ISSN:
1573-935X
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Isotope exchange is reported for gaseous oxygen in contact with the following uranium compounds: α-Na2UO4, Β-Na2UO4, Na2U2O7, UO3(A), γ-UO3, α-UO2.94 and U3O8.; qualitative tests have also been done with UO2F2 and Cs2UO2Cl4. The times of half-exchange have been determined as functions of temperature for U3O8, α-UO2.94, Na2U2O7 and Β-Na2UO4; diffusion coefficients for oxygen have been calculated for UO3(A), γ-UO3, Na2U2O7, α-Na2UO4 and Β-Na2UO4. Activation energies have been deduced for diffusion and surface exchange. All the oxygen atoms in these compounds are equivalent as regards isotope exchange; the above activation energies increase with the U∶O ratio in some cases. Diffusion-limited exchange tends to show periodic oscillations in rate not ascribable to errors of measurement; a mechanism is proposed for this.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00526487
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