Liquid solutions mechanical instability

Apart from liquid-liquid transitions, liquid-vapor transitions in aqueous electrolyte solutions have played a crucial role in debates on ionic criticality [142-144], The liquid-vapor transition is usually associated with a mechanical instability with diverging density fluctuations, while liquid-liquid transitions are associated with a material instability with diverging concentration fluctuations. This requires, however, that both regimes are well-separated. Their interference can lead to complex phase behavior with continuous transitions from liquid-liquid demixing to liquid-gas condensation [9, 145, 146]. It is then not trivial to define the order parameter [147-149]. 

The increase in the molar conductivity, corrected for viscosity effects, with increasing I2 content of MI (M = Me4N, Et4N, BU4N, or Na) in I2-DMF solutions and of Nal in I2-DMSO solutions has been attributed to the so-called relay conduction mechanism of 1 ions in I2 solutions."" These results support the proposal made earlier that the lower, but normal conductivities of Nal in liquid I2 are due to the thermal instability of Na I(l2)n- The formation of I3 has been studied spectrophotometrically in MeOH, Pr OH, Bu OH, MeCN, and DMSO" and in mixtures of these solvents both with and without water. 

The agglomeration of particles in a colloidal solution is due to instability and is responsible for most turbidity and sediment occurring in wine. This phenomenon, also known as flocculation, corresponds to the separation of the colloid into a colloidal crystal (gel) and a liquid. The end result is the formation of various types of flakes. In order to understand the particle agglomeration mechanism, which causes the solution, i.e. wine, to go from a clear state to a turbid state that is resolved by... 

Figure 10 Mechanisms of breakage of liquid films, (a) Fluctuation-wave-mechanism the film rupture results from growth of capillaty waves enhanced by attractive surface forces (92). (h) Pore-nudeation mechanism it is expected to be operative in very thin films, virtually representing two attached monolayers of amphiphilic molecules (99). (c) Solute-transport mechanism if a solute is transferred across the two surfaces of the liquid film due to gradients in the solute chemical potential, then Marangoni instability could appear and break the film...

A third mechanism of liquid-film breakage is observed when there is a transport of solute across the film (see Fig. 10c). This mechanism, investigated experimentally and theoretically by Ivanov and coworkers (109—111), was observed with emulsion systems (transfer of alcohols, acetic acid, and acetone across liquid films), but it could appear also in some asymmetric oil-water-air films. The diffusion transport of some solute across the film leads to the development of Marangoni instability, which manifests itself as... 

Mass detector. The liquid chromatographer s demand for a universal detector which overcomes some of the problems encountered with the RI detector, (such as poor sensitivity and temperature instability) led to the development about ten years ago of the mass detector described here. The transport detectors of the 1960s detected the solute by means of a flame ionization detector after removal of the solvent from the eluent stream. They were abandoned, owing to lack of sensitivity and mechanical problems associated with the moving belt or wire. The new mass detector is similar in principle, but here the eluent leaves the column and is pumped into a nebulizer, assisted by an air supply. The atomized liquid is passed into a heated evaporation column where all the solutes less volatile than the solvent are carried down the column as a cloud of fine particles. A light source and photomultiplier arranged at the bottom of the column, perpendicular to the flow, detect the cloud of particles. The output from the photomultiplier, which is proportional to the concentration, can be amplified and directed to a recorder or data system. 

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