The project was supported by the Ningbo Municipal Natural Science Foundation, China2010A610164,2010A610187;Ningbo Social Development Project, China2012C5002;K. C. Wong Magna Fund of Ningbo University, China.宁波市自然科学基金2010A610164,2010A610187;宁波市重大择优委托项目2012C5002;宁波大学王宽城基金