Figure 26

Fig. 26: Oxidation states of U.

a) µ-XANES analysis of U-standards and Chernobyl particles (a: metallic U, b: Chernobyl West particle, c: UO₂, d: Chernobyl North, e: U₃O₈, f: UO₂Ac₂).

b) Inflection point energy versus oxidation states of uranium in the analysed particles. The inflection point energies of the Chernobyl West particles show the oxidation state +2.5±0.5, while for particles collected to the North of the reactor the oxidation state was +5±0.5.

c) XANES line scan of Chernobyl West particle having reduced core and oxidised surface layer.