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Yang Zhihua started working at Tsinghua University in 1959 after graduating from the same university. He worked at the Department of Civil Engineering, the Deparment of Chemical Engineering and the Institute of Nuclear Energy successively. In 1981, he was transferred to the Division of Environmental Chemistry within the Department of Environmental Engineering where his research focus included nuclear reaction water supply and drainage, design and construction of nulcear three wastes treatment project, urban sewage treatment, dye water recycling, sludge heavy meal recovery, etc. He retired as a professor in 1996.