1. Shaanxi Key Laboratory of Photoelectric Functional Materials and Devices School of Materials and Chemical Engineering Xi'an Technological University Xi'an 710021 P. R. China
2. Shaanxi Provincial Key Laboratory of Papermaking Technology and Specialty Paper Development College of Bioresource Chemical and Materials Engineering Shaanxi University of Science & Technology Xi'an 710021 P. R. China
3. State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation School of New Energy and Materials Southwest Petroleum University Chengdu 610500 P. R. China