Sökning: "Actinide"

Visar resultat 1 - 5 av 43 avhandlingar innehållade ordet Actinide.

  1. 1. Theoretical Actinide Chemistry – Methods and Models

    Författare :Pernilla Wåhlin; Ulf Wahlgren; Luis Seijo; Stockholms universitet; []
    Nyckelord :Actinide; Quantum chemistry; Wave function; Density functional theory; Solvent models; Water exchange; Molecular configurations; Multi-reference density functional method; teoretisk fysik; Theoretical Physics;

    Sammanfattning : The chemistry of actinides in aqueous solution is important, and it is essential to build adequate conceptual models and develop methods applicable for actinide systems. The complex electronic structure makes benchmarking necessary. LÄS MER

  3. 2. Studies of extraction and separation of Am(III) and Eu(III) using synergistic extraction with nitrogen coordinating ligands and 2-bromodecanoic acid

    Författare :Åsa Enarsson; Chalmers tekniska högskola; []
    Nyckelord :transmutation; oligopyridines; Am; lathanide; solvent extraction; basicity; actinide; separation; synergism; triazines; Eu;

    Sammanfattning : .... LÄS MER

  4. 3. Solvent Extraction Studies with Substituted Malonamides and Oligopyridines Influence of Structure and Chemical Properties on the Extraction Ability of Trivalent Actinides and Lanthanides

    Författare :Lena Spjuth; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; lanthanide; malonamides; synergism; transmutation; oligopyridines; separation; solvent extraction; actinide; basicity;

    Sammanfattning : Separation and transmutation of spent nuclear fuel has been considered as a complement to direct disposal in a deep geological repository. The time needed for the waste to decay to natural background levels can be drastically decreased if the long-lived radionuclides, mainly the actinides, in the spent nuclear fuel are separated and transmuted to short-lived or stable nuclides. LÄS MER

  5. 4. Why Faster is Better : On Minor Actinide Transmutation in Hard Neutron

    Författare :Daniel Westlén; Jan Wallenius; Marc Delpech; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nuclear physics; nuclear engineering; Atomic physics; Atomfysik;

    Sammanfattning : In this thesis, options for efficient transmutation of transuranium elements are discussed. The focus is on plutonium, americium and curium mainly because of their long-term contribution to the radiotoxicity of spent nuclear fuel. Two innovative helium-cooled core designs are proposed, dedicated to the transmutation of actinides. LÄS MER

  7. 5. 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