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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 +12 more
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A Helmholtz free-energy function for a Cu–Al–Ni shape memory alloy
International Journal of Non-Linear Mechanics, 2005Abstract In this paper we develop a free energy function for a Cu–Al–Ni alloy undergoing cubic–orthorhombic phase transitions. We use the irreducible Lagrangian strain polynomial invariants of the cubic austenite parent phase to construct a polynomial expansion for the Helmholtz free energy.
Vedantam, S., Abeyaratne, R.
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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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Helmholtz Free-Energy Bounds from High-Temperature Series?
The Journal of Chemical Physics, 1970In theoretical equation-of-state investigations an important goal is to obtain the Helmholtz free energy, from which other thennod)lnamic properties can be obtained. The Helmholtz free energy is hard to cal culate directly. A less ambitious goal is to relate the free energy for the system of interest to the properties of a simpler, well-understood ...
W. T. Ashurst, W. G. Hoover
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Helmholtz free energy for two-dimensional Lennard-Jones fluids
Chemical Physics, 1993Abstract The Helmholtz free energy for two-dimensional Lennard-Jones fluids is calculated over a wide range of densities and temperatures from computer simulation results for the radial distribution function. The applicability to this calculation of the first-order Weeks-Chandler-Andersen theory, called the high-temperature approximation, is verified.
F. Cuadros, A. Mulero
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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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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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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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