Interfacial pressure chloride system

It may be noted that for non-polar CS2/hexane system [34], the development of osmotic pressure is out of question. Even for aqueous solutions of electrolyte-water system, experiments [35] with a U-tube system rule out the possibility of generation of oscillations due to osmotic pressure. It has also been reported [35] that experiments with aqueous solutions of electrolyte/aqueous solution of surfactant cetyl pyridinium chloride system (the latter kept in the outer vessel) and the system without surfactant show that the interfacial effects are also not significant since the amplitude of oscillations is unaffected. 

It is interesting to employ the system consisting of mixed adsorbed film of 1-pctadecanol and dodecylammonium chloride because the former shows the phase transition from an expanded to a condensed state ( ). The interfacial tension was measured as a function of temperature at various bulk concentrations under atmospheric pressure and the molecular interaction between film-forming components was considered. 

The most pertinent effects of ultrasound in solid-liquid reactions are mechanical, which are attributed to symmetrical and/or asymmetrical cavitation. Symmetrical cavitation (the type encountered in homogeneous systems) leads to localized areas of high temperatures and pressures and also to shock waves that can create microscopic turbulence (Elder, 1959). As a result, mass transfer rates are considerably enhanced. For example, Hagenson and Doraiswamy (1998) observed a twofold increase in the intrinsic mass transfer coefficient in the reaction between benzyl chloride (liquid) and sodium sulfide (solid). In addition, a decrease in particle size and therefore an increase in the interfacial surface area appears to be a common feature of ultrasound-assisted solid-liquid reactions (Suslick et al., 1987 Ratoarinoro et al., 1992, 1995 Hagenson and Doraiswamy, 1998). 

When measuring the surface pressure isotherms, it is desirable that the values of the interfacial tension are not time-dependent. In this case, in the interfacial region a state is reached close to the equilibrium for the surfactant distribution between the phases [55]." If the surfactant is soluble in both phases, one should be careful in calculating the surface excess in such systems, and the surfactant distribution coefficient should be determined independently. For instance, trioctylmethylammonium chloride (Oct3MeNCl) in the benzene-water system has a distribution coefficient of the order of 10 [57]. The surface pressure isotherms at the benzene-water interface are almost independent of the phase in which Oct3MeNCl is dissolved. It means that in both cases Oct3MeNCl is almost completely located in the benzene phase, i.e. the surfactant distribution equilibrium is reached at the interface. Apparently, the anomalies in the... 

The addition of a surfactant to systems with particle monolayers at oil/ water interfaces allows us to determine the way in which the monolayer collapse pressure, II,., varies with the interfacial tension, of the (particle-free) oil/water interface [23]. This, in turn, can give us some feel for the physical origin of particle monolayer collapse. Quite remarkably, we hnd that there is a very close correspondence between He and yow, as seen in Fig. 23. The tensions of the oil/water interface have been varied by addition of a range of concentrations of fom different smfactants (including anionic, cationic, and nonionic), namely CTAB, SDS, cetylpyridinium chloride (CPC), and the pure sugar surfactant decyl )8-glucoside (DBG). 

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