National standard research on the minimum allowable values of energy efficiency and energy efficiency grades for air cleanersJin Huang, Hao Shen, Ling Lin, Kang Wang, Baozhu Wang, Xianfei Yang, Wei Wu, Xiaoxin Zhang and Zhenhai LiE3S Web Conf., 118 (2019) 02018DOI: https://doi.org/10.1051/e3sconf/201911802018