The self-diffusion of parabens (methyl-, propylparaben) and tetramethylsilane in the binary solvent carbon tetrachloride – Co-solvent (methanol‑d4, acetone‑d6) at 278, 298 and 318 K
The spin–lattice relaxation time has been measured at 33 MHz as a function of temperature for the liquid crystal MBBA and mixtures with carbon tetrachloride. The behaviour of T1, close to the nematic–isotropic transition can be explained if the correct order fluctuation dependence is included. Diffusion constants calculated from fits to the self-diffusion contribution to relaxation are in agreement with existing results.
The self-diffusivity tensor in homogeneously sheared dense granular flows is anisotropic. We show how its components depend on solid fraction, restitution coefficient, shear rate, and granular temperature.
AbstractAggregation numbers were calculated based on measurements of the self-diffusion coefficients, the effective hydrodynamic radii of micelles and aggregates of oxyethylated alkylphenols in aqueous solutions. On the assumption that the radii of spherical micelles are equal to the lengths of fully extended neonol molecules, the limiting values of aggregation numbers corresponding to spherically shaped neonol micelles were calculated. The concentration and temperature ranges under which spherical micelles of neonols are formed were determined.
Self-diffusion scalings in dense granular flows