Static wetting of carbon nanocones contact angle hysteresis at nanometer scale

1 Static wetting of carbon nanocones contact angle hysteresis at nanometer scale 

An example of a force curve is reported in Fig. 9.11b, in the case of a conical tip with a 120 nm long nanotube protruding at its extremity, dipped in heptadecane. After contact with the liquid interface, a short plateau corresponding to the cylindrical nanotube 

The last part of the separation process is important in the framework of the elasticity of meniscus since it corresponds to the stretching of the meniscus. The slope of the curve is a direct determination of the meniscus spring constant. In Fig. 9.12 is reported this part for two different liquids (heptadecane and glycerol). The spring constant values determined with several tips for each liquid are heptadecane = 8 3 mN/m and kgiyceroi = 18 3 mN/m. 

For both liquids we find that k/y = 0, 3 0.1. Interestingly these values are more than 10 times smaller than the one obtained with nanomeniscus between a tip and a surface (see section 9.3.1.1). A comparison with Eq. 9.10 giving the meniscus spring constant provides a way to estimate the macroscopic characteristic length of the meniscus. Due to the fact that this parameter is involved in a logarithmic term and given the uncertainties in the experimental 

In order to quantitatively investigate the strong defect regime, which is the most frequent situation, we proposed a simpIiFied model for the pinning on a single defect. Considering the case of a 

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