Enhanced volatile fatty acids production from anaerobic co-fermentation of waste activated sludge and food waste via electrochemical pretreatment: Performance of carbon source utilization, safety and economic analysis - Qingshan Lin; Lihong Wang; Kejie He; Li Li; Shuting Liang; Yeqing Li; Zichong Zhu; Gang Guo (Journal of Water Process Engineering, 2026)