作者机构:[1]Department of Geological Engineering, Southwest Jiaotong University, Chengdu 610031, China
相关基金:Acknowledgements This research was supported by the National Nature Science Foundation of China (Grant Nos. 41172260, 41372292, 5 l 108393), the National Basic Research Program of China (Grant No. 2008CB425801), and the Specialized Research Fund for the Doctoral Program of Higher Education (No. 20110184110018) as well as the Doctoral Student Innovation Fund of South-west Jiaotong University.