Transport properties of dense fluid argon

We calculate using molecular dynamics simulations the transport properties of realistically modeled fluid argon at pressures up to $\simeq 50GPa$ and temperatures up to $3000K$. In this context we provide a critique of some newer theoretical predictions for the diffusion coefficients of liquids and a discussion of the Enskog theory relevance under two different adaptations: modified Enskog theory (MET) and effective diameter Enskog theory. We also analyze a number of experimental data for the thermal conductivity of monoatomic and small diatomic dense fluids.Comment: 8 pages, 6 figure

Universal relations between critical amplitudes : the experimental determination of R+ξ

We have experimentally determined the universal constant R +ξ (for the class of fluids n = 1, d = 3) concerning the amplitude of the diverging part of the specific heat. For the first time a good accuracy is obtained, which allows the experimental values in 3 binary fluids (R+ξ = 0.29 ± 0.04; 0.280 ± 0.011 ; 0.255 ± 0.013) to be favourably compared to the renormalization group result (0.269 6 ± 0.000 8) and the high temperature series expansion value (0.253 ± 0.001), the renormalization group result giving a better agreement with the experimental results.Nous avons déterminé expérimentalement la constante universelle R +ξ (pour la classe des fluides n = 1, d = 3) concernant l'amplitude de la partie divergente de la chaleur spécifique. Pour la première fois une bonne précision est atteinte, permettant aux valeurs dans 3 fluides binaires (R+ξ = 0,29 ± 0,04 ; 0,280 ± 0,011; 0,255 ± 0,013) d'être comparées à celles du groupe de renormalisation (0,269 6 ± 0,000 8) et des séries haute temperature (0,253 ± 0,001), la première valeur étant en meilleur accord avec les résultats expérimentaux

Density of 1,1-dichloro-1-fluoroethane (HCFC 141b) as a function of temperature and pressure.

Copyright © 1996 Plenum Publishing Corporation.The density of HCFC 141b has been measured at several temperatures between 260 and 320 K, Mid pressures up to 20 MPa, with a mechanical oscillator densimeter. The densimeter was calibrated with 2,2,4-trimethylpentane, whose density was obtained from a correlating cyuation with 0.3% uncertainty. The density data obtained for HCFC 14H) hits a reproducibility of 0.05% and an uncertainty of 0.3%. The data obtained were fitted to a Tait-type equation which reproduced the experimental densities within 0.11 % and were compared with the data obtained in other works