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A Helmholtz Free Energy Formulation of the Thermodynamic Properties of the Mixture {Water + Ammonia}
Journal of Physical and Chemical Reference Data, 1998A thermodynamic model incorporating a fundamental equation of state for the Helmholtz free energy of the mixture {water+ammonia} is presented which covers the thermodynamic space between the solid–liquid–vapor boundary and the critical locus. It is also valid in the vapor and liquid phases for pressures up to 40 MPa.
Reiner Tillner-Roth, Daniel G. Friend
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Helmholtz free energy equation of state for propane and R134a binary mixture
International Journal of Refrigeration, 2018Abstract In this work, a Helmholtz free energy equation of state for R290 + R134a based on the multi-fluid approximations model was developed to describe the thermophysical properties of the binary mixture. The present equation shows more competitive than the default equation in REFPROP 9.1 (Lemmon et al., 2013). It covers a temperature range of (252–
Haiyang Zhang, Bo Gao, Wei Wu
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Helmholtz free energy of finite spin systems near criticality
Physical Review B, 1987We present a quantitative comparison between 4 − e expansion and Monte Carlo estimates of critical finite-size properties: Specifically we consider the Helmholtz free energy (where the overall order parameter rather than its conjugate field is kept fixed) at the bulk critical temperature for a cube with periodic boundary conditions within a 4 − e ...
, Eisenriegler, , Tomaschitz
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A characterization of the Helmholtz free energy
Journal of Mathematical Physics, 2013Let \documentclass[12pt]{minimal}\begin{document}$\mathcal {{{H}}}$\end{document}H be a finite dimensional complex Hilbert space, \documentclass[12pt]{minimal}\begin{document}${\mathbb {B}}(\mathcal {{{H}}})_{+}$\end{document}B(H)+ be the set of all positive semi-definite operators (matrices) on \documentclass[12pt]{minimal}\begin{document}$\mathcal {{{
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Upper bounds on the helmholtz free energy
Chemical Physics Letters, 1970Abstract Expressions are derived that bound from above the Helmholtz free energy of a classical system.
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Gibbs and Helmholtz Free Energies
2020Two state functions have been formulated based on the spontaneity criterion for a given process, i.e. the positive entropy production: Gibbs free energy (for constant pressure and constant temperature conditions) and Helmholtz free energy (for constant volume and constant temperature conditions).
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Calculation of the Helmholtz free energy with approximate Green's functions
Physica A: Statistical Mechanics and its Applications, 1994Abstract We employ approximate Green's Functions (GF) to obtain the Helmholtz free energy F in a Grand Canonical Ensemble. This study was motivated by the calculation of the total number of electrons N t as a function of the chemical potential μ in the Periodic Anderson Model by employing approximate one-electron GF.
M.S. Figueira, M.E. Foglio
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A corresponding-states Helmholtz-free-energy model based on a conformality analysis
High Temperatures-High Pressures, 2000In recent times, for fluids belonging to the alkane and halogenated-alkane families, several high accuracy dedicated equations of state (DEOS) have been published and models based on the corresponding-states (CS) format have often been utilised to calculate thermodynamic properties.
G. Cristofoli +2 more
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Two-phase flash for tight porous media by minimization of the Helmholtz free energy
Fluid Phase Equilibria, 2020Abstract Thermodynamic modeling of phase behavior is one of the most fundamental components in the study of enhanced oil recovery by gas injection. Robust algorithms exist for multiphase equilibrium problems with no capillary pressure as commonly used in compositional reservoir simulation.
Sofiane Haythem Achour, Ryosuke Okuno
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