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Abstract: The ability of the extended corresponding states principle (ECSP) to predict the self-diffusion coefficients of several types of fluids has been studied. Two versions of the model were compared with the traditional two-parameter corresponding states principle (where the equilibrium shape factors are set to unity): one using the equilibrium shape factors and another one that additionally introduces a correction based on the modified Enskog theory (MET). Ethane was chosen as a reference fluid and the experimental database comprises 3163 points from 37 substances (polar, non-polar and hydrogen-bonding ones). Results show that a third complementary parameter, generated from diffusion data, is necessary to accurately correlate this transport property. [Copyright &y& Elsevier]

Abstract: A modification of an existing correlative equation for self-diffusion coefficients is presented. A free-volume theory for liquids has been corrected to reproduce diffusivities of hard-sphere and Lennard–Jones fluids from low-density limit to melting points, and has been applied to correlate a wide database of non-polar, polar, quantic and hydrogen-bonding substances, although it is unable to fit helium, water and hydrogen fluoride. The adjustable parameters are generalized with available fluid properties, and the three resulting predictive formulas present lower deviations than other correlative equations used in a predictive way for non-quantic and non-associated fluids. [Copyright &y& Elsevier]

The relations between self-diffusion and viscosity for compressed liquids and gases have been reviewed, and a new equation for correlating viscosities over wide ranges of temperature and pressure is proposed. This formula is inspired by the Lennard–Jones Chain model of Yu and Gao for self-diffusion, and represents the viscosities of 15 compounds (1046 data points) with an average absolute deviation of 6.95%. Moreover, as the presented equation and the Yu–Gao model require the same fitting parameters, the ability to calculate self-diffusion coefficients from the viscosity parameter is studied. Some of the classic reviewed relations, such as the Stokes–Einstein formula, are also contrasted with the available experimental data of both transport properties. [Copyright &y& Elsevier]

The relationship between resveratrol (RES) bioavalability and its effect on tumor growth was investigated. Tissue levels of RES were studied after i.v. and oral administration of trans-resveratrol (t-RES) to rabbits, rats, and mice. Half-life of RES in plasma, after i.v. administration of 20 mg t-RES/kg b.wt., was very short (e.g., 14.4 min in rabbits). The highest concentration of RES in plasma, either after i.v. or oral administration (e.g., 2.6 ± 1.0 μM in mice 2.5 min after receiving 20 mg t-RES/kg orally), was reached within the first 5 min in all animals studied. Extravascular levels (brain, lung, liver, and kidney) of RES, which paralleled those in plasma, were always < 1 nmol/g fresh tissue. RES measured in plasma or tissues was in the trans form (at least 99%). Hepatocytes metabolized t-RES in a dose-dependent fashion (e.g., 43 nmol of t-RES/g × min in the presence of 20 μM tRES), which means that the liver can remove circulating RES very rapidly. In vitro B16 melanoma (B16M) cell proliferation and generation of reactive oxygen species (ROS) was inhibited by t-RES in a concentration-dependent fashion (100% inhibition of tumor growth was found in the presence of 5 μM t-RES). Addition of 10 μM H2O2 to B16M cells, cultured in the presence of 5 μM t-RES, reactivated cell growth. Oral administration of t-RES (20 mg/kg twice per day; or included in the drinking water at 23 mg/l) did not inhibit growth of B16M inoculated into the footpad of mice (solid growth). However, oral administration of t-RES (as above) decreased hepatic metastatic invasion of B16M cells inoculated intrasplenically. The antimetastatic mechanism involves a t-RES (1 μM)-induced inhibition of vascular adhesion molecule 1 (VCAM-1) expression in the hepatic sinusoidal endothelium (HSE), which consequently decreased in vitro B16M cell adhesion to the endothelium via very late activation antigen 4 (VLA-4). [Copyright &y& Elsevier]

The molecular diffusion coefficients of 2-nitroanisole, 1,2-dichlorobenzene and tert-butylbenzene in supercritical carbon dioxide and carbon dioxide containing modifiers were determined by using the Taylor–Aris dispersion technique. Experimental values are reported for temperatures ranging from 313 to 333 K and pressures between 15.0 and 35.0 MPa. The influence of pressure, temperature, density and viscosity on the binary diffusion coefficients was examined. The addition of low proportions of methanol and n-hexane as modifiers had an important effect on the diffusion coefficient of the three solutes. [Copyright &y& Elsevier]