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Last name: DUMAS
First name: Thomas
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Abstract [H 7 O 3 ] 4 [Tc 20 O 68 ] ⋅ 4H 2 O [ 1 ] was prepared from an aqueous Tc 2 O 7 solution concentrated over anhydrous H 2 SO 4 . [Tc 20 O 68 ] 4− is the first polyanionic species to be reported for Tc. The unit cell contains one centrosymmetric [Tc 20 O 68 ] 4− polyanion as well as hydronium ions and water molecules. The core of the...
20 kHz sonication of amorphous and crystalline UO 3 powder in pure water under Ar/(10%)CO atmosphere yields intrinsic uranium( vi ) colloids exhibiting a schoepite-like crystallographic structure.
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Solubility, migration, and bioavailability of plutonium is lacunar because experimental evidences are missing. We report here on X-ray Absorption Spectroscopy of plutonium in natural seawater. The observed valence state is +IV and its speciation corresponds to PuO2 type colloids. Furthermore, aging of the solution shows a gradient of ordering...