Thermal aspects dispersion

For general aspects on sonochemistry the reader is referred to references [174,180], and for cavitation to references [175,186]. Cordemans [187] has briefly reviewed the use of (ultra)sound in the chemical industry. Typical applications include thermally induced polymer cross-linking, dispersion of Ti02 pigments in paints, and stabilisation of emulsions. High power ultrasonic waves allow rapid in situ copolymerisation and compatibilisation of immiscible polymer melt blends. Roberts [170] has reviewed high-intensity ultrasonics, cavitation and relevant parameters (frequency, intensity,... 

It is well known that water dispersions of amphiphile molecules may undergo different phase transitions when the temperature or composition are varied [e.g. 430,431]. These phase transitions have been studied systematically for some of the systems [e.g. 432,433]. Occurrence of phase transitions in monolayers of amphiphile molecules at the air/water interface [434] and in bilayer lipid membranes [435] has also been reported. The chainmelting phase transition [430,431,434,436] found both for water dispersions and insoluble monolayers of amphiphile molecules is of special interest for biology and medicine. It was shown that foam bilayers (NBF) consist of two mutually adsorbed densely packed monolayers of amphiphile molecules which are in contact with a gas phase. Balmbra et. al. [437J and Sidorova et. al. [438] were among the first to notice the structural correspondence between foam bilayers and lamellar mesomorphic phases. In this respect it is of interest to establsih the thermal transition in amphiphile bilayers. Exerowa et. al. [384] have been the first to report such transitions in foam bilayers from phospholipids and studied them in various aspects [386,387,439-442]. This was made possible by combining the microscopic foam film with the hole-nucleation theory of stability of bilayer of Kashchiev-Exerowa [300,402,403]. Thus, the most suitable dependence for phase transitions in bilayers were established. 

Tolstoguzov, V.B. (2000b). Foods as dispersed systems. Thermodynamic aspects of composition-property relationship in formulated food. J. Thermal Anal. Calorimetry, 61, 397-409. Tolstoguzov, V.B. (1999). The role of water in intermolecular interactions in food. In Y.H. Roos, R.B. Leslie and P.J. Lillford (Eds.), Water Management in the Design and Distribution of Quality Foods. (Proceedings ISOPOW 7 Symposium), Technomic Publishing Company, Lancaster, PA, pp. 199-233. 

There is no doubt that the extensive but dispersed literature concerned with decompositions of solids is in need of review. The nimiber of comprehensive surveys of this important, active and well-defined subject area that have been published in the last fifty years (the effective life-time of the topic) is remarkably small. Even reviews of more restricted aspects, such as the thermal properties of particular groups of reactants, are surprisingly few in number. 

These two approaches for the determination of the excess chemical potential of the substance of the dispersed phase, Ap,. and Ap,., are used in the analysis of different aspects related to the equilibrium state of disperse systems. The first approach was utilized in Chapter 1,3 in the derivation of the Kelvin equation, when we examined the equilibrium between the dispersed particle and the continuous phase. The second approach accounts for the involvement of particles in thermal motion and therefore envisions both generation and disappearance of a particle as a whole, and thus allows one to describe the equilibrium between particles of different sizes. The equilibrium particle size distribution corresponds to a condition of constant chemical potential for particles of different sizes (including those of molecular dimensions), i.e. Ap/ = const. The expression for the equilibrium number of particles of a given radius2, r, can be obtained from eq. (IV. 12) as... 

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