Yield-stress fluids foams: flow patterns and controlled production in T-junction and flow-focusing devices.

We study the formation of yield-stress fluid foams in millifluidic flow-focusing and T-junction devices. First, we provide a phase diagram for the unsteady operating regimes of bubble production when the gas pressure and the yield-stress fluid flow rate are imposed. Three regimes are identified: a co-flow of gas and yield-stress fluid, a transient production of bubble and a flow of yield-stress fluid only.

Bubble Formation in Yield Stress Fluids Using Flow-Focusing and T-Junction Devices.

We study the production of bubbles inside yield stress fluids (YSFs) in axisymmetric T-junction and flow-focusing devices. Taking advantage of yield stress over capillary stress, we exhibit a robust break-up mechanism reminiscent of the geometrical operating regime in 2D flow-focusing devices for Newtonian fluids. We report that when the gas is pressure driven, the dynamics is unsteady due to hydrodynamic feedback and YSF deposition on the walls of the channels.

Retreatment of silicon slurry by membrane processes.

The purpose of the present study is to develop a process to regenerate the polish liquid used in Chemical and Mechanical Polishing (CMP), called "slurry", and more specifically Silicon CMP slurry. Physico-chemical analyses show a considerable dilution of slurry through washing waters used in polishing. Thus, this effluent has been characterised for a better identification of the deviations from the slurry of reference (Point Of Use).

Methodology for constructing a colour-difference acceptability scale.

Observers were invited to report their degree of satisfaction on a 6-point semantic scale with respect to the conformity of a test colour with a white reference colour, simultaneously presented on a PDP display. Eight test patches were chosen along each of the +a*, -a*, +b*, -b* axes of the CIELAB chromaticity plane, at Y = 80 ± 2 cd.m(-2) .

[Anterior open bite: the role of the infra-alveolae in its diagnosis and treatment].

Anterior open-bites may be skeletal, alveolar or mixed. The infra-alveolae is always due to a postural or functional muscular cause and the clinical examination plays an important part in the diagnosis. Delaire's cephalometric analysis can define the type of infra-alveolae.