Search results for "Boiling"
showing 10 items of 50 documents
Effects of cooking on mollusk shell structure and chemistry: Implications for archeology and paleoenvironmental reconstruction
2016
Mollusk shells excavated from archeological sites have been used to reconstruct paleoenvironment, human foraging, and migratory patterns. To retrieve information on past environment or human behavior, chemical signatures such as oxygen stable isotopes (δ18Oshell) are analyzed. Shell archeological remains usually represent food waste. Thermal treatments such as boiling and roasting may influence shell structure and biochemical composition. However, little is known about the relationship between changes at macro-, microstructural and chemical levels. This work is a calibration study on modern Phorcus (Osilinus) turbinatus shells. A simulation of two different cooking methods (boiling and roas…
Isobaric vapour–liquid equilibria for the binary systems 4-methyl-2-pentanone+1-butanol and+2-butanol at 20 and 101.3kPa
2009
Abstract Isobaric vapour–liquid equilibrium (VLE) measurements for the binary systems 4-methyl-2-pentanone + 1-butanol and 4-methyl-2-pentanone + 2-butanol are reported at 20 and 101.3 kPa. The system 4-methyl-2-pentanone + 1-butanol presents a minimum boiling point azeotrope at both pressures (20 and 101.3 kPa) and the system 4-methyl-2-pentanone + 2-butanol presents only a minimum boiling azeotrope at 20 kPa. In both systems, which deviate positively from ideal behaviour, the azeotropic composition is strongly dependent on pressure. The activity coefficients and boiling points of the solutions were correlated with its composition by the Wilson, UNIQUAC, and NRTL models for which the param…
Isobaric Vapor−Liquid Equilibria of the Water + 1-Propanol System at 30, 60, and 100 kPa
1996
Isobaric vapor−liquid equilibria for the water + 1-propanol system are reported at 30, 60, and 100 kPa. The results were found to be thermodynamically consistent according to Van Ness−Byer−Gibbs, Kojima, and Wisniak methods. The system shows a minimum boiling azeotrope, and the azeotropic composition is scarcely shifted with pressure. Results were compared with literature values. The data were correlated with Margules, Van Laar, Wilson, NRTL, and UNIQUAC liquid-phase activity coefficient models.
Isobaric Vapor−Liquid Equilibria of the Water + 2-Propanol System at 30, 60, and 100 kPa
1996
Isobaric vapor−liquid equilibria were obtained for the water + 2-propanol system at 30, 60, and 100 kPa. The activity coefficients were found to be thermodynamically consistent by the methods of Van Ness−Byer−Gibbs, Kojima, and Wisniak. The data were correlated with five liquid phase activity coefficient models (Margules, Van Laar, Wilson, NRTL, and UNIQUAC).
Isobaric vapor–liquid equilibria for the binary systems 1-propyl alcohol+dipropyl ether and 1-butyl alcohol+dibutyl ether at 20 and 101.3kPa
2006
Abstract Isobaric vapor–liquid equilibrium measurements for the binary systems 1-propyl alcohol + dipropyl ether and 1-butyl alcohol + dibutyl ether are reported at 20 and 101.3 kPa. Both systems, which deviate positively from ideal behavior present a minimum boiling point azeotrope at both pressures, showing the azeotropic compositions a strong dependency on pressure. The activity coefficients and boiling points of the solutions were correlated with its composition by the Wilson, UNIQUAC, NRTL, and Wisniak–Tamir equations.
Isobaric vapor–liquid equilibrium for binary mixtures of 2-methylpentane+ethanol and +2-methyl-2-propanol
1999
Abstract Vapor–liquid equilibrium (VLE) data for the binary systems, 2-methylpentane+ethanol and 2-methylpentane+2-methyl-2-propanol (TBA), are reported at 101.3 kPa, including pure component vapor pressures. The systems deviate remarkably from ideal behaviour presenting one positive azeotrope. The activity coefficients and boiling points of the solutions were correlated with its composition by Wilson, UNIQUAC, NRTL, and Wisniak–Tamir equations.
Isobaric vapor-liquid equilibria and densities for the system methyl 1,1-dimethylethyl ether+2-propanol
2002
Vapor-liquid equilibrium data at 50, 75 and 94 kPa have been determined for the binary system methyl 1,1-dimethylethyl ether + 2-propanol, in the temperature range 308-344 K. The measurements were made in an equilibrium still with circulation of both the vapor and liquid phases. Excess volumes have been also determined from density measurements using a vibrating tube densimeter at 298.15 K. The system exhibits positive deviation from ideal behavior and does not present azeotropy within the range of pressures studied. The excess volume of the system is negative over the whole mole fraction range. The activity coefficients and boiling points of the solutions were well correlated with the mole…
Vapor–liquid equilibria in the systems 3-methylpentane+methyl 1,1-dimethylethyl ether and 3-methylpentane+methyl 1,1-dimethylpropyl ether at 101.3 kPa
1999
Abstract Pure-component vapor pressure of 3-methylpentane and vapor–liquid equilibrium (VLE) for the binary systems of 3-methylpentane with methyl 1,1-dimethylethyl ether (MTBE) and with methyl 1,1-dimethylpropyl ether (TAME) at 101.3 kPa have been measured. Both systems exhibit small positive deviations from ideality. They can be described as regular solutions and do not present azeotrope. The activity coefficients and boiling points of the solutions were correlated with its composition by Wilson, UNIQUAC, NRTL, and Wisniak–Tamir equations.
Isobaric Vapor−Liquid Equilibria of Trichloroethylene with 1-Butanol and 2-Butanol at 20 and 100 kPa
1996
Vapor−liquid equilibria for trichloroethylene + 1-butanol, and + 2-butanol are reported at 20 and 100 kPa. The two systems satisfy the point-to-point thermodynamic consistency test. Both systems show a positive deviation from ideality.
Liquid gas techniques for GC trace analysis
1990
Liquid gases (LG), i.e. low boiling compounds with vapor pressures below 5 bar at room temperature, are introduced as solvents for trace analyses. A system for preparin, diluting and handling LG solutions safely and conveniently in 5 to 500 μl amounts was developed as well as a syringe for direct injection of μl-LG samples into capillary GC. Even technical grade LG are of high purity. GC/FID of LG solutions (starting at −60°C) allows the separation of volatile traces from the solvent peak: e.g., dichloromethane can be measured in the picogram range.