Free occupying mechanism of simulated tetravalent waste ions in Gd2Zr2O7 and performance evaluation of the waste forms. - Zuo, Shibing; He, Yang; You, Yi; Shu, Xiaoyan; Wen, Mingfen; Lu, Yuexiang; Duan, Tao; Chen, Jing; Luo, Fen; Dong, Faqin; Lu, Xirui (Journal of the American Ceramic Society, 2023)