title: Collective structural changes in vermiculite clay suspensions induced by cesium ions.
abstract: Following the Fukushima Daiichi nuclear disaster in 2011, Cs radioisotopes have been dispersed over a wide area. Most of the Cs has remained on the surface of the soil because Cs(+) is strongly adsorbed in the interlayer spaces of soil clays, particularly vermiculite. We have investigated the microscopic structure of an aqueous suspension of vermiculite clay over a wide length scale (1-1000 Å) by small-angle X-ray scattering. We determined the effect of the adsorption behavior of Cs(+) on the structural changes in the clay. It was found that the abruption of the clay sheets was induced by the localization of Cs(+) at the interlayer. This work provides important information for predicting the environmental fate of radioactive Cs in polluted areas, and for developing methods to extract Cs from the soil and reduce radioactivity.
authors.affiliation: Actinide Coordination Chemistry Group, Quantum Beam Science Center (QuBS), Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan.
authors.forename: Ryuhei
authors.initials: R
authors.lastname: Motokawa
authors.affiliation: 1] Neutron Science Division, Institute of Material Structure Science, High Energy Accelerator Research Organization, 203-1 Shirakata, Tokai, Ibaraki 319-1106, Japan [2] Department of Material Structure Science, The Graduate University for Advanced Studies (SOKENDAI), 203-1 Shirakata, Tokai, Ibaraki 319-1106, Japan.
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Endo
authors.affiliation: Central Research Institute of the Electric Power Industry, Abiko, Chiba 270-1194, Japan.
authors.forename: Shingo
authors.initials: S
authors.lastname: Yokoyama
authors.affiliation: Graduate School of Science and Engineering, Yamagata University, Yonezawa, Yamagata 992-8510, Japan.
authors.forename: Shotaro
authors.initials: S
authors.lastname: Nishitsuji
authors.affiliation: Actinide Coordination Chemistry Group, Quantum Beam Science Center (QuBS), Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan.
authors.forename: Tohru
authors.initials: T
authors.lastname: Kobayashi
authors.affiliation: Actinide Coordination Chemistry Group, Quantum Beam Science Center (QuBS), Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan.
authors.forename: Shinichi
authors.initials: S
authors.lastname: Suzuki
authors.affiliation: Actinide Coordination Chemistry Group, Quantum Beam Science Center (QuBS), Japan Atomic Energy Agency (JAEA), Tokai, Ibaraki 319-1195, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Yaita