1. 1Key Laboratory of Oil and Gas Fine Chemicals, Ministry of Education and Xinjiang Uyghur Autonomous Region, Xinjiang University, Urumqi 830046, P.R. China
2. 2Key Laboratory of Oil and Gas Fine Chemicals, Ministry of Education and Xinjiang Uyghur Autonomous Region, Xinjiang University, Urumqi 830046, P.R. China, Tel.: +86 991 8581018, Fax: +86 991 8582807