Comment on ‘On the importance of the free energy for elasticity under pressure’
نویسندگان
چکیده
Marcus et al. (Marcus P, Ma H and Qiu S L 2002 J. Phys.: Condens. Matter 14 L525) claim that thermodynamic properties of materials under pressure must be computed using the Gibbs free energy G, rather than the internal energy E. Marcus et al. state that “The minima of G, but not of E, give the equilibrium structure; the second derivatives of G, but not of E, with respect to strains at the equilibrium structure give the equilibrium elastic constants.” Both statements are incorrect. Submitted to: J. Phys.: Condens. Matter
منابع مشابه
Small Scale Effect on the Buckling Analysis of a Double-Walled Carbon Nanotube under External Radial Pressure Using Energy Method
In this paper, using energy method, small scale effects on the buckling analysis of a double-walled carbon nanotube (DWCNT) under external radial pressure is studied. The constitutive equations derived for a DWCNT using the nonlocal theory of elasticity which Eringen are presented for the first time. By minimizing the second variation of the total energy for a DWCNT, hence, the value of the non...
متن کاملEffect of Secondary Task on the Basketball Free Throw Accuracy on Choking under Pressure Skilled players
The aim of this study was to determine the effect of secondary task relevant and non-relevant to the free throw basketball skill on the free throw accuracy of basketball skilled players in choking under pressure. Twenty right-handed female players (aged 18-30) each with at least three years of experience in basketball took part study after completing the Sport Competition Anxiety Test (SCAT), A...
متن کاملLongitudinal Magnetic Field Effect on Torsional Vibration of Carbon Nanotubes
Torsional dynamic analysis of carbon nanotubes under the effect of longitudinal magnetic field is carried out in the present study. Torque effect of an axial magnetic field on a carbon nanotube has been defined using Maxwell’s relation. Nonlocal governing equation and boundary conditions for carbon nanotubes are obtained by using Hamilton’s minimum energy principle. Eringen’s nonlocal stress gr...
متن کاملSmall Scale Effect on the Vibration of Orthotropic Plates Embedded in an Elastic Medium and Under Biaxial In-plane Pre-load Via Nonlocal Elasticity Theory
In this study, the free vibration behavior of orthotropic rectangular graphene sheet embedded in an elastic medium under biaxial pre-load is studied. Using the nonlocal elasticity theory, the governing equation is derived for single-layered graphene sheets (SLGS). Differential quadrature method (DQM) has been used to solve the governing equations for various boundary conditions. To verify the a...
متن کاملForced vibration of piezoelectric nanowires based on nonlocal elasticity theory
In this paper, a numerical solution procedure is presented for the free and forced vibration of a piezoelectric nanowire under thermo-electro-mechanical loads based on the nonlocal elasticity theory within the framework of Timoshenko beam theory. The influences of surface piezoelectricity, surface elasticity and residual surface stress are taken into consideration. Using Hamilton’s principle, t...
متن کامل