Cohesion free energy

The equilibrium situation which exists after a liquid drop is brought into contact with a smooth homogeneous substrate depends on the balance between adhesion and cohesion free energies involved. Three cases can be identified ... 

Free energy of adhesion Free energy of cohesion Free energy of spreading Glass transition temperature Rate of energy input to filament Volume... 

Table 24.3 Bond nature (m) dependence of the ratios of surface energy density, (yjs). unit area and surface cohesion (free energy), (yj), per atom with respect to the bulk values...

Ultimately, the surface energy is used to produce a cohesive body during sintering. As such, surface energy, which is also referred to as surface tension, y, is obviously very important in ceramic powder processing. Surface tension causes liquids to fonn spherical drops, and allows solids to preferentially adsorb atoms to lower tire free energy of tire system. Also, surface tension creates pressure differences and chemical potential differences across curved surfaces tlrat cause matter to move. 

The surface free energy y is related to the cohesive energy of the solid, AHcoh, and to the number of bonds between an atom and its nearest neighbors that had to be broken to create the surface ... 

Cohesive energy (or free energy) density parameter (Chaps. XII and XIII). 

The data for influence of solvents on oxidation propanthiole by chlorine dioxide are satisfactorily generalized by means of five parameters equation according to principles of Linear Free Energies Relationships (LFER). An essential role plays the density of media cohesion energy, that bears out radical process nature. 

An interesting consequence of Eq. (2.10) is that two crystal structures with different cohesive energies can have the same Gibbs free energy if A coh — P AT. Comparing this condition with Eq. (2.11), you can see that... 

Performance Cohesive and adhesive properties, surface free energy, and water uptake behavior affect disintegration and dissolution behavior... 

This study presents an experimental approach for measuring the cohesive energies in condensed lipid monolayers which avoids the difficulty of measuring extremely low values of tt. The approach depends on evaluating the free energy of desorption (or adsorption) of condensed films and comparing this value with the free energy of desorption of the film in the ideal-gas state. 

To evaluate the free energy of cohesion in the hydrocarbon region of the monolayer, Wc, it is necessary only to obtain the value of W0, the free energy of desorption of the hydrocarbon in the absence of interac-... 

Measurement of the free energies of monolayer desorption from the rates of desorption depends on whether equilibrium exists between the monolayer and a thin region of solution immediately beneath the film. The relation which tests this condition (Equation 8) must correctly predict the dependence of the rate constant for desorption, k8, on 7r. For the sulfate, phosphonate, and carboxyl films in this study Equation 8 is obeyed within the range of experimental error (2 to 5%). Therefore, it is reasonable to assume that the necessary equilibrium condition does exist. The cohesive forces in the monolayer follow directly from the evaluation of the free energies of desorption. 

Implicit in the determination of Wr, the cohesive energy in the hydrocarbon region of the long-chain monolayer, is the assumption that W0, the free energy of desorption for one —CH2— group, obtained with relatively short hydrocarbon chains, is independent of the length of the hydrocarbon moiety. The validity of this assumption can be checked for sulfate films where W(. may be obtained from desorption studies as... 

The surface tension of a pure liquid is a direct measure of the free energy or cohesion. For a solid, the surface free energy, which has the same dimensions as surface tension, is the measure of free energy of cohesion. Thus, for Substance i... 

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