Volumetric and viscometric properties of amino acids in aqueous maltitol solutions at T = (293.15-323.15) K

摘要

The densities and viscosities of the ternary mixtures of glycine, L-alanine, L-valine, L-threonine and L-arginine in aqueous maltitol solutions were measured at T = (293.15-323.15) K under the atmospheric pressure. The apparent molar volume (V-phi), the limiting partial molar volume (V-phi(0)) and the limiting partial molar volume of transfer (Delta V-tr(phi)0) were obtained in terms of the measured density, then the viscosity B-coefficient was further calculated by the least-square method. Meanwhile, the partial molar isobaric expansion (E-2(0)), the isobaric thermal expansion coefficient (alpha(2)), the solvation number (n(S)), the free energies of activation per mole of solvent (Delta mu(0-)(1)) and per mole of solute (Delta mu(0-)(2)) were also calculated. The volumetric and viscometric properties were analyzed and discussed according to the interactions between amino acids and maltitol molecules based on the co-sphere overlap model and the transition state theory. (C) 2017 Elsevier Ltd.