Partial Wetting Macroscopic Liquid Drops

We have to remind ourselves that 0 in this part because the liquid drops can be at equilibrium with oversaturated vapor only. A macroscopic drop means that the drop apex, H, is outside the range of surface forces (or disjoining pressure) action. Microscopic drops, that is, drops with the apex in the range of the disjoiiung pressure action, are considered in Section 2.2. 

However, even in the case of partial wetting, equilibrium droplets can exist on the solid snbstrate only in a limited interval of oversaturation, which is determined by the following inequality 0 P TI, or using Equation 2.2 in the following range of oversaturated pressure over the solid substrate. 

If is in the range 10 -10 dyn/cm, then the latter inequality takes the following form 

In the aforementioned narrow interval of oversaturation, the radii of the equilibrium drops change from infinity at p- p, to 

In the following text, we consider only two-dimensional drops for simplicity. Three-dimensional axisynunetric drops and menisci in cyUndrical capillaries are briefly considered towards the end of this section. 

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