Sökning: "actinides"

Visar resultat 11 - 15 av 61 avhandlingar innehållade ordet actinides.

  1. 11. Studies of Accelerator-Driven Systems for Transmutation of Nuclear Waste

    Författare :Marcus Dahlfors; Ane Håkansson; Alfred Hogenbirk; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nuclear physics; transmutation; accelerator-driven systems; Energy Amplifier; subcritical reactors; nuclear waste; Monte Carlo simulation; burnup; actinides; fission products; benchmark; nuclear data; neutron cross sections; sensitivity analysis; neutron source; spallation target; n_TOF experiment; neutron time-of-flight; cross section measurement; FLUKA; EA-MC; MCNP; MCNP-X; EADF; TRADE; Kärnfysik; Nuclear physics; Kärnfysik;

    Sammanfattning : Accelerator-driven systems for transmutation of nuclear waste have been suggested as a means for dealing with spent fuel components that pose potential radiological hazard for long periods of time. While not entirely removing the need for underground waste repositories, this nuclear waste incineration technology provides a viable method for reducing both waste volumes and storage times. LÄS MER

  3. 12. Modélisation théorique de la spectroscopie d'actinides des solvatés

    Författare :Cecile Danilo; Ulf Wahlgren; Valerie Vallet; Jean-Pierre Flament; Timo Fleig; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Actinides; spectra; solution; Chemical physics; Kemisk fysik; kemisk fysik; Chemical Physics;

    Sammanfattning : The framework of this PhD is the interpretation of Nuclear Magnetic Relaxation Dispersion experiments performed on solvated U4+, NpO2+ and PuO22+, which all have an f2 configuration. Unexpectedly the two actinyl ions have a much higher relaxivity than U4+. LÄS MER

  4. 13. Radiolytic Degradation of BTBP type Molecules for Treatment of Used Nuclear Fuel by Solvent Extraction

    Författare :Anna Fermvik; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; transmutation; lanthanides; degradation; solvent extraction; actinides; radiolysis; BTBP; partitioning;

    Sammanfattning : Nuclear fuel that has been discharged from nuclear reactors is highly radiotoxic and must be kept isolated from the biosphere for very long time periods. This requires an advanced final repository. One way to decrease the long-term radiotoxicity and thermal load of the used fuel is Partitioning and Transmutation (P&T). LÄS MER

  5. 14. The effect of radiolysis of BTBP type molecules on distribution ratios

    Författare :Anna Fermvik; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; radiolysis; transmutation; partitioning; BTBP; solvent extraction; lanthanides; actinides;

    Sammanfattning : Partitioning and transmutation of spent nuclear fuel enables a decrease in the long term radiotoxicity and volume of the waste to be disposed. By transforming the long-lived nuclides into shorter-lived or even stable ones, the time required for a final repository to be regarded safe for the environment can decrease from 100,000 years to less than 1,000 years. LÄS MER

  7. 15. Traitement de l'interaction spin-orbite en chimie quantique et application à la réactivité des complexes d'actinides

    Författare :Emmanuel Fromager; Ulf Wahlgren; Christian Teichteil; Michael Dolg; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quantum chemistry; actinides; charge transfer reactions; spin-orbit effects; Physics; Fysik;

    Sammanfattning : The recent methodological developments and the advent of faster computers enable nowadays to investigate theoretically the chemical reactivity of heavy element complexes. As an example we can mention actinide chemistry which is involved in the separation of nuclear wastes. LÄS MER