Promoting caproate production using anaerobically digested sludge-derived biochar: Performances, mechanisms, and environmental impacts - Zhong-Fang Sun; Jie Gao; Chuan Chen; Kai-Kai Wu; Dong-Mei Liu; Shan-Shan Yang; De-Feng Xing; Ai-Jie Wang; Nan-Qi Ren; Lei Zhao (Bioresource Technology, 2025)