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Abstract: Experimental solubilities of betulin in mixed solvents of chloroform (1)+methanol (2) were determined at T =(278.2, 288.2, 293.2, 298.2, 308.2 and 313.2) K. The solubilities of betulin in mixed solvents of chloroform (1)+methanol (2) increase with increasing of temperature. The curves of solubility versus solvent composition on solute-free basis went through a maximum. Experimental data of solubilities were correlated with a three-parameter equation. In addition, three crystals of betulin obtained in different compositions of chloroform (1)+methanol (2) mixtures were characterized by scanning electron microscope (SEM) and differential scanning calorimetry (DSC). [Copyright &y& Elsevier]

Abstract: Molar excess enthalpies of ethanol, 1-propanol, 2-propanol and 1-butanol+1-butyl-3-methyl-imidazolium hexafluorophosphate, [bmim]PF6 at highly diluted region of organic solvents were determined using isothermal titration calorimeter (ITC) at 288.15, 298.15, 308.15 and 318.15K. The experimental data were fitted with a Redlich–Kister equation. The partial molar excess enthalpies at infinite dilution, were calculated using the parameters of the Redlich–Kister equation. [Copyright &y& Elsevier]

Abstract: The excess molar enthalpies of four binary systems for ethyl acetoacetate+(methanol, +ethanol, +1-propanol, and +2-propanol) at T =(298.15, 313.15, and 328.15)K and p =(0.1 and 10.0)MPa were determined by a high pressure flow-mixing isothermal microcalorimeter. The densities of ethyl acetoacetate at T =(278.15, 288.15, 298.15, 313.15, 328.15, 338.15, and 348.15)K were determined by pycnometer. The excess molar enthalpies increase with an increase in the temperature and the molecular size of alcohols and decrease with an increase in pressure. The experimental data were correlated by the Redlich–Kister equation and two local composition models (NRTL and UNIQUAC). [Copyright &y& Elsevier]