Biomedical subjects

Grit Kalies

Publications and source records attributed to Grit Kalies.

5 recordsLinked to original sources

PubMed2006

Simultaneous adsorption at the liquid/solid and liquid/gas interfaces.

Physical adsorption from binary or higher-order liquid mixtures on solids is often accompanied by adsorption phenomena at the liquid/gas interface. As long as the adsorption effects are comparable, both interfaces have to be included in the respective thermodynamic equations. A purely phenomenological thermodynamic description in terms of excess quantities is given of the simultaneous adsorption from multicomponent liquid mixtures at the liquid/solid and liquid/gas interfaces. In order to illustrate the thermodynamic procedure, the individual and simultaneous adsorption excess isotherms of three binary liquid mixtures at the liquid/Teflon and liquid/vapor interfaces are calculated from experimental surface-tension and contact-angle data taken from the literature. Special attention is focused on the estimation of error in calculated adsorption isotherms. A line of approach is given to find the confidence limits of adsorption isotherms that cover the entire mole fraction scale. The isotherms as well as their confidence limits are presented and discussed.

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PubMed2005

Calculation of immersion enthalpy data from adsorption isotherms.

The thermodynamic equations for the calculation of binary and ternary immersion data in excess formalism are presented. Immersion enthalpies and entropies of the n-hexane/n-octane, n-octane/n-tetradecane and n-hexane/n-tetradecane binary mixtures as well as the n-hexane/n-octane/n-tetradecane ternary mixture on activated carbon are calculated from the temperature dependence of adsorption isotherms. In order to evaluate the quality of the calculations, the calculated immersion enthalpies of the binary mixtures on activated carbon are compared with those that were measured calorimetrically. It is shown that phenomenological thermodynamics can be used successfully to predict calorimetric data on the basis of adsorption excess isotherms.

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PubMed2004

Prediction of multicomponent liquid adsorption using excess quantities. II. Calculations for the liquid/solid interface.

The utilization of excess quantities as the basis for a thermodynamic approach can simplify the prediction of multicomponent liquid adsorption from binary data. A new method for predicting liquid adsorption on solids is suggested, which is different from the existing equations with respect to the theoretical background and formulation. The applicability of the new model is tested with three ternary adsorption systems. The predicted surface excesses are discussed and compared with experimental ones and with those of other prediction models in the literature. The accordance between measured and predicted ternary data is convincing.

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PubMed2004

Prediction of multicomponent liquid adsorption using excess quantities I. Statistical thermodynamic derivation of the basic equation of excess formalism.

The utilization of excess quantities as the basis of a thermodynamic approach can simplify the prediction of multicomponent liquid adsorption from binary data. From statistical thermodynamics, the fundamental equation is derived for the prediction of ternary or higher order data from adsorption data for the constituent binary mixtures. An additive expression is obtained for the double Gibbs free excess energies, valid for adsorption on liquid mixture/air interfaces as well as liquid mixture/solid interfaces.

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PubMed2002

Calculation and prediction of adsorption excesses on the ternary liquid mixture/air interface from surface tension measurements.

The surface tensions of the n-propanol/ethylene glycol/water ternary mixture and its binary mixtures are measured at 293 K and described by mathematical functions. The experimental data and their descriptions are shown in the three-dimensional space by means of coordinate transformation. A thermodynamic model to calculate and predict ternary adsorption excess data on the ternary liquid mixture/air interface from surface tensions is presented. The calculated adsorption excess data in the ternary triangle are discussed.

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