdles with the safe handling of actinides at a general user synchrotron facility such as the Stanford Synchrotron Radiation Facility (SSRL) make such experiments even more difficult. As a result, XAS has been underutilized by programs that could benefit by its application. We achieved our project goals by implementing key state-of-the-art Actinide XAS instrumentation at SSRL (Ge detector and remote positioning equipment), and by determining the chemical speciation of actinides (Th, U, and Np) in aqueous solutions, wasteform cements, and

  8. Actinide cation-cation complexes

    SciTech Connect

    Stoyer, N.J.; Seaborg, G.T.

    1994-12-01

    The +5 oxidation state of U, Np, Pu, and Am is a linear dioxo cation (AnO{sub 2}{sup +}) with a formal charge of +1. These cations form complexes with a variety of other cations, including actinide cations. Other oxidation states of actinides do not form these cation-cation complexes with any cation other than AnO{sub 2}{sup +}; therefore, cation-cation complexes indicate something unique about AnO{sub 2}{sup +} cations compared to actinide cations in general. The first cation-cation complex, NpO{sub 2}{sup +}{center_dot}UO{sub 2}{sup 2+}, was reported by Sullivan, Hindman, and Zielen in 1961. Of the four actinides that form AnO{sub 2}{sup +} species, the cation-cation complexes of NpO{sub 2}{sup +} have been studied most extensively while the other actinides have not. The only PuO{sub 2}{sup +} cation-cation complexes that have been studied are with Fe{sup 3+} and Cr{sup 3+} and neither one has had its equilibrium constant measured. Actinides have small molar absorptivities and cation-cation complexes have small equilibrium constants; therefore, to overcome these obstacles a sensitive technique is required. Spectroscopic techniques are used most often to study cation-cation complexes. Laser-Induced Photacoustic Spectroscopy equilibrium constants for the complexes NpO{sub 2}{sup +}{center_dot}UO{sub 2}{sup 2+}, NpO{sub 2}{sup +}{center_dot}Th{sup 4+}, PuO{sub 2}{sup +}{center_dot}UO{sub 2}{sup 2+}, and PuO{sub 2}{sup +}{center_dot}Th{sup 4+} at an ionic strength of 6 M using LIPAS are 2.4 {plus_minus} 0.2, 1.8 {plus_minus} 0.9, 2.2 {plus_minus} 1.5, and {approx}0.8 M{sup {minus}1}.

  9. Minority scholarships

    NASA Astrophysics Data System (ADS)

    The American Geological Institute sponsors undergraduate and graduate geoscience scholarships for members of ethnic minority groups. U.S. citizens who are majoring in geology, geophysics, geochemistry, hydrology, meteorology, oceanography, planetary geology, or Earth science education, and who are Black, Hispanic or Native American are eligible. Undergraduate awards can be as large as $10,000 a year; graduate awards, $4000 a year. Application deadline is February 1, 1990. Contact AGI Minority Participation Program Scholarships, American Geological Institute, 4220 King Street, Alexandria, VA 22302-1507; tel. 703-379-2480.

  10. Actinide Thermodynamics at Elevated Temperatures

    SciTech Connect

    Friese, Judah I.; Rao, Linfeng; Xia, Yuanxian; Bachelor, Paula P.; Tian, Guoxin

    2007-11-16

    The postclosure chemical environment in the proposed Yucca Mountain repository is expected to experience elevated temperatures. Predicting migration of actinides is possible if sufficient, reliable thermodynamic data on hydrolysis and complexation are available for these temperatures. Data are scarce and scattered for 25 degrees C, and nonexistent for elevated temperatures. This collaborative project between LBNL and PNNL collects thermodynamic data at elevated temperatures on actinide complexes with inorganic ligands that may be present in Yucca Mountain. The ligands include hydroxide, fluoride, sulfate, phosphate and carbonate. Thermodynamic parameters of complexation, including stability constants, enthalpy, entropy and heat capacity of complexation, are measured with a variety of techniques including solvent extraction, potentiometry, spectrophotometry and calorimetry

  11. Revisiting Professional Dispositions: Research Redux

    ERIC Educational Resources Information Center

    Bush, Gail; Jones, Jami L.

    2011-01-01

    As the authors progressed through their research agenda last year, they contributed an article to "School Library Monthly" entitled "Forecasting Professional Dispositions of School Librarians" (January 2011, 54-56) wherein they described a Delphi study they conducted in the fall of 2009 that identified professional dispositions based on responses…

  12. Separations of actinides, lanthanides and other metals

    DOEpatents

    Smith, Barbara F.; Jarvinen, Gordon D.; Ensor, Dale D.

    1995-01-01

    An organic extracting solution comprised of a bis(acylpyrazolone or a substituted bis(acylpyrazolone) and an extraction method useful for separating certain elements of the actinide series of the periodic table having a valence of four from one other, and also from one or more of the substances in a group consisting of hexavalent actinides, trivalent actinides, trivalent lanthanides, trivalent iron, trivalent aluminum, divalent metals, and monovalent metals and also from one or more of the substances in a group consisting of hexavalent actinides, trivalent actinides, trivalent lanthanides, trivalent iron, trivalent aluminum, divalent metals, and monovalent metals and also useful for separating hexavalent actinides from one or more of the substances in a group consisting of trivalent actinides, trivalent lanthanides, trivalent iron, trivalent aluminum, divalent metals, and monovalent metals.

  13. SAMPLE RESULTS FROM THE INTEGRATED SALT DISPOSITION PROGRAM MACROBATCH 5 TANK 21H QUALIFICATION MST, ESS AND PODD SAMPLES

    SciTech Connect

    Peters, T.; Fink, S.

    2012-04-24

    Savannah River National Laboratory (SRNL) performed experiments on qualification material for use in the Integrated Salt Disposition Program (ISDP) Batch 5 processing. This qualification material was a composite created from recent samples from Tank 21H and archived samples from Tank 49H to match the projected blend from these two tanks. Additionally, samples of the composite were used in the Actinide Removal Process (ARP) and extraction-scrub-strip (ESS) tests. ARP and ESS test results met expectations. A sample from Tank 21H was also analyzed for the Performance Objectives Demonstration Document (PODD) requirements. SRNL was able to meet all of the requirements, including the desired detection limits for all the PODD analytes. This report details the results of the Actinide Removal Process (ARP), Extraction-Scrub-Strip (ESS) and Performance Objectives Demonstration Document (PODD) samples of Macrobatch (Salt Batch) 5 of the Integrated Salt Disposition Program (ISDP).

  14. Disposition of citral in male Fischer rats

    SciTech Connect

    Diliberto, J.J.; Usha, G.; Birnbaum, L.S.

    1988-09-01

    The disposition of citral, an essential oil occurring in many foods and fragrances, was studied in male Fischer rats after iv, po, and dermal treatments. The pattern of distribution and elimination was the same after iv or oral exposure. Urine was the major route of elimination of citral-derived radioactivity, followed by feces, /sup 14/CO/sub 2/, and expired volatiles. However, after dermal exposure, relatively less of the material was eliminated in the urine and more in the feces, suggesting a role for first-pass metabolism through the skin. Citral was almost completely absorbed orally; due to its extreme volatility, much of an applied dermal dose was lost. The citral remaining on the skin was fairly well absorbed. No effect of oral dose, from 5 to 500 mg/kg, was detected on disposition. Although the feces was a minor route of excretion, approximately 25% of the administered dose was eliminated via the bile within 4 hr of an iv dose. The metabolism of citral was both rapid and extensive. Within 5 min of an iv dose, no unmetabolized citral could be detected in the blood. Repeated exposure to citral resulted in an increase in biliary elimination, without any significant change in the pattern of urinary, fecal, or exhaled excretion. This suggests that citral may induce at least one pathway of its own metabolism. The rapid metabolism and excretion of this compound suggest that significant bioaccumulation of citral would not occur.

  15. 17 CFR 10.91 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Summary disposition. 10.91... Disposition Without Full Hearing § 10.91 Summary disposition. (a) Filing of motions, answers. Any party who... decision as a matter of law may move for a summary disposition in his favor of all or any part of...

  16. 12 CFR 1081.212 - Dispositive motions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 8 2013-01-01 2013-01-01 false Dispositive motions. 1081.212 Section 1081.212... Initiation of Proceedings and Prehearing Rules § 1081.212 Dispositive motions. (a) Dispositive motions. This section governs the filing of motions to dismiss and motions for summary disposition. The filing of...

  17. "Computational Modeling of Actinide Complexes"

    SciTech Connect

    Balasubramanian, K

    2007-03-07

    We will present our recent studies on computational actinide chemistry of complexes which are not only interesting from the standpoint of actinide coordination chemistry but also of relevance to environmental management of high-level nuclear wastes. We will be discussing our recent collaborative efforts with Professor Heino Nitsche of LBNL whose research group has been actively carrying out experimental studies on these species. Computations of actinide complexes are also quintessential to our understanding of the complexes found in geochemical, biochemical environments and actinide chemistry relevant to advanced nuclear systems. In particular we have been studying uranyl, plutonyl, and Cm(III) complexes are in aqueous solution. These studies are made with a variety of relativistic methods such as coupled cluster methods, DFT, and complete active space multi-configuration self-consistent-field (CASSCF) followed by large-scale CI computations and relativistic CI (RCI) computations up to 60 million configurations. Our computational studies on actinide complexes were motivated by ongoing EXAFS studies of speciated complexes in geo and biochemical environments carried out by Prof Heino Nitsche's group at Berkeley, Dr. David Clark at Los Alamos and Dr. Gibson's work on small actinide molecules at ORNL. The hydrolysis reactions of urnayl, neputyl and plutonyl complexes have received considerable attention due to their geochemical and biochemical importance but the results of free energies in solution and the mechanism of deprotonation have been topic of considerable uncertainty. We have computed deprotonating and migration of one water molecule from the first solvation shell to the second shell in UO{sub 2}(H{sub 2}O){sub 5}{sup 2+}, UO{sub 2}(H{sub 2}O){sub 5}{sup 2+}NpO{sub 2}(H{sub 2}O){sub 6}{sup +}, and PuO{sub 2}(H{sub 2}O){sub 5}{sup 2+} complexes. Our computed Gibbs free energy(7.27 kcal/m) in solution for the first time agrees with the experiment (7.1 kcal

  18. DEVELOPMENT OF GLASS AND CRYSTALLINE CERAMIC FORMS FOR DISPOSITION OF EXCESS PLUTONIUM

    SciTech Connect

    Marra, James; Cozzi, A; Crawford, C.; Herman, C.; Marra, John; Peeler, D.

    2009-09-10

    In the aftermath of the Cold War, the United States Department of Energy (DOE) has identified up to 50 metric tons of excess plutonium that needs to be dispositioned. The bulk of the material is slated to be blended with uranium and fabricated into a Mixed Oxide (MOX) fuel for subsequent burning in commercial nuclear reactors. Excess plutonium-containing impurity materials making it unsuitable for fabrication into MOX fuel will need to be dispositioned via other means. Glass and crystalline ceramics have been developed and studied as candidate forms to immobilize these impure plutonium feeds. A titanate-based ceramic was identified as an excellent actinide material host. This composition was based on Synroc compositions previously developed for nuclear waste immobilization. These titanate ceramics were found to be able to accommodate extremely high quantities of fissile material and exhibit excellent aqueous durability. A lanthanide borosilicate (LaBS) glass was developed to accommodate high concentrations of plutonium and to be very tolerant of impurities yet still maintain good aqueous durability. Recent testing of alkali borosilicate compositions showed promise of using these compositions to disposition lower concentrations of plutonium using existing high level waste vitrification processes. The developed waste forms all appear to be suitable for Pu disposition. Depending on the actual types and concentrations of the Pu residue streams slated for disposition, each waste form offers unique advantages.

  19. Future nuclear fuel cycles: Prospect and challenges for actinide recycling

    NASA Astrophysics Data System (ADS)

    Warin, Dominique

    2010-03-01

    The global energy context pleads in favour of a sustainable development of nuclear energy since the demand for energy will likely increase, whereas resources will tend to get scarcer and the prospect of global warming will drive down the consumption of fossil fuel. In this context, nuclear power has the worldwide potential to curtail the dependence on fossil fuels and thereby to reduce the amount of greenhouse gas emissions while promoting energy independence. How we deal with nuclear radioactive waste is crucial in this context. In France, the public's concern regarding the long-term waste management made the French Governments to prepare and pass the 1991 and 2006 Acts, requesting in particular the study of applicable solutions for still minimizing the quantity and the hazardousness of final waste. This necessitates High Active Long Life element (such as the Minor Actinides MA) recycling, since the results of fuel cycle R&D could significantly change the challenges for the storage of nuclear waste. HALL recycling can reduce the heat load and the half-life of most of the waste to be buried to a couple of hundred years, overcoming the concerns of the public related to the long-life of the waste and thus aiding the "burying approach" in securing a "broadly agreed political consensus" of waste disposal in a geological repository. This paper presents an overview of the recent R and D results obtained at the CEA Atalante facility on innovative actinide partitioning hydrometallurgical processes. For americium and curium partitioning, these results concern improvements and possible simplifications of the Diamex-Sanex process, whose technical feasibility was already demonstrated in 2005. Results on the first tests of the Ganex process (grouped actinide separation for homogeneous recycling) are also discussed. In the coming years, next steps will involve both better in-depth understanding of the basis of these actinide partitioning processes and, for the new promising

  20. Process for recovering actinide values

    DOEpatents

    Horwitz, E. Philip; Mason, George W.

    1980-01-01

    A process for rendering actinide values recoverable from sodium carbonate scrub waste solutions containing these and other values along with organic compounds resulting from the radiolytic and hydrolytic degradation of neutral organophosphorous extractants such as tri-n butyl phosphate (TBP) and dihexyl-N,N-diethyl carbamylmethylene phosphonate (DHDECAMP) which have been used in the reprocessing of irradiated nuclear reactor fuels. The scrub waste solution is preferably made acidic with mineral acid, to form a feed solution which is then contacted with a water-immiscible, highly polar organic extractant which selectively extracts the degradation products from the feed solution. The feed solution can then be processed to recover the actinides for storage or recycled back into the high-level waste process stream. The extractant is recycled after stripping the degradation products with a neutral sodium carbonate solution.

  1. Actinide abundances in ordinary chondrites

    NASA Technical Reports Server (NTRS)

    Hagee, B.; Bernatowicz, T. J.; Podosek, F. A.; Johnson, M. L.; Burnett, D. S.

    1990-01-01

    Measurements of actinide and light REE (LREE) abundances and of phosphate abundances in equilibrated ordinary chondrites were obtained and were used to define the Pu abundance in the solar system and to determine the degree of variation of actinide and LREE abundances. The results were also used to compare directly the Pu/U ratio with the earlier obtained ratio determined indirectly, as (Pu/Nd)x(Nd/U), assuming that Pu behaves chemically as a LREE. The data, combined with high-accuracy isotope-dilution data from the literature, show that the degree of gram-scale variability of the Th, U, and LREE abundances for equilibrated ordinary chondrites is a factor of 2-3 for absolute abundances and up to 50 percent for relative abundances. The observed variations are interpreted as reflecting the differences in the compositions and/or proportions of solar nebula components accreted to ordinary chondrite parent bodies.

  2. Actinide chemistry in ionic liquids.

    PubMed

    Takao, Koichiro; Bell, Thomas James; Ikeda, Yasuhisa

    2013-04-01

    This Forum Article provides an overview of the reported studies on the actinide chemistry in ionic liquids (ILs) with a particular focus on several fundamental chemical aspects: (i) complex formation, (ii) electrochemistry, and (iii) extraction behavior. The majority of investigations have been dedicated to uranium, especially for the 6+ oxidation state (UO2(2+)), because the chemistry of uranium in ordinary solvents has been well investigated and uranium is the most abundant element in the actual nuclear fuel cycles. Other actinides such as thorium, neptunium, plutonium, americium, and curiumm, although less studied, are also of importance in fully understanding the nuclear fuel engineering process and the safe geological disposal of radioactive wastes. PMID:22873132

  3. Actinide Studies with Ultracold Neutrons

    NASA Astrophysics Data System (ADS)

    Broussard, Leah

    2014-03-01

    Understanding the effects of sputtering due to nuclear fission is crucial to the nuclear industry and has wide-reaching applications, including nuclear energy, space science, and national defense. A new program at the Los Alamos Neutron Science Center uses ultracold neutrons (UCN) to induce fission in actinides such as uranium and plutonium. UCN are an ideal tool for finely controlling induced fission as a function of depth in an actinide sample. The mechanism for fission-induced surface damage is not well understood, especially regarding the effect of a surface oxide layer. We will discuss our experimental strategy for studies of UCN-induced fission and the ejected material, and present preliminary data from enriched and depleted uranium. We gratefully acknowledge the support of the G. T. Seaborg Institute for Transactinium Science and the U.S. Department of Energy through the LANL/LDRD Program for this work.

  4. FS65 Disposition Option Report

    SciTech Connect

    Wenz, Tracy R.

    2015-09-25

    This report outlines the options for dispositioning the MOX fuel stored in FS65 containers at LANL. Additional discussion regarding the support equipment for loading and unloading the FS65 transport containers is included at the end of the report.

  5. Actinide Waste Forms and Radiation Effects

    NASA Astrophysics Data System (ADS)

    Ewing, R. C.; Weber, W. J.

    Over the past few decades, many studies of actinides in glasses and ceramics have been conducted that have contributed substantially to the increased understanding of actinide incorporation in solids and radiation effects due to actinide decay. These studies have included fundamental research on actinides in solids and applied research and development related to the immobilization of the high level wastes (HLW) from commercial nuclear power plants and processing of nuclear weapons materials, environmental restoration in the nuclear weapons complex, and the immobilization of weapons-grade plutonium as a result of disarmament activities. Thus, the immobilization of actinides has become a pressing issue for the twenty-first century (Ewing, 1999), and plutonium immobilization, in particular, has received considerable attention in the USA (Muller et al., 2002; Muller and Weber, 2001). The investigation of actinides and

  6. Actinide recovery techniques utilizing electromechanical processes

    SciTech Connect

    Westphal, B.R.; Benedict, R.W.

    1994-01-01

    Under certain conditions, the separation of actinides using electromechanical techniques may be an effective means of residue processing. The separation of granular mixtures of actinides and other materials discussed in this report is based on appreciable differences in the magnetic and electrical properties of the actinide elements. In addition, the high density of actinides, particularly uranium and plutonium, may render a simultaneous separation based on mutually complementary parameters. Both high intensity magnetic separation and electrostatic separation have been investigated for the concentration of an actinide waste stream. Waste stream constituents include an actinide metal alloy and broken quartz shards. The investigation of these techniques is in support of the Integral Fast Reactor (IFR) concept currently being developed at Argonne National Laboratory under the auspices of the Department of Energy.

  7. Aquatic chemistry of actinides: Is a thermodynamic approach appropriate to describe natural dynamic systems?

    NASA Astrophysics Data System (ADS)

    Kim, J. I.

    2000-07-01

    The worldwide civilian use of nuclear energy generates yearly about 11,000 tons of spent-fuel from 433 nuclear power plants (NPP) in operation for the moment with an installed capacity of approximately 350 GWe (36 NPP are being under construction). This contributes to the world electricity production about 17%. The hitherto discharged spent-fuel is estimated to be around 220,000 tons, which contain about 1,400 tons of plutonium and a considerable amount of minor actinides and fission products. The total quantity of long-lived radioactive elements mostly actinides, increases steadily. The foreseeable solution for their isolation from the biosphere is a geological disposal with safe confinement. The long-term safety assessment of such containment entails well-founded knowledge on the aquatic chemistry of actinides, most of all, their thermodynamic properties in the geochemical environment.

  8. Energy-Dependent Fission Q Values Generalized for All Actinides

    SciTech Connect

    Vogt, R

    2008-09-25

    We generalize Madland's parameterization of the energy release in fission to obtain the dependence of the fission Q values on incident neutron energy, E{sub n}, for all major and minor actinides. These Q(E{sub n}) parameterizations are included in the ENDL2008 release. This paper describes calculations of energy-dependent fission Q values based on parameterizations of the prompt energy release in fission [1], developed by Madland [1] to describe the prompt energy release in neutron-induced fission of {sup 235}U, {sup 238}U, and {sup 239}Pu. The energy release is then related to the energy deposited during fission so that experimentally measurable quantities can be used to obtain the Q values. A discussion of these specific parameterizations and their implementation in the processing code for Monte Carlo neutron transport, MCFGEN, [2] is described in Ref. [3]. We extend this model to describe Q(E) for all actinides, major and minor, in the Evaluated Nuclear Data Library (ENDL) 2008 release, ENDL2008.

  9. Minority Fellowships

    NASA Astrophysics Data System (ADS)

    Carlowicz, Michael

    In an effort to increase the number of ethnic minorities on the faculties of American colleges and universities, the Ford Foundation is offering fellowships to members of six groups who have been severely underrepresented in academia.In a program administered by the National Research Council (NRC), the Ford Foundation is offering 50 three-year predoctoral fellowships ($14,000 per year, plus a $6000 annual institutional grant) and 25 one-year dissertation fellowships ($18,000 for one year) to Native American Indians, Alaskan natives (Eskimos, Aleuts), Black/African Americans, Mexican Americans/Chicanos, Native Pacific Islanders (Polynesians and Micronesians), and Puerto Ricans. Fellowships will be awarded in the behavioral and social sciences, humanities, engineering, mathematics, physical sciences, life sciences, or interdisciplinary programs composed of two or more of those disciplines. The predoctoral fellowships are intended for beginning graduate students; the dissertation fellowships are designed to provide support for students in their final year.

  10. Density functional theory investigations of the trivalent lanthanide and actinide extraction complexes with diglycolamides.

    PubMed

    Wang, Cong-Zhi; Lan, Jian-Hui; Wu, Qun-Yan; Zhao, Yu-Liang; Wang, Xiang-Ke; Chai, Zhi-Fang; Shi, Wei-Qun

    2014-06-21

    At present, designing novel ligands for efficient actinide extraction in spent nuclear fuel reprocessing is extremely challenging due to the complicated chemical behaviors of actinides, the similar chemical properties of minor actinides (MA) and lanthanides, and the vulnerability of organic ligands in acidic radioactive solutions. In this work, a quantum chemical study on Am(III), Cm(III) and Eu(III) complexes with N,N,N',N'-tetraoctyl diglycolamide (TODGA) and N,N'-dimethyl-N,N'-diheptyl-3-oxapentanediamide (DMDHOPDA) has been carried out to explore the extraction behaviors of trivalent actinides (An) and lanthanides (Ln) with diglycolamides from acidic media. It has been found that in the 1 : 1 (ligand : metal) and 2 : 1 stoichiometric complexes, the carbonyl oxygen atoms have stronger coordination ability than the ether oxygen atoms, and the interactions between metal cations and organic ligands are substantially ionic. The neutral ML(NO3)3 (M = Am, Cm, Eu) complexes seem to be the most favorable species in the extraction process, and the predicted relative selectivities are in agreement with experimental results, i.e., the diglycolamide ligands have slightly higher selectivity for Am(III) over Eu(III). Such a thermodynamical priority is probably caused by the higher stabilities of Eu(III) hydration species and Eu(III)-L complexes in aqueous solution compared to their analogues. In addition, our thermodynamic analysis from water to organic medium confirms that DMDHOPDA has higher extraction ability for the trivalent actinides and lanthanides than TODGA, which may be due to the steric hindrance of the bulky alkyl groups of TODGA ligands. This work might provide an insight into understanding the origin of the actinide selectivity and a theoretical basis for designing highly efficient extractants for actinide separation. PMID:24769618

  11. Use of soft heterocyclic N-donor ligands to separate actinides and lanthanides.

    PubMed

    Hudson, Michael J; Harwood, Laurence M; Laventine, Dominic M; Lewis, Frank W

    2013-04-01

    The removal of the most long-lived radiotoxic elements from used nuclear fuel, minor actinides, is foreseen as an essential step toward increasing the public acceptance of nuclear energy as a key component of a low-carbon energy future. Once removed from the remaining used fuel, these elements can be used as fuel in their own right in fast reactors or converted into shorter-lived or stable elements by transmutation prior to geological disposal. The SANEX process is proposed to carry out this selective separation by solvent extraction. Recent efforts to develop reagents capable of separating the radioactive minor actinides from lanthanides as part of a future strategy for the management and reprocessing of used nuclear fuel are reviewed. The current strategies for the reprocessing of PUREX raffinate are summarized, and some guiding principles for the design of actinide-selective reagents are defined. The development and testing of different classes of solvent extraction reagent are then summarized, covering some of the earliest ligand designs right through to the current reagents of choice, bis(1,2,4-triazine) ligands. Finally, we summarize research aimed at developing a fundamental understanding of the underlying reasons for the excellent extraction capabilities and high actinide/lanthanide selectivities shown by this class of ligands and our recent efforts to immobilize these reagents onto solid phases. PMID:22867058

  12. Analysis of large soil samples for actinides

    DOEpatents

    Maxwell, III; Sherrod L.

    2009-03-24

    A method of analyzing relatively large soil samples for actinides by employing a separation process that includes cerium fluoride precipitation for removing the soil matrix and precipitates plutonium, americium, and curium with cerium and hydrofluoric acid followed by separating these actinides using chromatography cartridges.

  13. Prompt fission neutron spectra of actinides

    DOE PAGESBeta

    Capote, R.; Chen, Y. -J.; Hambsch, F. -J.; Kornilov, N. V.; Lestone, J. P.; Litaize, O.; Morillon, B.; Neudecker, D.; Oberstedt, S.; Ohsawa, T.; et al

    2016-01-06

    Here, the energy spectrum of prompt neutrons emitted in fission (PFNS) plays a very important role in nuclear science and technology. A Coordinated Research Project (CRP) "Evaluation of Prompt Fission Neutron Spectra of Actinides" was established by the IAEA Nuclear Data Section in 2009, with the major goal to produce new PFNS evaluations with uncertainties for actinide nuclei.

  14. Actinide abundances in ordinary chondrites

    USGS Publications Warehouse

    Hagee, B.; Bernatowicz, T.J.; Podosek, F.A.; Johnson, M.L.; Burnett, D.S.; Tatsumoto, M.

    1990-01-01

    Measurements of 244Pu fission Xe, U, Th, and light REE (LREE) abundances, along with modal petrographic determinations of phosphate abundances, were carried out on equilibrated ordinary chondrites in order to define better the solar system Pu abundance and to determine the degree of variation of actinide and LREE abundances. Our data permit comparison of the directly measured Pu/ U ratio with that determined indirectly as (Pu/Nd) ?? (Nd/U) assuming that Pu behaves chemically as a LREE. Except for Guaren??a, and perhaps H chondrites in general, Pu concentrations are similar to that determined previously for St. Se??verin, although less precise because of higher trapped Xe contents. Trapped 130Xe 136Xe ratios appear to vary from meteorite to meteorite, but, relative to AVCC, all are similar in the sense of having less of the interstellar heavy Xe found in carbonaceous chondrite acid residues. The Pu/U and Pu/Nd ratios are consistent with previous data for St. Se??verin, but both tend to be slightly higher than those inferred from previous data on Angra dos Reis. Although significant variations exist, the distribution of our Th/U ratios, along with other precise isotope dilution data for ordinary chondrites, is rather symmetric about the CI chondrite value; however, actinide/(LREE) ratios are systematically lower than the CI value. Variations in actinide or LREE absolute and relative abundances are interpreted as reflecting differences in the proportions and/or compositions of more primitive components (chondrules and CAI materials?) incorporated into different regions of the ordinary chondrite parent bodies. The observed variations of Th/U, Nd/U, or Ce/U suggest that measurements of Pu/U on any single equilibrated ordinary chondrite specimen, such as St. Se??verin, should statistically be within ??20-30% of the average solar system value, although it is also clear that anomalous samples exist. ?? 1990.

  15. Separation of actinides from lanthanides

    DOEpatents

    Smith, Barbara F.; Jarvinen, Gordon D.; Ryan, Robert R.

    1989-01-01

    An organic extracting solution and an extraction method useful for separating elements of the actinide series of the periodic table from elements of the lanthanide series, where both are in trivalent form. The extracting solution consists of a primary ligand and a secondary ligand, preferably in an organic solvent. The primary ligand is a substituted monothio-1,3-dicarbonyl, which includes a substituted 4-acyl-2-pyrazolin-5-thione, such as 4-benzoyl-2,4-dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT). The secondary ligand is a substituted phosphine oxide, such as trioctylphosphine oxide (TOPO).

  16. Separation of actinides from lanthanides

    DOEpatents

    Smith, B.F.; Jarvinen, G.D.; Ryan, R.R.

    1988-03-31

    An organic extracting solution and an extraction method useful for separating elements of the actinide series of the periodic table from elements of the lanthanide series, where both are in trivalent form is described. The extracting solution consists of a primary ligand and a secondary ligand, preferably in an organic solvent. The primary ligand is a substituted monothio-1,3-dicarbonyl, which includes a substituted 4-acyl-2-pyrazolin-5-thione, such as 4-benzoyl-2,4- dihydro-5-methyl-2-phenyl-3H-pyrazol-3-thione (BMPPT). The secondary ligand is a substituted phosphine oxide, such as trioctylphosphine oxide (TOPO).

  17. Exploring actinide materials through synchrotron radiation techniques.

    PubMed

    Shi, Wei-Qun; Yuan, Li-Yong; Wang, Cong-Zhi; Wang, Lin; Mei, Lei; Xiao, Cheng-Liang; Zhang, Li; Li, Zi-Jie; Zhao, Yu-Liang; Chai, Zhi-Fang

    2014-12-10

    Synchrotron radiation (SR) based techniques have been utilized with increasing frequency in the past decade to explore the brilliant and challenging sciences of actinide-based materials. This trend is partially driven by the basic needs for multi-scale actinide speciation and bonding information and also the realistic needs for nuclear energy research. In this review, recent research progresses on actinide related materials by means of various SR techniques were selectively highlighted and summarized, with the emphasis on X-ray absorption spectroscopy, X-ray diffraction and scattering spectroscopy, which are powerful tools to characterize actinide materials. In addition, advanced SR techniques for exploring future advanced nuclear fuel cycles dealing with actinides are illustrated as well. PMID:25169914

  18. Actinide ion sensor for pyroprocess monitoring

    DOEpatents

    Jue, Jan-fong; Li, Shelly X.

    2014-06-03

    An apparatus for real-time, in-situ monitoring of actinide ion concentrations which comprises a working electrode, a reference electrode, a container, a working electrolyte, a separator, a reference electrolyte, and a voltmeter. The container holds the working electrolyte. The voltmeter is electrically connected to the working electrode and the reference electrode and measures the voltage between those electrodes. The working electrode contacts the working electrolyte. The working electrolyte comprises an actinide ion of interest. The reference electrode contacts the reference electrolyte. The reference electrolyte is separated from the working electrolyte by the separator. The separator contacts both the working electrolyte and the reference electrolyte. The separator is ionically conductive to the actinide ion of interest. The reference electrolyte comprises a known concentration of the actinide ion of interest. The separator comprises a beta double prime alumina exchanged with the actinide ion of interest.

  19. Depleted uranium disposition study -- Supplement, Revision 1

    SciTech Connect

    Becker, G.W.

    1993-11-01

    The Department of Energy Office of Weapons and Materials Planning has requested a supplemental study to update the recent Depleted Uranium Disposition report. This supplemental study addresses new disposition alternatives and changes in status.

  20. 39 CFR 954.3 - Informal dispositions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., SUSPENSION, OR REVOCATION OF PERIODICALS MAIL PRIVILEGES § 954.3 Informal dispositions. These rules do not preclude the informal dispositions of Periodicals mailing privilege matters before or after institution...

  1. 39 CFR 954.3 - Informal dispositions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., SUSPENSION, OR REVOCATION OF PERIODICALS MAIL PRIVILEGES § 954.3 Informal dispositions. These rules do not preclude the informal dispositions of Periodicals mailing privilege matters before or after institution...

  2. 39 CFR 954.3 - Informal dispositions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., SUSPENSION, OR REVOCATION OF PERIODICALS MAIL PRIVILEGES § 954.3 Informal dispositions. These rules do not preclude the informal dispositions of Periodicals mailing privilege matters before or after institution...

  3. 39 CFR 954.3 - Informal dispositions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., SUSPENSION, OR REVOCATION OF PERIODICALS MAIL PRIVILEGES § 954.3 Informal dispositions. These rules do not preclude the informal dispositions of Periodicals mailing privilege matters before or after institution...

  4. 39 CFR 954.3 - Informal dispositions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., SUSPENSION, OR REVOCATION OF PERIODICALS MAIL PRIVILEGES § 954.3 Informal dispositions. These rules do not preclude the informal dispositions of Periodicals mailing privilege matters before or after institution...

  5. Rapid actinide-separation methods

    SciTech Connect

    Maxwell, S.L. III

    1997-12-31

    New high-speed actinide-separation methods have been developed by the Savannah River Site Central Laboratory that can be applied to nuclear materials process samples, waste solutions and environmental samples. As part of a reengineering effort to improve efficiencies and reduce operating costs, solvent extraction methods (TTA, Hexone, TBP and TIOA) used for over thirty years in the SRS Central Laboratory were replaced with new rapid extraction column methods able to handle a variety of difficult sample matrices and actinide levels. Significant costs savings were realized and costly mixed-waste controls were avoided by using applied vacuum and 50-100 micron particle-size resins from Eichrom Industries. TEVA Resin{reg_sign}, UTEVA Resin{reg_sign}, and TRU Resin{reg_sign} columns are used with flow rates of approximately two to three milliliters per minute to minimize sample turnaround times. Single-column, dual-column and sequential-cartridge methods for plutonium, uranium, neptunium, americium and curium were developed that enable rapid, cost-effective separations prior to alpha-particle counting, thermal ionization and inductively coupled plasma mass spectrometry, and laser phosphorescence measurements.

  6. 24 CFR 290.15 - Disposition plan.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... plan, the environmental reviews required by 24 CFR part 50. ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Disposition plan. 290.15 Section... MORTGAGES Disposition of Multifamily Projects § 290.15 Disposition plan. (a) In general. Before disposing...

  7. 24 CFR 290.15 - Disposition plan.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... plan, the environmental reviews required by 24 CFR part 50. ... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Disposition plan. 290.15 Section... MORTGAGES Disposition of Multifamily Projects § 290.15 Disposition plan. (a) In general. Before disposing...

  8. 24 CFR 290.15 - Disposition plan.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... plan, the environmental reviews required by 24 CFR part 50. ... 24 Housing and Urban Development 2 2014-04-01 2014-04-01 false Disposition plan. 290.15 Section... MORTGAGES Disposition of Multifamily Projects § 290.15 Disposition plan. (a) In general. Before disposing...

  9. 17 CFR 12.310 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Summary disposition. 12.310... REPARATIONS Rules Applicable to Formal Decisional Proceedings § 12.310 Summary disposition. (a) Filing of... proceeding may file a motion for summary disposition at any time before a determination is made by...

  10. 17 CFR 10.91 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Summary disposition. 10.91 Section 10.91 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION RULES OF PRACTICE Disposition Without Full Hearing § 10.91 Summary disposition. (a) Filing of motions, answers. Any party who believes that there is no genuine...

  11. 17 CFR 12.207 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Summary disposition. 12.207... REPARATIONS Rules Applicable to Summary Decisional Proceedings § 12.207 Summary disposition. (a) Filing of... proceeding may file a motion for summary disposition at any time until the parties have concluded...

  12. 19 CFR 147.42 - Disposition generally.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.42 Disposition generally. (a) Kinds of disposition. Any article entered for a fair under this part may be entered for consumption, for warehouse, or under any other provision of the Customs laws, or for another fair, or may...

  13. 19 CFR 147.42 - Disposition generally.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.42 Disposition generally. (a) Kinds of disposition. Any article entered for a fair under this part may be entered for consumption, for warehouse, or under any other provision of the Customs laws, or for another fair, or may...

  14. 19 CFR 147.42 - Disposition generally.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.42 Disposition generally. (a) Kinds of disposition. Any article entered for a fair under this part may be entered for consumption, for warehouse, or under any other provision of the Customs laws, or for another fair, or may...

  15. 19 CFR 147.42 - Disposition generally.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.42 Disposition generally. (a) Kinds of disposition. Any article entered for a fair under this part may be entered for consumption, for warehouse, or under any other provision of the Customs laws, or for another fair, or may...

  16. 12 CFR 747.29 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Summary disposition. 747.29 Section 747.29... of Practice and Procedure § 747.29 Summary disposition. (a) In general. The administrative law judge shall recommend that the NCUA Board issue a final order granting a motion for summary disposition if...

  17. 12 CFR 509.29 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Summary disposition. 509.29 Section 509.29... PROCEDURE IN ADJUDICATORY PROCEEDINGS Uniform Rules of Practice and Procedure § 509.29 Summary disposition... granting a motion for summary disposition if the undisputed pleaded facts, admissions,...

  18. 12 CFR 1780.31 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Summary disposition. 1780.31 Section 1780.31... Summary disposition. (a) In general. The presiding officer shall recommend that the Director issue a final order granting a motion for summary disposition if the undisputed pleaded facts, admissions,...

  19. 12 CFR 747.29 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Summary disposition. 747.29 Section 747.29... of Practice and Procedure § 747.29 Summary disposition. (a) In general. The administrative law judge shall recommend that the NCUA Board issue a final order granting a motion for summary disposition if...

  20. 12 CFR 263.29 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Summary disposition. 263.29 Section 263.29... RULES OF PRACTICE FOR HEARINGS Uniform Rules of Practice and Procedure § 263.29 Summary disposition. (a... a motion for summary disposition if the undisputed pleaded facts, admissions,...

  1. 12 CFR 308.29 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Summary disposition. 308.29 Section 308.29... PRACTICE AND PROCEDURE Uniform Rules of Practice and Procedure § 308.29 Summary disposition. (a) In general... a motion for summary disposition if the undisputed pleaded facts, admissions,...

  2. 12 CFR 509.29 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 5 2011-01-01 2011-01-01 false Summary disposition. 509.29 Section 509.29... PROCEDURE IN ADJUDICATORY PROCEEDINGS Uniform Rules of Practice and Procedure § 509.29 Summary disposition... granting a motion for summary disposition if the undisputed pleaded facts, admissions,...

  3. 10 CFR 2.1205 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Summary disposition. 2.1205 Section 2.1205 Energy NUCLEAR... Hearing Procedures for NRC Adjudications § 2.1205 Summary disposition. (a) Unless the presiding officer or the Commission directs otherwise, motions for summary disposition may be submitted to the...

  4. 12 CFR 1780.31 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 7 2011-01-01 2011-01-01 false Summary disposition. 1780.31 Section 1780.31... Summary disposition. (a) In general. The presiding officer shall recommend that the Director issue a final order granting a motion for summary disposition if the undisputed pleaded facts, admissions,...

  5. 12 CFR 308.29 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 4 2011-01-01 2011-01-01 false Summary disposition. 308.29 Section 308.29... PRACTICE AND PROCEDURE Uniform Rules of Practice and Procedure § 308.29 Summary disposition. (a) In general... a motion for summary disposition if the undisputed pleaded facts, admissions,...

  6. 10 CFR 2.1205 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Summary disposition. 2.1205 Section 2.1205 Energy NUCLEAR... Hearing Procedures for NRC Adjudications § 2.1205 Summary disposition. (a) Unless the presiding officer or the Commission directs otherwise, motions for summary disposition may be submitted to the...

  7. Teaching Dispositions: Shared Understanding for Teacher Preparation

    ERIC Educational Resources Information Center

    DeMuth, Lynn

    2012-01-01

    This qualitative phenomenological study explored the perceptions of 16 high-performing teachers related to teaching dispositions, effects of dispositions on teaching and learning, and recommendations for assessment of teaching dispositions during teacher preparation. Participants' perceptions were gathered using six guided interview questions…

  8. Social Justice and Dispositions for Adult Education

    ERIC Educational Resources Information Center

    Holst, John D.

    2010-01-01

    The article identifies dispositions from a thematic investigation of the pedagogical practice of Ernesto Che Guevara and various social movements in the United States. The article outlines and places these dispositions within the context of debates over social justice and dispositions for education program accreditation in the United States that…

  9. Minority Language Rights.

    ERIC Educational Resources Information Center

    O Riagain, Padraig; Shuibhne, Niamh Nic

    1997-01-01

    A survey of literature since 1990 on minority languages and language rights focuses on five issues: definition of minorities; individual vs. collective rights; legal bases for minority linguistic rights; applications and interpretations of minority language rights; and assessments of the impact of minority rights legislation. A nine-item annotated…

  10. Fundamental thermodynamics of actinide-bearing mineral waste forms. 1998 annual progress report

    SciTech Connect

    Williamson, M.A.; Ebbinghaus, B.B.

    1998-06-01

    'The end of the Cold War raised the need for the technical community to be concerned with the disposition of excess nuclear weapon material. The plutonium will either be converted into mixed-oxide fuel for use in nuclear reactors or immobilized in glass or ceramic waste forms and placed in a repository. The stability and behavior of plutonium in the ceramic materials as well as the phase behavior and stability of the ceramic material in the environment is not well established. In order to provide technically sound solutions to these issues, thermodynamic data are essential in developing an understanding of the chemistry and phase equilibria of the actinide-bearing mineral waste form materials proposed as immobilization matrices. Mineral materials of interest include zircon, zirconolite, and pyrochlore. High temperature solution calorimetry is one of the most powerful techniques, sometimes the only technique, for providing the fundamental thermodynamic data needed to establish optimum material fabrication parameters, and more importantly, understand and predict the behavior of the mineral materials in the environment. The purpose of this project is to experimentally determine the enthalpy of formation of actinide orthosilicates, the enthalpy of formation of actinide substituted zircon, zirconolite and pyrochlore, and develop an understanding of the bonding characteristics and stability of these materials. This report summarizes work after eight months of a three year project.'

  11. Fundamental Thermodynamics of Actinide-Bearing Mineral Waste Forms - Final Report

    SciTech Connect

    Williamson, Mark A.; Ebbinghaus, Bartley B.; Navrotsky, Alexandra

    2001-03-01

    The end of the Cold War raised the need for the technical community to be concerned with the disposition of excess nuclear weapon material. The plutonium will either be converted into mixed-oxide fuel for use in nuclear reactors or immobilized in glass or ceramic waste forms and placed in a repository. The stability and behavior of plutonium in the ceramic materials as well as the phase behavior and stability of the ceramic material in the environment is not well established. In order to provide technically sound solutions to these issues, thermodynamic data are essential in developing an understanding of the chemistry and phase equilibria of the actinide-bearing mineral waste form materials proposed as immobilization matrices. Mineral materials of interest include zircon, zirconolite, and pyrochlore. High temperature solution calorimetry is one of the most powerful techniques, sometimes the only technique, for providing the fundamental thermodynamic data needed to establish optimum material fabrication parameters, and more importantly understand and predict the behavior of the mineral materials in the environment. The purpose of this project is to experimentally determine the enthalpy of formation of actinide orthosilicates, the enthalpies of formation of actinide substituted zirconolite and pyrochlore, and develop an understanding of the bonding characteristics and stabilities of these materials.

  12. Whatever Happened to Productive Disposition?

    ERIC Educational Resources Information Center

    Grady, Maureen

    2016-01-01

    In 2001, Kilpatrick, Swafford, and Findell proposed a new way to look at what it means for students to be mathematically proficient. They described mathematical proficiency as comprising five intertwined strands: procedural fluency, conceptual understanding, adaptive reasoning, strategic competence, and productive disposition. The vision is that…

  13. Sex Differences in Drug Disposition

    PubMed Central

    Soldin, Offie P.; Chung, Sarah H.; Mattison, Donald R.

    2011-01-01

    Physiological, hormonal, and genetic differences between males and females affect the prevalence, incidence, and severity of diseases and responses to therapy. Understanding these differences is important for designing safe and effective treatments. This paper summarizes sex differences that impact drug disposition and includes a general comparison of clinical pharmacology as it applies to men and women. PMID:21403873

  14. Signs, dispositions, and semiotic scaffolding.

    PubMed

    Fernández, Eliseo

    2015-12-01

    In theoretical work we distinguish living beings from inanimate objects on the basis of some paramount attributes, such as agency and autonomy. These abstract features are not directly accessible to our scrutiny, but we surmise their nature through observation of the purpose-oriented behavior of organisms. I intend to show that organismal purposefulness springs from the intrinsic, constitutive kind of finality that is the hallmark of all semiotic transactions. To this aim I develop a dispositionalist account of organismal causation based on a distinction between two kinds of causal dispositions: fixed (efficient) dispositions and traveling dispositions. Fixed dispositions are rigidly attached to physical structures and processes; these are the dispositions regularly invoked in current discussions of causal explanation. Traveling dispositions are able to move freely from one location to another by becoming embodied into suitable supporting media. I introduce these notions to articulate a view of semiosis I deem best suited to the life sciences, and contend that sign tokens are vehicles of traveling dispositions. This account places the origin of purposive behavior at the interaction of physical and semiotic causation. To properly motivate the discussion I briefly review some recent developments in the philosophy of science concerning various forms of causation invoked by scientists across disciplines to frame explanations and make predictions. The ensuing discussion gives particular prominence to mechanistic (as distinct from mechanicist) explanatory accounts of biological phenomena. This review is followed by a brief characterization of a "nomological machine," a comprehensive schema introduced and developed by Nancy Cartwright with the goal of explaining causal mechanisms in a general setting. By capitalizing on this model's heuristic virtues I seek to formulate a compelling view of the interactions between physical and semiotic causation at play in semiotic

  15. Decontamination of matrices containing actinide oxides

    SciTech Connect

    Villarreal, Robert

    1997-12-01

    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) washing the undissolved matrix material to remove any residual materials; and (e) drying and returning the treated matrix material to the environment.

  16. Experimental studies of actinides in molten salts

    SciTech Connect

    Reavis, J.G.

    1985-06-01

    This review stresses techniques used in studies of molten salts containing multigram amounts of actinides exhibiting intense alpha activity but little or no penetrating gamma radiation. The preponderance of studies have used halides because oxygen-containing actinide compounds (other than oxides) are generally unstable at high temperatures. Topics discussed here include special enclosures, materials problems, preparation and purification of actinide elements and compounds, and measurements of various properties of the molten volts. Property measurements discussed are phase relationships, vapor pressure, density, viscosity, absorption spectra, electromotive force, and conductance. 188 refs., 17 figs., 6 tabs.

  17. Actinide removal from spent salts

    DOEpatents

    Hsu, Peter C.; von Holtz, Erica H.; Hipple, David L.; Summers, Leslie J.; Adamson, Martyn G.

    2002-01-01

    A method for removing actinide contaminants (uranium and thorium) from the spent salt of a molten salt oxidation (MSO) reactor is described. Spent salt is removed from the reactor and analyzed to determine the contaminants present and the carbonate concentration. The salt is dissolved in water, and one or more reagents are added to precipitate the thorium as thorium oxide and/or the uranium as either uranium oxide or as a diuranate salt. The precipitated materials are filtered, dried and packaged for disposal as radioactive waste. About 90% of the thorium and/or uranium present is removed by filtration. After filtration, salt solutions having a carbonate concentration >20% can be dried and returned to the reactor for re-use. Salt solutions containing a carbonate concentration <20% require further clean-up using an ion exchange column, which yields salt solutions that contain less than 0.1 ppm of thorium or uranium.

  18. Subsurface interactions of actinide species and microorganisms : implications for the bioremediation of actinide-organic mixtures.

    SciTech Connect

    Banaszak, J.E.; Reed, D.T.; Rittmann, B.E.

    1999-02-12

    By reviewing how microorganisms interact with actinides in subsurface environments, we assess how bioremediation controls the fate of actinides. Actinides often are co-contaminants with strong organic chelators, chlorinated solvents, and fuel hydrocarbons. Bioremediation can immobilize the actinides, biodegrade the co-contaminants, or both. Actinides at the IV oxidation state are the least soluble, and microorganisms accelerate precipitation by altering the actinide's oxidation state or its speciation. We describe how microorganisms directly oxidize or reduce actinides and how microbiological reactions that biodegrade strong organic chelators, alter the pH, and consume or produce precipitating anions strongly affect actinide speciation and, therefore, mobility. We explain why inhibition caused by chemical or radiolytic toxicities uniquely affects microbial reactions. Due to the complex interactions of the microbiological and chemical phenomena, mathematical modeling is an essential tool for research on and application of bioremediation involving co-contamination with actinides. We describe the development of mathematical models that link microbiological and geochemical reactions. Throughout, we identify the key research needs.

  19. Overview of actinide chemistry in the WIPP

    SciTech Connect

    Borkowski, Marian; Lucchini, Jean - Francois; Richmann, Michael K; Reed, Donald T; Khaing, Hnin; Swanson, Juliet

    2009-01-01

    The year 2009 celebrates 10 years of safe operations at the Waste Isolation Pilot Plant (WIPP), the only nuclear waste repository designated to dispose defense-related transuranic (TRU) waste in the United States. Many elements contributed to the success of this one-of-the-kind facility. One of the most important of these is the chemistry of the actinides under WIPP repository conditions. A reliable understanding of the potential release of actinides from the site to the accessible environment is important to the WIPP performance assessment (PA). The environmental chemistry of the major actinides disposed at the WIPP continues to be investigated as part of the ongoing recertification efforts of the WIPP project. This presentation provides an overview of the actinide chemistry for the WIPP repository conditions. The WIPP is a salt-based repository; therefore, the inflow of brine into the repository is minimized, due to the natural tendency of excavated salt to re-seal. Reducing anoxic conditions are expected in WIPP because of microbial activity and metal corrosion processes that consume the oxygen initially present. Should brine be introduced through an intrusion scenario, these same processes will re-establish reducing conditions. In the case of an intrusion scenario involving brine, the solubilization of actinides in brine is considered as a potential source of release to the accessible environment. The following key factors establish the concentrations of dissolved actinides under subsurface conditions: (1) Redox chemistry - The solubility of reduced actinides (III and IV oxidation states) is known to be significantly lower than the oxidized forms (V and/or VI oxidation states). In this context, the reducing conditions in the WIPP and the strong coupling of the chemistry for reduced metals and microbiological processes with actinides are important. (2) Complexation - For the anoxic, reducing and mildly basic brine systems in the WIPP, the most important

  20. Electronic structure and correlation effects in actinides

    SciTech Connect

    Albers, R.C.

    1998-12-01

    This report consists of the vugraphs given at a conference on electronic structure. Topics discussed are electronic structure, f-bonding, crystal structure, and crystal structure stability of the actinides and how they are inter-related.

  1. Advanced Aqueous Separation Systems for Actinide Partitioning

    SciTech Connect

    Nash, Kenneth L.; Clark, Sue; Meier, G Patrick; Alexandratos, Spiro; Paine, Robert; Hancock, Robert; Ensor, Dale

    2012-03-21

    One of the most challenging aspects of advanced processing of spent nuclear fuel is the need to isolate transuranium elements from fission product lanthanides. This project expanded the scope of earlier investigations of americium (Am) partitioning from the lanthanides with the synthesis of new separations materials and a centralized focus on radiochemical characterization of the separation systems that could be developed based on these new materials. The primary objective of this program was to explore alternative materials for actinide separations and to link the design of new reagents for actinide separations to characterizations based on actinide chemistry. In the predominant trivalent oxidation state, the chemistry of lanthanides overlaps substantially with that of the trivalent actinides and their mutual separation is quite challenging.

  2. Joint Actinide Shock Physics Experimental Research - JASPER

    ScienceCinema

    None

    2015-01-09

    Commonly known as JASPER the Joint Actinide Shock Physics Experimental Research facility is a two stage light gas gun used to study the behavior of plutonium and other materials under high pressures, temperatures, and strain rates.

  3. Joint Actinide Shock Physics Experimental Research - JASPER

    SciTech Connect

    2014-10-31

    Commonly known as JASPER the Joint Actinide Shock Physics Experimental Research facility is a two stage light gas gun used to study the behavior of plutonium and other materials under high pressures, temperatures, and strain rates.

  4. Preparation of actinide targets by electrodeposition

    NASA Astrophysics Data System (ADS)

    Trautmann, N.; Folger, H.

    1989-10-01

    Actinide targets with varying thicknesses on different substrates have been prepared by electrodeposition either from aqueous solutions or from solutions of their nitrates in isopropyl alcohol. With these techniques the actinides can be deposited almost quantitatively on various backing materials within 15 to 30 min. Targets of thorium, uranium, neptunium, plutonium, americium, curium and californium with areal densities from almost carrier-free up to 1.4 mg/cm 2 on thin beryllium, carbon, titanium, tantalum and platinum foils have been prepared. In most cases, prior to the deposition, the actinides had to be purified chemically and for some of them, due to the limited amount of material available, recycling procedures were required. Applications of actinide targets in heavy-ion reactions are briefly discussed.

  5. PREPARATION OF ACTINIDE-ALUMINUM ALLOYS

    DOEpatents

    Moore, R.H.

    1962-09-01

    BS>A process is given for preparing alloys of aluminum with plutonium, uranium, and/or thorium by chlorinating actinide oxide dissolved in molten alkali metal chloride with hydrochloric acid, chlorine, and/or phosgene, adding aluminum metal, and passing air and/or water vapor through the mass. Actinide metal is formed and alloyed with the aluminum. After cooling to solidification, the alloy is separated from the salt. (AEC)

  6. Synergism of trivalent actinides and lanthanides

    SciTech Connect

    Mathur, J.N.

    1983-01-01

    The synergism of trivalent actinides and lanthanides has been reviewed critically. Different systems including ..beta..-di-ketones and several other chelating agents with various neutral donors have been discussed. The thermodynamic parameters, effect of diluents, auto-synergism and synergism with eutectic mixtures have been discussed in the case of trivalent actinides and lanthanides. Also the mechanism of synergism and the various possible uses of this phenomenon have been referred to with the possible data available. 160 references, 4 tables.

  7. Structural and magnetic characterization of actinide materials

    SciTech Connect

    Cort, B.; Allen, T.H.; Lawson, A.C.

    1998-12-31

    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. Specific subject areas are developing neutron diffraction techniques for smaller actinide samples; modeling of inelastic scattering data for actinide metal hydrides; characterizing actinide oxide structures; and investigating aging effects in actinides. These studies utilize neutron scattering supported by equilibrium studies, kinetics, and x-ray diffraction. Major accomplishments include (1) development of encapsulation techniques for small actinide samples and neutron diffraction studies of AmD{sub 2.4} and PuO{sub 2.3}; (2) refinement of lattice dynamics model to elucidate hydrogen-hydrogen and hydrogen-metal interactions in rare-earth and actinide hydrides; (3) kinetic studies with PuO{sub 2} indicating that the recombination reaction is faster than radiolytic decomposition of adsorbed water but a chemical reaction produces H{sub 2}; (4) PVT studies of the reaction between PuO{sub 2} and water demonstrate that PuO{sub 2+x} and H{sub 2} form and that PuO{sub 2} is not the thermodynamically stable form of the oxide in air; and (5) model calculations of helium in growth in aged plutonium predicting bubble formation only at grain boundaries at room temperature. The work performed in this project has application to fundamental properties of actinides, aging, and long-term storage of plutonium.

  8. Human factors and safety issues associated with actinide retrieval from spent light water reactor fuel assemblies

    SciTech Connect

    Spelt, P.F.

    1992-01-01

    A major problem in environmental restoration and waste management is the disposition of used fuel assemblies from the many light water reactors in the United States, which present a radiation hazard to those whose job is to dispose of them, with a similar threat to the general environment associated with long-term storage in fuel repositories around the country. Actinides resident in the fuel pins as a result of their use in reactor cores constitute a significant component of this hazard. Recently, the Department of Energy has initiated an Actinide Recycle Program to study the feasibility of using pyrochemical (molten salt) processes to recover actinides from the spent fuel assemblies of commercial reactors. This project concerns the application of robotics technology to the operation and maintenance functions of a plant whose objective is to recover actinides from spent fuel assemblies, and to dispose of the resulting hardware and chemical components from this process. Such a procedure involves a number of safety and human factors issues. The purpose of the project is to explore the use of robotics and artificial intelligence to facilitate accomplishment of the program goals while maintaining the safety of the humans doing the work and the integrity of the environment. This project will result in a graphic simulation on a Silicon Graphics workstation as a proof of principle demonstration of the feasibility of using robotics along with an intelligent operator interface. A major component of the operator-system interface is a hybrid artificial intelligence system developed at Oak Ridge National Laboratory, which combines artificial neural networks and an expert system into a hybrid, self-improving computer-based system interface. 10 refs.

  9. Human factors and safety issues associated with actinide retrieval from spent light water reactor fuel assemblies

    SciTech Connect

    Spelt, P.F.

    1992-08-01

    A major problem in environmental restoration and waste management is the disposition of used fuel assemblies from the many light water reactors in the United States, which present a radiation hazard to those whose job is to dispose of them, with a similar threat to the general environment associated with long-term storage in fuel repositories around the country. Actinides resident in the fuel pins as a result of their use in reactor cores constitute a significant component of this hazard. Recently, the Department of Energy has initiated an Actinide Recycle Program to study the feasibility of using pyrochemical (molten salt) processes to recover actinides from the spent fuel assemblies of commercial reactors. This project concerns the application of robotics technology to the operation and maintenance functions of a plant whose objective is to recover actinides from spent fuel assemblies, and to dispose of the resulting hardware and chemical components from this process. Such a procedure involves a number of safety and human factors issues. The purpose of the project is to explore the use of robotics and artificial intelligence to facilitate accomplishment of the program goals while maintaining the safety of the humans doing the work and the integrity of the environment. This project will result in a graphic simulation on a Silicon Graphics workstation as a proof of principle demonstration of the feasibility of using robotics along with an intelligent operator interface. A major component of the operator-system interface is a hybrid artificial intelligence system developed at Oak Ridge National Laboratory, which combines artificial neural networks and an expert system into a hybrid, self-improving computer-based system interface. 10 refs.

  10. Rapid determination of actinides in seawater samples

    DOE PAGESBeta

    Maxwell, Sherrod L.; Culligan, Brian K.; Hutchison, Jay B.; Utsey, Robin C.; McAlister, Daniel R.

    2014-03-09

    A new rapid method for the determination of actinides in seawater samples has been developed at the Savannah River National Laboratory. The actinides can be measured by alpha spectrometry or inductively-coupled plasma mass spectrometry. The new method employs novel pre-concentration steps to collect the actinide isotopes quickly from 80 L or more of seawater. Actinides are co-precipitated using an iron hydroxide co-precipitation step enhanced with Ti+3 reductant, followed by lanthanum fluoride co-precipitation. Stacked TEVA Resin and TRU Resin cartridges are used to rapidly separate Pu, U, and Np isotopes from seawater samples. TEVA Resin and DGA Resin were used tomore » separate and measure Pu, Am and Cm isotopes in seawater volumes up to 80 L. This robust method is ideal for emergency seawater samples following a radiological incident. It can also be used, however, for the routine analysis of seawater samples for oceanographic studies to enhance efficiency and productivity. In contrast, many current methods to determine actinides in seawater can take 1–2 weeks and provide chemical yields of ~30–60 %. This new sample preparation method can be performed in 4–8 h with tracer yields of ~85–95 %. By employing a rapid, robust sample preparation method with high chemical yields, less seawater is needed to achieve lower or comparable detection limits for actinide isotopes with less time and effort.« less

  11. Recent progress in actinide borate chemistry

    SciTech Connect

    Wang, Shuao; Alekseev, Evgeny V.; Depmeier, Wulf; Albrecht-Schmitt, Thomas E.

    2011-01-01

    The use of molten boric acid as a reactive flux for synthesizing actinide borates has been developed in the past two years providing access to a remarkable array of exotic materials with both unusual structures and unprecedented properties. [ThB₅O₆(OH)₆][BO(OH)₂]·2.5H₂O possesses a cationic supertetrahedral structure and displays remarkable anion exchange properties with high selectivity for TcO4- Uranyl borates form noncentrosymmetric structures with extraordinarily rich topological relationships. Neptunium borates are often mixed-valent and yield rare examples of compounds with one metal in three different oxidation states. Plutonium borates display new coordination chemistry for trivalent actinides. Finally, americium borates show a dramatic departure from plutonium borates, and there are scant examples of families of actinides compounds that extend past plutonium to examine the bonding of later actinides. There are several grand challenges that this work addresses. The foremost of these challenges is the development of structure-property relationships in transuranium materials. A deep understanding of the materials chemistry of actinides will likely lead to the development of advanced waste forms for radionuclides present in nuclear waste that prevent their transport in the environment. This work may have also uncovered the solubility-limiting phases of actinides in some repositories, and allows for measurements on the stability of these materials.

  12. Recent progress in actinide borate chemistry.

    PubMed

    Wang, Shuao; Alekseev, Evgeny V; Depmeier, Wulf; Albrecht-Schmitt, Thomas E

    2011-10-21

    The use of molten boric acid as a reactive flux for synthesizing actinide borates has been developed in the past two years providing access to a remarkable array of exotic materials with both unusual structures and unprecedented properties. [ThB(5)O(6)(OH)(6)][BO(OH)(2)]·2.5H(2)O possesses a cationic supertetrahedral structure and displays remarkable anion exchange properties with high selectivity for TcO(4)(-). Uranyl borates form noncentrosymmetric structures with extraordinarily rich topological relationships. Neptunium borates are often mixed-valent and yield rare examples of compounds with one metal in three different oxidation states. Plutonium borates display new coordination chemistry for trivalent actinides. Finally, americium borates show a dramatic departure from plutonium borates, and there are scant examples of families of actinides compounds that extend past plutonium to examine the bonding of later actinides. There are several grand challenges that this work addresses. The foremost of these challenges is the development of structure-property relationships in transuranium materials. A deep understanding of the materials chemistry of actinides will likely lead to the development of advanced waste forms for radionuclides present in nuclear waste that prevent their transport in the environment. This work may have also uncovered the solubility-limiting phases of actinides in some repositories, and allows for measurements on the stability of these materials. PMID:21915396

  13. Rapid determination of actinides in seawater samples

    SciTech Connect

    Maxwell, Sherrod L.; Culligan, Brian K.; Hutchison, Jay B.; Utsey, Robin C.; McAlister, Daniel R.

    2014-03-09

    A new rapid method for the determination of actinides in seawater samples has been developed at the Savannah River National Laboratory. The actinides can be measured by alpha spectrometry or inductively-coupled plasma mass spectrometry. The new method employs novel pre-concentration steps to collect the actinide isotopes quickly from 80 L or more of seawater. Actinides are co-precipitated using an iron hydroxide co-precipitation step enhanced with Ti+3 reductant, followed by lanthanum fluoride co-precipitation. Stacked TEVA Resin and TRU Resin cartridges are used to rapidly separate Pu, U, and Np isotopes from seawater samples. TEVA Resin and DGA Resin were used to separate and measure Pu, Am and Cm isotopes in seawater volumes up to 80 L. This robust method is ideal for emergency seawater samples following a radiological incident. It can also be used, however, for the routine analysis of seawater samples for oceanographic studies to enhance efficiency and productivity. In contrast, many current methods to determine actinides in seawater can take 1–2 weeks and provide chemical yields of ~30–60 %. This new sample preparation method can be performed in 4–8 h with tracer yields of ~85–95 %. By employing a rapid, robust sample preparation method with high chemical yields, less seawater is needed to achieve lower or comparable detection limits for actinide isotopes with less time and effort.

  14. MANTRA: Measuring Neutron Capture Cross Sections in Actinides with Accelerator Mass Spectrometry

    NASA Astrophysics Data System (ADS)

    Bauder, W.; Pardo, R. C.; Collon, P.; Palchan, T.; Scott, R.; Vondrasek, R.; Nusair, O.; Nair, C.; Paul, M.; Kondev, F.; Chen, J.; Youinou, G.; Salvatores, M.; Palmotti, G.; Berg, J.; Maddock, T.; Imel, G.

    2013-10-01

    With rising global energy needs, there is substantial interest in nuclear energy research. To explore possibilities for advanced fuel cycles, better neutron cross section data are needed for the minor actinides. The MANTRA (Measurement of Actinide Neutron TRAsmutation) project will improve these data by measuring integral (n, γ) cross sections. The cross sections will be extracted by measuring isotopic ratios in pure actinide samples, irradiated in the Advanced Test Reactor at Idaho National Lab, using Accelerator Mass Spectrometry(AMS) at the Argonne Tandem Linac Accelerator System (ATLAS). MANTRA presents a unique AMS challenge because of the goal to measure multiple isotopic ratios on a large number of samples. To meet these challenges, we have modified the AMS setup at ATLAS to include a laser ablation system for solid material injection into our ECR ion source. I will present work on the laser ablation system and modified source geometry, as well as preliminary measurements of unirradiated actinide samples at ATLAS. This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357.

  15. Performance Comparison of Metallic, Actinide Burning Fuel in Lead-Bismuth and Sodium Cooled Fast Reactors

    SciTech Connect

    Weaver, Kevan Dean; Herring, James Stephen; Mac Donald, Philip Elsworth

    2001-04-01

    Various methods have been proposed to “incinerate” or “transmutate” the current inventory of trans-uranic waste (TRU) that exits in spent light-water-reactor (LWR) fuel, and weapons plutonium. These methods include both critical (e.g., fast reactors) and non-critical (e.g., accelerator transmutation) systems. The work discussed here is part of a larger effort at the Idaho National Engineering and Environmental Laboratory (INEEL) and at the Massachusetts Institute of Technology (MIT) to investigate the suitability of lead and lead-alloy cooled fast reactors for producing low-cost electricity as well as for actinide burning. The neutronics of non-fertile fuel loaded with 20 or 30-wt% light water reactor (LWR) plutonium plus minor actinides for use in a lead-bismuth cooled fast reactor are discussed in this paper, with an emphasis on the fuel cycle life and isotopic content. Calculations show that the average actinide burn rate is similar for both the sodium and lead-bismuth cooled cases ranging from -1.02 to -1.16 g/MWd, compared to a typical LWR actinide generation rate of 0.303 g/MWd. However, when using the same parameters, the sodium-cooled case went subcritical after 0.2 to 0.8 effective full power years, and the lead-bismuth cooled case ranged from 1.5 to 4.5 effective full power years.

  16. Hydrophilic Clicked 2,6-Bis-triazolyl-pyridines Endowed with High Actinide Selectivity and Radiochemical Stability: Toward a Closed Nuclear Fuel Cycle.

    PubMed

    Macerata, Elena; Mossini, Eros; Scaravaggi, Stefano; Mariani, Mario; Mele, Andrea; Panzeri, Walter; Boubals, Nathalie; Berthon, Laurence; Charbonnel, Marie-Christine; Sansone, Francesco; Arduini, Arturo; Casnati, Alessandro

    2016-06-15

    There is still an evident need for selective and stable ligands able to separate actinide(III) from lanthanide(III) metal ions in view of the treatment of the accumulated radioactive waste and of the recycling of minor actinides. We have herein demonstrated that hydrophilic 2,6-bis-triazolyl-pyridines are able to strip all actinides in all the different oxidation states from a diglycolamide-containing kerosene solution into an acidic aqueous phase. The ascertained high actinide selectivity, efficiency, extraction kinetics, and chemical/radiolytic stability spotlight this hydrophilic class of ligands as exceptional candidates for advanced separation processes fundamental for closing the nuclear fuel cycle and solving the environmental issues related to the management of existing nuclear waste. PMID:27203357

  17. 19 CFR 174.22 - Accelerated disposition of protest.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Accelerated disposition of protest. 174.22 Section... OF THE TREASURY (CONTINUED) PROTESTS Review and Disposition of Protests § 174.22 Accelerated disposition of protest. (a) Request for accelerated disposition. Accelerated disposition of a protest filed...

  18. The Difficulty of Teacher Dispositions: Considering Professional Dispositions for Preservice English Teachers

    ERIC Educational Resources Information Center

    Shoffner, Melanie; Sedberry, Tiffany; Alsup, Janet; Johnson, Tara Star

    2014-01-01

    This article explores the place of teacher dispositions in English teacher preparation by contextualizing the issue of dispositions in English teacher preparation. This allows consideration for the importance of developing professional dispositions during English teacher preparation by recognizing that various stakeholders (teacher educators,…

  19. 7 CFR 984.456 - Disposition of reserve walnuts and walnuts used for reserve disposition credit.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Disposition of reserve walnuts and walnuts used for..., Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Administrative Rules and Regulations § 984.456 Disposition of reserve walnuts and walnuts used for reserve disposition credit. (a)...

  20. 7 CFR 984.456 - Disposition of reserve walnuts and walnuts used for reserve disposition credit.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Disposition of reserve walnuts and walnuts used for..., NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Administrative Rules and Regulations § 984.456 Disposition of reserve walnuts and walnuts used for reserve disposition credit. (a)...

  1. 7 CFR 984.456 - Disposition of reserve walnuts and walnuts used for reserve disposition credit.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Disposition of reserve walnuts and walnuts used for..., Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Administrative Rules and Regulations § 984.456 Disposition of reserve walnuts and walnuts used for reserve disposition credit. (a)...

  2. 7 CFR 984.456 - Disposition of reserve walnuts and walnuts used for reserve disposition credit.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Disposition of reserve walnuts and walnuts used for..., Nuts), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Administrative Rules and Regulations § 984.456 Disposition of reserve walnuts and walnuts used for reserve disposition credit. (a)...

  3. 7 CFR 984.456 - Disposition of reserve walnuts and walnuts used for reserve disposition credit.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Disposition of reserve walnuts and walnuts used for..., NUTS), DEPARTMENT OF AGRICULTURE WALNUTS GROWN IN CALIFORNIA Administrative Rules and Regulations § 984.456 Disposition of reserve walnuts and walnuts used for reserve disposition credit. (a)...

  4. Sigma Team for Advanced Actinide Recycle FY2015 Accomplishments and Directions

    SciTech Connect

    Moyer, Bruce A.

    2015-09-30

    The Sigma Team for Minor Actinide Recycle (STAAR) has made notable progress in FY 2015 toward the overarching goal to develop more efficient separation methods for actinides in support of the United States Department of Energy (USDOE) objective of sustainable fuel cycles. Research in STAAR has been emphasizing the separation of americium and other minor actinides (MAs) to enable closed nuclear fuel recycle options mainly within the paradigm of aqueous reprocessing of used oxide nuclear fuel dissolved in nitric acid. Its major scientific challenge concerns achieving selectivity for trivalent actinides vs lanthanides. Not only is this challenge yielding to research advances, but technology concepts such as ALSEP (Actinide Lanthanide Separation) are maturing toward demonstration readiness. Efforts are organized in five task areas: 1) combining bifunctional neutral extractants with an acidic extractant to form a single process solvent, developing a process flowsheet, and demonstrating it at bench scale; 2) oxidation of Am(III) to Am(VI) and subsequent separation with other multivalent actinides; 3) developing an effective soft-donor solvent system for An(III) selective extraction using mixed N,O-donor or all-N donor extractants such as triazinyl pyridine compounds; 4) testing of inorganic and hybrid-type ion exchange materials for MA separations; and 5) computer-aided molecular design to identify altogether new extractants and complexants and theory-based experimental data interpretation. Within these tasks, two strategies are employed, one involving oxidation of americium to its pentavalent or hexavalent state and one that seeks to selectively complex trivalent americium either in the aqueous phase or the solvent phase. Solvent extraction represents the primary separation method employed, though ion exchange and crystallization play an important role. Highlights of accomplishments include: Confirmation of the first-ever electrolytic oxidation of Am(III) in a

  5. A measurement of actinide neutron transmutations with accelerator mass spectrometry in order to infer neutron capture cross sections

    NASA Astrophysics Data System (ADS)

    Bauder, William K.

    Improved neutron capture cross section data for transuranic and minor actinides are essential for assessing possibilities for next generation reactors and advanced fuel cycles. The Measurement of Actinide Neutron TRAnsmutation (MANTRA) project aims to make a comprehensive set of energy integrated neutron capture cross section measurements for all relevant isotopes from Th to Cf. The ability to extract these cross sections relies on the use of Accelerator Mass Spectrometry (AMS) to analyze isotopic concentrations in samples irradiated in the Advanced Test Reactor (ATR). The AMS measurements were performed at the Argonne Tandem Linear Accelerator System (ATLAS) and required a number of key technical developments to the ion source, accelerator, and detector setup. In particular, a laser ablation material injection system was developed at the electron cyclotron resonance ion source. This system provides a more effective method to produce ion beams from samples containing only 1% actinide material and offers some benefits for reducing cross talk in the source. A series of four actinide measurements are described in this dissertation. These measurements represent the most substantial AMS work attempted at ATLAS and the first results of the MANTRA project. Isotopic ratios for one and two neutron captures were measured in each sample with total uncertainties around 10%. These results can be combined with a MCNP model for the neutron fluence to infer actinide neutron capture cross sections.

  6. TUCS/phosphate mineralization of actinides

    SciTech Connect

    Nash, K.L.

    1997-10-01

    This program has as its objective the development of a new technology that combines cation exchange and mineralization to reduce the concentration of heavy metals (in particular actinides) in groundwaters. The treatment regimen must be compatible with the groundwater and soil, potentially using groundwater/soil components to aid in the immobilization process. The delivery system (probably a water-soluble chelating agent) should first concentrate the radionuclides then release the precipitating anion, which forms thermodynamically stable mineral phases, either with the target metal ions alone or in combination with matrix cations. This approach should generate thermodynamically stable mineral phases resistant to weathering. The chelating agent should decompose spontaneously with time, release the mineralizing agent, and leave a residue that does not interfere with mineral formation. For the actinides, the ideal compound probably will release phosphate, as actinide phosphate mineral phases are among the least soluble species for these metals. The most promising means of delivering the precipitant would be to use a water-soluble, hydrolytically unstable complexant that functions in the initial stages as a cation exchanger to concentrate the metal ions. As it decomposes, the chelating agent releases phosphate to foster formation of crystalline mineral phases. Because it involves only the application of inexpensive reagents, the method of phosphate mineralization promises to be an economical alternative for in situ immobilization of radionuclides (actinides in particular). The method relies on the inherent (thermodynamic) stability of actinide mineral phases.

  7. Nonaqueous method for dissolving lanthanide and actinide metals

    DOEpatents

    Crisler, L.R.

    1975-11-11

    Lanthanide and actinide beta-diketonate complex molecular compounds are produced by reacting a beta-diketone compound with a lanthanide or actinide element in the elemental metallic state in a mixture of carbon tetrachloride and methanol.

  8. Ultratrace analysis of transuranic actinides by laser-induced fluorescence

    DOEpatents

    Miller, S.M.

    1983-10-31

    Ultratrace quantities of transuranic actinides are detected indirectly by their effect on the fluorescent emissions of a preselected fluorescent species. Transuranic actinides in a sample are coprecipitated with a host lattice material containing at least one preselected fluorescent species. The actinide either quenches or enhances the laser-induced fluorescence of the preselected fluorescent species. The degree of enhancement or quenching is quantitatively related to the concentration of actinide in the sample.

  9. Ultratrace analysis of transuranic actinides by laser-induced fluorescence

    DOEpatents

    Miller, Steven M.

    1988-01-01

    Ultratrace quantities of transuranic actinides are detected indirectly by their effect on the fluorescent emissions of a preselected fluorescent species. Transuranic actinides in a sample are coprecipitated with a host lattice material containing at least one preselected fluorescent species. The actinide either quenches or enhances the laser-induced fluorescence of the preselected fluorescent species. The degree of enhancement or quenching is quantitatively related to the concentration of actinide in the sample.

  10. Drug Disposition in Pathophysiological Conditions

    PubMed Central

    Gandhi, Adarsh; Moorthy, Bhagavatula; Ghose, Romi

    2014-01-01

    Expression and activity of several key drug metabolizing enzymes (DMEs) and transporters are altered in various pathophysiological conditions, leading to altered drug metabolism and disposition. This can have profound impact on the pharmacotherapy of widely used clinically relevant medications in terms of safety and efficacy by causing inter-individual variabilities in drug responses. This review article highlights altered drug disposition in inflammation and infectious diseases, and commonly encountered disorders such as cancer, obesity/diabetes, fatty liver diseases, cardiovascular diseases and rheumatoid arthritis. Many of the clinically relevant drugs have a narrow therapeutic index. Thus any changes in the disposition of these drugs may lead to reduced efficacy and increased toxicity. The implications of changes in DMEs and transporters on the pharmacokinetics/pharmacodynamics of clinically-relevant medications are also discussed. Inflammation-mediated release of pro-inflammatory cytokines and activation of toll-like receptors (TLRs) are known to play a major role in down-regulation of DMEs and transporters. Although the mechanism by which this occurs is unclear, several studies have shown that inflammation-associated cell-signaling pathway and its interaction with basal transcription factors and nuclear receptors in regulation of DMEs and transporters play a significant role in altered drug metabolism. Altered regulation of DMEs and transporters in a multitude of disease states will contribute towards future development of powerful in vitro and in vivo tools in predicting the drug response and opt for better drug design and development. The goal is to facilitate a better understanding of the mechanistic details underlying the regulation of DMEs and transporters in pathophysiological conditions. PMID:22746301

  11. Drug disposition in pathophysiological conditions.

    PubMed

    Gandhi, Adarsh; Moorthy, Bhagavatula; Ghose, Romi

    2012-11-01

    Expression and activity of several key drug metabolizing enzymes (DMEs) and transporters are altered in various pathophysiological conditions, leading to altered drug metabolism and disposition. This can have profound impact on the pharmacotherapy of widely used clinically relevant medications in terms of safety and efficacy by causing inter-individual variabilities in drug responses. This review article highlights altered drug disposition in inflammation and infectious diseases, and commonly encountered disorders such as cancer, obesity/diabetes, fatty liver diseases, cardiovascular diseases and rheumatoid arthritis. Many of the clinically relevant drugs have a narrow therapeutic index. Thus any changes in the disposition of these drugs may lead to reduced efficacy and increased toxicity. The implications of changes in DMEs and transporters on the pharmacokinetics/pharmacodynamics of clinically-relevant medications are also discussed. Inflammation-mediated release of pro-inflammatory cytokines and activation of toll-like receptors (TLRs) are known to play a major role in down-regulation of DMEs and transporters. Although the mechanism by which this occurs is unclear, several studies have shown that inflammation-associated cell-signaling pathway and its interaction with basal transcription factors and nuclear receptors in regulation of DMEs and transporters play a significant role in altered drug metabolism. Altered regulation of DMEs and transporters in a multitude of disease states will contribute towards future development of powerful in vitro and in vivo tools in predicting the drug response and opt for better drug design and development. The goal is to facilitate a better understanding of the mechanistic details underlying the regulation of DMEs and transporters in pathophysiological conditions. PMID:22746301

  12. Materials in Nuclear Waste Disposition

    NASA Astrophysics Data System (ADS)

    Rebak, Raul B.

    2014-03-01

    Commercial nuclear energy has been used for over 6 decades; however, to date, none of the 30+ countries with nuclear power has opened a repository for high-level waste (HLW). All countries with nuclear waste plan to dispose of it in metallic containers located in underground geologically stable repositories. Some countries also have liquid nuclear waste that needs to be reduced and vitrified before disposition. The five articles included in this topic offer a cross section of the importance of alloy selection to handle nuclear waste at the different stages of waste processing and disposal.

  13. THEORY FOR THE XPS OF ACTINIDES

    SciTech Connect

    Bagus, Paul S.; Ilton, Eugene S.

    2013-08-01

    Two aspects of the electronic structure of actinide oxides that significantly affect the XPS spectra are described; these aspects are also important for the materials properties of the oxides. The two aspects considered are: (1) The spin-orbit coupling of the open 5f shell electrons in actinide cations and how this coupling affects the electronic structure. And, (2) the covalent character of the metal oxygen interaction in actinide compounds. Because of this covalent character, there are strong departures from the nominal oxidation states that are significantly larger in core-hole states than in the ground state. The consequences for the XPS of this covalent character are examined. A proper understanding of the way in which they influence the XPS makes it possible to use the XPS to correctly characterize the electronic structure of the oxides.

  14. Preparation of actinide-metal research materials

    SciTech Connect

    Aaron, W.S.; Culpepper, C.A.; Campbell, K.B.

    1986-01-01

    The preparation of actinide-metal research materials is one of many functions of the Isotope Research Materials Laboratory (IRML) at Oak Ridge National Laboratory. Research samples of uranium, plutonium, americium, and curium, typically from milligram quantities up to approx. 100 g, are prepared as pure metals or alloys to customer specifications. Larger quantities, up to many kilograms, of the lower activity actinides, such as /sup 235/U, /sup 238/U, and /sup 232/Th, are also fabricated into custom research forms. Physical forms of these metals include rolled foils or sheets, castings (ingot, rod, or special shapes), and evaporated or sputtered films. The actinide-metal processing capabilities of the IRML are continuing to be improved and applied to a wide variety of custom material preparations to meet the needs of the world-wide research community.

  15. The Actinide-Lanthanide Separation Process

    SciTech Connect

    Lumetta, Gregg J.; Gelis, Artem V.; Carter, Jennifer C.; Niver, Cynthia M.; Smoot, Margaret R.

    2014-02-21

    The Actinide-Lanthanide SEParation (ALSEP) process is described. The process uses an extractant phase consisting of either N,N,N',N'-tetraoctyldiglycolamide (TODGA) or N,N,N',N'-tetra(2 ethylhexyl)diglycolamide (T2EHDGA) combined with 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (HEH[EHP]). The neutral TODGA or T2EHDGA serves to co-extract the trivalent actinide and lanthanide ions from nitric acid media. Switching the aqueous phase chemistry to a citrate buffered diethylenetriaminepentaacetic acid (DTPA) solution at pH 2.5 to 4 results in selective transfer of the actinides to the aqueous phase, thus resulting in separation of these two groups of elements.

  16. Minority Women's Health

    MedlinePlus

    ... migrant issues Access to health care Language barriers Human trafficking Taking care of your health Immunizations and screenings Sharing family health history Health before pregnancy More... Government in action on minority women's health Minority partnerships ...

  17. Minority Inclusion Programs.

    ERIC Educational Resources Information Center

    Gelfand, M. David

    1995-01-01

    Asserts that the United States has a long, sad history of discrimination against minority rights. Discusses the origins and history of minority inclusion or affirmative action programs. Includes a special report on the "English Only" movement. (CFR)

  18. FINAL REPORT. ACTINIDE-ALUMINATE SPECIATION IN ALKALINE RADIOACTIVE WASTE

    EPA Science Inventory

    Investigation of behavior of actinides in alkaline media containing Al(III) showed that no aluminate complexes of actinides in oxidation states (III-VII) were formed in alkaline solutions. At alkaline precipitation (pH 10-14) of actinides in presence of Al(III) formation of alumi...

  19. RECOVERY OF ACTINIDES FROM AQUEOUS NITRIC ACID SOLUTIONS

    DOEpatents

    Ader, M.

    1963-11-19

    A process of recovering actinides is presented. Tetravalent actinides are extracted from rare earths in an aqueous nitric acid solution with a ketone and back-extracted from the ketone into an aqueous medium. The aqueous actinide solution thus obtained, prior to concentration by boiling, is sparged with steam to reduce its ketone to a maximum content of 3 grams per liter. (AEC)

  20. Complexation of Actinides in Solution: Thermodynamic Measurementsand Structural Characterization

    SciTech Connect

    Rao, L.

    2007-02-01

    This paper presents a brief introduction of the studies of actinide complexation in solution at Lawrence Berkeley National Laboratory. An integrated approach of thermodynamic measurements and structural characterization is taken to obtain fundamental understanding of actinide complexation in solution that is of importance in predicting the behavior of actinides in separation processes and environmental transport.

  1. Disposition of nuclear waste using subcritical accelerator-driven systems

    SciTech Connect

    Venneri, F.; Li, N.; Williamson, M.; Houts, M.; Lawrence, G.

    1998-12-01

    Studies have shown that the repository long-term radiological risk is from the long-lived transuranics and the fission products Tc-99 and I-129, thermal loading concerns arise mainly form the short-lived fission products Sr-90 and Cs-137. In relation to the disposition of nuclear waste, ATW is expected to accomplish the following: (1) destroy over 99.9% of the actinides; (2) destroy over 99.9% of the Tc and I; (3) separate Sr and Cs (short half-life isotopes); (4) separate uranium; (5) produce electricity. In the ATW concept, spent fuel would be shipped to a ATW site where the plutonium, other transuranics and selected long-lived fission products would be destroyed by fission or transmutation in their only pass through the facility. This approach contrasts with the present-day reprocessing practices in Europe and Japan, during which high purity plutonium is produced and used in the fabrication of fresh mixed-oxide fuel (MOX) that is shipped off-site for use in light water reactors.

  2. 7 CFR 1001.3 - Route disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Route disposition. 1001.3 Section 1001.3 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements... Handling Definitions § 1001.3 Route disposition. See § 1000.3....

  3. Evaluation of Calcine Disposition Path Forward

    SciTech Connect

    Birrer, S.A.; Heiser, M.B.

    2003-02-26

    This document describes an evaluation of the baseline and two alternative disposition paths for the final disposition of the calcine wastes stored at the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory. The pathways are evaluated against a prescribed set of criteria and a recommendation is made for the path forward.

  4. Evaluation of Calcine Disposition - Path Forward

    SciTech Connect

    Steve Birrer

    2003-02-01

    This document describes an evaluation of the baseline and two alternative disposition paths for the final disposition of the calcine wastes stored at the Idaho Nuclear Technology and Engineering Center at the Idaho National Engineering and Environmental Laboratory. The pathways are evaluated against a prescribed set of criteria and a recommendation is made for the path forward.

  5. 9 CFR 2.80 - Records, disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Records, disposition. 2.80 Section 2.80 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Records § 2.80 Records, disposition. (a) No dealer, exhibitor,...

  6. 9 CFR 2.80 - Records, disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Records, disposition. 2.80 Section 2.80 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL WELFARE REGULATIONS Records § 2.80 Records, disposition. (a) No dealer, exhibitor,...

  7. Reclaiming the Moral in the Dispositions Debate

    ERIC Educational Resources Information Center

    Burant, Terry J.; Chubbuck, Sharon M.; Whipp, Joan L.

    2007-01-01

    This article addresses the current debates about the definition and assessment of dispositions in teacher education. Competing perspectives on the definitions and assessment of dispositions in teacher education are examined and critiqued, and a renewed commitment to foregrounding the moral nature of teaching is suggested. Recommendations for…

  8. 25 CFR 11.1012 - Dispositional alternatives.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 25 Indians 1 2010-04-01 2010-04-01 false Dispositional alternatives. 11.1012 Section 11.1012 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Juvenile Offender Procedure § 11.1012 Dispositional alternatives. (a) If a...

  9. 25 CFR 11.1012 - Dispositional alternatives.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Dispositional alternatives. 11.1012 Section 11.1012 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Juvenile Offender Procedure § 11.1012 Dispositional alternatives. (a) If a...

  10. 25 CFR 11.1012 - Dispositional alternatives.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Dispositional alternatives. 11.1012 Section 11.1012 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Juvenile Offender Procedure § 11.1012 Dispositional alternatives. (a) If a...

  11. 25 CFR 11.1012 - Dispositional alternatives.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 25 Indians 1 2011-04-01 2011-04-01 false Dispositional alternatives. 11.1012 Section 11.1012 Indians BUREAU OF INDIAN AFFAIRS, DEPARTMENT OF THE INTERIOR LAW AND ORDER COURTS OF INDIAN OFFENSES AND LAW AND ORDER CODE Juvenile Offender Procedure § 11.1012 Dispositional alternatives. (a) If a...

  12. 17 CFR 12.310 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Summary disposition. 12.310 Section 12.310 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION RULES RELATING TO REPARATIONS Rules Applicable to Formal Decisional Proceedings § 12.310 Summary disposition. (a) Filing of motions, answers. Any party who...

  13. 12 CFR 908.51 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... OPERATIONS RULES OF PRACTICE AND PROCEDURE IN HEARINGS ON THE RECORD Pre-Hearing Proceedings § 908.51 Summary... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Summary disposition. 908.51 Section 908.51... order granting a motion for summary disposition if the undisputed pleaded facts, admissions,...

  14. 12 CFR 908.51 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... OPERATIONS RULES OF PRACTICE AND PROCEDURE IN HEARINGS ON THE RECORD Pre-Hearing Proceedings § 908.51 Summary... 12 Banks and Banking 7 2011-01-01 2011-01-01 false Summary disposition. 908.51 Section 908.51... order granting a motion for summary disposition if the undisputed pleaded facts, admissions,...

  15. 17 CFR 12.207 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Summary disposition. 12.207 Section 12.207 Commodity and Securities Exchanges COMMODITY FUTURES TRADING COMMISSION RULES RELATING TO REPARATIONS Rules Applicable to Summary Decisional Proceedings § 12.207 Summary disposition. (a) Filing of motions, answers. Any party who...

  16. Toward a Theory of Dispositional Communicative Competence.

    ERIC Educational Resources Information Center

    Duran, Robert L.; Kelly, Lynne

    This paper proposes a dispositional conceptualization of communicative competence (explaining an individual's cross-contextual performance) that complements the situational approach which assumes competence is context-bound. Dispositional communicative competence is defined as a function of three dimensions (cognitive, affective, and behavioral)…

  17. Teacher Candidate Dispositions: Perspectives of Professional Expectations

    ERIC Educational Resources Information Center

    Wake, Donna; Bunn, Gary

    2016-01-01

    This study describes a programmatic effort to examine dispositions perceptions of teacher candidates entering the profession. Study participants included 114 master's level teaching candidates in their first semester of a nontraditional teacher education program. Teacher candidates scored themselves on a department disposition rubric designed to…

  18. 14 CFR 1214.606 - Postflight disposition.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 5 2013-01-01 2013-01-01 false Postflight disposition. 1214.606 Section 1214.606 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mementos Aboard Space Shuttle Flights § 1214.606 Postflight disposition. The Associate Director, Johnson...

  19. 14 CFR 1214.606 - Postflight disposition.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 5 2012-01-01 2012-01-01 false Postflight disposition. 1214.606 Section 1214.606 Aeronautics and Space NATIONAL AERONAUTICS AND SPACE ADMINISTRATION SPACE FLIGHT Mementos Aboard Space Shuttle Flights § 1214.606 Postflight disposition. The Associate Director, Johnson...

  20. Overview of surplus weapons plutonium disposition

    SciTech Connect

    Rudy, G.

    1996-05-01

    The safe disposition of surplus weapons useable plutonium is a very important and urgent task. While the functions of long term storage and disposition directly relate to the Department`s weapons program and the environmental management program, the focus of this effort is particularly national security and nonproliferation.

  1. 43 CFR 4.1196 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Summary disposition. 4.1196 Section 4.1196 Public Lands: Interior Office of the Secretary of the Interior DEPARTMENT HEARINGS AND APPEALS PROCEDURES... Revocation of Permits Under Section 521(a)(4) of the Act § 4.1196 Summary disposition. (a) In a...

  2. 12 CFR 19.29 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Summary disposition. 19.29 Section 19.29 Banks... Uniform Rules of Practice and Procedure § 19.29 Summary disposition. (a) In general. The administrative law judge shall recommend that the Comptroller issue a final order granting a motion for...

  3. 12 CFR 19.29 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 1 2011-01-01 2011-01-01 false Summary disposition. 19.29 Section 19.29 Banks... Uniform Rules of Practice and Procedure § 19.29 Summary disposition. (a) In general. The administrative law judge shall recommend that the Comptroller issue a final order granting a motion for...

  4. 43 CFR 4.1156 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Summary disposition. 4.1156 Section 4.1156 Public Lands: Interior Office of the Secretary of the Interior DEPARTMENT HEARINGS AND APPEALS PROCEDURES... Assessments of Civil Penalties § 4.1156 Summary disposition. (a) In a civil penalty proceeding where...

  5. 43 CFR 4.1196 - Summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Summary disposition. 4.1196 Section 4.1196 Public Lands: Interior Office of the Secretary of the Interior DEPARTMENT HEARINGS AND APPEALS PROCEDURES... Revocation of Permits Under Section 521(a)(4) of the Act § 4.1196 Summary disposition. (a) In a...

  6. 43 CFR 4.1156 - Summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Summary disposition. 4.1156 Section 4.1156 Public Lands: Interior Office of the Secretary of the Interior DEPARTMENT HEARINGS AND APPEALS PROCEDURES... Assessments of Civil Penalties § 4.1156 Summary disposition. (a) In a civil penalty proceeding where...

  7. Court Dispositions and Rearrest for Intimate Assault

    ERIC Educational Resources Information Center

    Wooldredge, John; Thistlethwaite, Amy

    2005-01-01

    Researchers examining court dispositions and domestic violence recidivism have argued that disposition effectiveness varies by offender characteristics. We extended this research with analyses of 3,662 persons arrested for misdemeanor assaults on intimates in Hamilton County, Ohio. The incidence, prevalence, and time to rearrest are examined for…

  8. Knowledge, Skills, and Dispositions for Diversity

    ERIC Educational Resources Information Center

    Jones, Anne

    2011-01-01

    The purposes of this research are to explore how currently assessed diversity knowledge, diversity skills, and diversity dispositions of pre-service teachers (PST) relate to each other and further to surmise if the presence of diversity knowledge, diversity skills, and diversity dispositions manifests in cultural efficacy and a general cultural…

  9. Dispositions in Education: Nonentities Worth Talking about

    ERIC Educational Resources Information Center

    Splitter, Laurance J.

    2010-01-01

    The concept of dispositions has commanded considerable attention in both philosophy and education. In this essay, Laurance Splitter draws on philosophy to take a fresh look at dispositions in education, specifically teacher education. Bypassing the pitfalls of both subjectivity and crude behaviorism, he proposes a conceptual framework in which…

  10. Elevated concentrations of actinides in mono lake.

    PubMed

    Anderson, R F; Bacon, M P; Brewer, P G

    1982-04-30

    Tetravalent thorium, pentavalent protactinium, hexavalent uranium, and plutonium (oxidation state uncertain) are present in much higher concentrations in Mono Lake, a saline, alkaline lake in eastern central California, than in seawater. Low ratios of actinium to protactinium and of americium to plutonium indicate that the concentrations of trivalent actinides are not similarly enhanced. The elevated concentrations of the ordinarily very insoluble actinides are maintained in solution by natural ligands, which inhibit their chemical removal from the water column, rather than by an unusually large rate of supply. PMID:17735740

  11. Elevated concentrations of actinides in Mono Lake

    SciTech Connect

    Anderson, R.F.; Bacon, M.P.; Brewer, P.G.

    1982-04-30

    Tetravalent thorium, pentavalent protactinium, hexavalent uranium, and plutonium (oxidation state uncertain) are present in much higher concentrations in Mono Lake, a saline, alkaline lake in eastern central California, than in seawater. Low ratios of actinium to protactinium and of americium to plutonium indicate that the concentrations of trivalent actinides are not similarly enhanced. The elevated concentrations of the ordinarily very insoluble actinides are maintained in solution by natural ligands, which inhibit their chemical removal from the water column, rather than by an unusually large rate of supply.

  12. Strong correlations in actinide redox reactions

    NASA Astrophysics Data System (ADS)

    Horowitz, S. E.; Marston, J. B.

    2011-02-01

    Reduction-oxidation (redox) reactions of the redox couples An(VI)/An(V), An(V)/An(IV), and An(IV)/An(III), where An is an element in the family of early actinides (U, Np, and Pu), as well as Am(VI)/Am(V) and Am(V)/Am(III), are modeled by combining density functional theory with a generalized Anderson impurity model that accounts for the strong correlations between the 5f electrons. Diagonalization of the Anderson impurity model yields improved estimates for the redox potentials and the propensity of the actinide complexes to disproportionate.

  13. Stability of tetravalent actinides in perovskites

    SciTech Connect

    Williams, C.W.; Morss, L.R.; Choi, I.K.

    1983-01-01

    This paper reports the first determination of the enthalpy of formation of a complex actinide(IV) oxide: ..delta..H/sup 0//sub f/ (BaUO/sub 3/, s, 298 K) = -1690 +- 10 kJ mol/sup -1/. The preparation and properties of this and other actinide(IV) complex oxides are described and are compared with other perovskites BaMO/sub 3/. The relative stabilities of tetravalent and hexavalent uranium in various environments are compared in terms of the oxidation-reduction behavior of uranium in geological nuclear waste storage media; in perovskite, uranium(IV) is very unstable in comparison with uranium(VI).

  14. Systematization of actinides using cluster analysis

    SciTech Connect

    Kopyrin, A.A.; Terent`eva, T.N.; Khramov, N.N.

    1994-11-01

    A representation of the actinides in multidimensional property space is proposed for systematization of these elements using cluster analysis. Literature data for their atomic properties are used. Owing to the wide variation of published ionization potentials, medians are used to estimate them. Vertical dendograms are used for classification on the basis of distances between the actinides in atomic-property space. The properties of actinium and lawrencium are furthest removed from the main group. Thorium and mendelevium exhibit individualized properties. A cluster based on the einsteinium-fermium pair is joined by californium.

  15. Preparation of actinide-metal research

    SciTech Connect

    Aaron, W.S.; Culpepper, C.A.; Campbell, K.B.

    1986-01-01

    The preparation of actinide-metal research materials is one of many functions of the Isotope Research Materials Laboratory (IRML) at Oak Ridge National Lab. Research samples of uranium, plutonium, americium, and curium, typically from milligram quantities up to approx. 100 g, are prepared as pure metals or alloys to customer specifications. Larger quantities, up to many kilograms, of the lower activity actinides, such as /sup 235/U, /sup 238/U, and /sup 232/Th, are also fabricated into custom research forms. Physical forms of these metals include rolled foils or sheets, castings (ingot, rod, or special shapes), and evaporated or sputtered films.

  16. Spin-orbit coupling in actinide cations

    NASA Astrophysics Data System (ADS)

    Bagus, Paul S.; Ilton, Eugene S.; Martin, Richard L.; Jensen, Hans Jørgen Aa.; Knecht, Stefan

    2012-09-01

    The limiting case of Russell-Saunders coupling, which leads to a maximum spin alignment for the open shell electrons, usually explains the properties of high spin ionic crystals with transition metals. For actinide compounds, the spin-orbit splitting is large enough to cause a significantly reduced spin alignment. Novel concepts are used to explain the dependence of the spin alignment on the 5f shell occupation. We present evidence that the XPS of ionic actinide materials may provide direct information about the angular momentum coupling within the 5f shell.

  17. Ethnic Minorities and Telecommunications.

    ERIC Educational Resources Information Center

    Hayes-Hull, Marion

    Developments in communications technology should become a major concern of minorities (native Americans and Americans of African, Asian, and Hispanic racial or ethnic origin). Although minorities are disillusioned with broadcast television because television decision makers have not been sensitive to minority needs, they have shown interest…

  18. Alcohol and Minority Youth.

    ERIC Educational Resources Information Center

    Wright, Roosevelt, Jr.; Watts, Thomas D.

    1991-01-01

    Maintains that minority youth who use (or abuse) alcohol in American society deal with using alcohol, being minority, and being young, three dimensions viewed by society with mixed, sometimes hostile and/or fearful reactions. Suggests that examining alcoholism among minority youth involves coming to grips with poverty, education, income, and life…

  19. An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses: Criticality (keff) Predictions

    DOE PAGESBeta

    Scaglione, John M.; Mueller, Don E.; Wagner, John C.

    2014-12-01

    One of the most important remaining challenges associated with expanded implementation of burnup credit in the United States is the validation of depletion and criticality calculations used in the safety evaluation—in particular, the availability and use of applicable measured data to support validation, especially for fission products (FPs). Applicants and regulatory reviewers have been constrained by both a scarcity of data and a lack of clear technical basis or approach for use of the data. In this study, this paper describes a validation approach for commercial spent nuclear fuel (SNF) criticality safety (keff) evaluations based on best-available data and methodsmore » and applies the approach for representative SNF storage and transport configurations/conditions to demonstrate its usage and applicability, as well as to provide reference bias results. The criticality validation approach utilizes not only available laboratory critical experiment (LCE) data from the International Handbook of Evaluated Criticality Safety Benchmark Experiments and the French Haut Taux de Combustion program to support validation of the principal actinides but also calculated sensitivities, nuclear data uncertainties, and limited available FP LCE data to predict and verify individual biases for relevant minor actinides and FPs. The results demonstrate that (a) sufficient critical experiment data exist to adequately validate keff calculations via conventional validation approaches for the primary actinides, (b) sensitivity-based critical experiment selection is more appropriate for generating accurate application model bias and uncertainty, and (c) calculated sensitivities and nuclear data uncertainties can be used for generating conservative estimates of bias for minor actinides and FPs. Results based on the SCALE 6.1 and the ENDF/B-VII.0 cross-section libraries indicate that a conservative estimate of the bias for the minor actinides and FPs is 1.5% of their worth within the

  20. ESTIMATING IMPURITIES IN SURPLUS PLUTONIUM FOR DISPOSITION

    SciTech Connect

    Allender, J.; Moore, E.

    2013-07-17

    The United States holds at least 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. The Savannah River National Laboratory (SRNL) operates a Feed Characterization program for the Office of Fissile Materials Disposition of the National Nuclear Security Administration and the DOE Office of Environmental Management. Many of the items that require disposition are only partially characterized, and SRNL uses a variety of techniques to predict the isotopic and chemical properties that are important for processing through the Mixed Oxide Fuel Fabrication Facility and alternative disposition paths. Recent advances in laboratory tools, including Prompt Gamma Analysis and Peroxide Fusion treatment, provide data on the existing inventories that will enable disposition without additional, costly sampling and destructive analysis.

  1. Photonuclear reactions of actinide and pre-actinide nuclei at intermediate energies

    SciTech Connect

    Mukhopadhyay, Tapan; Basu, D. N.

    2007-12-15

    Photonuclear reaction is described with an approach based on the quasideuteron nuclear photoabsorption model followed by the process of competition between light particle evaporation and fission for the excited nucleus. Thus fission process is considered as a decay mode. The evaporation-fission process of the compound nucleus is simulated in a Monte Carlo framework. Photofission reaction cross sections are analysed in a systematic manner in the energy range {approx}50-70 MeV for the actinides {sup 232}Th, {sup 233}U, {sup 235}U, {sup 238}U, and {sup 237}Np and the pre-actinide nuclei {sup 208}Pb and {sup 209}Bi. The study reproduces satisfactorily well the available experimental data of photofission cross sections at energies {approx}50-70 MeV and the increasing trend of nuclear fissility with the fissility parameter Z{sup 2}/A for the actinides and pre-actinides at intermediate energies ({approx}20-140 MeV)

  2. Trends in actinide processing at Hanford

    SciTech Connect

    Harmon, H.D.

    1993-09-01

    In 1989, the mission at the Hanford Site began a dramatic and sometimes painful transition. The days of production--as we used to know it--are over. Our mission officially has become waste management and environmental cleanup. This mission change didn`t eliminate many jobs--in fact, budgets have grown dramatically to support the new mission. Most all of the same skilled crafts, engineers, and scientists are still required for the new mission. This change has not eliminated the need for actinide processing, but it has certainly changed the focus that our actinide chemists and process engineers have. The focus used to be on such things as increasing capacity, improving separations efficiency, and product purity. Minimizing waste had become a more important theme in recent years and it is still a very important concept in the waste management and environmental cleanup arena. However, at Hanford, a new set of words dominates the actinide process scene as we work to deal with actinides that still reside in a variety of forms at the Hanford Site. These words are repackage, stabilize, remove, store and dispose. Some key activities in each of these areas are described in this report.

  3. Optical properties of actinide and lanthanide ions

    SciTech Connect

    Hessler, J.P.; Carnall, W.T.

    1980-01-01

    This paper reviews some of the recent developments in this area of spectroscopy, emphasizing the optical properties of the tripositive lanthanide and actinide ions. In particular, the single ion properties of line positon, intensity, width, and fluorescence lifetime are discussed. 53 reference, 3 figures, 4 tables.

  4. Actinide valences in xenotime and monazite

    NASA Astrophysics Data System (ADS)

    Vance, E. R.; Zhang, Y.; McLeod, T.; Davis, J.

    2011-02-01

    Tetravalent U, Np and Pu can be substituted by ceramic methods into the rare earth site of xenotime and monazite in air atmospheres using Ca ions as charge compensators, while no evidence of penta- or hexavalent actinide ions was found. Some Pu 3+ and Np 3+ can be incorporated in xenotime samples fired in a reducing atmosphere.

  5. Rapid determination of actinides in asphalt samples

    SciTech Connect

    Maxwell, Sherrod L.; Culligan, Brian K.; Hutchison, Jay B.

    2014-01-12

    A new rapid method for the determination of actinides in asphalt samples has been developed that can be used in emergency response situations or for routine analysis If a radiological dispersive device (RDD), Improvised Nuclear Device (IND) or a nuclear accident such as the accident at the Fukushima Nuclear Power Plant in March, 2011 occurs, there will be an urgent need for rapid analyses of many different environmental matrices, including asphalt materials, to support dose mitigation and environmental clean up. The new method for the determination of actinides in asphalt utilizes a rapid furnace step to destroy bitumen and organics present in the asphalt and sodium hydroxide fusion to digest the remaining sample. Sample preconcentration steps are used to collect the actinides and a new stacked TRU Resin + DGA Resin column method is employed to separate the actinide isotopes in the asphalt samples. The TRU Resin plus DGA Resin separation approach, which allows sequential separation of plutonium, uranium, americium and curium isotopes in asphalt samples, can be applied to soil samples as well.

  6. COMPLEXANTS FOR ACTINIDE ELEMENT COORDINATION AND IMMOBILIZATION

    EPA Science Inventory

    We propose that inorganic clusters known as polyoxoanions (POAs) can be exploited as complexants for actinide (An) ion coordination and immobilization. Our objective is to develop rugged, stoichiometrically well-defined POAs that act as molecular containers of An elements. Poly...

  7. Actinide measurements by AMS using fluoride matrices

    NASA Astrophysics Data System (ADS)

    Cornett, R. J.; Kazi, Z. H.; Zhao, X.-L.; Chartrand, M. G.; Charles, R. J.; Kieser, W. E.

    2015-10-01

    Actinides can be measured by alpha spectroscopy (AS), mass spectroscopy or accelerator mass spectrometry (AMS). We tested a simple method to separate Pu and Am isotopes from the sample matrix using a single extraction chromatography column. The actinides in the column eluent were then measured by AS or AMS using a fluoride target matrix. Pu and Am were coprecipitated with NdF3. The strongest AMS beams of Pu and Am were produced when there was a large excess of fluoride donor atoms in the target and the NdF3 precipitates were diluted about 6-8 fold with PbF2. The measured concentrations of 239,240Pu and 241Am agreed with the concentrations in standards of known activity and with two IAEA certified reference materials. Measurements of 239,240Pu and 241Am made at A.E. Lalonde AMS Laboratory agree, within their statistical uncertainty, with independent measurements made using the IsoTrace AMS system. This work demonstrated that fluoride targets can produce reliable beams of actinide anions and that the measurement of actinides using fluorides agree with published values in certified reference materials.

  8. Rapid determination of actinides in asphalt samples

    DOE PAGESBeta

    Maxwell, Sherrod L.; Culligan, Brian K.; Hutchison, Jay B.

    2014-01-12

    A new rapid method for the determination of actinides in asphalt samples has been developed that can be used in emergency response situations or for routine analysis If a radiological dispersive device (RDD), Improvised Nuclear Device (IND) or a nuclear accident such as the accident at the Fukushima Nuclear Power Plant in March, 2011 occurs, there will be an urgent need for rapid analyses of many different environmental matrices, including asphalt materials, to support dose mitigation and environmental clean up. The new method for the determination of actinides in asphalt utilizes a rapid furnace step to destroy bitumen and organicsmore » present in the asphalt and sodium hydroxide fusion to digest the remaining sample. Sample preconcentration steps are used to collect the actinides and a new stacked TRU Resin + DGA Resin column method is employed to separate the actinide isotopes in the asphalt samples. The TRU Resin plus DGA Resin separation approach, which allows sequential separation of plutonium, uranium, americium and curium isotopes in asphalt samples, can be applied to soil samples as well.« less

  9. Cross sections for actinide burner reactors

    SciTech Connect

    Difilippo, F.C.

    1991-01-01

    Recent studies have shown the feasibility of burning higher actinides (i.e., transuranium (TRU) elements excluding plutonium) in ad hoc designed reactors (Actinide Burner Reactors: ABR) which, because of their hard neutron spectra, enhance the fission of TRU. The transmutation of long-lived radionuclides into stable or short-lived isotopes reduces considerably the burden of handling high-level waste from either LWR or Fast Breeder Reactors (FBR) fuels. Because of the large concentrations of higher actinides in these novel reactor designs the Doppler effect due to TRU materials is the most important temperature coefficient from the point of view of reactor safety. Here we report calculations of energy group-averaged capture and fission cross sections as function of temperature and dilution for higher actinides in the resolved and unresolved resonance regions. The calculations were done with the codes SAMMY in the resolved region and URR in the unresolved regions and compared with an independent calculation. 4 refs., 2 figs., 2 tabs.

  10. Environmental Impact of the Nuclear Fuel Cycle: Fate of Actinides

    SciTech Connect

    Ewing, Rodney C.; Runde, W.; Albrecht-Schmitt, Thomas E.

    2011-01-31

    The resurgence of nuclear power as a strategy for reducing greenhouse gas (GHG) emissions has, in parallel, revived interest in the environmental impact of actinides. Just as GHG emissions are the main environmental impact of the combustion of fossil fuels, the fate of actinides, consumed and produced by nuclear reactions, determines whether nuclear power is viewed as an environmentally “friendly” source of energy. In this article, we summarize the sources of actinides in the nuclear fuel cycle, how actinides are separated by chemical processing, the development of actinide-bearing materials, and the behavior of actinides in the environment. At each stage, actinides present a unique and complicated behavior because of the 5f electronic configurations.

  11. Review Article: The Effects of Radiation Chemistry on Solvent Extraction 3: A Review of Actinide and Lanthanide Extraction

    SciTech Connect

    Bruce J. Mincher; Giuseppe Modolo; Stephen P. Mezyk

    2009-12-01

    The partitioning of the long-lived ?-emitters and the high-yield fission products from dissolved nuclear fuel is a key component of processes envisioned for the safe recycling of nuclear fuel and the disposition of high-level waste. These future processes will likely be based on aqueous solvent extraction technologies for light water reactor fuel and consist of four main components for the sequential separation of uranium, fission products, group trivalent actinides and lanthanides, and then trivalent actinides from lanthanides. Since the solvent systems will be in contact with highly radioactive solutions, they must be robust toward radiolytic degradation in an irradiated mixed organic, aqueous acidic environment. Therefore, an understanding of their radiation chemistry is important to the design of a practical system. In the first paper in this series we reviewed the radiation chemistry of irradiated aqueous nitric acid and the tributyl phosphate ligand for uranium extraction in the first step of these extractions. In the second, we reviewed the radiation chemistry of the ligands proposed for use in the extraction of cesium and strontium fission products. Here, we review the radiation chemistry of the ligands that might be used in the third step in the series of separations, for the group extraction of the lanthanides and actinides. This includes traditional organophosphorous reagents such as CMPO and HDEHP, as well as novel reagents such as the amides and diamides currently being investigated.

  12. Dispositions as Virtues: The Complexity of the Construct

    ERIC Educational Resources Information Center

    Sockett, Hugh

    2009-01-01

    The value of conceptualizing the desirable dispositions of the teacher as virtues is illuminated through distinguishing such dispositions-as-virtues from other dispositions and from personality traits. Dispositions as virtues are qualities achieved by the individual's initiative, in the face of obstacles, and are intrinsically motivated. The…

  13. LLNL MOX fuel lead assemblies data report for the surplus plutonium disposition environmental impact statement

    SciTech Connect

    O`Connor, D.G.; Fisher, S.E.; Holdaway, R.

    1998-08-01

    The purpose of this document is to support the US Department of Energy (DOE) Fissile Materials Disposition Program`s preparation of the draft surplus plutonium disposition environmental impact statement. This is one of several responses to data call requests for background information on activities associated with the operation of the lead assembly (LA) mixed-oxide (MOX) fuel fabrication facility. The DOE Office of Fissile Materials Disposition (DOE-MD) has developed a dual-path strategy for disposition of surplus weapons-grade plutonium. One of the paths is to disposition surplus plutonium through irradiation of MOX fuel in commercial nuclear reactors. MOX fuel consists of plutonium and uranium oxides (PuO{sub 2} and UO{sub 2}), typically containing 95% or more UO{sub 2}. DOE-MD requested that the DOE Site Operations Offices nominate DOE sites that meet established minimum requirements that could produce MOX LAs. LLNL has proposed an LA MOX fuel fabrication approach that would be done entirely inside an S and S Category 1 area. This includes receipt and storage of PuO{sub 2} powder, fabrication of MOX fuel pellets, assembly of fuel rods and bundles, and shipping of the packaged fuel to a commercial reactor site. Support activities will take place within a Category 1 area. Building 332 will be used to receive and store the bulk PuO{sub 2} powder, fabricate MOX fuel pellets, and assemble fuel rods. Building 334 will be used to assemble, store, and ship fuel bundles. Only minor modifications would be required of Building 332. Uncontaminated glove boxes would need to be removed, petition walls would need to be removed, and minor modifications to the ventilation system would be required.

  14. Proliferation resistance criteria for fissile material disposition

    SciTech Connect

    Close, D.A.; Fearey, B.L.; Markin, J.T.; Rutherford, D.A.; Duggan, R.A.; Jaeger, C.D.; Mangan, D.L.; Moya, R.W.; Moore, L.R.; Strait, R.S.

    1995-04-01

    The 1994 National Academy of Sciences study {open_quotes}Management and Disposition of Excess Weapons Plutonium{close_quotes} defined options for reducing the national and international proliferation risks of materials declared excess to the nuclear weapons program. This report proposes criteria for assessing the proliferation resistance of these options. The criteria are general, encompassing all stages of the disposition process from storage through intermediate processing to final disposition including the facilities, processing technologies and materials, the level of safeguards for these materials, and the national/subnational threat to the materials.

  15. Conjugates of Magnetic Nanoparticle -- Actinide Specific Chelator for Radioactive Waste Separation

    SciTech Connect

    Maninder Kaur; Huijin Zhang; Leigh Martin; Terry Todd; You Qiang

    2013-11-01

    A novel nanotechnology for the separation of radioactive waste that uses magnetic nanoparticles (MNPs) conjugated with actinide specific chelators (MNP-Che) is reviewed with a focus on design and process development. The MNP-Che separation process is an effective way of separating heat generating minor actinides (Np, Am, Cm) from spent nuclear fuel solution to reduce the radiological hazard. It utilizes coated MNPs to selectively adsorb the contaminants onto their surfaces, after which the loaded particles are collected using a magnetic field. The MNP-Che conjugates can be recycled by stripping contaminates into a separate, smaller volume of solution, and then become the final waste form for disposal after reusing number of times. Due to the highly selective chelators, this remediation method could be both simple and versatile while allowing the valuable actinides to be recovered and recycled. Key issues standing in the way of large-scale application are stability of the conjugates and their dispersion in solution to maintain their unique properties, especially large surface area, of MNPs. With substantial research progress made on MNPs and their surface functionalization, as well as development of environmentally benign chelators, this method could become very flexible and cost-effective for recycling used fuel. Finally, the development of this nanotechnology is summarized and its future direction is discussed.

  16. QUANTIFICATION OF ACTINIDE ALPHA-RADIATION DAMAGE IN MINERALS AND CERAMICS

    SciTech Connect

    Farnan, Ian E.; Cho, Herman M.; Weber, William J.

    2007-01-11

    There are large amounts of heavy alpha-emitters in nuclear waste and nuclear materials inventories stored in various sites around the world. These include plutonium and minor actinides such as americium and curium. In preparation for geological disposal there is a consensus that actinides that have been separated from spent nuclear fuel should be immobilised within mineral-based ceramics rather than glass. Over the long-term, the alpha-decay taking place in these ceramics will severely disrupt their crystalline structure and reduce their durability. A fundamental property in predicting cumulative radiation damage is the number of atoms permanently displaced per alpha–decay. Currently, this number is estimated as 1000-2000 atoms/alpha decay event. Here, we report nuclear magnetic resonance, spin-counting experiments that measure close to 5000 atoms/alpha decay event in radiation damaged natural zircons. New radiological NMR measurements on highly radioactive, 239Pu zircon show damage similar to that created by 238U and 232Th in mineral zircons at the same dose, indicating no significant effect of dose rate. Based on these measurements, the initially crystalline structure of a 10 wt% 239Pu zircon would be amorphous after only 1400 years in a geological repository. These measurements establish a basis for assessing the long-term structural durability of actinide-containing ceramics based on an atomistic understanding of the fundamental damage event.

  17. Synthesis of actinide nitrides, phosphides, sulfides and oxides

    DOEpatents

    Van Der Sluys, William G.; Burns, Carol J.; Smith, David C.

    1992-01-01

    A process of preparing an actinide compound of the formula An.sub.x Z.sub.y wherein An is an actinide metal atom selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, x is selected from the group consisting of one, two or three, Z is a main group element atom selected from the group consisting of nitrogen, phosphorus, oxygen and sulfur and y is selected from the group consisting of one, two, three or four, by admixing an actinide organometallic precursor wherein said actinide is selected from the group consisting of thorium, uranium, plutonium, neptunium, and americium, a suitable solvent and a protic Lewis base selected from the group consisting of ammonia, phosphine, hydrogen sulfide and water, at temperatures and for time sufficient to form an intermediate actinide complex, heating said intermediate actinide complex at temperatures and for time sufficient to form the actinide compound, and a process of depositing a thin film of such an actinide compound, e.g., uranium mononitride, by subliming an actinide organometallic precursor, e.g., a uranium amide precursor, in the presence of an effectgive amount of a protic Lewis base, e.g., ammonia, within a reactor at temperatures and for time sufficient to form a thin film of the actinide compound, are disclosed.

  18. Sample preparation for actinide solid state research

    NASA Astrophysics Data System (ADS)

    Spirlet, J. C.

    1982-09-01

    The actinide elements (5f elements) and their compounds constitute a very interesting group for solid state research. The electronic properties of the 5f elements show intermediate behavior between the well-understood, completely localized 4f system (lanthanides) and the 3d system (transition elements). The possibility of understanding some unexplained properties of the 3d elements through a systematic investigation of the electronic structures of the actinides considerably increased interest in samples with well-defined composition and structure and with well-known purity. In some cases, single crystals of low defect densities and high purity levels are needed to allow sophisticated investigations of physical properties. Actinide compounds are easily obtained at a high purity level by direct synthesis from pure elements using noncontaminating techniques. Examples of these techniques are the reaction of the actinide metal powder with the vapor of an oxidant in a sealed quartz ampoule, leviation melting on a water-cooled pedestal or melting in a Huking crucible. Actinide metals are produced by metallothermic reduction of commercially available oxides or carbides or by the van Arkel purification process. The metals are refined to the desired purity level by evaporation in vacuum for the more volatile elements (Ac, Pu, Am, Cm, Bk) and by the van Arkel process for the metals with low vapor pressure. Single crystals of actinide compounds have been grown by chemical vapor transport methods (oxides, chalcogenides), high temperature solution growth techniques (oxides), and pulling from the melt by the Czochralski method (oxides, intermetallics). Thin solid films have been prepared by vacuum evaporation or by focused ion-beam sputtering. The materials are analyzed for trace-level impurity content by inductively-coupled plasma spectroscopy, by spark source mass spectroscopy and by secondary-ion mass spectroscopy. The chemical composition of the compounds is determined by

  19. Electrorecovery of actinides at room temperature

    SciTech Connect

    Stoll, Michael E; Oldham, Warren J; Costa, David A

    2008-01-01

    There are a large number of purification and processing operations involving actinide species that rely on high-temperature molten salts as the solvent medium. One such application is the electrorefining of impure actinide metals to provide high purity material for subsequent applications. There are some drawbacks to the electrodeposition of actinides in molten salts including relatively low yields, lack of accurate potential control, maintaining efficiency in a highly corrosive environment, and failed runs. With these issues in mind we have been investigating the electrodeposition of actinide metals, mainly uranium, from room temperature ionic liquids (RTILs) and relatively high-boiling organic solvents. The RTILs we have focused on are comprised of 1,3-dialkylimidazolium or quaternary ammonium cations and mainly the {sup -}N(SO{sub 2}CF{sub 3}){sub 2} anion [bis(trif1uoromethylsulfonyl)imide {equivalent_to} {sup -}NTf{sub 2}]. These materials represent a class of solvents that possess great potential for use in applications employing electrochemical procedures. In order to ascertain the feasibility of using RTILs for bulk electrodeposition of actinide metals our research team has been exploring the electron transfer behavior of simple coordination complexes of uranium dissolved in the RTIL solutions. More recently we have begun some fundamental electrochemical studies on the behavior of uranium and plutonium complexes in the organic solvents N-methylpyrrolidone (NMP) and dimethylsulfoxide (DMSO). Our most recent results concerning electrodeposition will be presented in this account. The electrochemical behavior of U(IV) and U(III) species in RTILs and the relatively low vapor pressure solvents NMP and DMSO is described. These studies have been ongoing in our laboratory to uncover conditions that will lead to the successful bulk electrodeposition of actinide metals at a working electrode surface at room temperature or slightly elevated temperatures. The RTILs we

  20. KE Basin water dispositioning engineering study

    SciTech Connect

    Hunacek, G.S.; Gahir, S.S.

    1994-09-23

    This engineering study is a feasibility study of KE Basin water treatment to an acceptable level and dispositioning the treated water to Columbia River, ground through ETF or to air through evaporation.

  1. Trivalent Lanthanide/Actinide Separation Using Aqueous-Modified TALSPEAK Chemistry

    SciTech Connect

    Travis S. Grimes; Richard D. Tillotson; Leigh R. Martin

    2014-05-01

    TALSPEAK is a liquid/liquid extraction process designed to separate trivalent lanthanides (Ln3+) from minor actinides (MAs) Am3+ and Cm3+. Traditional TALSPEAK organic phase is comprised of a monoacidic dialkyl bis(2-ethylhexyl)phosphoric acid extractant (HDEHP) in diisopropyl benzene (DIPB). The aqueous phase contains a soluble aminopolycarboxylate diethylenetriamine-N,N,N’,N”,N”-pentaacetic acid (DTPA) in a concentrated (1.0-2.0 M) lactic acid (HL) buffer with the aqueous acidity typically adjusted to pH 3.0. TALSPEAK balances the selective complexation of the actinides by DTPA against the electrostatic attraction of the lanthanides by the HDEHP extractant to achieve the desired trivalent lanthanide/actinide group separation. Although TALSPEAK is considered a successful separations scheme, recent fundamental studies have highlighted complex chemical interactions occurring in the aqueous and organic phases during the extraction process. Previous attempts to model the system have shown thermodynamic models do not accurately predict the observed extraction trends in the p[H+] range 2.5-4.8. In this study, the aqueous phase is modified by replacing the lactic acid buffer with a variety of simple and longer-chain amino acid buffers. The results show successful trivalent lanthanide/actinide group separation with the aqueous-modified TALSPEAK process at pH 2. The amino acid buffer concentrations were reduced to 0.5 M (at pH 2) and separations were performed without any effect on phase transfer kinetics. Successful modeling of the aqueous-modified TALSPEAK process (p[H+] 1.6-3.1) using a simplified thermodynamic model and an internally consistent set of thermodynamic data is presented.

  2. AQUEOUS ELECTROCHEMICAL MECHANISMS IN ACTINIDE RESIDUE PROCESSING

    EPA Science Inventory

    The United States Department of Energy is faced with the stabilization and disposition of hundreds of metric tons of plutonium - and uranium-bearing residue materials resulting from 50+ years of nuclear weapons production activities. These materials are presently in storage at si...

  3. A causal dispositional account of fitness.

    PubMed

    Triviño, Vanessa; Nuño de la Rosa, Laura

    2016-09-01

    The notion of fitness is usually equated to reproductive success. However, this actualist approach presents some difficulties, mainly the explanatory circularity problem, which have lead philosophers of biology to offer alternative definitions in which fitness and reproductive success are distinguished. In this paper, we argue  that none of these alternatives is satisfactory and, inspired by Mumford and Anjum's dispositional theory of causation, we offer a definition of fitness as a causal dispositional property. We argue that, under this framework, the distinctiveness that biologists usually attribute to fitness-namely, the fact that fitness is something different from both the physical traits of an organism and the number of offspring it leaves-can be explained, and the main problems associated with the concept of fitness can be solved. Firstly, we introduce Mumford and Anjum's dispositional theory of causation and present our definition of fitness as a causal disposition. We explain in detail each of the elements involved in our definition, namely: the relationship between fitness and the functional dispositions that compose it, the emergent character of fitness, and the context-sensitivity of fitness. Finally, we explain how fitness and realized fitness, as well as expected and realized fitness are distinguished in our approach to fitness as a causal disposition. PMID:27338570

  4. Model Minority Stereotype Reconsidered.

    ERIC Educational Resources Information Center

    Kobayashi, Futoshi

    This paper explores the origin and historical background of the "model minority" stereotype. It includes evidence illustrating problems resulting from the artificial grouping of Asian Americans as one ethnic group and the stereotype's influence on young Asian Americans. In the 1960s, the U.S. media began to portray the model minority through…

  5. Minorities in Higher Education.

    ERIC Educational Resources Information Center

    Justiz, Manuel J., Ed.; And Others

    This book presents 19 papers on efforts to increase the participation of members of minority groups in higher education. The papers are: (1) "Demographic Trends and the Challenges to American Higher Education" (Manuel Justiz); (2) "Three Realities: Minority Life in the United States--The Struggle for Economic Equity (adapted by Don M. Blandin);…

  6. Recruiting Minority Students.

    ERIC Educational Resources Information Center

    Reed, Bobette P.; Dandridge, William L.

    To help improve private schools' recruitment of minority students, this handbook discusses where and how to begin, recruitment strategies, applicant assessment, and the need for in-school support systems for minority students. The authors stress that each school should begin by analyzing its own objectives, attitudes, and admission program.…

  7. Gerontology Training for Minorities.

    ERIC Educational Resources Information Center

    Cho, Pill Jay

    The Grambling State University Minority Management Internship in Aging program described in this report was designed to provide internships to social work students to aid the minority elderly. The status of the elderly in the United States and the personnel and agencies that assist them are discussed in the following chapters: (1) "Introduction"…

  8. American Minorities in Astronomy.

    ERIC Educational Resources Information Center

    Price, Jill S.; Hafer, Abigail A.

    1995-01-01

    A collection of articles that address the question of why minorities are still underrepresented in science after years of civil rights legislation and affirmative action. A variety of programs aimed at increasing minorities and women in the field of astronomy and other sciences are discussed. Personal accounts are also provided. (LZ)

  9. Minority Achievement Report.

    ERIC Educational Resources Information Center

    Prince George's Community Coll., Largo, MD. Office of Institutional Research and Analysis.

    This report summarizes the achievements of Prince George's Community College (PGCC) with regard to minority outcomes. Table 1 summarizes the undergraduate enrollment trends for African Americans as well as total minorities from fall 1994 through fall 1998. Both the headcount number of African American students and the proportion of African…

  10. Actinide phosphonate complexes in aqueous solutions

    SciTech Connect

    Nash, K.L.

    1993-10-01

    Complexes formed by actinides with carboxylic acids, polycarboxylic acids, and aminopolycarboxylic acids play a central role in both the basic and process chemistry of the actinides. Recent studies of f-element complexes with phosphonic acid ligands indicate that new ligands incorporating doubly ionizable phosphonate groups (-PO{sub 3}H{sub 2}) have many properties which are unique chemically, and promise more efficient separation processes for waste cleanup and environmental restoration. Simple diphosphonate ligands form much stronger complexes than isostructural carboxylates, often exhibiting higher solubility as well. In this manuscript recent studies of the thermodynamics and kinetics of f-element complexation by 1,1 and 1,2 diphosphonic acid ligands are described.

  11. The local minority game

    NASA Astrophysics Data System (ADS)

    Moelbert, S.; De Los Rios, P.

    2002-01-01

    Ecologists and economists try to explain collective behavior in terms of competitive systems of selfish individuals with the ability to learn from the past. Statistical physicists have been investigating models which might contribute to the understanding of the underlying mechanisms of these systems. During the last 3 yr one intuitive model, commonly referred to as the minority game (MG), has attracted considerable attention. Powerful yet simple, the minority game has produced encouraging results which can explain the temporal behavior of competitive systems. Here we switch the interest to the phenomena due to a distribution of the individuals in space. For analyzing these effects we modify the minority game and the local minority game (LMG) is introduced. We study the system both numerically and analytically, using the customary techniques already developed for the ordinary Minority Game.

  12. In vitro removal of actinide (IV) ions

    DOEpatents

    Weitl, Frederick L.; Raymond, Kenneth N.

    1982-01-01

    A compound of the formula: ##STR1## wherein X is hydrogen or a conventional electron-withdrawing group, particularly --SO.sub.3 H or a salt thereof; n is 2, 3, or 4; m is 2, 3, or 4; and p is 2 or 3. The present compounds are useful as specific sequestering agents for actinide (IV) ions. Also described is a method for the 2,3-dihydroxybenzamidation of azaalkanes.

  13. Separation of Californium from other Actinides

    DOEpatents

    Mailen, J C; Ferris, L M

    1973-09-25

    A method is provided for separating californium from a fused fluoride composition containing californium and at least one element selected from the group consisting of plutonium, americium, curium, uranium, thorium, and protactinium which comprises contacting said fluoride composition with a liquid bismuth phase containing sufficient lithium or thorium to effect transfer of said actinides to the bismuth phase and then contacting the liquid bismuth phase with molten LiCl to effect selective transfer of californium to the chloride phase.

  14. Surrogate Reactions in the Actinide Region

    SciTech Connect

    Burke, J T; Bernstein, L A; Scielzo, N D; Bleuel, D L; Lesher, S R; Escher, J; Ahle, L; Dietrich, F S; Hoffman, R D; Norman, E B; Sheets, S A; Phair, L; Fallon, P; Clark, R M; Gibelin, J; Jewett, C; Lee, I Y; Macchiavelli, A O; McMahan, M A; Moretto, L G; Rodriguez-Vieitez, E; Wiedeking, M; Lyles, B F; Beausang, C W; Allmond, J M; Ai, H; Cizewski, J A; Hatarik, R; O'Malley, P D; Swan, T

    2008-01-30

    Over the past three years we have studied various surrogate reactions (d,p), ({sup 3}He,t), ({alpha},{alpha}{prime}) on several uranium isotopes {sup 234}U, {sup 235}U, {sup 236}U, and {sup 238}U. An overview of the STARS/LIBERACE surrogate research program as it pertains to the actinides is discussed. A summary of results to date will be presented along with a discussion of experimental difficulties encountered in surrogate experiments and future research directions.

  15. On the valence fluctuation in the early actinide metals

    DOE PAGESBeta

    Soderlind, P.; Landa, A.; Tobin, J. G.; Allen, P.; Medling, S.; Booth, C. H.; Bauer, E. D.; Cooley, J. C.; Sokaras, D.; Weng, T. -C.; et al

    2015-12-15

    In this study, recent X-ray measurements suggest a degree of valence fluctuation in plutonium and uranium intermetallics. We are applying a novel scheme, in conjunction with density functional theory, to predict 5f configuration fractions of states with valence fluctuations for the early actinide metals. For this purpose we perform constrained integer f-occupation calculations for the α phases of uranium, neptunium, and plutonium metals. For plutonium we also investigate the δ phase. The model predicts uranium and neptunium to be dominated by the f3 and f4 configurations, respectively, with only minor contributions from other configurations. For plutonium (both α and δmore » phase) the scenario is dramatically different. Here, the calculations predict a relatively even distribution between three valence configurations. The δ phase has a greater configuration fraction of f6 compared to that of the α phase. The theory is consistent with the interpretations of modern X-ray experiments and we present resonant X-ray emission spectroscopy results for α-uranium.« less

  16. On the valence fluctuation in the early actinide metals

    SciTech Connect

    Soderlind, P.; Landa, A.; Tobin, J. G.; Allen, P.; Medling, S.; Booth, C. H.; Bauer, E. D.; Cooley, J. C.; Sokaras, D.; Weng, T. -C.; Nordlund, D.

    2015-12-15

    In this study, recent X-ray measurements suggest a degree of valence fluctuation in plutonium and uranium intermetallics. We are applying a novel scheme, in conjunction with density functional theory, to predict 5f configuration fractions of states with valence fluctuations for the early actinide metals. For this purpose we perform constrained integer f-occupation calculations for the α phases of uranium, neptunium, and plutonium metals. For plutonium we also investigate the δ phase. The model predicts uranium and neptunium to be dominated by the f3 and f4 configurations, respectively, with only minor contributions from other configurations. For plutonium (both α and δ phase) the scenario is dramatically different. Here, the calculations predict a relatively even distribution between three valence configurations. The δ phase has a greater configuration fraction of f6 compared to that of the α phase. The theory is consistent with the interpretations of modern X-ray experiments and we present resonant X-ray emission spectroscopy results for α-uranium.

  17. Actinide behavior in a freshwater pond

    SciTech Connect

    Trabalka, J.R.; Bogle, M.A.; Scott, T.G.

    1983-01-01

    Long-term investigations of solution chemistry in an alkaline freshwater pond have revealed that actinide oxidation state behavior, particularly that of plutonium, is complex. The Pu(V,VI) fraction was predominant in solution, but it varied over the entire range reported from other natural aquatic environments, in this case, as a result of intrinsic biological and chemical cycles (redox and pH-dependent phenomena). A strong positive correlation between plutonium (Pu), but not uranium (U), and hydroxyl ion over the observation period, especially when both were known to be in higher oxidation states, was particularly notable. Coupled with other examples of divergent U and Pu behavior, this result suggests that Pu(V), or perhaps a mixture of Pu(V,VI), was the prevalent oxidation state in solution. Observations of trivalent actinide sorption behavior during an algal bloom, coupled with the association with a high-molecular weight (nominally 6000 to 10,000 mol wt) organic fraction in solution, indicate that solution-detritus cycling of organic carbon, in turn, may be the primary mechanism in amercium-curium (Am-Cm) cycling. Sorption by sedimentary materials appears to predominate over other factors controlling effective actinide solubility and may explain, at least partially, the absence of an expected strong positive correlation between carbonate and dissolved U. 49 references, 6 figures, 12 tables.

  18. SAMPLE RESULTS FROM THE INTERIM SALT DISPOSITION PROGRAM MACROBATCH 8 TANK 21H QUALIFICATION SAMPLES

    SciTech Connect

    Peters, T. B.; Washington, A. L.

    2015-01-13

    Savannah River National Laboratory (SRNL) analyzed samples from Tank 21H in support of qualification of Macrobatch (Salt Batch) 8 for the Interim Salt Disposition Program (ISDP). An Actinide Removal Process (ARP) and several Extraction-Scrub- Strip (ESS) tests were also performed. This document reports characterization data on the samples of Tank 21H as well as simulated performance of ARP and the Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU). No issues with the projected Salt Batch 8 strategy are identified. A demonstration of the monosodium titanate (MST) (0.2 g/L) removal of strontium and actinides provided acceptable average decontamination factors for plutonium of 2.62 (4 hour) and 2.90 (8 hour); and average strontium decontamination factors of 21.7 (4 hour) and 21.3 (8 hour). These values are consistent with results from previous salt batch ARP tests. The two ESS tests also showed acceptable performance with extraction distribution ratios (D{sub (Cs)}) values of 52.5 and 50.4 for the Next Generation Solvent (NGS) blend (from MCU) and NGS (lab prepared), respectively. These values are consistent with results from previous salt batch ESS tests. Even though the performance is acceptable, SRNL recommends that a model for predicting extraction behavior for cesium removal for the blended solvent and NGS be developed in order to improve our predictive capabilities for the ESS tests.

  19. Recovery of actinides from actinide-aluminium alloys by chlorination: Part II

    NASA Astrophysics Data System (ADS)

    Souček, P.; Cassayre, L.; Eloirdi, R.; Malmbeck, R.; Meier, R.; Nourry, C.; Claux, B.; Glatz, J.-P.

    2014-04-01

    A chlorination route is being investigated for recovery of actinides from actinide-aluminium alloys, which originate from pyrochemical recovery of actinides from spent metallic nuclear fuel by electrochemical methods in molten LiCl-KCl. In the present work, the most important steps of this route were experimentally tested using U-Pu-Al alloy prepared by electrodeposition of U and Pu on solid aluminium plate electrodes. The investigated processes were vacuum distillation for removal of the salt adhered on the electrode, chlorination of the alloy by chlorine gas and sublimation of the AlCl3 formed. The processes parameters were set on the base of a previous thermochemical study and an experimental work using pure UAl3 alloy. The present experimental results indicated high efficiency of salt distillation and chlorination steps, while the sublimation step should be further optimised.

  20. Bidentate organophosphorus solvent extraction process for actinide recovery and partition

    DOEpatents

    Schulz, Wallace W.

    1976-01-01

    A liquid-liquid extraction process for the recovery and partitioning of actinide values from acidic nuclear waste aqueous solutions, the actinide values including trivalent, tetravalent and hexavalent oxidation states is provided and includes the steps of contacting the aqueous solution with a bidentate organophosphorous extractant to extract essentially all of the actinide values into the organic phase. Thereafter the respective actinide fractions are selectively partitioned into separate aqueous solutions by contact with dilute nitric or nitric-hydrofluoric acid solutions. The hexavalent uranium is finally removed from the organic phase by contact with a dilute sodium carbonate solution.

  1. Advanced Aqueous Separation Systems for Actinide Partitioning

    SciTech Connect

    Nash, Ken; Martin, Leigh; Lumetta, Gregg

    2015-04-02

    One of the most challenging aspects of advanced processing of used nuclear fuel is the separation of transplutonium actinides from fission product lanthanides. This separation is essential if actinide transmutation options are to be pursued in advanced fuel cycles, as lanthanides compete with actinides for neutrons in both thermal and fast reactors, thus limiting efficiency. The separation is difficult because the chemistry of Am3+ and Cm3+ is nearly identical to that of the trivalent lanthanides (Ln3+). The prior literature teaches that two approaches offer the greatest probability of devising a successful group separation process based on aqueous processes: 1) the application of complexing agents containing ligand donor atoms that are softer than oxygen (N, S, Cl-) or 2) changing the oxidation state of Am to the IV, V, or VI state to increase the essential differences between Am and lanthanide chemistry (an approach utilized in the PUREX process to selectively remove Pu4+ and UO22+ from fission products). The latter approach offers the additional benefit of enabling a separation of Am from Cm, as Cm(III) is resistant to oxidation and so can easily be made to follow the lanthanides. The fundamental limitations of these approaches are that 1) the soft(er) donor atoms that interact more strongly with actinide cations than lanthanides form substantially weaker bonds than oxygen atoms, thus necessitating modification of extraction conditions for adequate phase transfer efficiency, 2) soft donor reagents have been seen to suffer slow phase transfer kinetics and hydro-/radiolytic stability limitations and 3) the upper oxidation states of Am are all moderately strong oxidants, hence of only transient stability in media representative of conventional aqueous separations systems. There are examples in the literature of both approaches having been described. However, it is not clear at present that any extant process is sufficiently robust for application at the scale

  2. The color of juvenile justice: racial disparities in dispositional decisions.

    PubMed

    Fader, Jamie J; Kurlychek, Megan C; Morgan, Kirstin A

    2014-03-01

    Existing research on dispositional decisions typically models the outcome as merely placed or not placed. However, this does not accurately reflect the wide variation in residential options available to juvenile court actors. In this research, we combine data from ProDES, which tracks adjudicated youth in Philadelphia, with data from the Program Design Inventory, which describes over 100 intervention programs, to further examine the factors that influence court actors' decision making in selecting an appropriate program for a juvenile offender. We find that even after controlling for legal and needs-based factors, race continues to exert a significant influence, with decision makers being significantly more likely to commit minority youth to facilities using physical regimen as their primary modality and reserving smaller, therapeutic facilities for their white counterparts. Using focal concerns theory as an explanatory lens, we suggest that court actors in this jurisdiction employ a racialized perceptual shorthand of youthful offenders that attributes both higher levels of blame and lower evaluations of reformability to minority youth. PMID:24468439

  3. Propranolol disposition in renal failure.

    PubMed Central

    Wood, A J; Vestal, R E; Spannuth, C L; Stone, W J; Wilkinson, G R; Shand, D G

    1980-01-01

    1 Previous studies of propranolol disposition in renal failure have been conflicting. 2 Using simultaneous administration of [3H]-propranolol intravenously and unlabelled propranolol orally the principal determinants of drug distribution were calculated in normals, patients with severe renal impairment (creatinine clearance 14.5 +/- 2.8 ml/min) but not on haemodialysis and patients on haemodialysis (creatinine clearance less than 5 ml/min). 3 The effect of haemodialysis on propranolol binding and free fraction was also examined. The percentage of propranolol unbound rose from 7.1% to 9.9%. (P less than 0.001) 20 min following heparinization and beginning haemodialysis. This was accompanied by a large rise in free fatty acids from 0.567 +/- 0.059 to 3.326 +/- 0.691 mumol/ml (P less than 0.005). 4 The blood to plasma concentration ratios of propranolol were significantly higher in patients with renal failure (P less than 0.02) and on haemodialysis (P less than 0.001) and were significantly negatively correlated (P less than 0.001) with the haematocrit. 5 Although the half-life propranolol was significantly shortened in the patients with renal failure (P less than 0.02), there was no change in the apparent liver blood flow, extraction ratio or the principal determinants of steady-state drug concentrations in blood namely oral and intravenous clearance from blood. 6 There is, therefore, no pharmacokinetic basis to adjust the dosage of propranolol in patients with renal failure. PMID:7470370

  4. Drug disposition in cystic fibrosis.

    PubMed

    Rey, E; Tréluyer, J M; Pons, G

    1998-10-01

    There are many pathological changes in patients with cystic fibrosis (CF) which can lead to alterations in drug disposition. Although, in patients with CF, the extent of drug absorption varies widely and the rate of absorption is slower, bioavailability is not altered. Plasma protein binding for the majority of drugs studied did not differ in patients with CF compared with control groups. The difference in volume of distribution of most drugs between patients with CF and healthy individuals vanished when corrected for lean body mass. Despite hepatic dysfunction, patients with CF have enhanced clearance of many, but not all, drugs. Phase I mixed-function oxidases are selectively affected: cytochrome P450 (CYP) 1A2 and CYP2C8 have enhanced activity, while other CYP isoforms such as CYP2C9 and CYP3A4 are unaffected. Increased phase II activities are also demonstrated: glucuronyl transferase, acetyl transferase (NAT1) and sulfotransferase. The increased hepatic clearance of drugs in the presence of CF may be the consequence of disease-specific changes in both enzyme activity and/or drug transport within the liver. The renal clearance (CLR) of many drugs in patients with CF is enhanced although there has been no pathological abnormality identified which could explain this finding: glomerular filtration rate and tubular secretion appear normal in patients with CF. The precise mechanisms for enhanced drug clearance in patients with CF remain to be elucidated. The optimisation of antibiotic therapy in patients with CF includes increasing the dose of beta-lactams by 20 to 30% and monitoring plasma concentrations of aminoglycosides. The appropriate dosage of quinolones has not been definitively established. PMID:9812180

  5. NIH Minority Programs.

    ERIC Educational Resources Information Center

    National Institutes of Health (DHHS), Bethesda, MD.

    This publication contains brief descriptions of National Institutes of Health programs for underrepresented minorities, including fellowships, programs for high school students, graduate research assistantships, postdoctoral training, and programs for college students. The publication provides a description of each program, eligibility…

  6. Minority Women's Health: Latinas

    MedlinePlus

    ... left navigation Minority Women's Health African-Americans Latinas Asian-Americans Native Hawaiians and other Pacific Islanders American Indians/ ... Rican, South or Central American, or other Spanish culture or origin. Latinos may be any race. This ...

  7. Minority workers and communities.

    PubMed

    Frumkin, H; Walker, E D; Friedman-Jiménez, G

    1999-01-01

    Environmental and occupational hazards do not affect all communities equally. Members of ethnic and racial minorities, whether as working people or as community residents, sustain disproportionate risks from chemical, physical, and biological hazards. This paper reviews the nature of these disproportionate risks, focusing primarily on the workplace, but considering general environmental exposures as well. It discusses three principal mechanisms of increased risk: excessive hazardous exposures in both the workplace and the general environment, increased susceptibility, and inferior healthcare. It presents evidence that, as the result of these factors, members of minority groups display elevated rates of work-related illness, injury, fatality, and disability. Finally, it offers recommendations with regard to research, primary prevention, minority recruitment into the occupational health professions, and treatment and compensation for injured and ill minority workers. PMID:10378973

  8. Minority Innovation Challenges Institute

    NASA Video Gallery

    Do you want to learn more about how to compete in NASA’s technical challenges for both prestige and significant cash prizes? NASA’s Minority Innovation Challenges Institute trains and mentors mino...

  9. NRC comprehensive records disposition schedule. Revision 3

    SciTech Connect

    1998-02-01

    Title 44 US Code, ``Public Printing and Documents,`` regulations issued by the General Service Administration (GSA) in 41 CFR Chapter 101, Subchapter B, ``Management and Use of Information and Records,`` and regulations issued by the National Archives and Records Administration (NARA) in 36 CFR Chapter 12, Subchapter B, ``Records Management,`` require each agency to prepare and issue a comprehensive records disposition schedule that contains the NARA approved records disposition schedules for records unique to the agency and contains the NARA`s General Records Schedules for records common to several or all agencies. The approved records disposition schedules specify the appropriate duration of retention and the final disposition for records created or maintained by the NRC. NUREG-0910, Rev. 3, contains ``NRC`s Comprehensive Records Disposition Schedule,`` and the original authorized approved citation numbers issued by NARA. Rev. 3 incorporates NARA approved changes and additions to the NRC schedules that have been implemented since the last revision dated March, 1992, reflects recent organizational changes implemented at the NRC, and includes the latest version of NARA`s General Records Schedule (dated August 1995).

  10. Multichoice minority game

    SciTech Connect

    Ein-Dor, Liat; Metzler, Richard; Kanter, Ido; Kinzel, Wolfgang

    2001-06-01

    The generalization of the problem of adaptive competition, known as the minority game, to the case of K possible choices for each player, is addressed, and applied to a system of interacting perceptrons with input and output units of a type of K-state Potts spins. An optimal solution of this minority game, as well as the dynamic evolution of the adaptive strategies of the players, are solved analytically for a general K and compared with numerical simulations.

  11. Daily Hassles and Coping Dispositions as Predictors of Psychological Adjustment: A Comparative Study of Young Unaccompanied Refugees and Youth in the Resettlement Country

    ERIC Educational Resources Information Center

    Seglem, Karoline B.; Oppedal, Brit; Roysamb, Espen

    2014-01-01

    This study examined daily hassles and coping dispositions in relation to life satisfaction and depressive symptoms among resettled unaccompanied refugees and other youth in the resettlement country. A total of 223 unaccompanied refugees ("M" = 20 years) was compared with 609 ethnic minority and 427 majority youth in Norway. Unaccompanied…

  12. Excess plutonium disposition: The deep borehole option

    SciTech Connect

    Ferguson, K.L.

    1994-08-09

    This report reviews the current status of technologies required for the disposition of plutonium in Very Deep Holes (VDH). It is in response to a recent National Academy of Sciences (NAS) report which addressed the management of excess weapons plutonium and recommended three approaches to the ultimate disposition of excess plutonium: (1) fabrication and use as a fuel in existing or modified reactors in a once-through cycle, (2) vitrification with high-level radioactive waste for repository disposition, (3) burial in deep boreholes. As indicated in the NAS report, substantial effort would be required to address the broad range of issues related to deep bore-hole emplacement. Subjects reviewed in this report include geology and hydrology, design and engineering, safety and licensing, policy decisions that can impact the viability of the concept, and applicable international programs. Key technical areas that would require attention should decisions be made to further develop the borehole emplacement option are identified.

  13. Value-Added Measures of Teacher Candidates' Dispositions

    ERIC Educational Resources Information Center

    Cosgrove, Maryellen; Carpenter, Barbara

    2012-01-01

    This article describes how a teacher preparation program can positively impact professional dispositions. Pre and post essays from a sample of sixty candidates were qualitatively analyzed to determine the value-added growth of their professional dispositions.

  14. 15 CFR 301.7 - Final disposition of an application.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... AND APPARATUS FOR EDUCATIONAL AND SCIENTIFIC INSTITUTIONS § 301.7 Final disposition of an application. (a) Disposition of an application shall be final when 20 days have elapsed after publication of...

  15. POTENTIAL BENCHMARKS FOR ACTINIDE PRODUCTION IN HANFORD REACTORS

    SciTech Connect

    PUIGH RJ; TOFFER H

    2011-10-19

    A significant experimental program was conducted in the early Hanford reactors to understand the reactor production of actinides. These experiments were conducted with sufficient rigor, in some cases, to provide useful information that can be utilized today in development of benchmark experiments that may be used for the validation of present computer codes for the production of these actinides in low enriched uranium fuel.

  16. Process for making a ceramic composition for immobilization of actinides

    DOEpatents

    Ebbinghaus, Bartley B.; Van Konynenburg, Richard A.; Vance, Eric R.; Stewart, Martin W.; Walls, Philip A.; Brummond, William Allen; Armantrout, Guy A.; Herman, Connie Cicero; Hobson, Beverly F.; Herman, David Thomas; Curtis, Paul G.; Farmer, Joseph

    2001-01-01

    Disclosed is a process for making a ceramic composition for the immobilization of actinides, particularly uranium and plutonium. The ceramic is a titanate material comprising pyrochlore, brannerite and rutile. The process comprises oxidizing the actinides, milling the oxides to a powder, blending them with ceramic precursors, cold pressing the blend and sintering the pressed material.

  17. Process for Making a Ceramic Composition for Immobilization of Actinides

    SciTech Connect

    Ebbinghaus, Bartley B.; Van Konynenburg, Richard A.; Vance, Eric R.; Stewart, Martin W.; Walls, Philip A.; Brummond, William Allen; Armantrout, Guy A.; Curtis, Paul G.; Hobson, Beverly F.; Farmer, Joseph; Herman, Connie Cicero; Herman, David Thomas

    1999-06-22

    Disclosed is a process for making a ceramic composition for the immobilization of actinides, particularly uranium and plutonium. The ceramic is a titanate material comprising pyrochlore, brannerite and rutile. The process comprises oxidizing the actinides, milling the oxides to a powder, blending them with ceramic precursors, cold pressing the blend and sintering the pressed material.

  18. Improved method for extracting lanthanides and actinides from acid solutions

    DOEpatents

    Horwitz, E.P.; Kalina, D.G.; Kaplan, L.; Mason, G.W.

    1983-07-26

    A process for the recovery of actinide and lanthanide values from aqueous acidic solutions uses a new series of neutral bi-functional extractants, the alkyl(phenyl)-N,N-dialkylcarbamoylmethylphosphine oxides. The process is suitable for the separation of actinide and lanthanide values from fission product values found together in high-level nuclear reprocessing waste solutions.

  19. Study of actinide chemistry in saturated potassium fluoride solution

    NASA Technical Reports Server (NTRS)

    Cohen, D.; Thalmayer, C. E.

    1969-01-01

    Study concerning the chemistry of actinides in saturated KF solution included work with neptunium, uranium, and americium. Solubilities, absorption spectra, oxidation-reduction reactions, and solid compounds which can be produced in KF solution were examined. The information is used for preparation of various materials from salts of the actinides.

  20. Photofission of Actinides with Linearly Polarized Photons

    SciTech Connect

    Dale, D. S.; Cole, P. L.; Conn, A.; Forest, T. A.; Kosinov, O.; Setiniyaz, S.; Shapovlov, R.; Starovoitova, V.; Swanson, J.; Bodily, R.; Kelley, K.

    2010-08-04

    Idaho State University and the Idaho Accelerator Center are developing a polarized photon facility in the 10 MeV region using the off axis bremsstrahlung technique. Initial tests have been performed with the aim of using the high analyzing power of the photodisintegration of the deuteron to measure the beam polarization. A program is currently underway to measure the potential angular asymmetries of neutrons arising from the angular distribution of the fission fragments from photofission with linearly polarized photons. In this paper, we describe the Idaho State University Polarized Photon Facility, present results of commissioning runs, and describe potential application of polarized photofission in detecting actinides for homeland security and safeguards applications.

  1. Status of nuclear data for actinides

    SciTech Connect

    Guzhovskii, B.Y.; Gorelov, V.P.; Grebennikov, A.N.

    1995-10-01

    Nuclear data required for transmutation problem include many actinide nuclei. In present paper the analysis of neutron fission, capture, (n,2n) and (n,3n) reaction cross sections at energy region from thermal point to 14 MeV was carried out for Th, Pa, U, Np, Pu, Am and Cm isotops using modern evaluated nuclear data libraries and handbooks of recommended nuclear data. Comparison of these data indicates on substantial discrepancies in different versions of files, that connect with quality and completeness of original experimental data.

  2. {alpha} Decay of Deformed Actinide Nuclei

    SciTech Connect

    Stewart, T.L.; Kermode, M.W.; Beachey, D.J.; Rowley, N.; Grant, I.S.; Kruppa, A.T.

    1996-07-01

    {alpha} decay through a deformed potential barrier produces significant mixing of angular momenta when mapped from the nuclear interior to the outside. Using experimental branching ratios and either semiclassical or coupled-channels transmission matrices, we have found that there is a set of internal amplitudes which is essentially constant for all even-even actinide nuclei. These same amplitudes also give good results for the known anisotropic {alpha}-particle emission of the favored decays of odd nuclei in the same mass region. {copyright} {ital 1996 The American Physical Society.}

  3. Surplus Highly Enriched Uranium Disposition Program plan

    SciTech Connect

    1996-10-01

    The purpose of this document is to provide upper level guidance for the program that will downblend surplus highly enriched uranium for use as commercial nuclear reactor fuel or low-level radioactive waste. The intent of this document is to outline the overall mission and program objectives. The document is also intended to provide a general basis for integration of disposition efforts among all applicable sites. This plan provides background information, establishes the scope of disposition activities, provides an approach to the mission and objectives, identifies programmatic assumptions, defines major roles, provides summary level schedules and milestones, and addresses budget requirements.

  4. Separation of actinides from lanthanides utilizing molten salt electrorefining

    SciTech Connect

    Grimmett, D.L.; Fusselman, S.P.; Roy, J.J.; Gay, R.L.; Krueger, C.L.; Storvick, T.S.; Inoue, T.; Hijikata, T.; Takahashi, N.

    1996-10-01

    TRUMP-S (TRansUranic Management through Pyropartitioning Separation) is a pyrochemical process being developed to separate actinides form fission products in nuclear waste. A key process step involving molten salt electrorefining to separate actinides from lanthanides has been studied on a laboratory scale. Electrorefining of U, Np, Pu, Am, and lanthanide mixtures from molten cadmium at 450 C to a solid cathode utilizing a molten chloride electrolyte resulted in > 99% removal of actinides from the molten cadmium and salt phases. Removal of the last few percent of actinides is accompanied by lowered cathodic current efficiency and some lanthanide codeposition. Actinide/lanthanide separation ratios on the cathode are ordered U > Np > Pu > Am and are consistent with predictions based on equilibrium potentials.

  5. Actinides and Rare Earths Topical Conference (Code AC)

    SciTech Connect

    Tobin, J G

    2009-11-24

    Actinide and the Rare Earth materials exhibit many unique and diverse physical, chemical and magnetic properties, in large part because of the complexity of their f electronic structure. This Topical Conference will focus upon the chemistry, physics and materials science in Lanthanide and Actinide materials, driven by 4f and 5f electronic structure. Particular emphasis will be placed upon 4f/5f magnetic structure, surface science and thin film properties. For the actinides, fundamental actinide science and its role in resolving technical challenges posed by actinide materials will be stressed. Both basic and applied experimental approaches, including synchrotron-radiation-based investigations, as well as theoretical modeling and computational simulations, are planned to be part of the Topical Conference. Of particular importance are the issues related to the potential renaissance in Nuclear Fuels, including synthesis, oxidation, corrosion, intermixing, stability in extreme environments, prediction of properties via benchmarked simulations, separation science, environmental impact and disposal of waste products.

  6. Research in actinide chemistry. Progress report, 1990--1993

    SciTech Connect

    Choppin, G.R.

    1993-04-01

    This research studies the behavior of the actinide elements in aqueous solution. The high radioactivity of the transuranium actinides limits the concentrations which can be studied and, consequently, limits the experimental techniques. However, oxidation state analogs (trivalent lanthanides, tetravalent thorium, and hexavalent uranium) do not suffer from these limitations. Behavior of actinides in the environment are a major USDOE concern, whether in connection with long-term releases from a repository, releases from stored defense wastes or accidental releases in reprocessing, etc. Principal goal of our research was expand the thermodynamic data base on complexation of actinides by natural ligands (e.g., OH{sup {minus}}, CO{sub 3}{sup 2{minus}}, PO{sub 4}{sup 3{minus}}, humates). The research undertakes fundamental studies of actinide complexes which can increase understanding of the environmental behavior of these elements.

  7. Actinide-Aluminate Speciation in Alkaline Radioactive Waste

    SciTech Connect

    Dr. David L. Clark; Dr. Alexander M. Fedosseev

    2001-12-21

    Investigation of behavior of actinides in alkaline media containing AL(III) showed that no aluminate complexes of actinides in oxidation states (IIII-VIII) were formed in alkaline solutions. At alkaline precipitation IPH (10-14) of actinides in presence of AL(III) formation of aluminate compounds is not observed. However, in precipitates contained actinides (IIV)<(VI), and to a lesser degree actinides (III), some interference of components takes place that is reflected in change of solid phase properties in comparison with pure components or their mechanical mixture. The interference decreases with rise of precipitation PH and at PH 14 is exhibited very feebly. In the case of NP(VII) the individual compound with AL(III) is obtained, however it is not aluminate of neptunium(VII), but neptunate of aluminium(III) similar to neptunates of other metals obtained earlier.

  8. La problématique de la maîtrise de l'inventaire plutonium et actinides mineurs dans le cycle du combustible nucléaire

    NASA Astrophysics Data System (ADS)

    Mouney, Henri

    2002-10-01

    The mastering of the plutonium and minor actinides inventory in the French Nuclear Cycle is based on a progressive approach from the present status, dealing with the partial reprocessing of spent fuels and the recycling of Pu in the MOX assemblies loaded in the 20 licensed PWRs. This strategy keeps the door open long-term, for example, for the eventual multirecycling of excess Pu in dedicated new assemblies, such as APA or CORAIL in order to stabilise the Pu inventory in the fuel cycle or allow its utilization in new types of fast reactors. Presently, in the framework of 1991 law, scenario studies relying on present and/or innovative technologies are carried out in order to transmute both Pu and minor actinides, thus minimising the quantities to be for disposal. To cite this article: H. Mouney, C. R. Physique 3 (2002) 773-782.

  9. Mission Need Statement: Calcine Disposition Project Major Systems Acquisition Project

    SciTech Connect

    J. T. Beck

    2007-04-26

    This document identifies the need to establish the Calcine Disposition Project to determine and implement the final disposition of calcine including characterization, retrieval, treatment (if necessary), packaging, loading, onsite interim storage pending shipment to a repository or interim storage facility, and disposition of related facilities.

  10. 32 CFR 736.4 - Disposition of real property.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Disposition of real property. 736.4 Section 736.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PROCUREMENT, PROPERTY, PATENTS, AND CONTRACTS DISPOSITION OF PROPERTY § 736.4 Disposition of real property. (a) Real...

  11. 32 CFR 736.4 - Disposition of real property.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 5 2013-07-01 2013-07-01 false Disposition of real property. 736.4 Section 736.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PROCUREMENT, PROPERTY, PATENTS, AND CONTRACTS DISPOSITION OF PROPERTY § 736.4 Disposition of real property. (a) Real...

  12. 32 CFR 736.4 - Disposition of real property.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 5 2011-07-01 2011-07-01 false Disposition of real property. 736.4 Section 736.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PROCUREMENT, PROPERTY, PATENTS, AND CONTRACTS DISPOSITION OF PROPERTY § 736.4 Disposition of real property. (a) Real...

  13. 32 CFR 736.4 - Disposition of real property.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 5 2014-07-01 2014-07-01 false Disposition of real property. 736.4 Section 736.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PROCUREMENT, PROPERTY, PATENTS, AND CONTRACTS DISPOSITION OF PROPERTY § 736.4 Disposition of real property. (a) Real...

  14. 32 CFR 736.4 - Disposition of real property.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Disposition of real property. 736.4 Section 736.4 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PROCUREMENT, PROPERTY, PATENTS, AND CONTRACTS DISPOSITION OF PROPERTY § 736.4 Disposition of real property. (a) Real...

  15. 32 CFR 552.125 - Disposition of confiscated weapons.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 3 2012-07-01 2009-07-01 true Disposition of confiscated weapons. 552.125..., Ammunition, and Explosives-Fort Lewis, Washington § 552.125 Disposition of confiscated weapons. Commanders will maintain confiscated weapons in the unit arms room pending final disposition. They will...

  16. 32 CFR 552.125 - Disposition of confiscated weapons.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 3 2013-07-01 2013-07-01 false Disposition of confiscated weapons. 552.125..., Ammunition, and Explosives-Fort Lewis, Washington § 552.125 Disposition of confiscated weapons. Commanders will maintain confiscated weapons in the unit arms room pending final disposition. They will...

  17. 32 CFR 552.125 - Disposition of confiscated weapons.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 3 2011-07-01 2009-07-01 true Disposition of confiscated weapons. 552.125..., Ammunition, and Explosives-Fort Lewis, Washington § 552.125 Disposition of confiscated weapons. Commanders will maintain confiscated weapons in the unit arms room pending final disposition. They will...

  18. 32 CFR 552.125 - Disposition of confiscated weapons.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Disposition of confiscated weapons. 552.125..., Ammunition, and Explosives-Fort Lewis, Washington § 552.125 Disposition of confiscated weapons. Commanders will maintain confiscated weapons in the unit arms room pending final disposition. They will...

  19. 32 CFR 552.125 - Disposition of confiscated weapons.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 3 2014-07-01 2014-07-01 false Disposition of confiscated weapons. 552.125..., Ammunition, and Explosives-Fort Lewis, Washington § 552.125 Disposition of confiscated weapons. Commanders will maintain confiscated weapons in the unit arms room pending final disposition. They will...

  20. Measuring Teacher Educators' Researcherly Disposition: Item Development and Scale Construction

    ERIC Educational Resources Information Center

    Tack, Hanne; Vanderlinde, Ruben

    2016-01-01

    This study reports on the development of a self-reported measurement instrument--The Teacher Educators' Researcherly Disposition Scale (TERDS)--to improve understanding of teacher educators' researcherly disposition. Teacher educators' researcherly disposition refers to the habit of mind to engage with research--both as consumers and producers--to…

  1. 43 CFR 16.2 - Applications for helium disposition agreements.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Applications for helium disposition... HELIUM § 16.2 Applications for helium disposition agreements. The application for a helium disposition... Secretary to determine that the proposal will conserve helium that will otherwise be wasted, drained,...

  2. 43 CFR 16.2 - Applications for helium disposition agreements.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Applications for helium disposition... HELIUM § 16.2 Applications for helium disposition agreements. The application for a helium disposition... Secretary to determine that the proposal will conserve helium that will otherwise be wasted, drained,...

  3. 43 CFR 16.2 - Applications for helium disposition agreements.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Applications for helium disposition... HELIUM § 16.2 Applications for helium disposition agreements. The application for a helium disposition... Secretary to determine that the proposal will conserve helium that will otherwise be wasted, drained,...

  4. 43 CFR 16.2 - Applications for helium disposition agreements.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Applications for helium disposition... HELIUM § 16.2 Applications for helium disposition agreements. The application for a helium disposition... Secretary to determine that the proposal will conserve helium that will otherwise be wasted, drained,...

  5. 43 CFR 16.2 - Applications for helium disposition agreements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Applications for helium disposition... HELIUM § 16.2 Applications for helium disposition agreements. The application for a helium disposition... Secretary to determine that the proposal will conserve helium that will otherwise be wasted, drained,...

  6. 47 CFR 76.804 - Disposition of home run wiring.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Disposition of home run wiring. 76.804 Section... MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Inside Wiring § 76.804 Disposition of home run wiring. (a) Building-by-building disposition of home run wiring. (1) Where an MVPD owns the home run wiring in an...

  7. 47 CFR 76.804 - Disposition of home run wiring.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Disposition of home run wiring. 76.804 Section... MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Inside Wiring § 76.804 Disposition of home run wiring. (a) Building-by-building disposition of home run wiring. (1) Where an MVPD owns the home run wiring in an...

  8. 47 CFR 76.804 - Disposition of home run wiring.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Disposition of home run wiring. 76.804 Section... MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Inside Wiring § 76.804 Disposition of home run wiring. (a) Building-by-building disposition of home run wiring. (1) Where an MVPD owns the home run wiring in an...

  9. 12 CFR 34.83 - Disposition of real estate.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 1 2013-01-01 2013-01-01 false Disposition of real estate. 34.83 Section 34.83 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY REAL ESTATE LENDING AND APPRAISALS Other Real Estate Owned § 34.83 Disposition of real estate. (a) Disposition. A national bank...

  10. 12 CFR 34.83 - Disposition of real estate.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 1 2012-01-01 2012-01-01 false Disposition of real estate. 34.83 Section 34.83 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY REAL ESTATE LENDING AND APPRAISALS Other Real Estate Owned § 34.83 Disposition of real estate. (a) Disposition. A national bank...

  11. 12 CFR 34.83 - Disposition of real estate.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 1 2014-01-01 2014-01-01 false Disposition of real estate. 34.83 Section 34.83 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY REAL ESTATE LENDING AND APPRAISALS Other Real Estate Owned § 34.83 Disposition of real estate. (a) Disposition. A national bank...

  12. 12 CFR 34.83 - Disposition of real estate.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Disposition of real estate. 34.83 Section 34.83 Banks and Banking COMPTROLLER OF THE CURRENCY, DEPARTMENT OF THE TREASURY REAL ESTATE LENDING AND APPRAISALS Other Real Estate Owned § 34.83 Disposition of real estate. (a) Disposition. A national bank...

  13. The Critical Thinking Disposition of Alternative Certification Students

    ERIC Educational Resources Information Center

    Jones, Timothy B.

    2003-01-01

    This article examines the disposition toward critical thinking of post-baccalaureate initial certification students at a Texas institution of higher education using the California Critical Thinking Disposition Inventory. The inventory characterizes seven subscales of critical thinking disposition and an eighth combined score for overall critical…

  14. Comparing the Ideal Dispositions of Administrative Internship Candidates

    ERIC Educational Resources Information Center

    Brown, Sidney L.

    2015-01-01

    This research will examine the dispositions of Instructional Leader Residents/interns (ILR/I's) at a State Department of Education (SDE) mandated redesigned masters principal preparation program at a Predominantly White Institution (PWI). Once the dispositions' findings were tabulated they were compared with the dispositions findings of…

  15. From Ability to Action: Designing Instruction for Critical Thinking Dispositions.

    ERIC Educational Resources Information Center

    Leader, Lars F.; Middleton, James A.

    This paper explains the importance of disposition as an essential aspect of critical thinking and suggests how instruction can be designed to promote learners' development of the dispositional side of critical thinking. Topics addressed include: (1) the dispositional bottleneck between opportunity and action, i.e., sensitivity to occasion; (2)…

  16. 31 CFR 8.32 - Prompt disposition of pending matters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Prompt disposition of pending matters... Prompt disposition of pending matters. No attorney, certified public accountant, or enrolled practitioner may unreasonably delay the prompt disposition of any matter before the Bureau....

  17. 31 CFR 10.23 - Prompt disposition of pending matters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Prompt disposition of pending matters... Revenue Service § 10.23 Prompt disposition of pending matters. A practitioner may not unreasonably delay the prompt disposition of any matter before the Internal Revenue Service....

  18. Building Awareness of Dispositions: Enhancing Moral Sensibilities in Teaching

    ERIC Educational Resources Information Center

    Schussler, Deborah L.; Knarr, Lea

    2013-01-01

    The purpose of this paper is to explain why and how dispositions can operate as a mechanism for enhancing teacher candidates' moral sensibilities. Dispositions conjoin the knowledge and skills of teaching with the commitments one has to achieve intended purposes. Dispositions build candidates' awareness of their own perceptions (and…

  19. 32 CFR 736.2 - Dispositions under contracts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 5 2011-07-01 2011-07-01 false Dispositions under contracts. 736.2 Section 736..., PATENTS, AND CONTRACTS DISPOSITION OF PROPERTY § 736.2 Dispositions under contracts. (a) Contractor inventory (that is, personal property acquired by a contractor under terms vesting title in the...

  20. 32 CFR 736.2 - Dispositions under contracts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 5 2010-07-01 2010-07-01 false Dispositions under contracts. 736.2 Section 736..., PATENTS, AND CONTRACTS DISPOSITION OF PROPERTY § 736.2 Dispositions under contracts. (a) Contractor inventory (that is, personal property acquired by a contractor under terms vesting title in the...

  1. 12 CFR 1780.32 - Partial summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Partial summary disposition. 1780.32 Section... § 1780.32 Partial summary disposition. If the presiding officer determines that a party is entitled to summary disposition as to certain claims only, he shall defer submitting a recommended decision to...

  2. 12 CFR 308.30 - Partial summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 4 2011-01-01 2011-01-01 false Partial summary disposition. 308.30 Section 308... PRACTICE AND PROCEDURE Uniform Rules of Practice and Procedure § 308.30 Partial summary disposition. If the administrative law judge determines that a party is entitled to summary disposition as to certain claims only,...

  3. 18 CFR 385.217 - Summary disposition (Rule 217).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Summary disposition... Filings, Notices of Tariff or Rate Examination, Orders To Show Cause, Intervention, and Summary Disposition § 385.217 Summary disposition (Rule 217). (a) Applicability. This section applies to: (1)...

  4. 12 CFR 509.30 - Partial summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 5 2011-01-01 2011-01-01 false Partial summary disposition. 509.30 Section 509... PROCEDURE IN ADJUDICATORY PROCEEDINGS Uniform Rules of Practice and Procedure § 509.30 Partial summary disposition. If the administrative law judge determines that a party is entitled to summary disposition as...

  5. 18 CFR 385.217 - Summary disposition (Rule 217).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Summary disposition... Filings, Notices of Tariff or Rate Examination, Orders To Show Cause, Intervention, and Summary Disposition § 385.217 Summary disposition (Rule 217). (a) Applicability. This section applies to: (1)...

  6. 12 CFR 19.30 - Partial summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 1 2010-01-01 2010-01-01 false Partial summary disposition. 19.30 Section 19... PROCEDURE Uniform Rules of Practice and Procedure § 19.30 Partial summary disposition. If the administrative law judge determines that a party is entitled to summary disposition as to certain claims only, he...

  7. 12 CFR 1780.32 - Partial summary disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 7 2011-01-01 2011-01-01 false Partial summary disposition. 1780.32 Section... § 1780.32 Partial summary disposition. If the presiding officer determines that a party is entitled to summary disposition as to certain claims only, he shall defer submitting a recommended decision to...

  8. 12 CFR 263.30 - Partial summary disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Partial summary disposition. 263.30 Section 263... SYSTEM RULES OF PRACTICE FOR HEARINGS Uniform Rules of Practice and Procedure § 263.30 Partial summary disposition. If the administrative law judge determines that a party is entitled to summary disposition as...

  9. 7 CFR 1435.401 - CCC sugar inventory disposition.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false CCC sugar inventory disposition. 1435.401 Section... CORPORATION, DEPARTMENT OF AGRICULTURE LOANS, PURCHASES, AND OTHER OPERATIONS SUGAR PROGRAM Disposition of CCC Inventory § 1435.401 CCC sugar inventory disposition. (a) CCC will dispose of inventory in the...

  10. 50 CFR 30.2 - Disposition of surplus range animals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Disposition of surplus range animals. 30.2... (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range animals. Disposition shall be made only during regularly scheduled...

  11. 50 CFR 30.2 - Disposition of surplus range animals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Disposition of surplus range animals. 30.2... (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range animals. Disposition shall be made only during regularly scheduled...

  12. 50 CFR 30.2 - Disposition of surplus range animals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Disposition of surplus range animals. 30.2... (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range animals. Disposition shall be made only during regularly scheduled...

  13. 50 CFR 30.2 - Disposition of surplus range animals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Disposition of surplus range animals. 30.2... (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range animals. Disposition shall be made only during regularly scheduled...

  14. 50 CFR 30.2 - Disposition of surplus range animals.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Disposition of surplus range animals. 30.2... (CONTINUED) THE NATIONAL WILDLIFE REFUGE SYSTEM RANGE AND FERAL ANIMAL MANAGEMENT Range Animals § 30.2 Disposition of surplus range animals. Disposition shall be made only during regularly scheduled...

  15. Dispositions and Preservice Teachers of the Millennial Generation

    ERIC Educational Resources Information Center

    Austin, Kenneth R.

    2009-01-01

    In this article, I argue that teacher preparation programs must address the dispositions that lead to successful patterns of professional conduct and attitudes. I situate the thesis within the discussion on dispositions and the focus on preparing teachers of the millennial generation. I further examine the dispositions that the millennial students…

  16. 32 CFR 736.2 - Dispositions under contracts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 5 2012-07-01 2012-07-01 false Dispositions under contracts. 736.2 Section 736.2 National Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY PROCUREMENT, PROPERTY, PATENTS, AND CONTRACTS DISPOSITION OF PROPERTY § 736.2 Dispositions under contracts. (a)...

  17. Development of a new casting method to fabricate U–Zr alloy containing minor actinides

    SciTech Connect

    Jong Hwan Kim; Hoon Song; Hyung Tae Kim; Ki Hwan Kim; Chan Bock Lee; R. S. Fielding

    2014-01-01

    Metal fuel slugs of U–Zr alloys for a sodium-cooled fast reactor (SFR) have conventionally been fabricated using an injection casting method. However, casting alloys containing volatile radioactive constituents, such as Am, are problematic in a conventional injection casting method. As an alternative fabrication method, low pressure gravity casting has been developed. Casting soundness, microstructural characteristics, alloying composition, density, and fuel losses were evaluated for the following as-cast fuel slugs: U–10 wt% Zr, U–10 wt% Zr–5 wt% RE, and U–10 wt% Zr–5 wt% RE–5 wt% Mn. The U and Zr contents were uniform throughout the matrix, and impurities such as oxyen, carbon, and nitrogen satisfied the specification of total impurities less than 2,000 ppm. The appearance of the fuel slugs was generally sound, and the internal integrity was shown to be satisfactory based on gamma-ray radiography. In a volatile surrogate casting test, the U–Zr–RE–Mn fuel slug showed that nearly all of the manganese was retained when casting was done under an inert atmosphere.

  18. Core-hole effect on XANES and electronic structure of minor actinide dioxides with fluorite structure

    NASA Astrophysics Data System (ADS)

    Suzuki, Chikashi; Nishi, Tsuyoshi; Nakada, Masami; Akabori, Mitsuo; Hirata, Masaru; Kaji, Yoshiyuki

    2012-02-01

    The authors investigated theoretically core-hole effects on X-ray absorption near-edge structures (XANES) of Np and Am LIII in neptunium dioxide (NpO2) and americium dioxide (AmO2) with CaF2-type crystal lattices using the all-electron full-potential linearized augmented plane-wave (FP-LAPW) method. The peak creation mechanism of XANES was shown by examining the electronic structures of these oxides, which indicated that core-hole screening was more marked for AmO2 than for NpO2 because of the difference in the charge transfer between these oxides. Furthermore, the results of charge density analysis suggested that the white line was assigned to the quasi-bound state composed of the localized Np d or Am d components and O components, and that the tail structure was created as a result of delocalized standing waves between the Np or Am atoms.

  19. Gamma-radiolytic stability of new methylated TODGA derivatives for minor actinide recycling.

    PubMed

    Galán, Hitos; Zarzana, Christopher A; Wilden, Andreas; Núñez, Ana; Schmidt, Holger; Egberink, Richard J M; Leoncini, Andrea; Cobos, Joaquín; Verboom, Willem; Modolo, Giuseppe; Groenewold, Gary S; Mincher, Bruce J

    2015-11-01

    The stability against gamma radiation of MeTODGA (methyl tetraoctyldiglycolamide) and Me2TODGA (dimethyl tetraoctyldiglycolamide), derivatives from the well-known extractant TODGA (N,N,N',N'-tetraoctyldiglycolamide), were studied and compared. Solutions of MeTODGA and Me2TODGA in alkane diluents were subjected to (60)Co γ-irradiation in the presence and absence of nitric acid and analyzed using LC-MS to determine their rates of radiolytic concentration decrease, as well as to identify radiolysis products. The results of product identification from three different laboratories are compared and found to be in good agreement. The diglycolamide (DGA) concentrations decreased exponentially with increasing absorbed dose. The MeTODGA degradation rate constants (dose constants) were uninfluenced by the presence of nitric acid, but the acid increased the rate of degradation for Me2TODGA. The degradation products formed by irradiation are also initially produced in greater amounts in acid-contacted solution, but products may also be degraded by continued radiolysis. The identified radiolysis products suggest that the weakest bonds are those in the diglycolamide center of these molecules. PMID:26412572

  20. Minor actinide separation: simplification of the DIAMEX-SANEX strategy by means of novel SANEX processes

    SciTech Connect

    Geist, A.; Modolo, G.; Wilden, A.; Kaufholz, P.

    2013-07-01

    The separation of An(III) from PUREX raffinate has previously been demonstrated by applying a DIAMEX process (i.e., co-extraction of An(III) and Ln(III) from HAR) followed by a SANEX process (i.e., selective extraction of An(III) from the DIAMEX product containing An(III) + Ln(III)). In line with process intensification issues, more compact processes have been developed: Recently, a 1c-SANEX process test was successfully performed, directly extracting An(III) from PUREX HAR. More recently, a new i-SANEX process was successfully tested. This process is based on the co-extraction of An(III) + Ln(III) into a TODGA solvent, followed by a selective back-extraction of An(III) by a water soluble complexing agent, in this case SO{sub 3}-Ph-BTP. In both cases, good recoveries were achieved, and very pure product solutions were obtained. However, both 1c-SANEX and i-SANEX used non-CHON chemicals. Nevertheless, these processes are a simplification to the DIAMEX + SANEX process as only one solvent is used. Finally, the new i-SANEX process is the most compact process. (authors)

  1. Gamma-radiolytic stability of new methylated TODGA derivatives for minor actinide recycling

    DOE PAGESBeta

    Galan, Hitos; Zarzana, Christopher A.; Wilden, Andreas; Nunez, Ana; Schmidt, Holger; Egberink, Richard J. M.; Leoncini, Andrea; Cobos, Joaquin; Verboom, Willem; Modolo, Giuseppe; et al

    2015-09-15

    The stability against gamma radiation of MeTODGA (methyl tetraoctyldiglycolamide) and Me2TODGA (dimethyl tetraoctyldiglycolamide), derivatives from the well-known extractant TODGA (N,N,N',N';-tetraoctyldiglycolamide), were studied and compared. Solutions of MeTODGA and Me2TODGA in alkane diluents were subjected to 60Co γ-irradiation in the presence and absence of nitric acid and analyzed using LC-MS to determine their rates of radiolytic concentration decrease, as well as to identify radiolysis products. The results of product identification from three different laboratories are compared and found to be in good agreement. The diglycolamide (DGA) concentrations decreased exponentially with increasing absorbed dose. The MeTODGA degradation rate constants (dose constants) weremore » uninfluenced by the presence of nitric acid, but the acid increased the rate of degradation for Me2TODGA. The degradation products formed by irradiation are also initially produced in greater amounts in acid-contacted solution, but products may also be degraded by continued radiolysis. As a result, the identified radiolysis products suggest that the weakest bonds are those in the diglycolamide center of these molecules.« less

  2. Gamma-radiolytic stability of new methylated TODGA derivatives for minor actinide recycling

    SciTech Connect

    Galan, Hitos; Zarzana, Christopher A.; Wilden, Andreas; Nunez, Ana; Schmidt, Holger; Egberink, Richard J. M.; Leoncini, Andrea; Cobos, Joaquin; Verboom, Willem; Modolo, Giuseppe; Groenewold, Gary S.; Mincher, Bruce J.

    2015-09-15

    The stability against gamma radiation of MeTODGA (methyl tetraoctyldiglycolamide) and Me2TODGA (dimethyl tetraoctyldiglycolamide), derivatives from the well-known extractant TODGA (N,N,N',N';-tetraoctyldiglycolamide), were studied and compared. Solutions of MeTODGA and Me2TODGA in alkane diluents were subjected to 60Co γ-irradiation in the presence and absence of nitric acid and analyzed using LC-MS to determine their rates of radiolytic concentration decrease, as well as to identify radiolysis products. The results of product identification from three different laboratories are compared and found to be in good agreement. The diglycolamide (DGA) concentrations decreased exponentially with increasing absorbed dose. The MeTODGA degradation rate constants (dose constants) were uninfluenced by the presence of nitric acid, but the acid increased the rate of degradation for Me2TODGA. The degradation products formed by irradiation are also initially produced in greater amounts in acid-contacted solution, but products may also be degraded by continued radiolysis. As a result, the identified radiolysis products suggest that the weakest bonds are those in the diglycolamide center of these molecules.

  3. NMR Spectroscopy and Structural Characterization of Dithiophosphinates Relevant to Minor Actinide Extraction Processes

    SciTech Connect

    Scott R. Daly; Kevin S. Boland; John R. Klaehn; Stosh A. Kozimor; Molly M. MacInnes; Dean R. Peterman; Brian L. Scott

    2012-02-01

    Synthetic routes to alkyl and aryl substituted dithiophosphinate salts that contain non-coordinating PPh{sub 4}{sup 1+} counter cations are reported. In general, these compounds can be prepared via a multi-step procedure that starts with reacting secondary phosphines, i.e. HPR{sub 2}, with two equivalents elemental S. This transformation proceeds in two steps - first oxidation of the phosphine and second insertion of S into the H-P bond - and has been used to synthesize a series of dithiophoshinic acids, which were fully characterized, namely HS{sub 2}P(p-CF{sub 3}C{sub 6}H{sub 4}){sub 2}, HS{sub 2}P(m-CF{sub 3}C{sub 6}H{sub 4}){sub 2}, HS{sub 2}P(o-MeC{sub 6}H{sub 4}){sub 2}, and HS{sub 2}P(o-MeOC{sub 6}H{sub 4}){sub 2}. Although the insertion step was found to be much slower than the oxidation reaction, the formation of (NH{sub 4})S{sub 2}PR{sub 2} from HPSR{sub 2} occurs almost instantaneous upon addition of NH{sub 4}OH. Subsequent cation exchange reactions proceed readily with PPh{sub 4}Cl in water, under air, and at ambient conditions to provide analytically pure samples of [PPh{sub 4}][S{sub 2}PR{sub 2}] (R = p-CF{sub 3}C{sub 6}H{sub 4}, m-CF{sub 3}C{sub 6}H{sub 4}, o-CF{sub 3}C{sub 6}H{sub 4}, o-MeC{sub 6}H{sub 4}, o-MeOC{sub 6}H{sub 4}, Ph, and Me, 1b-7b, respectively), which were characterized by elemental analysis, multinuclear NMR, and IR spectroscopy. In addition the S{sub 2}PMe{sub 2}{sup 1-}, S{sub 2}PPh{sub 2}{sup 1-}, and dithiophosphinates with ortho-substituted arene rings were characterized by X-ray crystallography. Structural analysis show that, as opposed to the acids which have short P=S double bonds and long P-SH single bonds, the metric parameters for the S atoms in S{sub 2}PR{sub 2}{sup 1-} are equivalent. In addition, the presence of large non-coordinating PPh{sub 4}{sup 1+} cations guard against intermolecular P-S {hor_ellipsis} X interactions and insure that the P-S bond is isolated. Overall, this synthetic procedure provides high-purity S{sub 2}PR{sub 2}{sup 1-} compounds necessary for subsequent spectroscopic and theoretical studies.

  4. An Approach for Validating Actinide and Fission Product Burnup Credit Criticality Safety Analyses: Criticality (keff) Predictions

    SciTech Connect

    Scaglione, John M.; Mueller, Don E.; Wagner, John C.

    2014-12-01

    One of the most important remaining challenges associated with expanded implementation of burnup credit in the United States is the validation of depletion and criticality calculations used in the safety evaluation—in particular, the availability and use of applicable measured data to support validation, especially for fission products (FPs). Applicants and regulatory reviewers have been constrained by both a scarcity of data and a lack of clear technical basis or approach for use of the data. In this study, this paper describes a validation approach for commercial spent nuclear fuel (SNF) criticality safety (keff) evaluations based on best-available data and methods and applies the approach for representative SNF storage and transport configurations/conditions to demonstrate its usage and applicability, as well as to provide reference bias results. The criticality validation approach utilizes not only available laboratory critical experiment (LCE) data from the International Handbook of Evaluated Criticality Safety Benchmark Experiments and the French Haut Taux de Combustion program to support validation of the principal actinides but also calculated sensitivities, nuclear data uncertainties, and limited available FP LCE data to predict and verify individual biases for relevant minor actinides and FPs. The results demonstrate that (a) sufficient critical experiment data exist to adequately validate keff calculations via conventional validation approaches for the primary actinides, (b) sensitivity-based critical experiment selection is more appropriate for generating accurate application model bias and uncertainty, and (c) calculated sensitivities and nuclear data uncertainties can be used for generating conservative estimates of bias for minor actinides and FPs. Results based on the SCALE 6.1 and the ENDF/B-VII.0 cross-section libraries indicate that a conservative estimate of the bias for the minor actinides and FPs is 1.5% of their worth

  5. Actinide Solubility and Speciation in the WIPP

    SciTech Connect

    Reed, Donald T.

    2015-11-02

    The presentation begins with the role and need for nuclear repositories (overall concept, international updates (Sweden, Finland, France, China), US approach and current status), then moves on to the WIPP TRU repository concept (design, current status--safety incidents of February 5 and 14, 2014, path forward), and finally considers the WIPP safety case: dissolved actinide concentrations (overall approach, oxidation state distribution and redox control, solubility of actinides, colloidal contribution and microbial effects). The following conclusions are set forth: (1) International programs are moving forward, but at a very slow and somewhat sporadic pace. (2) In the United States, the Salt repository concept, from the perspective of the long-term safety case, remains a viable option for nuclear waste management despite the current operational issues/concerns. (3) Current model/PA prediction (WIPP example) are built on redundant conservatisms. These conservatisms are being addressed in the ongoing and future research to fill existing data gaps--redox control of plutonium by Fe(0, II), thorium (analog) solubility studies in simulated brine, contribution of intrinsic and biocolloids to the mobile concentration, and clarification of microbial ecology and effects.

  6. Fusion-Fission Burner for Transuranic Actinides

    NASA Astrophysics Data System (ADS)

    Choi, Chan

    2013-10-01

    The 14-MeV DT fusion neutron spectrum from mirror confinement fusion can provide a unique capability to transmute the transuranic isotopes from light water reactors (LWR). The transuranic (TRU) actinides, high-level radioactive wastes, from spent LWR fuel pose serious worldwide problem with long-term decay heat and radiotoxicity. However, ``transmuted'' TRU actinides can not only reduce the inventory of the TRU in the spent fuel repository but also generate additional energy. Typical commercial LWR fuel assemblies for BWR (boiling water reactor) and PWR (pressurized water reactor) measure its assembly lengths with 4.470 m and 4.059 m, respectively, while its corresponding fuel rod lengths are 4.064 m and 3.851 m. Mirror-based fusion reactor has inherently simple geometry for transmutation blanket with steady-state reactor operation. Recent development of gas-dynamic mirror configuration has additional attractive feature with reduced size in central plasma chamber, thus providing a unique capability for incorporating the spent fuel assemblies into transmutation blanket designs. The system parameters for the gas-dynamic mirror-based hybrid burner will be discussed.

  7. Evaluation of actinide biosorption by microorganisms

    SciTech Connect

    Happel, A.M.

    1996-06-01

    Conventional methods for removing metals from aqueous solutions include chemical precipitation, chemical oxidation or reduction, ion exchange, reverse osmosis, electrochemical treatment and evaporation. The removal of radionuclides from aqueous waste streams has largely relied on ion exchange methods which can be prohibitively costly given increasingly stringent regulatory effluent limits. The use of microbial cells as biosorbants for heavy metals offers a potential alternative to existing methods for decontamination or recovery of heavy metals from a variety of industrial waste streams and contaminated ground waters. The toxicity and the extreme and variable conditions present in many radionuclide containing waste streams may preclude the use of living microorganisms and favor the use of non-living biomass for the removal of actinides from these waste streams. In the work presented here, we have examined the biosorption of uranium by non-living, non-metabolizing microbial biomass thus avoiding the problems associated with living systems. We are investigating biosorption with the long term goal of developing microbial technologies for the remediation of actinides.

  8. Characterizing surplus US plutonium for disposition

    SciTech Connect

    Allender, Jeffrey S.; Moore, Edwin N.

    2013-02-26

    The United States (US) has identified 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. The Savannah River National Laboratory (SRNL) operates a Feed Characterization program for the Office of Fissile Materials Disposition (OFMD) of the National Nuclear Security Administration (NNSA) and the DOE Office of Environmental Management (DOE-EM). SRNL manages a broad program of item tracking through process history, laboratory analysis, and non-destructive assay. A combination of analytical techniques allows SRNL to predict the isotopic and chemical properties that qualify materials for disposition through the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). The research also defines properties that are important for other disposition paths, including disposal to the Waste Isolation Pilot Plant (WIPP) as transuranic waste (TRUW) or to high-level waste (HLW) systems.

  9. 36 CFR 215.17 - Informal disposition.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... distances, alternative types of meetings (such as telephone conferences or video conferences) may be... and reconsideration of decisions to take action guidance in FSH 1909.15, Chapter 10, section 18, and... and disposition of the unresolved portion of the appeal shall continue (§ 215.18)....

  10. 45 CFR 689.9 - Dispositions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... official pursuant to 2 CFR part 180 and the procedures of 2 CFR part 180 will be followed, but: (i) The... 45 Public Welfare 3 2013-10-01 2013-10-01 false Dispositions. 689.9 Section 689.9 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION RESEARCH MISCONDUCT §...

  11. 45 CFR 689.9 - Dispositions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... official pursuant to 2 CFR part 180 and the procedures of 2 CFR part 180 will be followed, but: (i) The... 45 Public Welfare 3 2012-10-01 2012-10-01 false Dispositions. 689.9 Section 689.9 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION RESEARCH MISCONDUCT §...

  12. 45 CFR 689.9 - Dispositions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... official pursuant to 2 CFR part 180 and the procedures of 2 CFR part 180 will be followed, but: (i) The... 45 Public Welfare 3 2014-10-01 2014-10-01 false Dispositions. 689.9 Section 689.9 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION RESEARCH MISCONDUCT §...

  13. Characterizing Surplus US Plutonium for Disposition - 13199

    SciTech Connect

    Allender, Jeffrey S.; Moore, Edwin N.

    2013-07-01

    The United States (US) has identified 61.5 metric tons (MT) of plutonium that is permanently excess to use in nuclear weapons programs, including 47.2 MT of weapons-grade plutonium. Surplus inventories will be stored safely by the Department of Energy (DOE) and then transferred to facilities that will prepare the plutonium for permanent disposition. The Savannah River National Laboratory (SRNL) operates a Feed Characterization program for the Office of Fissile Materials Disposition (OFMD) of the National Nuclear Security Administration (NNSA) and the DOE Office of Environmental Management (DOE-EM). SRNL manages a broad program of item tracking through process history, laboratory analysis, and non-destructive assay. A combination of analytical techniques allows SRNL to predict the isotopic and chemical properties that qualify materials for disposition through the Mixed Oxide (MOX) Fuel Fabrication Facility (MFFF). The research also defines properties that are important for other disposition paths, including disposal to the Waste Isolation Pilot Plant (WIPP) as transuranic waste (TRUW) or to high-level waste (HLW) systems. (authors)

  14. 19 CFR 12.20 - Disposition.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... SPECIAL CLASSES OF MERCHANDISE Viruses, Serums, and Toxins for Treatment of Domestic Animals § 12.20 Disposition. Viruses, serums, or toxins rejected by the Department of Agriculture shall be released by the... of the importer if exportation is authorized by the Department of Agriculture. Viruses,...

  15. 19 CFR 12.20 - Disposition.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SPECIAL CLASSES OF MERCHANDISE Viruses, Serums, and Toxins for Treatment of Domestic Animals § 12.20 Disposition. Viruses, serums, or toxins rejected by the Department of Agriculture shall be released by the... of the importer if exportation is authorized by the Department of Agriculture. Viruses,...

  16. 19 CFR 12.20 - Disposition.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SPECIAL CLASSES OF MERCHANDISE Viruses, Serums, and Toxins for Treatment of Domestic Animals § 12.20 Disposition. Viruses, serums, or toxins rejected by the Department of Agriculture shall be released by the... of the importer if exportation is authorized by the Department of Agriculture. Viruses,...

  17. 7 CFR 1000.3 - Route disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Route disposition. 1000.3 Section 1000.3 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE GENERAL PROVISIONS OF FEDERAL MILK MARKETING...

  18. 19 CFR 12.44 - Disposition.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Disposition. 12.44 Section 12.44 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Merchandise Produced by Convict, Forced, Or Indentured Labor §...

  19. 19 CFR 12.44 - Disposition.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Disposition. 12.44 Section 12.44 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Merchandise Produced by Convict, Forced, Or Indentured Labor §...

  20. 19 CFR 12.44 - Disposition.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Disposition. 12.44 Section 12.44 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Merchandise Produced by Convict, Forced, Or Indentured Labor §...

  1. 19 CFR 12.44 - Disposition.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Disposition. 12.44 Section 12.44 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Merchandise Produced by Convict, Forced, Or Indentured Labor §...

  2. 19 CFR 12.44 - Disposition.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Disposition. 12.44 Section 12.44 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Merchandise Produced by Convict, Forced, Or Indentured Labor §...

  3. Teacher Dispositions: Envisioning Their Role in Education

    ERIC Educational Resources Information Center

    Koeppen, Kim E.; Davison-Jenkins, Judith

    2007-01-01

    In this book, Kim E. Koeppen and Judith Davison-Jenkins document their journey in developing and implementing assessment tools designed to reinforce and encourage teacher dispositions that support effective teaching and learning. This book--which contains insights from a variety of teacher candidates and inservice teachers--will spark dialogue…

  4. 27 CFR 44.199 - Disposition.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... OF THE TREASURY (CONTINUED) TOBACCO EXPORTATION OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES, WITHOUT PAYMENT OF TAX, OR WITH DRAWBACK OF TAX Removal of Shipments of Tobacco Products and Cigarette... Disposition. After actual removal from his factory or export warehouse of the shipment described on the...

  5. 27 CFR 44.199 - Disposition.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2011-04-01 2011-04-01 false Disposition. 44.199 Section 44.199 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY (CONTINUED) TOBACCO EXPORTATION OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES, WITHOUT PAYMENT OF TAX, OR WITH DRAWBACK OF...

  6. 27 CFR 44.199 - Disposition.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... THE TREASURY (CONTINUED) TOBACCO EXPORTATION OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES, WITHOUT PAYMENT OF TAX, OR WITH DRAWBACK OF TAX Removal of Shipments of Tobacco Products and Cigarette... Disposition. After actual removal from his factory or export warehouse of the shipment described on the...

  7. 27 CFR 44.199 - Disposition.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... OF THE TREASURY (CONTINUED) TOBACCO EXPORTATION OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES, WITHOUT PAYMENT OF TAX, OR WITH DRAWBACK OF TAX Removal of Shipments of Tobacco Products and Cigarette... Disposition. After actual removal from his factory or export warehouse of the shipment described on the...

  8. 27 CFR 44.199 - Disposition.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... OF THE TREASURY (CONTINUED) TOBACCO EXPORTATION OF TOBACCO PRODUCTS AND CIGARETTE PAPERS AND TUBES, WITHOUT PAYMENT OF TAX, OR WITH DRAWBACK OF TAX Removal of Shipments of Tobacco Products and Cigarette... Disposition. After actual removal from his factory or export warehouse of the shipment described on the...

  9. 48 CFR 1450.103-6 - Disposition.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Disposition. 1450.103-6 Section 1450.103-6 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT... information in support of the request required by FAR 50.103-4, the results of the CO's investigation...

  10. 48 CFR 1450.103-6 - Disposition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 5 2010-10-01 2010-10-01 false Disposition. 1450.103-6 Section 1450.103-6 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT... information in support of the request required by FAR 50.103-4, the results of the CO's investigation...

  11. 48 CFR 1450.103-6 - Disposition.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 5 2014-10-01 2014-10-01 false Disposition. 1450.103-6 Section 1450.103-6 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT... information in support of the request required by FAR 50.103-4, the results of the CO's investigation...

  12. 48 CFR 1450.103-6 - Disposition.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Disposition. 1450.103-6 Section 1450.103-6 Federal Acquisition Regulations System DEPARTMENT OF THE INTERIOR CONTRACT MANAGEMENT... information in support of the request required by FAR 50.103-4, the results of the CO's investigation...

  13. Disposition of surplus fissile materials via immobilization

    SciTech Connect

    Gray, L.W.; Kan, T.; Sutcliffe, W.G.; McKibben, J.M.; Danker, W.

    1995-07-23

    In the Cold War aftermath, the US and Russia have agreed to large reductions in nuclear weapons. To aid in the selection of long-term management options, the USDOE has undertaken a multifaceted study to select options for storage and disposition of surplus plutonium (Pu). One disposition alternative being considered is immobilization. Immobilization is a process in which surplus Pu would be embedded in a suitable material to produce an appropriate form for ultimate disposal. To arrive at an appropriate form, we first reviewed published information on HLW immobilization technologies to identify forms to be prescreened. Surviving forms were screened using multi-attribute utility analysis to determine promising technologies for Pu immobilization. We further evaluated the most promising immobilization families to identify and seek solutions for chemical, chemical engineering, environmental, safety, and health problems; these problems remain to be solved before we can make technical decisions about the viability of using the forms for long-term disposition of Pu. All data, analyses, and reports are being provided to the DOE Office of Fissile Materials Disposition to support the Record of Decision that is anticipated in Summer of 1996.

  14. Using Walkthrough Observations to Document Dispositional Actions

    ERIC Educational Resources Information Center

    Danley, Angela; Theiss, Deb

    2015-01-01

    Faculty from a Midwestern university implemented walkthrough observations in a Professional Development Schools (PDS) field experience with elementary and early childhood majors. The instructors researchers used walkthrough observation forms to track, evaluate, and monitor teacher candidate dispositions. The data were collected electronically and…

  15. 32 CFR 154.69 - Records disposition.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... manner as for classified information in accordance with 32 CFR part 159. (b) DoD record repositories... 32 National Defense 1 2010-07-01 2010-07-01 false Records disposition. 154.69 Section 154.69... PERSONNEL SECURITY PROGRAM REGULATION Safeguarding Personnel Security Investigative Records § 154.69...

  16. Understanding Dispositions toward Reading on the Internet

    ERIC Educational Resources Information Center

    Coiro, Julie

    2012-01-01

    Students' perceptions about the Internet's usefulness and potential to engage them in academic learning tasks have been found to influence their success in reading for information in online tasks. This article helps to understand the types of dispositions that adolescents may have toward reading on the Internet and how to characterize these…

  17. Critical Dispositions: Evidence and Expertise in Education

    ERIC Educational Resources Information Center

    Dimitriadis, Greg

    2011-01-01

    Set against the current proliferation of global "difference" and economic realignment, "Critical Dispositions" explores the notions of "evidence" and "expertise" in times of material scarcity. Both have come to the forefront of national and international debate in education as "evidence" and "evidence-based" research and pedagogical practices…

  18. 49 CFR 244.19 - Disposition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TRANSPORTATION REGULATIONS ON SAFETY INTEGRATION PLANS GOVERNING RAILROAD CONSOLIDATIONS, MERGERS, AND ACQUISITIONS OF CONTROL Safety Integration Plans § 244.19 Disposition. (a) Standard of review. FRA reviews an applicant's Safety Integration Plan, and any amendments thereto, to determine whether it provides...

  19. 49 CFR 244.19 - Disposition.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TRANSPORTATION REGULATIONS ON SAFETY INTEGRATION PLANS GOVERNING RAILROAD CONSOLIDATIONS, MERGERS, AND ACQUISITIONS OF CONTROL Safety Integration Plans § 244.19 Disposition. (a) Standard of review. FRA reviews an applicant's Safety Integration Plan, and any amendments thereto, to determine whether it provides...

  20. 49 CFR 244.19 - Disposition.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... TRANSPORTATION REGULATIONS ON SAFETY INTEGRATION PLANS GOVERNING RAILROAD CONSOLIDATIONS, MERGERS, AND ACQUISITIONS OF CONTROL Safety Integration Plans § 244.19 Disposition. (a) Standard of review. FRA reviews an applicant's Safety Integration Plan, and any amendments thereto, to determine whether it provides...

  1. 49 CFR 244.19 - Disposition.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... TRANSPORTATION REGULATIONS ON SAFETY INTEGRATION PLANS GOVERNING RAILROAD CONSOLIDATIONS, MERGERS, AND ACQUISITIONS OF CONTROL Safety Integration Plans § 244.19 Disposition. (a) Standard of review. FRA reviews an applicant's Safety Integration Plan, and any amendments thereto, to determine whether it provides...

  2. 49 CFR 244.19 - Disposition.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... TRANSPORTATION REGULATIONS ON SAFETY INTEGRATION PLANS GOVERNING RAILROAD CONSOLIDATIONS, MERGERS, AND ACQUISITIONS OF CONTROL Safety Integration Plans § 244.19 Disposition. (a) Standard of review. FRA reviews an applicant's Safety Integration Plan, and any amendments thereto, to determine whether it provides...

  3. Professional Judgment and Dispositions in Teacher Education

    ERIC Educational Resources Information Center

    Dottin, Erskine S.

    2009-01-01

    The word "dispositions" has suddenly emerged in the lexicon of teacher educators in the United States of America, and around the globe as found in publications such as "The International Journal of Diversity in Organizations, Communities and Nations and the Journal of the International Society for Teacher Education". However, it is clear from the…

  4. The Mathematical Disposition of Structural Engineers

    ERIC Educational Resources Information Center

    Gainsburg, Julie

    2007-01-01

    This ethnographic study investigated the mathematical disposition of engineers. Structural engineers in two firms were observed in everyday practice. Observation and interview data were analyzed to elucidate the role of mathematics in solving engineering problems and the engineers' perceptions of the status of mathematics relative to other…

  5. 12 CFR 1080.11 - Disposition.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Banking BUREAU OF CONSUMER FINANCIAL PROTECTION RULES RELATING TO INVESTIGATIONS § 1080.11 Disposition. (a... adjudicatory process. Where appropriate, the Bureau also may refer investigations to appropriate federal, state... Assistant Director of the Division of Enforcement is authorized to close Bureau investigations....

  6. 12 CFR 1080.11 - Disposition.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Banking BUREAU OF CONSUMER FINANCIAL PROTECTION RULES RELATING TO INVESTIGATIONS § 1080.11 Disposition. (a... proceedings may be instituted in Federal or State court or pursuant to the Bureau's administrative adjudicatory process. Where appropriate, the Bureau also may refer investigations to appropriate Federal,...

  7. 12 CFR 1080.11 - Disposition.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Banking BUREAU OF CONSUMER FINANCIAL PROTECTION RULES RELATING TO INVESTIGATIONS § 1080.11 Disposition. (a... proceedings may be instituted in Federal or State court or pursuant to the Bureau's administrative adjudicatory process. Where appropriate, the Bureau also may refer investigations to appropriate Federal,...

  8. 7 CFR 1005.3 - Route disposition.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 9 2011-01-01 2011-01-01 false Route disposition. 1005.3 Section 1005.3 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order...

  9. 7 CFR 1005.3 - Route disposition.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 9 2014-01-01 2013-01-01 true Route disposition. 1005.3 Section 1005.3 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order...

  10. 7 CFR 1005.3 - Route disposition.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 9 2012-01-01 2012-01-01 false Route disposition. 1005.3 Section 1005.3 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order...

  11. 7 CFR 1005.3 - Route disposition.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 9 2013-01-01 2013-01-01 false Route disposition. 1005.3 Section 1005.3 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (MARKETING AGREEMENTS AND ORDERS; MILK), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order...

  12. 7 CFR 1005.3 - Route disposition.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 9 2010-01-01 2009-01-01 true Route disposition. 1005.3 Section 1005.3 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE MILK IN THE APPALACHIAN MARKETING AREA Order...

  13. The Roots of Minority Giving.

    ERIC Educational Resources Information Center

    Abbe, M. Ann

    2000-01-01

    Discussion of ways to increase minority giving to colleges and universities debunks the myth of "minorities don't give," and reports a recent study of minority philanthropy, which details philanthropic characteristics of four minority cultures: blacks, Hispanics, Asian Americans, and American Indians. Specific strategies recommended include…

  14. Nurturing the Innovative Minority

    ERIC Educational Resources Information Center

    Gallagher, James J.

    2005-01-01

    This article discusses the innovative minority. Gifted students differ from the average students. There are those who argue that the differences are a matter merely of quantitative degree reference studies of IQ scores, or SAT scores, which are clearly quantitative scales, and point out that gifted students appear at the top level of these scales…

  15. Alcoholism and Minority Populations.

    ERIC Educational Resources Information Center

    Watts, Thomas D.; Wright, Roosevelt, Jr.

    1991-01-01

    Briefly discusses some aspects of the role of the state and the position of minorities in respect to alcoholism policies and services. Includes case study of a Black alcoholic. Refers readers to studies on Black alcoholism, Native American alcoholism, Hispanic alcoholism, and Asian-American alcoholism. (Author/NB)

  16. Minority Student Retention.

    ERIC Educational Resources Information Center

    Henderson, James C.

    1991-01-01

    Discusses the community college's role in Native American education. Describes recruitment, counseling, assessment, remedial, and outreach programs developed by San Juan College to help minority students succeed, and specifically help Native Americans bridge the worlds of public school, reservation, and university. Identifies keys to the programs'…

  17. Positions of minor planets

    NASA Astrophysics Data System (ADS)

    Gressmann, M.

    A continuation of Gressman's (1980) observations is given using the Schmidt-camera 34/40 cm, f = 76. Topocentric positions of several minor planets are presented, and reference stars are obtained from the AGK(3), and applied to the two-star method to avoid any major errors. Parallax constants are also given, along with coordinates for the epoch 1950.0.

  18. Spotlight on Minority Students

    ERIC Educational Resources Information Center

    Yous, Phakdey Chea; Mahamed, Hodman; Kost, Kimberly

    2009-01-01

    This article spotlights minority students in school psychology training programs. Three students from underrepresented backgrounds were asked to reflect on what aspects of their program made them feel welcome and supported. In their discussions, they took the task a step further and furnished ideas about ways in which school psychology training…

  19. Psychological Tests and Minorities.

    ERIC Educational Resources Information Center

    Wright, Brenda Johnson; Isenstein, Vivian R.

    The problems with traditional testing, particularly as they relate to minorities, are discussed; and psychological tests designed specifically for Blacks are reviewed. Considered are general problems, problems with testing at the higher education level and for employment, and moral and legal implications of the testing controversy. The rationale…

  20. Language, Literacy, and Minorities.

    ERIC Educational Resources Information Center

    Skutnabb-Kangas, Tove

    The ideal of a world where bilingualism or multilingualism is a normal and accepted feature is promoted in a commissioned report for International Literacy Year. It is noted that many minority groups are forced into bilingualism as a necessity for survival, but that those skills are rarely seen as an advantage and often seen as a cause of…