Comprehensive evaluation of polycyclic aromatic units in three liquefaction-derived heavy fractions from Zhunnan lignite

Guang‐Hui Liu, Yong Gao, Yanjun Li, Aimin Wang, Xiaoyong Fan, Xian‐Yong Wei, Yu-Hong Kang, Hua-Rui Hao, Zhan‐Ku Li, Hongcun Bai