Influence of sand grain diameter and wind velocity on lift-off velocities of sand particles Tian-Li Bo, Xiao-Jing Zheng, Shao-Zhen Duan and Yi-Rui Liang Eur. Phys. J. E, 36 5 (2013) 50 Published online: 24 May 2013 DOI: 10.1140/epje/i2013-13050-y