Microemulsions micelles

As mentioned earlier, a great deal of literature has dealt with the properties of heterogeneous liquid systems such as microemulsions, micelles, vesicles, and lipid bilayers in photosynthetic processes [114,115,119]. At externally polarizable ITIES, the control on the Galvani potential difference offers an extra variable, which allows tuning reaction paths and rates. For instance, the rather high interfacial reactivity of photoexcited porphyrin species has proved to be able to promote processes such as the one shown in Fig. 3(b). The inhibition of back ET upon addition of hexacyanoferrate in the photoreaction of Fig. 17 is an example of a photosynthetic reaction at polarizable ITIES [87,166]. At Galvani potential differences close to 0 V, a direct redox reaction involving an equimolar ratio of the hexacyanoferrate couple and TCNQ features an uphill ET of approximately 0.10 eV (see Fig. 4). However, the excited state of the porphyrin heterodimer can readily inject an electron into TCNQ and subsequently receive an electron from ferrocyanide. For illumination at 543 nm (2.3 eV), the overall photoprocess corresponds to a 4% conversion efficiency. 

Fendler, J. H., Microemulsions, Micelles, and Vesicles for Membrane Mimetic Photochemistry, J. Phys. Chem., 1980, 84, 1485. 

An additional point is that relatively high concentrations of surfactant, oil and cosurfactant are often used in microemulsions. Thus the volume of the microemulsion pseudophase is large and droplet-bound reactants are therefore diluted. Generally speaking, rate enhancements increase in the sequence microemulsions < micelles < vesicles simply because of a decrease in the volume of the micellar or droplet pseudophase. 

The effectiveness of the method is most probably based on the fact that alkyl hypochlorite is formed at the oil/water interface where the cosurfactant alcohol resides. The oxidation that follows takes place either inside or on the surface of oil droplet. The rate of the reaction can result from a large hydrocarbon/water contact area permitting interaction between oil-soluble sulfide with interfacial cosurfactant that served as an intermediary. An extension ofthis procedure to mustard deactivation has also been proposed [20b]. Such systems could be also applied to the degradation of several environmentally contaminating materials The formation of microemulsions, micelles and vesicles is promoted by unfavourable interactions at the end sections of simple bilayer membranes. There is no simple theory of solute-solvent interactions. However, the formation of... 

Macrocyclic host molecules, medium-sized aggregates (microemulsions, micelles,vesicles, etc.) and mesoporous materials as catalysts... 

Understanding surfactant phase behavior is important because it controls physical properties such as rheology and freeze-thaw stability of formulations. It is also closely related to the ability to form and stabilize emulsions and microemulsions. Micelles, vesicles, mi-croemulsions and liquid crystal phases have all been used as delivery vehicles for perfumes or other active ingredients. 

The study of electron transfer (ET) at the polarized oil (0)/water (W) (or liquid/ liquid) interface is useful for understanding not only certain catal)rtic reactions in two-phase systems (e.g., liquid membranes, microemulsions, micelles, etc.) but also energy conversion processes occurring at biomembranes. In 1979, Samec etal. [1,2] reported, as the first example, an ET between ferrocene (Fc) in nitrobenzene (NB) and Fe(CN)6 in W ... 

Surfactant aggregates (microemulsions, micelles, monolayers, vesicles, and liquid crystals) are recently the subject of extensive basic and applied research, because of their inherently interesting chemistry, as well as their diverse technical applications in such fields as petroleum, agriculture, pharmaceuticals, and detergents. Some of the important systems which these aggregates may model are enzyme catalysis, membrane transport, and drug delivery. More practical uses for them are enhanced tertiary oil recovery, emulsion polymerization, and solubilization and detoxification of pesticides and other toxic organic chemicals. 

Electrosynthesis have been performed in microemulsions, micelles, and other multiphase systems. These studies exploit the benefit of ultrasound in the formation of the multiphase medium, and workers have tended not to look for any more subtle effect of ultrasound than just mechanical agitation. 

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