NSF of ChinaNational Natural Science Foundation of China (NSFC) [11161015, 11371367, 11361012]; PSF of China [2012M512162, 2013T60934]; NSF of Hunan Province [11JJ900, 12JJ9001, 13JJ4098]; Education Foundation of Hunan Province [12C0541, 12C0361, 13C084]; Construct Program of the Key Discipline in Hunan Province