Showing papers on "Gibbs–Duhem equation published in 1989"
TL;DR: It is argued that the Gibbs-Duhem equation alone cannot be used for deriving conclusions about the pressure gradient in membrane permeation, and Prigogine's theorem is invalid in this approach to describing membranes permeation.
Abstract: It is argued that the Gibbs-Duhem equation alone cannot be used for deriving conclusions about the pressure gradient in membrane permeation. Statements regarding spatial variation of pressure in conjunction with chemical potential gradients of the components can legitimately be drawn from an equation that results from a combination of the G-D equation and the mechanical equilibrium equation. The derived equation has been applied here for explaining the mechanics of osmosis. In a further application, the frictional model has been improved here because the driving force also includes the membrane-solute potential interaction, thus allowing the solute partition coefficient to appear in the calculations naturally. By recognizing that because of the membrane-solution interaction, external forces of both potential and frictional character are present, the dissipation function is shown to depend explicitly on the centre-of-mass velocity. Thus the reference velocity for diffusive fluxes cannot be chosen arbitrarily, making Prigogine's theorem invalid in this approach to describing membrane permeation.
5 citations
TL;DR: In this paper, the excess Gibbs energy values for selected vapor-liquid equilibrium systems modelled by the gamma/phi formulation were calculated from the conventional equation which is based on Raoult's law being the reference system and from equations for which the standard states correspond to the actual states of the pure components.
2 citations
1 citations
01 Jan 1989
TL;DR: In this article, the authors examine possible interpretations of Gibbs phase rules for equilibrium in fluid systems of several phases in which surface energies are a dominant component of the relevant free energy, and briefly discuss more elaborate situations.
Abstract: The pioneering work of Ennio De Giorgi and Herbert Federer in the 1950’s on the structure of sets of finite perimeter laid a mathematical foundation for much of modern geometric measure theory. This contribution to continuum thermodynamics is formulated in this tradition. We here wish to examine possible interpretations of Gibbs’s phase rules for equilibrium in fluid systems of several phases in which surface energies are a dominant component of the relevant free energy. We initially consider a simple model problem in some detail and then briefly discuss more elaborate situations.