Interfacial corrugations

Recently, these authors have treated specific adsorption at corrugated liquid-liquid interfaces [39] however, because of the complicated mathematics involved this work does not fall under the heading simple models. Also, Urbakh et al. [40] have extended the results for the interfacial capacity to the nonlinear region. 

The bilayer morphology of thin asymmetric films of may be unstable. A regularly corrugated surface structure of the films was ascribed to spinodal transition into a laterally phase separated structure, where the surface morphology depended on the polymer incompatibility and the interfacial interactions [347, 348]. Recently, the phase separation and dewetting of thin films of a weakly incompatible blend of deuterated PS and poly(p-methylstyrene) have been monitored by SFM [349, 350]. Starting from a bilayer structure, after 454 h at T= 154 °C the film came to the final dewetting state where mesoscopic drops of... 

The interface is described as before, using the approximation of smooth corrugations. The two electrolyte solutions are characterized by the solvent dielectric constants, e and si, and Debye lengths, k and In addition to the interfacial tension term, the free-energy functional now has two new terms. These are the electrostatic energy, Fg, and the term responsible for the entropy of a dilute electrolyte, Fg, so that... 

The concept of capillary waves can be used to explain how the surface roughness increases the interfacial capacity beyond the Verwey-Niessen value. For this purpose, Pedna and Badiali [82] have solved the linear Poisson-Boltzmann equation across the interface between two solutions vyith different dielectric constants and Debye lengths separated by a corrugated surface. A major difficulty is the boundary condition at the rough interface. 

Film fill consists of corrugated or rippled sheets that subdivide the water and provide interfacial area. These sheets are assembled into packs that are installed vertically and stacked at offset angles. This is the more efficient of the two types of fill, but it is more difficult to install properly. Solids are more likely to deposit in the fill, and maldistribution of water is more likely. 

The boundary condition is controlled by the extent to which the liquid feels a spatial corrugation in the surface energy of the solid. This depends on a number of interfacial parameters, including the strength of the liquid-liquid and liquid-solid interactions, the commensurability of the substrate and the liquid densities, characteristic sizes, and also the roughness of the interface. In order to quantify the slippage effect, the slip length. 

Actually, in 2004, Komyshev and Urbakh proposed a theoretical model to show that the dependence of the direct energy transfer signal on the potential drop across the interface can give valuable information about the interfacial dynamic corrugations and pattern formation on the length scales between 1 and 10 nm [36]. 

Some cooling towers operate with natural draft. This is possible because the warmer, humid air inside the tower is less dense than the colder, drier outside air. Many such towers are hyperbolic and may require an overall height of 220 ft. The fill used in such a column must be quite open to avoid any significant pressure drop. Such fill can have a tee- or vee-shaped cross section molded from perforated plastic sheets. Corrugated sheets made of asbestos and cement are popular in large natural draft towers. A ceramic cellular block that is stacked into the tower also is used. These fills, however, provide a small interfacial area per cubic foot so mass transfer is rather low per foot of packed depth. 

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