In addition, the indenter Bafilomycin A1 nmr radius has a remarkable influence on the force-displacement curve. As the

indenter radius increases, the critical load and the critical indentation depth also increase. Acknowledgements We acknowledge the financial support provided by the Fundamental Research Funds for the Natural Science Basic Research Plan in Shaanxi Province of China (grant no. 2013JM7017), subsequently by the National Natural Science Foundations of China (grant no. 51205302 and no. 50903017) and the Central Universities in Xidian University (grant no. K5051304006). We also would like to thank all the reviewers for their comments and kind suggestions to our manuscript and all the editors for their careful corrections on the final version of the article. References 1. Geim A, Novoselov K: The rise of graphene. Selleck GSK872 Nat Mater 2007, 6:183–191.CrossRef 2. Wang W, Hao Y, Yi C, Ji X, Niu X: Relaxation properties of graphene nanoribbons at different ambient temperatures: a molecular dynamics. Acta Phys Sin

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