首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
3.
4.
The densities and speeds of sound of (cyclohexane + nonane) were measured at four temperatures from 298.15 K to 328.15 K, and the respective values of excess volumes and adiabatic compressibility were calculated. Thereafter, the densities for the last system were measured at elevated pressures (0.1 to 40) MPa at four temperatures over the range 298.15 K to 328.15 K with a high-pressure apparatus. The high-pressure density data were fitted to the Tait equation and the isothermal compressibilities were calculated with a novel procedure with the aid of this equation. The low- and high-pressure values of calculated from the density data show that the deviations from ideal behaviour in the system decrease slightly as the temperature and pressure are raised. The data were fitted to the fourth-order Redlich-Kister equation, with the maximum likelihood principle being applied for the determination of the adjustable parameters.  相似文献   

5.
This paper reports densities and speeds of sound for the binary mixtures of (1,3-dioxolane or 1,4-dioxane) with (2-methyl-1-propanol or 2-methyl-2-propanol) at the temperatures (298.15 and 313.15) K. Excess volumes and excess isentropic compressibility coefficients have been calculated from experimental data and fitted by means of a Redlich-Kister type equation. The ERAS model has been used to calculate the excess volumes of the four systems at both temperatures.  相似文献   

6.
7.
Values of the density and speed of sound were measured for the ternary system (methyl tert-butyl ether + methylbenzene + butan-1-ol) within the temperature range (298.15 to 328.15) K at atmospheric pressure by a vibrating-tube densimeter DSA 5000. Two binary sub-systems were studied and published previously while the binary sub-system (methyl tert-butyl ether + butan-1-ol) is a new study in this work. Excess molar volume, adiabatic compressibility, and isobaric thermal expansivity were calculated from the experimental values of density and speed of sound. The excess quantities were correlated using the Redlich–Kister equation. The experimental excess molar volumes were analyzed by means of both the Extended Real Associated Solution (ERAS) model and the Peng–Robinson equation of state. The novelty of this work is the qualitative prediction of ternary excess molar volumes for the system containing auto-associative compound and two compounds that can hetero-associate. The combination of the ERAS model and Peng–Robinson equation of state could help to qualitatively estimate the real behavior of the studied systems because the experimental results lie between these two predictions.  相似文献   

8.
Density (ρ) and speed of sound (u) of the binary mixtures of tributyl phosphate (TBP) and alcohols (1-octanol, 1-decanol and isodecanol) were measured at temperatures from T (298.15 to 323.15) K over the entire composition range and at atmosphere pressure. Using these experimentally determined quantities, the excess molar volume (VE), deviation in isentropic compressibility (Δκs), internal pressure (pi), and adjusted correlation coefficients have been calculated. The excess molar volume has been fitted to a Redlich–Kister type polynomial equation. The positive or negative deviations shown by the excess quantities and the trend shown by the adjusted correlation coefficients have been interpreted in terms of intermolecular interactions and structure of components.  相似文献   

9.
Densities (ρ) and speed of sound (u) of the binary mixtures of 1-octanol and 1-decanol with dodecane and ternary mixture of {1-octanol + tributyl phosphate (TBP) + dodecane} were measured at temperatures from (298.15 to 323.15) K over the entire composition range and at atmospheric pressure. Using these experimentally determined quantities, the excess molar volume (VE), excess isentropic compressibility (κsE) for the binary mixtures and internal pressure (pi) of (alcohol + dodecane) binary mixtures have been calculated. The deviations shown by the excess quantities have been interpreted in terms of intermolecular interactions and structure of components. Using Hildebrand regular solution theory, several other parameters like the enthalpy and entropy of mixing of the binary components have been obtained. From acoustic measurements, the probable dimerization constant of the alcohols has also been determined. The values of these parameters give an indication of the subtle structural changes that occur in these binary mixtures.  相似文献   

10.
The values of density (ρ), viscosity (η) and speed of sound (u) have been measured for binary liquid mixtures of γ-butyrolactone (GBL), δ-valerolactone (DVL), and ε-caprolactone (ECL) with N-methylacetamide (NMA) over the whole composition range at T = (303.15 to 318.15) K and atmospheric pressure. From these data, excess molar volume (VE), deviation in viscosity (Δη), and deviation in isentropic compressibility (Δκs), are calculated. The results are fitted to a Redlich–Kister type polynomial equation to derive binary coefficients and standard deviations.  相似文献   

11.
The density and speed of sound of L-arginine (0.025–0.2 mol kg?1) in aqueous + D-maltose (0–6 mass% of maltose in water) were obtained at temperatures of (298.15, 303.15 and 308.15) K. The apparent molar volume, limiting apparent molar volume, transfer volume, as well as apparent molar compressibility, limiting apparent molar compressibility, transfer compressibility, pair and triple interaction coefficients, partial molar expansibilities, coefficient of thermal expansion and also the hydration number, were calculated using the experimental density and speed of sound values. The results have been discussed in terms of solute–solute and solute–solvent interactions in these systems. Solute–solvent (hydrophilic–ionic group and hydrophilic–hydrophilic group) interactions were found to be dominating over solute–solute (hydrophobic–hydrophilic group) interactions in the solution, which increases with increase in maltose concentration.  相似文献   

12.
Experimental data on density, viscosity, and refractive index at T = (298.15, 303.15, and 308.15) K, while speed of sound values at T = 298.15 K are presented for the binary mixtures of (methylcyclohexane + benzene), methylbenzene (toluene), 1,4-dimethylbenzene (p-xylene), 1,3,5-trimethylbenzene (mesitylene), and methoxybenzene (anisole). From these data of density, viscosity, and refractive index, the excess molar volume, the deviations in viscosity, molar refraction, speed of sound, and isentropic compressibility have been calculated. The computed values have been fitted to Redlich-Kister polynomial equation to derive the coefficients and estimate the standard errors. Variations in the calculated excess quantities for these mixtures have been studied in terms of molecular interactions between the component liquids and the effects of methyl and methoxy group substitution on benzene ring.  相似文献   

13.
Densities, speeds of sound, viscosities and refractive indices of two binary systems 1-butyl-3-methylimidazolium tetrafluoroborate [bmim][BF4] + methanol and 1-ethyl-3-methylimidazolium tetrafluoroborate [emim][BF4] + methanol, as well as of all pure components, have been measured covering the whole range of compositions at T = (278.15 to 318.15) K and p = 101 kPa. From this data, excess molar volumes, excess isentropic compressibilities, viscosity deviations and refractive index deviations were calculated and fitted to extended versions of the Redlich–Kister equation. Estimated coefficients of these equations taking into account the dependence on composition and temperature simultaneously were also presented.  相似文献   

14.
15.
Densities (ρ), viscosities (η), and speeds of sound, (u) of the binary mixtures of 2-propanol with n-alkanes (n-hexane, n-octane, and n-decane) were measured over the entire composition range at 298.15 and 308.15 K and at atmospheric pressure. Using the experimental values of density, viscosity and speed of sound, the excess molar volumes (V E), viscosity deviations (Δη), deviations in speed of sound (Δu), isentropic compressibility (κ s), deviations in isentropic compressibility (Δκ s), and excess Gibbs energies of activation of viscous flow (ΔG* E) were calculated. These results were fitted to the Redlich–Kister type polynomial equation. The variations of these excess parameters with composition were discussed from the viewpoint of intermolecular interactions in these mixtures. The excess properties are found to be either positive or negative depending on the molecular interactions and the nature of liquid mixtures.  相似文献   

16.
17.
This work reports new experimental density data (954 points) for binary mixtures of 1-heptanol + heptane over the composition range (seven compositions; 0  1-heptanol mole fraction x  1), between 298.15 and 393.15 K, and for 23 pressures from 0.1 MPa up to 140 MPa. An Anton Paar vibrating tube densimeter, calibrated with an uncertainty of ±0.7 kg · m−3 was used to perform these measurements. The experimental density data were fitted with a Tait-like equation with low standard deviations. Excess volumes have been calculated from the experimental data. In addition, the isobaric thermal expansivity and the isothermal compressibility have been derived from the Tait-like equation, provided as supplementary material.  相似文献   

18.
Densities (ρ), viscosities (η) and speeds of sound (u) of the ternary mixture (1-heptanol + tetrachloroethylene + methylcyclohexane) and the corresponding binary mixtures (1-heptanol + tetrachloroethylene), (1-heptanol + methylcyclohexane) and (tetrachloroethylene + methylcyclohexane) at 298.15 K were measured over the whole composition range. The data obtained are used to calculate the excess molar volumes (V E), excess isobaric thermal expansivities (α E), viscosity deviations (Δη), excess Gibbs energies of activation of viscous flow (ΔG *E) and excess isentropic compressibilities (κ S E) of the binary and ternary mixtures. The data from the binary systems were fitted by the Redlich–Kister equation whereas the best correlation method for the ternary system was found using the Nagata equation. Viscosities, speeds of sound and isentropic compressibilities of the binary and ternary mixtures have been correlated by means of several empirical and semi-empirical equations. The best correlation method for viscosities of binary systems is found using the Iulan et al. equation and for the ternary system using the Heric and McAllister equations. The best correlation method for the speeds of sound and isentropic compressibilities of the binary system (1-heptanol + methylcyclohexane) is found using IMR (Van Deal ideal mixing relation) and for the binary system (tetrachloroethylene + methylcyclohexane) it is found using the NR (Nomoto relation) and for the binary system (1-heptanol + tetrachloroethylene) and the ternary system (1-heptanol + trichloroethylene + methylcyclohexane) it is obtained from the FLT (Jacobson free length theory).  相似文献   

19.
The densities and speeds of sound of binary solutions of nitrobenzene, 1-butanol, and anisole with tetra-n-butylammonium picrate have been measured over the full composition range from 298.15 to 371.1 K, in order to study the volumetric behavior of continuously miscible systems, made from an organic fused salt and a molecular organic liquid, at just above the melting point of the salt. The calculated apparent molar volumes and compressibilities are analyzed by using the equations of Petrenko and Pitzer. The thermal expansion coefficients of the above systems are also reported.  相似文献   

20.
Density, refractive index and speed of sound at T=298.15 K and atmospheric pressure have been measured over the entire composition range for (dimethyl carbonate (DMC) + methanol + ethanol) and (DMC + methanol + 1-propanol). Excess molar volumes, changes of refractive index on mixing and deviations in isentropic compressibility for the above systems have been calculated. The calculated quantities are further fitted to the Cibulka equation to estimate the ternary fitting parameters. Standard deviations from the regression lines are shown.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号