Energy barriers composite surface

It is not possible to obtain composite surfaces for 6 less than 90° for our model. (This is not true for all surfaces-for example, one composed of parallel fibers.) Accordingly, there is no drastic decrease in hysteresis in Figure 11 as is observed in Figure 10. On the other hand, when 6 is less than 90°, there is a surface roughness at which surface wicking tends to occur. This occurs when = 0. Whether or not wicking actually occurs depends on the vibrations in the drop and on the nature of the energy barriers. 

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