J. Valero

Vapour pressures of (butan-1-ol + hexane) at temperatures between 283.10 K and 323.12 K

Vapour pressures by a static method of n -hexane, n -butan-1-ol, and ( n -butan-1-ol + n -hexane) at temperatures between 283.10 K and 323.12 K at about 5 K intervals, were measured. Activity coefficients and excess molar Gibbs free energies G E m were calculated by Barkers method. Three different types of equations for G E m were used for fitting the experimental results. For alcohol-dilute mixtures, formation of an azeotropic mixture with a minimum boiling temperature was observed.

HmE and VmE of some (butanone or dipropylether + an alkanol) mixtures

Abstract Molar excess enthalpies and volumes of (butanone or dipropylether + alkanol) at 298.15 K (in some cases at 308.15 K, too) were measured. The different behaviour observed in each non-alkanol component is put down for the most part to an unlike dipolar contribution. Mixtures containing 2-methylpropan-2-ol deviate from the systematic behaviour of those with n -alkan-1-ols.

Excess enthalpies of some (chloroalkane + n-alkane) mixtures

Abstract Excess enthalpies at 298.15 K of some (chloroalkane + n-alkane) mixtures are reported. Excess enthalpies at x = 0.5 for 1-chlorobutane + and t-butylchloride + an n-alkane are compared with those of n-hexane+ and 2,2-dimethylbutane + the same n-alkane. In both sets the differences between the excess enthalpies observed for the branched compound and for the normal one are similar.

HmE of (an n-alkane + a butanol isomer)

Abstract Excess molar enthalpies of (an n -alkane + a butanol isomer) were measured at 298.15 and 318.15 K. The peculiar shapes of the curves, especially for mixtures containing 2-methylpropan-2-ol, might be put down to the formation of cyclic multimers. The temperature coefficients of H m E are always positive and they increase as the chain-length of the n -alkane increases.

Vapour pressures of {xC4H9OH + (1−x)C8H18}(l) at temperatures between 283.16 K and 323.18 K

Vapour pressures of octane and of (butan-1-ol + octane), at about 5 K intervals between the temperatures 283.16 K and 323.18 K, were measured by a precise static method. Following Barkers method, the activity coefficients and the excess molar Gibbs energies were fitted to a polynomial of degree three. Azeotropic mixtures with a minimum boiling temperature, richer in butan-1-ol with increasing temperature, were observed over the whole temperature range.

Excess molar volumes of several mixtures containing 1,2-dichloroethane

Abstract Excess molar volumes of n -hexane +, 2,2-dimethylbutane +, cyclohexane +, n -hexadecane +, benzene +, and tetrachloromethane + 1,2-dichloroethane, at four temperatures ranging from 288.15 to 318.15 K (298.15 to 328.15 K in the case of n -hexadecane + 1,2-dichloroethane) were measured. The positive temperature coefficients are explained in terms of the conformational equilibrium in 1,2-dichloroethane.

Excess enthalpies of mixtures containing salicylaldehyde or 2-methoxyethanol

Abstract Measurements of excess enthalpies at 298.15 K are reported for binary mixtures of salicylaldehyde or 2-methoxyethanol + cyclohexane, + benzene, and + tetrachloromethane. Some measurements have been carried out at 313.15 K. The different calorimetric behaviour of these mixtures is consistent with the occurrence of intramolecular hydrogen bonding in salicylaldehyde and intra- and inter-molecular hydrogen bonding in 2-methoxyethanol. An estimation of the intramolecular hydrogen-bond energy in 2-methoxyethanol is made.

Excess molar volumes of mixtures containing 1,2-dichloropropane or 1,3-dichloropropane

Excess molar volumes VmE of [(1−x)(n-C6H14 or n-C16H34 or CH3C(CH3)2CH2CH3 or c-C6H12 or CCl4 or C6H6) + x(CH2ClCHClCH3 or CH2ClCH2CH2Cl)] at 298.15 and 318.15 K were measured. Mixtures containing 1,2-dichloropropane show VmE values noticeably greater than those of mixtures with 1,3-dichloropropane, and they approach the theoretical Florys predictions.

Excess molar enthalpies of mixtures containing 1,3-dichloropropane

Abstract Excess molar enthalpies H m E of [(1− x ){C 6 H 14 or CH 3 C(CH 3 ) 2 CH 2 CH 3 or c -C 6 H 12 or CCl 4 or C 6 H 6 } + x CH 2 ClCH 2 CH 2 Cl] at four temperatures ranging from 288.15 to 318.15 K, and of {(1− x )C 16 H 34 + x CH 2 ClCH 2 CH 2 Cl} between 298.15 and 328.15 K, were measured. With alkanes, the curves of the excess molar heat capacity C p ,m E obtained from the H m E s show a double minimum.

Multiple interdigital neuromas: a retrospective study of 279 feet with 462 neuromas.

Mortons neuroma is a common pathologic entity that, traditionally, was considered to be an isolated tumor that rarely affected more than 1 interdigital space. However, in recent years, multiple neuromas have become more common in our day-to-day practice. The objective of the present study was to assess the frequency with which Mortons neuroma appears in the different interdigital spaces. A retrospective study was performed of 279 feet that had been surgically treated for Mortons neuroma using a dorsal approach during a 9-year period (from January 2003 to December 2011), with an ultrasound scan taken preoperatively and histopathologic analysis performed afterward. From the 279 treated feet, 462 interdigital neuromas were surgically removed. Of the 279 feet, 97 (34.8%) displayed isolated neuromas, and 182 (65.2%) were treated for multiple neuromas. Regarding the neuromas that were treated as isolated lesions, 74.2% were located in the third space. For the feet affected by multiple interdigital neuromas, 100% had a neuroma in the third space and 98.9% in the second. The incidence of multiple interdigital neuromas can be considered frequent. The assessment, therefore, of interdigital neuromas of the foot should include, at a minimum, the second and third interdigital spaces.