Funding for this research was provided by:
National Natural Science Foundation of China (71704092)
Tsinghua University (2017THZWYY08)
Tsinghua University’s Center for Industrial Development and Environmental Governance, Summer Institute for China’s Green Innovators, and Tang Scholar
Received: 19 November 2018
Accepted: 28 August 2019
First Online: 9 September 2019
: The authors declare no competing interests.