Search results for "Numeral system"
showing 10 items of 124 documents
Densities, refractive indices, and derived excess properties of tert-butyl alcohol, methyl tert-butyl ether and 2-methylpentane binary and ternary sy…
2000
Abstract This paper reports experimental densities and refractive indices of the binary systems tert-butyl alcohol (TBA)+methyl tert-butyl ether (MTBE), TBA+2-methylpentane, and MTBE+2-methylpentane, and the ternary system TBA+MTBE+2-methylpentane, over the entire range of composition at 303.15 K. Excess molar volumes and changes of refractive indices were evaluated from the experimental data obtained. These derived properties were fitted to variable-degree polynomials. The experimental values of physical properties were compared with the values estimated by different methods of prediction.
Densities, refractive indices, and derived excess properties of the binary systems tert-butyl alcohol+toluene, +methylcyclohexane, and +isooctane and…
1999
Abstract This paper reports experimental densities and refractive indices of the binary systems tert -butyl alcohol (TBA)+toluene, +isooctane, and +methylcyclohexane, and toluene+methylcyclohexane, and the ternary system TBA+toluene+methylcyclohexane, over the entire range of composition at 298.15 K. Excess molar volumes and changes of refractive indices were evaluated from the experimental data obtained. These derived properties were fitted to variable-degree polynomials. The experimental values of physical properties were compared with the values estimated by different methods of prediction.
NUMERAL CONSTRUCTIONS IN SPOKEN ITALIAN AND SPANISH: FROM QUANTITATIVE APPROXIMATION TO INTERPERSONAL RELATIONSHIPS
2019
Two general considerations can derived from all the considered data. Firstly, it is possible to trace a continuum of NuCxs based on their degree of cohesion, fixedness, specificity and idiomaticity, which correlates with the kind of approximate or vague meaning and function. The more the NuCxs become idiomatic the less they express quantity. In many cases, the constructions acquire a pragmatic value and codify a manner of express the degree of commitment, the attitude of the speakers and the kind of relationship s/he would like to enter into with the addressee. In these cases, the various levels of vagueness are often thickly intertwined and not easily untangled. Secondly, the approximate n…
Study of liquid–liquid equilibria at different temperatures of water + ethanol + 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide tern…
2016
Abstract The experimental liquid–liquid equilibria (LLE) data of the water + ethanol + 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([bmp][Tf2N]) system has been measured at different temperatures in this work. The LLE of the system has been measured at between 283 and 333 K. The UNIQUAC and NRTL models were used to correlate the LLE data and good results were obtained in both cases, however UNIQUAC gave a more accurate correlation. In order to apply the UNIQUAC model the volume and surface parameters for [bmp][Tf2N] (r, q) were determined. Finally, in order to obtain ethanol from the aqueous mixture, the solvent capability of the ionic liquid was checked and compared wit…
Isobaric Vapor−Liquid Equilibrium in the Systems Methyl 1,1-Dimethylethyl Ether + 2-Methyl-2-propanol and Methyl 1,1-Dimethylethyl Ether + 2-Methylpe…
1999
Consistent vapor−liquid equilibrium data for the binary and ternary systems methyl 1,1-dimethylethyl ether (MTBE) + 2-methyl-2-propanol (TBA) and methyl 1,1-dimethylethyl ether (MTBE) + 2-methylpentane + 2-methyl-2-propanol (TBA) are reported at 101.3 kPa at temperatures in the range 328 to 356 K. The results indicate that the systems deviate positively from ideality and that no azeotrope is present. The activity coefficients of the solutions were correlated with composition by Wilson, NRTL, and UNIQUAC models. It is shown that the models allow a very good prediction of the phase equilibrium of the ternary system using the pertinent parameters of the binary system. In addition, the Wisniak−…
Isobaric (vapour+liquid+liquid) equilibrium data for (di-n-propyl ether+n-propyl alcohol+water) and (diisopropyl ether+isopropyl alcohol+water) syste…
2008
Abstract Isobaric (vapour + liquid + liquid) equilibria were measured for the (di-n-propyl ether + n-propyl alcohol + water) and (diisopropyl ether + isopropyl alcohol + water) system at 100 kPa. The apparatus used for the determination of (vapour + liquid + liquid) equilibrium data was an all-glass dynamic recirculating still with an ultrasonic homogenizer couple to the boiling flask. The experimental data demonstrated the existence of a heterogeneous ternary azeotrope for both ternary systems. The (vapour + liquid + liquid) equilibria data were found to be thermodynamically consistent for both systems. The experimental data were compared with the estimation using UNIQUAC and NRTL models a…
Isobaric vapor–liquid equilibrium for binary and ternary mixtures of 2-methyl-2-propanol+methyl 1,1-dimethylpropyl ether+2,2,4-trimethylpentane
2000
Abstract New consistent vapor–liquid equilibrium (VLE) data for the binary system methyl 1,1-dimethylpropyl ether (TAME)+2,2,4-trimethylpentane (isooctane) and the ternary system 2-methyl-2-propanol (TBA)+methyl 1,1-dimethylpropyl ether (TAME)+2,2,4-trimethylpentane (isooctane) are reported at 101.3 kPa. In the binary system, the results indicate a positive deviation from ideality and no azeotrope is present. The ternary system presents a saddle point azeotrope that can be predicted from binary data. The activity coefficients and boiling points of the solutions were correlated with their composition by Wilson, UNIQUAC and NRTL equations.
Liquid–Liquid Equilibria of the Water + 1-Propanol + 1-Butyl-1-methylpyrrolidinium Bis(trifluoromethylsulfonyl)imide Ternary System: Study of the Abi…
2016
An important problem in the chemical industry is the separation of azeotropes. Their separation by simple distillation is basically impossible, and extractive distillation consumes much more energy than liquid–liquid extraction, so this alternative could be interesting. Recently, researchers have started to explore these option using ionic liquids as the solvent. The remarkable properties of ionic liquids have made them sustainable alternatives to conventional solvents. This work is a continuation of a study developed by our research group on the use of ionic liquids as extractant solvents of alcohol + water mixtures which form azeotropes, using in this case 1-butyl-1-methylpyrrolidinium bi…
Liquid–Liquid Equilibria of Water + Ethanol + 1-Butyl-3-methylimidazolium Bis(trifluoromethanesulfonyl)imide Ternary System: Measurements and Correla…
2015
In this work authors present the experimental liquid–liquid equilibria (LLE) data of water + ethanol + 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide ([bmim][Tf2N]) system at different temperatures. The LLE of the system was obtained in the temperature range from 283.2 to 323.2 K. The nonrandom two liquid (NRTL) and universal quasichemical (UNIQUAC) models were used to correlate ternary systems. The equilibrium compositions were successfully correlated by the interaction parameters from both models, however UNIQUAC gave a more accurate correlation. Finally, a study about the solvent capability of ionic liquid was made in order to evaluate the possibility of separating the mi…
Isobaric vapor–liquid equilibria for binary and ternary mixtures with cyclohexane, cyclohexene, and morpholine at 100kPa
2010
Abstract Vapor–liquid equilibria (VLE) data at 100 kPa have been determinated for the ternary system cyclohexane + cyclohexene + morpholine and two constituent binary systems cyclohexane + morpholine and cyclohexene + morpholine. The thermodynamic consistency of experimental data has been verified. Both binary systems deviate moderately from ideality without the presence of an azeotrope. The VLE data have been well correlated using local composition models (Wilson, NRTL and UNIQUAC) and have been also predicted with the original UNIFAC.