Surface tension measurements were performed by the Wilhelmy plate method. Measured systems included pure heptane, decane, hexadecane, eicosane, and some of their binary mixtures at temperatures from 293.15 K to 343.15 K with an average absolute deviation of 1.6%. The results were compared with a new corresponding states model. The average absolute deviation was found to be 1.0%.

The solubilities of tetracycline hydrochloride, moxifloxacin hydrochloride, and ciprofloxacin hydrochloride were measured in several solvents, such as water, ethanol, 2-propanol, and acetone, in the temperature range of 293.15-323.15 K for ciprofloxacin.HCl and moxifloxacin.HCl and 288.15-310.15 K for tetracycline. All the antibiotics have the same solubility order; that is, they are more soluble in water than in ethanol, and more soluble in ethanol than in 2-propanol and acetone. The solubility in water is ∼3 orders of magnitude higher than that in acetone. The modeling of the experimental solid-liquid equilibria (SLE) data, using the NRTL and UNIQUAC models, proves that these models can correlate the solubility of studied antibiotics satisfactorily in the temperature range for which experimental data are available, with the UNIQUAC model generally being slightly superior to the NRTL model, when only two adjustable parameters are used for each binary system.

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Vapor pressures and liquid densities of highly fluorinated compounds were measured in this work. Vapor pressures were measured in the temperature range between 288 K and 333 K with an apparatus based on the static method. Liquid densities were measured with a vibrating tube densimeter in the temperature range between 288 K and 313 K. Experimental data was fitted with appropriate equations and compared with literature data when possible. Vapor pressures and densities were also correlated with the soft-SAFT equation of state, and the fitted parameters for the studied fluids are presented. The boiling points, enthalpies of vaporization, and thermal expansion coefficients, derived from vapor pressure and density data, are also reported.

A tensiometer operating on the Wilhelmy plate method was employed to measure liquid-vapor interfacial tensions of three binary mixtures and one ternary mixture of decane with eicosane, docosane, and tetracosane. Tensions of binary mixtures n-

The aim of this work is to establish a comparison between the solubility of the hydrochloride and nonhydrochloride forms of ciprofloxacin and tetracycline in relevant solvents. For that purpose the solubilities of the non-hydrochloride forms of ciprofloxacin and tetracycline were measured in water, ethanol, 2-propanol, and acetone, in the temperature range between 293.15 and 323.15 K for ciprofloxacin and between 288.15 and 303.15 K for tetracycline. The obtained results were compared with those of part I of this study, published previously, where the solubilities of the respective hydrochloride forms of the antibiotics in the same solvents were investigated. The solubility of the hydrochloride forms in water is about 2 orders of magnitude higher than those of the respective base forms. In acetone, we see the opposite effect. For ethanol and 2-propanol the influence of the hydrochloride group of the antibiotic on the solubility in the alcohol is much smaller than for water and acetone. The experimental data was correlated with good results using two different activity coefficient models, NRTL and UNIQUAC, with UNIQUAC giving better results, particularly for ciprofloxacin. The performance of COSMO-RS model to describe the studied systems was also evaluated.

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