Beam‐induced oxidation of monomeric U(IV) species. (26th December 2012)

• Record Type: Journal Article
• Authors: Alessi, Daniel S.; Uster, Benjamin; Borca, Camelia N.; Grolimund, Daniel; Bernier‐Latmani, Rizlan
• Is Part Of: Journal of synchrotron radiation. Volume 20:Part 1(2013)
• Page Start: 197
• Page End: 199
• Publication Date: 2012-12-26
• Subjects: Synchrotron radiation -- Periodicals; Free electron lasers -- Periodicals; 539.73505
• DOI: 10.1107/S0909049512041763
• Languages: English
• ISSNs: 0909-0495

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <p>Uranium <italic>L</italic>_III‐edge X‐ray absorption spectroscopy is often used to probe the oxidation state and coordination of uranium in environmental samples, and micrometre‐sized beams can be used to spatially map the distribution of uranium relative to other elements. Here a variety of uranium‐containing environmental samples are analyzed at both microbeam and larger beam sizes to determine whether reoxidation of U(IV) occurred. Monomeric U(IV), a recently discovered product of U(VI) reduction by microbes and certain iron‐bearing minerals at uranium‐contaminated field sites, was found to be reoxidized during microbeam (3 µm × 2 µm) analysis of biomass and sediments containing the species but not at larger beam sizes. Thus, care must be taken when using X‐ray microprobes to analyze samples containing monomeric U(IV).</p> </abstract>