摘要:

A new method for calculating activity coefficients at infinite dilution is proposed, based on extrapolation of the weighted volatility functio ω=x1In (y1/x1)+ x2In (y2/x2), to dilute compositions. The values of ω are calculated from vapor-liquid equilibria data smoothed by an appropriateGefunction. The ω function exhibits very good numerical sensitivity that improves the extrapolation capabilities of an activity coefficient model, when its parameters are adjusted to experimental VLE data instead of a bubble-point pressure fit technique. The results of the proposed method are compared with the results predicted by DECHMA and by MOSCED for 95 systems of known thermodynamic consistency and shown to be more accurate than those of DECHEMA and of equal or better accuracy to those of MOSCED. A mean deviation of 14% is achieved with respect to experiemental data on activity coefficients at infinite dilution.

ISSN:0031-9104    

DOI:10.1080/00319109608030701

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The equation, taking into account the conformational molecular characteristics, is used for the calculation of the viscosity of bromoalkanes. It is shown that the viscosity of the compounds under investigation can be described adequately by means of this equation.

ISSN:0031-9104    

DOI:10.1080/00319109608030702

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Heat of mixing data for the ternary liquid system propan-2-01 + methylacetate + dichloromethane at 298.15 K are reported along with data for the constituent binary systems. Different expressions published in the literature were used to calculate excess enthalpies from the corresponding binary data. The empirical correlation of Tanaka and Tamura gives the best prediction for this system. The UNIFAC group contribution is applied to predict enthalpies, in this case only for binary systems and compared with experimental data.

ISSN:0031-9104    

DOI:10.1080/00319109608030703

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Using the ‘pure base’ calorimetric method, the association enthalpy (ΔfH) of cholesterol and 2-methoxyethanol (MeOEtOH), triethylamine (TEA) or tri-1-butylamine (TBA) in the presence of MeOEtOH (10% mol) has been determined. The addition of 2-methoxyethanol to the amine brings about the same effect as the addition of other simple alcohols (methanol, butan-1-ol). The increase in the association enthalpy of cholesterol and TBA in the presence of MeOEtOH can be caused by MeOEtOH hydroxyl group involved in the formation of mixed associates. In the case of amine with a weak steric hindrance (TEA), such an effect is not observed. The addition of 10 mol% of water or alcohols to N,N-dimethylformamide (DMF) makes no significant change in the cholesterol-DMF association enthalpy. This would suggest that the hydroxyl groups of added R'OH fail to participate in the formation of cholesterol-DMF associates. A slight increase in ΔfH, taking place when water is added to DMF, can be attributed to an increased solvation of the associates being formed.

ISSN:0031-9104    

DOI:10.1080/00319109608030704

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

Isobaric Vapour-Liquid equilibria of p-xylene + 1,2-dichloroethane, p-xylene + 1,1,1-trichloroethane and p-xylene + 1,1,2,2,-tetrachloroethane, binary mixtures measured at 66.5 kPa are reported. Activity coefficients are evaluated and correlated.

ISSN:0031-9104    

DOI:10.1080/00319109608030705

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

The ultrasonic velocity, density and viscosity of carbonato-bis(ethylene diamine) cobalt(III) perchlorate solution in water and 10%, 20%, 30%, 40% glycerol-water mixtures have been measured at 303.15 K. Various acoustic parameters such as isentropic compressibility, free length, acoustic impedance have been obtained from the experimental data for all the solutions. The nature of variation of these acoustic parameters give information about the type of interaction taking place in these systems. The co-ordination complex behaves as a structure breaker in glycerol-water mixed solvents.

ISSN:0031-9104    

DOI:10.1080/00319109608030706

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor

摘要:

This is a scanned image of the original Editorial Board page(s) for this issue.

ISSN:0031-9104    

DOI:10.1080/00319109608030700

出版商:Taylor & Francis Group    

年代:1996

数据来源: Taylor