This work was supported by the National Natural Science Foundation of China (Nos. 81402221 and 51273216), the Research Fund for the Doctoral Program of Higher Education of China (No. 20130171120077), the Science and Technology Program of Guangzhou, China (No. 201707010108), the Guangdong Innovative Research Team Program (No. 2009010057), and the Science and Technology Planning Project of Guangzhou (No. 201610010006), the Science and Technology Planning project of Guangdong Province (No. 20153900042020319) and Natural Science Foundation of Guangdong Province (No. 2016A030313819).
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