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Showing 1 to 10 of 10 for “"excess Gibbs energy"”.
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Entwicklung der Gruppenbeitragsmethode GEQUAC zur thermodynamischen Beschreibung ausgeprägt nichtidealer Gemische
In this study the physically founded excess Gibbs-energy model GEQUAC for the description of strongly non-ideal mixtures is analyzed and further developed. According to the model concept the interactions in the liquid mixture take place between different poles on the molecular surface. The …
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Korrosion von polykristallinem Aluminiumoxid (PCA) durch Metalljodidschmelzen sowie deren Benetzungseigenschaften
On high-energy discharge lamps with burners consisting of polycrystalline aluminum oxide (PCA) corrosion leads to relocation of the wall material; the extent of the phenomenon depends on the composition and the wetting behaviour of the liquid salt mixture contained in the lamp. The aim of this work …
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Limiting Activity Coefficients for Aqueous Solutions
… demonstrate the limitations of several current excess Gibbs energy expressions in representing both vapor-liquid and liquid-liquid equilibrium data from $\gamma\sp\infty$ measurements. A new technique for measuring limiting activity coefficients of low relative volatility solutes was developed …
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Properties Model for Aqueous Sodium Chloride Solutions near the Critical Point of Water
Traditional excess Gibbs energy models in terms of temperature, pressure, and concentration become progressively less effective in describing the thermodynamics of aqueous solutions at temperatures above 300 ¢ªC, and are totally inadequate in the critical region of water. This deficiency is due …
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Models of gas-liquid solubilities
… been used to predict activity coefficients and excess Gibbs energy for binary mixtures with good accuracy. The theory, based on a generalised London potential (GLP), accounts for intermolecular attractive forces. Unlike existing prediction methods, for example UNIFAC, the AGAPE method uses only …
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An Improved Model for Calculating Heats of Dilution and Equilibrium Constants for High Temperature Aqueous Electrolyte Solutions
… have designed a correlation model based on the excess Gibbs energy which can correlate log K and ∆H values as well as the heats of dilution for aqueous electrolyte systems as a function of temperature (T) and ionic strength (I) from 275 to 350°C. Use of calorimetric data to develop the model has …
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Measurement, prediction, and application of the limiting activity coefficient and its temperature derivative
… to give an estimate of the partial molar excess enthalpy at infinite dilution (h$\sp{\rm E\infty}$). An asymmetric isothermal flow calorimeter was developed to obtain excess enthalpies (h$\sp{\rm E}$) of binary liquid mixtures of nonelectrolytes in the dilute region, and these values were …
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Crystallization of calcium sulphate during phosphoric acid production : improving filtration through improvement in particle shape and size distribution
… solid-liquid equilibrium by calculating excess Gibbs energy from additive pairwise interactions. When impurities are present, additional binary interactions need to be included in the databank, which is carried out by regression analysis using solubility measurements. Continuous reactive …
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Computational Modeling of Osmotically Assisted Membrane Separations with Multicomponent Solution-diffusion Theory
… high concentrations, or in mixtures with large excess Gibbs energy of mixing. In this study, we develop a new multicomponent solution-diffusion model by combining the frameworks of multicomponent Fickian diffusion and solution-diffusion theory. The derived model introduces multicomponent …
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MOQUAC, a new expression for the excess Gibbs free energy based on molecular orientations
… a model to predictively describe the interaction energy between real molecules as a function of their orientation is derived. It is shown that MOQUAC can be used together with this interaction-energy model to predict the behavior of systems of real components. In addition to a new expression for …