کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
674112 | 1459540 | 2012 | 4 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Influence of the composition of aqueous-alcohol solvents on thermodynamic characteristics of dl-α-alanyl-dl-norleucine dissolution at 298.15 K Influence of the composition of aqueous-alcohol solvents on thermodynamic characteristics of dl-α-alanyl-dl-norleucine dissolution at 298.15 K](/preview/png/674112.png)
Dissolution enthalpies (ΔsolHm) of dl-α-alanyl-dl-norleucine in binary mixtures containing water + (EtOH, 1-PrOH and 2-PrOH at 0–0.4 mole fraction) at 298.15 K and atmospheric pressure have been determined as a function of the composition using an isothermic calorimeter. The results obtained have been used to calculate standard enthalpies of a solution (ΔsolH°) and transfer (ΔtrH) of dl-α-alanyl-dl-norleucine from water into the mixtures as well as enthalpy coefficients of pairwise interaction (hxy) of the solute with alcohols in aqueous media. The ΔtrH° values are positive for all mixtures over the whole composition range. The influence of the co-solvent structure and of the content of mixtures and of a side-chain of peptide on the change of ΔtrH° (hxy) is discussed.
► Enthalpies of dl-α-alanyl-dl-norleucine dissolution have been measured in aqueous solution of EtOH, 1-PrOH and 2-PrOH.
► Measured data were reported as functions of composition of water + alcohol mixtures.
► Enthalpy coefficients of pairwise interactions have been analyzed in terms of McMillan–Mayer theory.
Journal: Thermochimica Acta - Volume 544, 20 September 2012, Pages 43–46