Wetting properties effect water-surface effects

The wetting properties of water can be improved by surfactants. Fires of plastics, rubbers, wood, coal-dust, etc. are fought more effectively by such a wet water . A film-forming foam, called light water , is especially useful on the surface of low-density liquids. 

Designing effective water-repellent, water-resistant, or waterproof fabrics to provide protection in inclement weather or during certain outdoor activities requires an understanding of the chemical and physical properties of water. Whether you are sailing in wind-driven rain, hiking in a downpour, or sitting on a wet surface, chemistry can keep you dry ... 

The visualization study of Yang et al. further revealed the profound effects of wetting properties of gas channel walls. In a gas channel surrounded by mixed hydrophilic channel surfaces and hydro-phobic GDL surface, it was found that water conden-... 

The wetting properties of the particles play a crucial role in flotation. We have already discussed the equilibrium position of a particle in the water-air interface (Section 7.2.2). The higher the contact angle the more stably a particle is attached to the bubble (Eq. 7.19) and the more likely it will be incorporated into the froth. Some minerals naturally have a hydrophobic surface and thus a high flotation efficiency. For other minerals surfactants are used to improve the separation. These are called collectors, which adsorb selectively on the mineral and render its surface hydrophobic. Activators support the collectors. Depressants reduce the collector s effect. Frothing agents increase the stability of the foam. 

Garrett came to the conclusion that most important for the synergy action of an oil-particle antifoam seems to be the ability of the particles to facilitate the appearance of oil droplets into the air/water surface. However, the sizes of the antifoam oil/particle composites should be sufficiently small to ensure a high probability of presence in a given foam film, but not so small to slow down the film drainage and suppress antifoaming effect. It order to possess such properties the particles should be hydrophobic but not completely wetted by the oil. The contact angle 9ow at the oil/water interface should satisfy the condition [20]... 

The advantageous properties of magnesium hydroxide were made use of in another investigation of surface-water treatment where dolomite was applied as coagulant [4 ]. Thus, soft-burned and wet-slaking dolomite appeared to effectively... 

Capillary sealing effects are controlled by wetting phenomena which, for hydrocarbons in general, are poorly constrained. In real sub-surface situations, the assumption of a water-wet seal is reasonable for an initially hydrocarbon-free seal. This may be less likely in dynamic situations where capillary seals may leak periodically in the presence of active charge. The wetting properties of seals may change through time an initially water-wet seal may evolve into a hydrocarbon-wet seal, due to the adsorption of a variety of compounds from crude oil, such as asphaltenes (Anderson, 1986). This may ultimately result in a top seal which has no capillary seal capacity and leaks via two-phase flow. 

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