Densities and excess molar volumes of mixtures containing diesel,biodiesel and alkanols at temperatures from 288.15 to 313.15 K

The present work is focusing on the synthesization and physico-chemical properties of Jatropha curcas biodiesel with diesel and alcohols.The densities of binary diesel (2)+1-alkanols (C_3 or C_4)(3) and ternary Jatropha curcas biodiesel (1)+diesel (2)+1-alkanols (C_3or C_4)(3) blends have been reported over full range of composition at temperatures within range 288.15 to 313.15 K.Also densities of Jatropha curcas biodiesel (1)+diesel or 1-alkanols (C_3 or C_4)(2) blends have been measured at 313.15 K.Excess molar volumes,V~E,V~E_(123)of binary and ternary blends were calculated from the measured data and the derived properties were correlated to composition using Redlich–Kister equation.A reasonable agreement was found between the measured and estimated values.Further,densities and excess molar volumes data were reasoned to discuss molecular interactions taking into consideration effect of composition and temperature.     

308.15 K时N,N-二甲基甲酰胺中咪唑啉酮衍生物们的热动力学性质(英文)

Density,ultrasonic velocity and viscosity of imidazolinone derivatives are studied in dimethyl formamide(DMF) at 308.15 K.From the experimental data,various acoustical parameters,such as specific impedance Z,isentropic compressibilityκs,Rao's molar sound function Rm,van der Waals constant b,relaxation strength r,intermolecular free length Lf,internal pressureπ,solvation number Sn,relative association RA,etc.are evaluated,which helps in understanding the molecular interactions occurring in these solutions.     

Thermodynamic properties of metamizol monohydrate in pure and binary solvents at temperatures from (283.15 to 313.15)K

The thermodynamic properties of metamizol monohydrate in pure solvents (methanol,ethanol,n-propanol and isopropanol) and two binary mixed solvent systems including (methanol + ethanol) and (methanol +isopropanol) were measured from 283.15 K to 313.15 K by gravimetric method under atmospheric pressure thought as 0.1 MPa.The modified Apelblat equation,the CNIBS/R-K equation,the Hybrid model and the NRTL model were used to correlate the solubility of metamizol monohydrate,respectively.The results show that the solubility of metamizol monohydrate in all the tested solvents increases with the rising temperature which means that it has temperature dependence.What's more,the effects of solvent components of the binary solvent mixtures on solubility were discussed,it illustrates that the increasing of the molar fraction of methanol gives the system a greater dissolving power.Furthermore,according to the NRTL model,the enthalpy,the Gibbs energy and the entropy of the mixing process were also obtained and discussed.     

Viscometric studies of poly(N‐vinyl‐2‐pyrrolidone) in water and in water and 0.01% bovine serum albumin at 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, and 313.15 K

Viscosity and density studies for 0.01–0.14% (w/w) poly(N‐vinyl‐2‐pyrrolidone) (PVP) in water and in water and 0.01% bovine serum albumin (BSA) were conducted at 283.15, 288.15, 293.15, 298.15, 303.15, 308.15, and 313.15 K. The viscosity coefficients and the activation‐energy, free‐energy, enthalpy, and entropy changes were calculated from viscosity data for viscous flow. On this basis, PVP–PVP, PVP–BSA, PVP–water, and BSA–water interactions and PVP and BSA shape factors were investigated and rationalized in terms of the water structure. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1001–1015, 2003     

Densities,ultrasonic speeds,refractive indices,and COSMO analysis for binary mixtures of dichloromethane with acetone and dimethylsulfoxide at T = (298.15, 303.15, and 308.15) K

Experimental densities (ρ), ultrasonic speeds (u), and refractive indices (n_D) of binary mixtures of dichloromethane (DCM) with acetone (ACT) and dimethylsulfoxide (DMSO) were measured over the whole composition range at T?=?298.15, 303.15, and 308.15?K. From the experimental data, excess molar volume (V^E), deviations in isentropic compressibility (Δk_s), deviations in intermolecular free length (ΔL_f), deviations in refractive index (Δn_D), and deviations in ultrasonic speed (Δu) were calculated. Moreover, the Benson–Kiyohara theory was applied to the binary mixtures to obtain the theoretical Δk_s values. The COSMO calculations depending on density functional theory were utilized to estimate the σ-profiles for the DCM, ACT, and DMSO. The interpreted σ-profile trends were found supportive with the experimental findings. Applicability of different empirical and semi-empirical relations of refractive index data were tested against the measured results, and good agreement has been obtained. The possible results of intermolecular molecular interactions among mixture components were interpreted.     

288.15K-308.15K(Poloxamerl88+乙醇/丙酮+水)三元体系的密度和黏度

The densities and viscosities of ternary systems(Poloxamer 188+ethanol/acetone+water)were meas- ured at 288.15,293.15,298.15,303.15,308.15 K and atmospheric pressure for different mass fractions of Poloxamer 188(0 to 0.02)in aqueous solution and different solvent volume fractions of ethanol/acetone(0 to 0.3)in Poloxamer 188 aqueous solution.The densities were measured by a pycnometer,while the viscosities were measured using two Ubbelohde capillary viscometers.The correlations of density and viscosity of these ternary systems are obtained by fitting the experimental data at different temperatures,mass fractions and volume fractions.     

Densities and excess volumes of aqueous monoethanolamine and diisopropanolamine systems at atmospheric pressure from 303.15 K to 333.15 K

The densities of water+monoethanolamine (MEA), water+diisopropanolamine (DIPA), DIPA+MEA binary systems and water+DIPA+MEA ternary system were measured over the full range of composition at temperatures from 303.15 K to 333.15 K by using an Anton Paar digital vibrating tube density meter (DMA4500). The experimental excess volumes were obtained from the experimental density results and fitted using the Redlich-Kister-Muggianu expression. The parameters obtained from the binary excess volume data were used for the correlation of ternary system with one additional ternary parameter for each isotherm. All investigated binary and ternary systems are completely miscible, because the values of excess volume are negative under the examined conditions.     

Volumetric study of aqueous solutions of poly(ethylene glycol) from 283.15 to 313.15 K and at 0.1 MPa

Density measurements of binary aqueous solutions of poly(ethylene glycol), with a nominal average molecular weight of 6000, were used to determine the specific volumes of the solutions with solute‐to‐solvent mass ratios (mass of the solute/mass of the solvent) of 0.0483–0.5493 and at seven different temperatures (283.15, 285.15, 293.15, 298.15, 303.15, 308.15, and 313.15 K). The difference between the specific volume of a solution and the specific volume of a pure solvent, at a given temperature, was expanded by a virial‐type equation, in terms of the solute concentration. The first‐order coefficient was the partial specific volume of a solute at infinite dilution. The higher order coefficients corresponded to the contribution of pairs, triplets, and higher order solute aggregates according to the constant‐pressure theory of solutions. The functional dependence of the virial coefficients on the temperature was examined in terms of solute–solute and solute–solvent interactions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2685–2689, 2004     

Experimental data and modeling for excess enthalpies of 2-Pentanol with n-alkanes(C7–C9) at T =(293.15, 298.15 and 303.15) K

Excess molar enthalpies, H~E, for the binary mixtures of 2-pentanol with n-alkanes(n-heptane, n-octane, and nnonane) have been determined at three different temperatures T =(293.15, 298.15 and 303.15) K and normal atmospheric pressure over the entire composition range using a Calvet microcalorimeter. All mixtures show endothermic mixing with the maximum values of the excess enthalpies occurring in the n-alkane-rich region. The H~Edata are smoothed using Redlich–Kister equation. The applicability of the Treszczanowicz–Benson, ERAS,Renon–Prausnitz and Chen–Bagley models to correlate H~Eof studied mixtures is tested, and the agreement between experimental and theoretical results is satisfactory. Each model includes a self-association equilibrium constant that represents hydrogen bonding and an adjustable parameter that reflects physical interactions.     

Vapor-liquid equilibrium,excess gibbs energy and excess enthalpy of 1, 3 dioxolane-methylcyclohexane at t = 313.15 k

Data on vapor-liquid equilibrium and enthalpy of mixing H^E are, obtained for the mixture 1, 3 dioxolane-methylcyclohexane at 313.15 K (40.0°C). Correlation of the data is given by using Redlich-Kister expressions and the excess functions G^E = RT(X₁ In γ₁ + X₂ In γ₂) and TS^E = H^E - G^E are thereby calculated. A comparison is made between this mixture and those formed by 1, 3 dioxolane with cyclohexanol and cyclohexanone.     

Diffusion coefficients of aluminium chloride in aqueous solutions at 298.15, 303.15 and 315.15 K

Mutual diffusion coefficients (interdiffusion coefficients) have been determined for aluminium chloride in water at 298.15, 303.15 and 310.15 K at concentrations from 0.002 to 0.010 mol dm⁻³ together with molar conductivity values. The diffusion coefficients were obtained by using a conductimetric open-ended capillary cell. The experimental data were discussed on the basis of the Onsager-Fuoss model. The Nernst diffusion coefficients derived from diffusion 1.208 × 10⁻⁹ and 1.701 × 10⁻⁹ m² s⁻¹ and from conductance 1.238 × 10⁻⁹ and 1.692 × 10⁻⁹ m² s⁻¹, at two temperatures 298.15 and 310.15 K, respectively, agree well each other.     

The effect of temperature on phase equilibria of polyethylene glycol (PEG8000)-K2SO4-H2O at T=(288.15, 298.15, 308.15) K

The phase behavior of potassium sulfate (K₂SO₄) in polyethylene glycol with molecular weight 8000 (PEG8000) and water (H₂O) mixed solvent at 288.15, 298.15, and 308.15 K were determined. According to the results, when the temperature are 288.15 and 298.15 K, there is only a solid-liquid phase equilibrium relationship in the system, and the phase diagrams are both divided into three parts which respectively are the regions of unsaturated homogeneous liquid (L), one liquid and one solid K₂SO₄ (L + S) and one liquid and two solids K₂SO₄ and PEG8000 (L + 2S). The solubility of K₂SO₄ in PEG8000-H₂O mixed solvent decreased with the addition of the PEG8000 in the solution. Comparing the diagrams of 288.15 and 298.15 K, the sizes of regions of (L) and (L + S) increased and that of (L + 2S) decreased with the increase of temperature. While at 308.15 K, solid-liquid and liquid-liquid equilibrium coexist, and there are six parts in the complete phase diagram at 308.15 K, adding the areas of one liquid and one solid K₂SO₄ (L + S), two liquids (2 L), two liquids and one solid K₂SO₄ (2 L + S). The equations developed by Merchuk, Hu, and Jayapal were used to fit the binodal curves data of the system at 308.15 K, meanwhile, the experimental tie-line data of the system at 308.15 K were correlated by Othmer-Tobias equation and Bancroft equation.     

Long-term effect of diesel degradation on polyoxymethylene at different temperatures

Diesel is an important fuel, partly because of the longevity and cleanliness of diesel engines. Often, polymers are in direct contact with diesel and understanding compatibility is critical. Polyoxymethylene (POM) is a thermoplastic used to manufacture automotive fuel pump gears and rotors due to its low coefficient of friction and thermal and dimensional stability. In this study, tensile tests were performed on plain and glass fiber reinforced (POM and POMGF) after immersion in diesel at different temperatures (−10°C, 23°C, and 60°C) for 1000, 2000, 3000, 5000, and 10 000 hour. A mathematical model was developed using data from just three tensile stress-strain curves obtained at two different fluid temperatures and three different immersion times. Model and experimental results show good agreement with one another for all conditions tested.     

Polycondensation of orthosilicic acid in hydrothermal solutions at different temperatures,pH values,and ionic strengths

The kinetics of polycondensation of orthosilicic acid in hydrothermal solutions is investigated at different temperatures, pH values, and ionic strengths. The equations approximating the time dependence of the polycondensation and the dependence of the polycondensation rate constant on the ionic strength of the solution are determined by the mathematical processing of the experimental data. The experimental data on the kinetics of the inverse process, i.e., the dissolution of colloidal silica, are obtained at different temperatures and pH values.     

Determination of standard pH values for potassium hydrogen phthalate reference buffer solutions in 10, 20, 50, 64 and 84.2 wt per cent methanol/water mixed solvents at temperatures from 283.15 to 313.15 K

Standard pH⁰ values for 0.05 mol kg^?1 potassium phthalate reference buffer solutions in 10, 20, 50, 64 and 84.2 wt % methanol/water solvent mixtures have been obtained from cells without transport, in the temperature range 283.15–313.15 K. The consistency of results has been analysed by a new method of multilinear regression of the quantity p(a_Hγ_Cl) as a function of both temperature and solution composition. The pH° values found can be reproduced within ± 0.01 by the equation pH⁰ = 4.00 + 4.38x ? 5.02x² + 4.23x³ + 0.13z ? 0.91xz, where x = mole fraction of methanol in the solvent mixture, z = (T ? θ)/θ and θ = 298.15 K. Subsidiary values of the first ionization constant of o-phthalic acid in the above solvent mixtures have also been obtained by the buffered cell method.     

Measurement and correlation of liquid-liquid equilibrium for the ternary system (water + 1,2-dichloroethane + sulfolane) at 288.15, 298.15, and 308.15 K

Sulfolane is an important aprotic polar solvent. Liquid-liquid equilibrium(LLE) data for the ternary systems of water + 1,2-dichloroethane + sulfolane were measured at temperatures of 288.15, 298.15 and 308.15 K under the atmospheric pressure. The distribution coefficient and selectivity were determined from the measured LLE data, which showed that 1,2-dichloroethane is a suitable extractant for the recovery of sulfolane from its aqueous solution. The nonrandom two-liquid(NRTL) model and the uni...     

Solubility of argon in acetone + water mixed solvent at 288.15, 298.15 and 308.15 K

Solubilities of argon were determined in acetone + water mixed solvent over the full range of composition using a static method. The gas solubilities were measured at three temperatures of 288.15, 298.15 and 308.15 K. The solubility dependence on the temperature in the mixed solvent was measured and discussed, and the similarity between excess quantities of mixed solvent and those of gas solubilities was examined. The order of gas solubility of argon in acetone + water mixed solvent at the three different temperatures was 288. 15 > 298.15 > 308.15 K in the composition range of 0 ≤ x₂2 ≤ 0.15. However, the reverse relationship with temperature was observed in the range of composition of 0.15 < x₂ ≤ 1.0. For all solubility curves, maximum and minimum values of solubility were observed at lower temperatures, but not at higher temperatures. Furthermore, the excess Ostwald coefficients on the basis of volume fraction which express the non-ideality of gas solubility in non-ideal solutions were defined, and they were expressed by a polynomial equation of the Redlich-Kister (1948) type.     

Synergistic effect between amino sulfonate amphoteric surfactant and octylphenol polyoxyethylene ether (10) in aqueous solutions with different acidicities: consideration of different thermodynamic models

The micellization behavior of binary mixtures of sodium n‐dodecyl diamine sulfonate (C12AS) and octylphenol polyoxyethylene ether (10), OP‐10, in aqueous solutions at pH 3.5, 6.0, and 8.5 was investigated, and the values of mixed critical micelle concentration (C^M) were determined by both UV–vis spectroscopy using pyrene as a probe and by tensiometry. Within the framework of the pseudophase separation model, four thermodynamic models were adopted to describe the micellization parameters including the interaction parameters (β₁₂) between two surfactants, the components in real and ideal mixed micelles, the activity coefficients in mixed micelles, the thermodynamic parameters, and the thermodynamic stability. The experimental values of C^M, inferior to the ideal values, show nonideal mixing; the negative values of β₁₂ obtained from Rubingh's, Rodenas's, and Motomura's models mean the synergistic effect. Although there exist some divergences in the micellization parameters predicted by the three treatments, similar results were obtained, indicating the validity of these models in this investigation. Based on the calculation errors, Rubingh's model is best to describe the interacting behavior between the two surfactants in this investigation. Thermodynamic parameters predicted by the three treatments show a spontaneous process of micellization and an entropic contribution in the formation of mixed micelles. Different acidities of solutions result in different stabilities of micellization. The stability in feeble acidic solution is higher than in acidic or basic solution, and the stability in basic solution is slightly superior to that in acidic solution. All the above described phenomena can be explained rationally by the electrostatic effect of head groups of C12AS, the steric effect of head group for two surfactants, the molecular structures of surfactants, the influence of added counterion, and so on. © 2015 Society of Chemical Industry     

四元体系（Li+， Mg2+//Cl-， borate-H2O）308.15 K相平衡与相图研究

采用等温溶解平衡法,开展四元体系Li⁺, Mg²⁺//Cl^-, borate–H₂O固液相平衡与相图研究,测定平衡溶液的液相组成、密度、折射率和pH。该四元体系相图中存在的盐类矿物为：LiCl·H₂O、Li₂B₄O₇·3H₂O、 MgCl₂·6H₂O、Mg₂B₆O₁₁·15H₂O和锂光卤石LiCl·MgCl₂·7H₂O,其中锂光卤石LiCl·MgCl₂·7H₂O是异成分复盐,溶液中MgCl₂存在下章氏硼镁石（MgB₄O₇·9H₂O）不稳定,转化为多水硼镁石（Mg₂B₆O₁₁·15H₂O）。多水硼镁石结晶区最大,表明镁硼酸盐易于结晶析出,而锂光卤石结晶区最小。采用Pitzer热力学模型对该四元体系的溶解度进行理论预测,计算相图与实验相图吻合较好。该四元体系的稳定相平衡与相图研究,可为含锂硼盐湖老卤中锂、镁、硼产品开发及其综合利用提供理论依据。     

Volumetric,ultrasonic and viscometric studies of binary liquid mixures of N-ethylaniline + chlorobenzene, + Bromobeneze, + 1, 2-dichlorobenzene + 1, 3-dichlorobenzene+1, 2, 4-trichlorobenzene at 303.15 and 308.15K

We measured densities (ρ), ultrasonic speeds (u) and viscosities (η) for binary binary mixtures of N-ethylaniline (N-EA) with chlorobenzene (CB), bromobenzene (BB), 1,2-dichlorobenzene (1,2-DCB), 1,3-dichlorobenzene (1,3-DCB), and 1,2,4-trichlorobenzene (1,2,4-TCB) and their pure liquids at 303.15 K and 308.15 K. These experimental data were used to calculate the excess volume (V ^E ), deviations in ultrasonic speeds (Δu), deviation in isentropic compressibility (Δ κ _s ), deviation in intermolecular free length (ΔL _f ), deviation in acoustic impedance (ΔZ), deviation in viscosity (Δη) and excess Gibbs free energy of activation of viscous flow (G* ^E ). The variations of these properties with composition of binary mixtures suggest loss of dipolar association, difference in size and shape of the component molecules, dipole-dipole interactions and hydrogen bonding between unlike molecules. The viscosity data were correlated with Grunberg and Nissan, Katti and Chaudhri, and Hind et al. equations and the results were compared with the experimental results. The excess parameters were fitted to the Redlich-Kister polynomial equation using multi parametric nonlinear regression analysis to derive the binary coefficients and to estimate the standard deviation.