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Intradiffusion coefficients of acetylacetone(AcAc) and DMF/DMSO/benzene in binary systems over the entire concentration range at 303.15 K were determined by 1H diffusion-order spectroscopy(DOSY) nuclear magnetic resonance(NMR) method based pulse field gradient(PFG).The densities and viscosities of the above three binary systems at 303.15 K were also studied and employed to calculate the excess molar volumes(V~E) and deviations in viscosity(△η).Besides,experiments were carried out at 333.15 K for the system of AcAc+DMF.The solvent and temperature effect upon the difference in D between enol and keto tautomers,the tautomeric equilibrium and excess properties(V~E and △η) were discussed as well.Isotherms of V~E as a function of mole fraction of AcAc(χ_1) show positive deviations in benzene but negative deviations in DMF and DMSO,whereas isotherms of △ηas a function of χ_1 record positive deviations in DMF but negative in benzene and DMSO.V~E values show more negative and △η values are less positive in the system of AcAc+DMF at 333.15 K compared to 303.15 K.The V~E and △η were fitted to a Redlich-Kister type equation and the measured results were interpreted concerning molecular interactions in the solutions.
Intradiffusion coefficients of acetylacetone (AcAc) and DMF / DMSO / benzene in binary systems over the entire concentration range at 303.15 K were determined by 1H diffusion-order spectroscopy (DOSY) nuclear magnetic resonance (NMR) method based pulse field gradient (PFG). The densities and viscosities of the above three binary systems at 303.15 K were also studied and employed to calculate the excess molar volumes (V~E) and deviations in viscosity (Δη) .Besides, experiments were carried out at 333.15 K for the system of AcAc + DMF. The solvent and temperature effect upon the difference in D between enol and keto tautomers, the tautomeric equilibrium and excess properties (V~E and Δη) were discussed as well. Isotherms of V ~ E as a function of mole fraction of AcAc (x 1) show positive deviations in benzene but negative deviations in DMF and DMSO, while isotherms of Δ η a a function of χ 1 record positive deviations in DMF but negative in benzene and DMSO.V~E values show more negative and Δ η v alues are less positive in the system of AcAc + DMF at 333.15 K vs. 303.15 K. The V ~ E and Δη were fitted to a Redlich-Kister type equation and the measured results were distinguished concerning molecular interactions in the solutions.