Showing papers on "Gibbs–Helmholtz equation published in 1978"
TL;DR: In this paper, the Gibbs equation for stressed solids is extended to include constrained chemical equilibria among components whose chemical potentials may not be individually definable, and a programmed dif-fusion scheme is devised to minimize both the diffusion time and the stress developed dur-ing diffusion.
Abstract: Gibbs equation for stressed solids is extended to include constrained chemical equilibria among components whose chemical potentials may not be individually definable. Strain volume is introduced as a new tensorial extensive variable. Solubility enhancements in the presence of misfit inclusions of spherical as well as parallelepipedal shapes are cal-culated an compared with experiments involving excess nitrogen around TiN2 platelet inclusions in ferrite. Diffusion-induced stresses or the chemical stress effect is treated for some simple shapes such as thin slabs, cylinders, and spheres. A programmed dif-fusion scheme is devised to minimize both the diffusion time and the stress developed dur-ing diffusion. The effective diffusivity of an isotropic solute due to diffusion-induced stress gradients is given. Stress induced diffusion is exemplified by a new creep test in which diffusion is localized around an indenter. Finally, the chemical kinetics of the annealing of defects are discussed with new experiments reported on the recovery kinetics of shearbands produced in an amorphous polymer.
187 citations
17 citations
TL;DR: In this article, an approach for the substantiation of the Gibbs method in equilibrium statistical thermodynamics is described; this approach is based not on the quasiergodicity hypothesis, but on the weaker assumption of macroscopic determinacy of thermodynamic systems.
Abstract: An approach for the substantiation of the Gibbs method in equilibrium statistical thermodynamics is described; this approach is based not on the quasiergodicity hypothesis, but on the weaker assumption of macroscopic determinacy of thermodynamic systems. A generalized microcanonical Gibbs distribution is obtained. An electron gas in a homogeneous magnetic field is taken as an example. It is shown that the classical diamagnetism of the given system is not zero in the sense of quasimean nor of generalized Gibbs ensemble distributions. The equation of state of an electron as in a magnetic field is obtained, and hence it is shown that classical diamagnetism only vanishes if isotropy of the pressure at the vessel wall is assumed.
TL;DR: The specific heat, entropy, enthalpy, and Gibbs free energy of methyl thiolformate and methylchloroformate have been calculated at selected temperatures using fundamental frequencies of vibration and structural parameters.
Abstract: The specific heat, entropy, enthalpy, and Gibbs free energy of methyl thiolformate and methylchloroformate have been calculated at selected temperatures using fundamental frequencies of vibration and structural parameters.