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A deposited drop of bovine serum albumin salt solution experiences both gelation and fracturation during evaporation. The cracks appearing at the edge of the gelling drop are regularly spaced, due to the competition between the evaporation-induced and relaxation-induced stress evolution. Subsequently, the mean crack spacing evolves in an unexpected way, being inversely proportional instead of proportional to the deposit thickness. This evolution has been ascribed to the change with time of the average shrinkage stress, the crack patterning being purely elastic instead of evaporation-controlled

Er 3 + diffusion in congruent LiNbO 3 crystal doped with 4.5 mol% MgOBy means of an accurate investigation of the hydrodynamical behavior of the studied liquid, we have been able to perform interdiffusion and pure Soret effect measurements in ͑LiCl, RH 2 O͒ with R ranging from 6 to 100 and temperature from Ϫ60 to 0°C. The interdiffusion coefficient corrected by a thermodynamic factor shows a characteristic evolution with concentration, which is a straightforward consequence of the role of the ions in this direct transport phenomenon. The Soret coefficient has revealed itself to be strongly negative, to increase with temperature, and to exhibit a sharp minimum with concentration. By comparison with measurements in other aqueous alkali chlorides, these results have contradicted the existing theory: negative Soret coefficients do not seem to be associated with poorly organized water. Furthermore, the extremum in the medium concentration range is likely to be related to the polarizing influence of the alkali ions on the outer hydration shells.

Abstract-We have performed holographic interferometry measurements of the dissolution of the (010) plane of a cleaved gypsum single crystal in pure water. These experiments have provided the value of the dissolution rate constant k of gypsum in water and the value of the interdiffusion coefficient D of its aqueous species in water. D is 1.0 × 10 −9 m 2 s −1 , a value close to the theoretical value generally used in dissolution studies. k is 4 × 10 −5 mol m −2 s −1 . It directly characterizes the microscopic transfer rate at the solid-liquid interface, and is not an averaged value deduced from quantities measured far from the surface as in macroscopic dissolution experiments. It is found to be two times lower than the value obtained from macroscopic experiments.