Volume 42, Issue 3, September 2013
Index of content:
- REGULAR ARTICLES
42(2013); http://dx.doi.org/10.1063/1.4812573View Description Hide Description
The paper presents a new reference correlation for the viscosity of squalane at 0.1 MPa. The correlation should be valuable as it is the first to cover a moderately high viscosity range, from 3 to 118 mPa s. It is based on new viscosity measurements carried out for this work, as well as other critically evaluated experimental viscosity data from the literature. The correlation is valid from 273 to 373 K at 0.1 MPa. The average absolute percentage deviation of the fit is 0.67, and the expanded uncertainty, with a coverage factor k = 2, is 1.5%.
New Group-Contribution Approach to Thermochemical Properties of Organic Compounds: Hydrocarbons and Oxygen-Containing Compounds42(2013); http://dx.doi.org/10.1063/1.4815957View Description Hide Description
A new group-contribution approach involving systematic corrections for 1,4-non-bonded carbon-carbon and carbon-oxygen interactions has been proposed. Limits of the applicability of the method, associated with the highly branched structures, were established. Experimental data for enthalpies of formation in the liquid phase, enthalpies of vaporization, and enthalpies of formation in the gas phase for alkanes, alkenes, alkynes, alkylbenzenes, alkanols, ethers, ketones and aldehydes, carboxylic acids, esters, and carbonates were collected and critically evaluated through dynamic data evaluation as implemented in the NIST ThermoData Engine. An automatic procedure for molecular structure “decomposition” was developed, and algorithms for the assessment of expanded uncertainties for the predicted property values were implemented. The combination of these software tools allows for ongoing improvements of the group-contribution parameter set as new experimental data become available. Fifty-two group-contribution parameters and their variances were evaluated for the proposed schema. Based on comparison of critically evaluated and predicted data for all classes of compounds studied, the performance of the new group formulation and associated parameters is superior to that originally suggested by Benson and the update by Cohen without an increase in the number of required parameters.
IUPAC-NIST Solubility Data Series. 99. Solubility of Benzoic Acid and Substituted Benzoic Acids in Both Neat Organic Solvents and Organic Solvent Mixtures42(2013); http://dx.doi.org/10.1063/1.4816161View Description Hide Description
Solubility data are compiled and reviewed for benzoic acid and 63 substituted benzoic acids dissolved in neat organic solvents and well-defined binary and ternary organic solvent mixtures. The compiled solubility data were retrieved from the published chemical and pharmaceutical literature covering the period from 1900 to the beginning of 2013.
42(2013); http://dx.doi.org/10.1063/1.4818980View Description Hide Description
This paper contains new, representative reference equations for the viscosity of n-hexane. The equations are based in part upon a body of experimental data that has been critically assessed for internal consistency and for agreement with theory whenever possible. The correlations are valid from the triple point to 600 K, and at pressures up to 100 MPa. We estimate the expanded uncertainty at a 95% confidence level to be 2% for the liquid phase at temperatures from the triple point to 450 K and pressures to 100 MPa. For the liquid at 450–600 K at pressures to 100 MPa, the expanded uncertainty at the 95% confidence level is 6%, and is 0.3% for the low-density gas at pressures to 0.3 MPa.