Adsorption at interface

Ionic species present in liquids undergo adsorption at interfaces such that predominantly one sign of charge is more strongly bound at the contacted surface than the other. This results in a bound layer close to the surface farther from which is a diffuse layer having a net countercharge. This two-layer... 

Schofield Phil. Mag. March, 1926) has recently verified this relation by direct experiment. In order to appreciate the significance of this result, it is necessary to consider in more detail the electrical potential difference V and the manner in which it arises. Instead of regarding the phenomenon from the point of view of the Gibbs equation, it has been, until recently, more usual to discuss the subject of electro-capillarity from the conceptions developed by Helmholtz and Lippmann. These views, together with the theory of electrolytic solution pressure advanced by Nemst, are not in reality incompatible with the principles of adsorption at interfaces as laid down by Gibbs. 

Using this approach, a model can be developed by considering the chemical potentials of the individual surfactant components. Here, we consider only the region where the adsorbed monolayer is "saturated" with surfactant (for example, at or above the cmc) and where no "bulk-like" water is present at the interface. Under these conditions the sum of the surface mole fractions of surfactant is assumed to equal unity. This approach diverges from standard treatments of adsorption at interfaces (see ref 28) in that the solvent is not explicitly Included in the treatment. While the "residual" solvent at the interface can clearly effect the surface free energy of the system, we now consider these effects to be accounted for in the standard chemical potentials at the surface and in the nonideal net interaction parameter in the mixed pseudo-phase. 

Emulsification Adsorption at interfaces, Sausages, bologna, soups, Muscle proteins, egg... 

Cayias, J.L. Schechter, R.S. Wade, W.H. The Measurement of Low Interfacial Tension via the Spinning Drop Technique in Adsorption at Interfaces, Mittal, K.L. (Ed.), American Chemical Society Washington, 1975, pp. 234-247. 

Micellar Liquid Chromatography (MLC) uses surfactant solutions as mobile phases for reversed phase liquid chromatography. The two main properties of surfactant molecules, as related to chromatography, are micelle formation and adsorption at interfaces. The micelles play the role of the organic modifier, so their influence on retention has been extensively studied (1). At surfactant concentrations above the critical micellar concentration (CMC), micelles are present and the amount of free surfactant is essentially... 

Though most studies on protein adsorption at interfaces have been conducted in solutions having a single well characterized protein, evidence has emerged in recent years that film properties in mixed protein systems are much more complex than in single protein systems. 

The De Donder inequality for systems with adsorption at interfaces is—... 

Many different isotherms have been derived for molecular adsorption at interfaces, including the liquid gas, liquid liquid, and liquid solid interfaces. Some of these isotherms can be shown to be approximate versions of the general isotherm derived here. 

Ling, C.-S. Drost-Hansen, W. (1975). DTA study of water in porous glass. ACS Symp. Series Number 8 Adsorption at interfaces. ACS, Washington, DC, 129-156. 

Conway, B. E. (1976), Hydrophobic and Electrostatic Interactions in Adsorption at Interfaces Relation to the Nature of Liquid Surface, Croat. Chem. Acta 48, 573-596. 

Osseo-Asare, K., D. W. Fuerstenau, and R. H. Ottewill, in Adsorption at Interfaces, K. L. Mittal (Ed.), Symposium Series No. 8, American Chemical Society, Washington, DC,... 

Improved understanding of the mechanism, energetics, and structure of the bonding of water to surfaces is needed. Such information is a key to fundamental clarification of the interfacial structure at solid-liquid surfaces. Poor understanding of the thermodynamics of polymer adsorption at interfaces is impeding scientific progress on corrosion inhibition, colloidal stability, alteration of membrane selectivity, and electrocrystallization additives. 

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