The Chinese Academy of Engineering, one of the most important think tanks, revealed its 104 newly-elected academicians in 2019, including 75 Chinese and 29 foreigners. Prof. CHAI, a professor and dean of Central South University is a renowned expert of  environmental protection in  nonferrous metallurgical industry in China. Prof. Mark van Loosdrecht, a chair professor at Delft University of Technology, is a world famous researcher in biological wastewater treatment and recipient of various international major prizes including the Stockholm Water Prize and Lee Kuan Yew Water Prize.