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1.
Muhammad Asghar Jamal Muhammad Kaleem Khosa Bushra Naseem Muhammad Zaheer-Ud-Din Majid Muneer 《Physics and Chemistry of Liquids》2016,54(3):384-393
Densities and sound velocities for aqueous monoethanolamine (MEA) system are reported over the entire composition range at different temperatures (298.15, 303.15, 313.15 and 318.15 K). These experimental data have been further used in calculating the excess molar volume, partial molar volumes, isobaric thermal expansion coefficients and the deviation in isentropic compressibility. The excess molar volumes data were fitted to the Redlich–Kister polynomial equation to obtain their coefficients and standard deviations. The partial molar volume at infinite dilution of both water in MEA and MEA in water and have been determined using two different methods. Knowledge of the above properties of these mixtures is a basis for understanding some of the molecular interactions in these systems. From the analysis of the results, the type of interactions between the MEA and water is discussed in terms of the number and size of the alkyl groups attached to the nitrogen atom of MEA. 相似文献
2.
The densities and speeds of sound in pentan-1-ol + octan-1-ol, pentan-1-ol + nonane and hexane + nonane binary systems have been measured over the whole composition range from 293.15 to 313.15 K. For comparison, literature data for the hexane + octan-1-ol mixture have also been analyzed. The quantities determined have been plotted as functions of temperature and composition. The excess molar volumes and excess molar compressions have been interpeted on the basis of the homomorph concept. 相似文献
3.
C. Lafuente V. Rodríguez M. C. López F. M. Royo J. S. Urieta 《Journal of solution chemistry》1994,23(5):561-568
From density measurements over the whole composition range at 25 and 40°C excess molar volumes for binary mixtures of 1,4-dichlorobutane with l-butanol, 2-butanol, 2-methyl-l-propanol or 2-methyl-2-propanol are calculated. VE results were fitted by the method of least squares to a smoothing equation. Excess partial molar volumes and limiting excess partial molar volumes at 25° are also calculated. 相似文献
4.
Excess volumes of binary mixtures of water with methanol, ethanol and 1-propanol were obtained from density measurements at 5 degree intervals from 15 to 35°C over the entire composition range. Excess thermal expansion coefficients, partial molar excess volumes, and expansibilities at 25°C were derived from the results. The significance of these values is discussed in relation to hypothesized structural changes in the mixtures. 相似文献
5.
Excess and excess partial molar volumes of mixing of the system N,N-dibutyl-2-ethylhexylamide (DBEHA) + dodecanol (DDA) were determined at 25, 35, 45, 55 and 65°C. The excess molar volumes exhibit a maxima at each temperature at approximatelyx
DBEHA = 0.3 and a minima close tox
DBEHA = 0.9. The values of the excess volumes in general increase with the temperature. The partial excess molar volumes are calculated from the smoothed data and the results are discussed in the light of postulated amide-alcohol interactions. 相似文献
6.
7.
New experimental data of densities and surface tensions are presented for the binary mixtures of the ionic liquid 1-ethyl-3- methyl imidazolium nitrate([EMIM]NO3) with methanol and ethanol.Measurements were performed at 298.15 K and atmospheric pressure,covering the whole composition range.Excess molar volumes VE and the surface tension deviations Sy have been determined.For the excess molar volumes of binary mixture,there is a region of negative VE at low IL mole fraction,passing through a minimum and then VE increases and becomes positive,showing maximum at higher IL mole fraction.It is shown that the surface tension deviations Sy of[EMIM]NO3 + methanol system are positive but those of[EMIM]NO3 + ethanol system are negative over the entire mole fraction range. 相似文献
8.
New experimental data on the density of three
(0.2393, 0.4856 and 0.7390 mole fraction of ethylbenzene) binary n-heptane+ethylbenzene mixtures have been measured
with a constant-volume piezometer immersed in a precision liquid thermostat.
These new experimental data covering a temperature range from 306 to 527 K
and a pressure range of 0.1 to 11 MPa. The experimental data reported here
have an uncertainty less than 0.06% for the density, 0.05% for the pressure,
15 mK for the temperature, and 0.012% for the concentration. Excess molar
volumes were derived using measured values of density for the mixtures and
for the pure components calculated with reference equation of state for n-heptane (Span and Wagner, 2003) and for the pure
ethylbenzene (Frenkel et al., 2005). The
derived values of excess molar volumes at atmospheric pressure were compared
with the values reported by other authors in the literature. The effect of
pressure on the excess molar volumes was studied. 相似文献
9.
The excess molar volumes and molar refractionsR
12 of 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU)+water have been determined over the entire mole fraction range at 10° intervals from 5 to 45°C and at atmosphere pressure. The excess volumes are all negative and they become more positive with increase of temperature. Limiting partial molar volumes for DMPU in water and water in DMPU are also reported. 相似文献
10.
Densities of glycerol + N,N-Dimethylformamide (DMF) and glycerol + water mixtures have been measured over the full range of compositions at 25 and 35°C. Excess molar volumes and excess partial molar volumes, of each system have been calculated. All mixtures show negative values of the excess molar volume due to increased interactions between unlike molecules. 相似文献
11.
Monika Geppert-Rybczyńska Barbara Hachuła Monika Bucek 《Journal of solution chemistry》2008,37(12):1747-1773
The densities of propan-2-ol + pentan-1-ol, + hexan-1-ol, + heptan-1-ol, + octan-1-ol + nonan-1-ol and speeds of sound in
propan-2-ol + pentan-1-ol, + heptan-1-ol, + nonan-1-ol have been measured over the whole composition range at 298.15 K. Excess
molar functions determined from the experimental data have been plotted as functions of composition. The excess molar volumes
have been interpreted on the basis of the Symmetrical Extended Real Associated Solution Model (S-ERAS). 相似文献
12.
Excess volumes of water-acetonitrile mixtures were obtained from measurements of density over the entire mole fraction range and at 5 degree intervals from 15 to 35°C. Partial molar excess volumes at the five temperatures, excess coefficients of thermal expansion at 25°C and partial molar excess expansibilities at 25°C were derived from the results. The values of the various volumetric properties are compared with data from the literature.Issued as NRCC No. 19500 相似文献
13.
Sonia Freire H. Casas Esther Rilo Luisa Segade O. Cabeza E. Jiménez 《Journal of Thermal Analysis and Calorimetry》2005,80(2):285-288
Summary In this paper we present excess molar volumes and excess molar enthalpies of binary and ternary mixtures containing propyl propanoate, hexane and cyclohexane as components at 298.15 K. Excess molar volumes were calculated from the density of the pure liquids and mixtures. The density was measured using an Anton Paar DMA 60/602 vibrating-tube densimeter. Excess molar enthalpies were obtained using a Calvet microcalorimeter 相似文献
14.
The densities and speeds of sound in the pentan-1-ol + nonan-1-ol, pentan-1-ol + dekan-1-ol, propan-1-ol + hexan-1-ol, and
propan-2-ol + hexan-1-ol binary systems have been measured within the whole composition range at 298.15 K. The quantities
determined from the measurement data have been plotted as functions of composition. The excess molar volumes have been interpreted
on the basis of results of the Symmetrical Extended Real Associated Solution Model (S-ERAS). 相似文献
15.
利用Anton Paar DMA55精密数字密度计测定了288.15, 298.15和308.15 K甘氨酰甘氨酸在蔗糖-水混合溶剂中的密度, 计算了甘氨酰甘氨酸的表观摩尔体积VΦ和极限偏摩尔体积 , 得到了其由纯水溶剂转移至混合溶剂中的迁移偏摩尔体积Δtrs 和理论水化数Nh.根据共球交盖模型, 讨论了迁移偏摩尔体积和水化数的变化规律.结果表明, 甘氨酰甘氨酸带电中心与蔗糖之间的结构相互作用对其迁移体积有正贡献, 且占主导地位.甘氨酰甘氨酸的迁移偏摩尔体积为正值, 且随着蔗糖浓度的增大而增大; 理论水化数随温度升高、蔗糖浓度的增大而减小; 温度升高, 极限偏摩尔体积增大, 迁移偏摩尔体积变化很小. 相似文献
16.
Christophe Coquelet 《Thermochimica Acta》2006,448(1):47-51
Densities of the water + 3-(dimethylamino) propylamine (DMAPA) binary system were measured at atmospheric pressure over the whole range of compositions at temperatures from 283.15 to 353.15 K using Anton Paar digital vibrating glass tube densimeter. The density of this system has been found an increasing function of water composition and a decreasing function of temperature. Excess molar volumes have been correlated using Redlich-Kister equations. Sets of parameters have been determined from experimental data to obtain correlations in the measurement range uncertainty. Partial molar volumes on the whole concentration range have been determined using Redlich-Kister parameters. 相似文献
17.
Densities of four aqueous NaNO3 solutions (0.100, 0.303, 0.580, 0.892 mol-kg–1 H2O) have been measured in the liquid phase with a constant-volume piezometer immersed in a precision liquid thermostat. Measurements were made at ten isotherms between 292 and 573 K. The range of pressure was 0.1–30 MPa. The total uncertainty of density, pressure, temperature, and concentration measurements were estimated to be less than 0.06%, 0.05%, 10 mK, and 0.014%, respectively. Values of saturated densities were determined by extrapolating experimental P- data to the vapor pressure at fixed temperature and composition. Apparent molar volumes were derived using measured values of density for the solutions and for pure water. The apparent molar volumes were extrapolated to zero concentration to yield partial molar volumes at infinite dilution. The temperature, pressure, and concentration dependence of partial and apparent molar volumes were studied. The measured values of density and apparent and partial molar volume were compared with data reported in the literature. 相似文献
18.
Experimental density data of the binary mixtures of N-methyldiethanolamine + (2-aminoethyl)ethanolamine and the ternary mixtures of N-methyldiethanolamine + (2-aminoethyl)ethanolamine + water were reported at atmospheric pressure over the entire composition range at temperatures from 283.15 to 363.15 K. Density measurements were performed using an Anton Paar digital vibrating U-tube densimeter. Excess molar volumes were calculated from the experimental data and correlated as the Redlich-Kister equation for the binary mixtures, and as the Nagata-Tamura equation for the ternary mixtures. Several empirical models were applied to predict the excess molar volumes of ternary mixtures from the corresponding binary mixture values. It indicates that the best agreement with the experimental data was achieved by the Redlich-Kister, Kohler, and Jacob-Fitzner models. 相似文献
19.
Mirtha Orozco Alberto Camacho Salvador Canzonieri 《Physics and Chemistry of Liquids》2018,56(3):353-362
Densities and viscosities of binary liquid mixtures of propyl propanoate + heptane and propyl propanoate + octane at temperatures of 278.15, 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, 313.15, 318.15 and 323.15 K have been measured at atmospheric pressure over the entire range of composition. Using these experimental data, the excess molar volumes and the viscosity deviation have been calculated. The experimental data of density and viscosity at different investigated temperatures were mathematically represented by the Jouyban–Acree model. The mean relative deviation (MRD) was used as an error criterion, and the MRD values for data correlation of density and viscosity at different investigated temperatures are less than 0.03% and 0.50%, respectively. Excess molar volumes and viscosity deviations were correlated with Redlich–Kister equation. The calculated data point out the absence of speci?c interactions between the molecules of different components, which would be slightly weaker compared to the interactions in the pure components. 相似文献
20.
Densities of glycerol (1) + tert-butanol (2) mixtures were measured over the temperature range 293.15 to 348.15 K at atmospheric pressure, over the entire
composition range, with a vibrating tube densimeter. Excess molar volumes, apparent and partial molar volumes of glycerol
and tert-butanol, thermal isobaric expansivities of the mixture and partial molar expansivities of the components were calculated.
The excess molar volumes of the mixtures are negative at all temperatures, and deviations from ideality increase with increasing
temperature. Excess molar volumes were fitted to the Redlich–Kister equation. Partial molar volumes of glycerol decrease with
increasing tert-butanol concentration. The temperature dependence of the partial molar volumes of glycerol is characterized by an inversion
at x
2≈0.7. “Negative expansion” of the limiting partial volumes of glycerol was observed. 相似文献