Multi-scale structural analysis of simulated nuclear waste glass samples using quantum beams

Okamoto, Yoshihiro  ; Nagai, Takayuki  ; Motokawa, Ryuhei   ; Kaneko, Koji   ; Oba, Yojiro  ; Shobu, Takahisa  ; Tominaga, Aki; Tanida, Hajime  ; Matsumura, Daiju   ; Tsuji, Takuya  ; Yoneda, Yasuhiro   

In order to evaluate the integrity of simulated nuclear waste glass samples, a multi-scale structural analysis system has been established, covering the range from local structure to implementation scale. Synchrotron radiation XAFS was used to investigate the local structure. Since XAFS has excellent elemental selectivity, it is useful for the analysis of waste components in the glass samples which are multi-component systems. In the short range structure, we prepared glass samples with substituted boron isotopes for neutron diffraction experiments and succeeded in obtaining diffraction data with high boron fraction for the first time. In the medium range structure, the influence of platinum group elements was evaluated by PDF analysis. Small-angle scattering experiments provided insight into the phase separation of borosilicate glasses. In addition, we attempted to apply stress-strain analysis to glass samples as structural information on the implementation scale. Through these structural analyses, we will evaluate the structural integrity of the modified glass samples being developed under the contract with the Agency for Natural Resources and Energy.