Interfacial energy cell-liquid

Y j, = cell-liquid interfacial free energy = cell-polymer interfacial free energy... 

Interfacial energy between two solids can thus be extremely low, if they have different composition but similar crystal lattices in their symmetries and their cell parameters. We can note that this is the origin of the phenomena of heterogenous primary nucleation starting from the liquid phases, whose ultimate demonstration is the epitaxy. This interfacial energy can on the contrary be very high if the networks are very different in molar volumes and from the crystallographic point of view. 

There are large cations in these cells, e.g., tetra-alkylammonium cations in the organic phase and the interfacial ion exchange involves only so-called critical ions, here X and LX ions are practically not transferred through the organic phase. Both liquid interfaces are reversible with respect to the appropriate anion, X or L. EMF is, in practice, also influenced by the diffusion potential in the organic phase, and in the case of cells of the type in Scheme 11 - by the difference of standard transfer energies of both ions (Section III.A)... 

Thus it would seem that the actual intrinsic surface tension of biological liquids, i.e. the one that plays a role in the interactions between cells among one another, and between cells and biopolymers, must be close to that of serum or plasma ultrafiltrates, i.e. y 70 dyn/cm or the intrinsic interfacial free energy of the interstitial mammalian liquid, serum or plasma, or AF —140 ergs/cm2. 

The adsorption of a surfactant at an interface between CO2 and a second fluid, such as water, may be determined directly from measurement of the interfacial tension (change in Gibbs free energy with surface area), y, versus surfactant concentration. A novel tandem variable-volume pendant drop tensiometer has been developed to measure equilibrium and dynamic values of y as a function ofT.p and time (Figure 2.4-1) [21]. An organic [21] or aqueous phase [18] is preequilibrated with CO2 in the first variable-volume cell (drop-phase cell). A droplet of this liquid is injected into the second variable-volume cell, with two windows at 180° mounted on a diameter, containing either pure CO2 or CO2 and surfactant. 

A. Heller and B. Miller, Photoelectrochemical solar cells Chemistry of the semiconductor-liquid junction, Chap. 12 in Interfacial Photoprocesses Energy Conversion and Synthesis, Advances in Chemistry Series, 184, Ed. by M. S. Wrighton, American Chemical Society, Washington, D.C., 1980. 

Vectorial charge transfer at the interface between two dielectric media is an important stage in bioelectrochemi-cal processes such as those mediated by energy transducing membranes [1,2]. Boundary membranes play a key role in the cells of all contemporary organisms, and simple models of membrane function are therefore of considerable interest. The interface of two immiscible liquids has been widely used for this purpose. For example, the fundamental processes of photosynthesis [3], membrane fusion [4], ion pumping [5] and electron transport [6,7] have all been investigated in such interfacial systems. 

The chemical nature of the chain, as reflected in the crystal stmcture and in the disordered chain conformation, will strongly influence the interfacial stmcture. At one extreme, we can conceive of a chain for which there is a minimal expenditure of free energy on making a bend. In this case, adjacent re-entry will predominate. For chains whose axes are positioned far from one another in the unit cell, as in the a-helical polypeptides, or have extended conformations in the disordered liquid state, as in cellulose and its derivatives, folding of any type including adjacent re-entry will be minimal. 

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