Viscosity of binary mixtures of cycloalkane with cycloalkane, alkane and aromatic hydrocarbon at 303.15 K

The viscosity ? for eighteen binary mixtures cyclopentane + cyclohexane and + cyclooctane; cyclohexane + cycloheptane, + cyclooctane, + methylcyclohexane, + n-hexane, + n-heptane, + n-octane, + i-octane, + benzene, + toluene, + ethylbenzene, + p-xylene, and + propylbenzene; methylcyclohexane + n-hexane, + i-octane, and + benzene; and cyclooctane + benzene have been reported at 303.15 K over the entire range of composition. The viscosity deviations ?? and excess Gibbs energy of activation ?G*E of viscous flow based on Eyring's theory have been calculated. The effects of molecular sizes and shapes of the component molecules and of interaction energy in the mixture have been discussed. The viscosity data have been correlated with the equations of Grunberg and Nissan, Hind, McLaughlin and Ubbelohde, Tamura and Kurata, Katti and Chaudhri, McAllister, Heric and Brewer, and of Auslaender.

Speeds of sound and isentropic compressibilities of binary mixtures containing trialkylamines with alkanes and mono-alkylamines at 303.15 and 313.15 K

Isentropic compressibilities ?S, and excess isentropic compressibilities ?SE have been determined from measurements of speeds of sound u and densities ? of 14 binary mixtures of triethylamine (TEA) and tri-n-butylamine (TBA) with n-hexane, n-octane, iso-octane, n-propylamine, n-butylamine, n-hexylamine and n-octylamine. The relative magnitude and sign of ?SE have been interpreted in terms of molecular interactions and interstitial accommodation. The values of ?SE for TEA + alkane are positive while for TBA + alkane are negative. The values of ?SE for TEA + primary amine become progressively less positive and eventually to negative with the increase in chain length of alkylamine. In case of TBA + primary amine, the values of ?SE increase from n-propylamine to n-butylamine, and then decrease with chain length of primary amine. The experimental speeds of sound u have been analyzed in terms of collision factor theory, free length theory and Prigogine–Flory–Patterson statistical theory of solutions.

Speeds of sound, isentropic compressibilities, and excess molar volumes of cycloalkanes, alkanes and aromatic hydrocarbons at 303.15 K. II. Results for cycloalkanes+aromatic hydrocarbons

The speeds of sound u, isentropic compressibilities ?S, molar sound functions R, excess isentropic compressibilities ?SE and excess molar volumes VE for eight binary mixtures of cyclopentane, cyclohexane, cyclooctane and methylcyclohexane with benzene and of cyclohexane with toluene, ethyl benzene, p-xylene and propyl benzene at 303.15 K are reported. The effects of molecular sizes and shapes of the component molecules and of interaction energy in the mixture have been discussed. The Prigogine–Flory–Patterson theory has been applied to analyze the present binary mixtures along with the mixtures of cis- and trans-decalins with benzene and toluene taken from the literature.

Densities, speeds of sound, isentropic compressibilities, refractive indices and viscosities of binary mixtures of tetrahydrofuran with hydrocarbons at 303.15 K

Isentropic compressibilities, Rao's molar sound functions, molar refractions, excess isentropic compressibilities, excess molar volumes, viscosity deviations and excess Gibbs energies of activation of viscous flow for seven binary mixtures of tetrahydrofuran (THF) with cyclohexane, methylcyclohexane, n-hexane, benzene, toluene, p-xylene and propylbenzene over the entire range of composition at 303.15 K have been derived from experimental densities, speeds of sound, refractive indices and viscosities. The excess partial molar volumes of THF in different solvents have been estimated. The experimental results have been analyzed in terms of the Prigogine–Flory–Patterson theory.

Densities, speeds of sound, isentropic compressibilities, refractive indexes, and viscosities of tetrahydrofuran with haloalkane or alkyl ethanoate at T = 303.15 K

Isentropic compressibilities ?S, excess isentropic compressibilities image, excess molar volumes VE, viscosity deviations ??, and excess Gibbs energy of activation of viscous flow ?G*E for nine binary mixtures of C4H8O with CCl4, CHCl3, CHCl2CHCl2, 1-C6H13Cl, 1-C6H13Br, CH3CO2CH3, CH3CO2C2H5, CH3CO2C4H9, and CH3CO2C5H11 at 303.15 K have been derived from experimental densities ?, speeds of sound u, refractive indexes nD and viscosities ?. The limiting values of excess partial molar volumes of C4H8O at infinite dilution image in different solvents have been estimated. The results obtained for dynamic viscosity of binary mixtures were used to test the semi-empirical relations of Grunberg–Nissan, Tamura–Kurata, Hind–McLaughlin–Ubbelohde, Katti–Chaudhri, McAllister, Heric, and Auslaender. Finally, the experimental refractive indexes were compared with the predicted results for Lorentz–Lorenz, Dale–Gladstone, Eykman, Arago–Boit, Newton, Oster, Heller, and Wiener equations.

Speeds of sound, isentropic compressibilities, viscosities, and excess molar volumes of binary mixtures of alkanoates with tetra- and trichloromethanes at 303.15 K

Speeds of sound u, isentropic compressibilities ?S, viscosities ?, excess isentropic compressibilities ?SE, excess molar volumes VE, viscosity deviations ??, and excess Gibbs energies of activation ?G*E of viscous flow have been investigated for six binary mixtures of diethyl malonate, diethyl bromomalonate, and ethyl chloroacetate with tetra- and trichloromethane at 303.15 K. The values of ?SE, VE, ??, and ?G*E are highly dependent on the type of components involved and the composition curves are unsymmetrical. The results obtained for viscosity of binary mixtures were used to test the semi-empirical relations of Grunberg-Nissan, Tamura-Kurata, Hind-McLaughlin-Ubbelohde, Katti-Chaudhri, McAllister, Heric-Brewer and Auslaender. The experimental speeds of sound have been analyzed in terms of collision factor theory and free length theory of solutions.

Association of Caveolin-1 gene polymorphism with kidney transplant fibrosis and allograft failure

Context: Caveolin-1 (CAV1) is an inhibitor of tissue fibrosis.
Objective: To study the association of CAV1 gene variation with kidney transplant outcome, using kidney transplantation as a model of accelerated fibrosis.
Design, Setting, and Patients: Candidate gene association and validation study. Genomic DNA from 785 white kidney transplant donors and their respective recipients (transplantations in Birmingham, England, between 1996 and 2006; median followup, 81 months) were analyzed for common variation in CAV1 using a singlenucleotide polymorphism (SNP) tagging approach. Validation of positive findings was sought in an independent kidney transplant donor-recipient cohort (transplantations in Belfast, Northern Ireland, between 1986 and 2005; n=697; median follow-up, 69 months). Association between genotype and allograft failure was initially assessed by Kaplan-Meier analysis, then in an adjusted Cox model.
Main Outcome Measure: Death-censored allograft failure, defined as a return to dialysis or retransplantation.
Results: The presence of donor AA genotype for the CAV1 rs4730751 SNP was associated with increased risk of allograft failure in the Birmingham group (donor AA vs non-AA genotype in adjusted Cox model, hazard ratio [HR], 1.97; 95% confidence interval [CI], 1.29-3.16; P=.002). No other tag SNPs showed a significant association. This finding was validated in the Belfast cohort (in adjusted Cox model, HR, 1.56; 95% CI, 1.07-2.27; P=.02). Overall graft failure rates were as follows: for the Birmingham cohort, donor genotype AA, 22 of 57 (38.6%); genotype CC, 96 of 431 (22.3%); and genotype AC, 66 of 297 (22.2%); and for the Belfast cohort, donor genotype AA, 32 of 48 (67%); genotype CC, 150 of 358 (42%); and genotype AC, 119 of 273 (44%).
Conclusion: Among kidney transplant donors, the CAV1 rs4730751 SNP was significantly associated with allograft failure in 2 independent cohorts.