Catalytic liquefaction of pig manure in ethanol: Yield and properties of bio-oil - Qingdan Wu; Siyu Huang; Qianlan Li; Xiaochen Zheng; Wei Liu; Ruirui Zhu; Jialong Tang; Binbin Dai; Yingying Mo; Likun Zhan; Jie Xiong; Zhihua Xiao (Biomass and Bioenergy, 2026)