草叶表面的一维非对称界面摩擦特性

Investigation of One-Dimensional Asymmetric Friction on Interfaces of Plant Leaf

用扫描电子显微镜观察黑麦草叶表面的微观结构,研究液滴与表界面的一维非对称摩擦特性.结果表明:黑麦草叶表面具有不等周期的锯齿结构阵列,且锯齿结构具有特定的取向特征;黑麦草叶表面对液滴产生一维摩擦特性的主要原因是由于取向的锯齿结构在液滴运动时形成了方向依赖的非对称三相接触线导致不同的接触黏滞,证实了微观结构与界面摩擦特性的依赖关系.

The authors observed the microstructure of wild grass leaf by scanning electron microscopy and found there were different periodic ratchet-structure arrangements and the ratchet-structure could be oriented in a certain direction.We studied the one-dimensional contrast friction between the water drop and surface interface of leaf via the drop moved along the contrasting directions.This investigation indicates one-dimensional contrast friction can be generated due to the different three-phase contact line resulted from the oriented ratchet-structure at the moment of drop moving along the contrasting directions.It demonstrates thereby the important relationship between microstructure and friction.