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Absence of subcritical instabilities and global nonlinear stability for porous ternary diffusive-convective fluid mixtures Phys. Fluids 24, 104101 (2012) Capillary filling dynamics of water in nanopores Appl. Phys. Lett. 101, 153112 (2012) Division by fluid incision: Biofilm patch development in porous media Phys. Fluids 24, 091107 (2012) Core-flood experiment for transport of reactive fluids in rocks Rev. Sci. Instrum. 83, 084501 (2012) On a singular incompressible porous media equationTraditional models, such as the advection-diffusion and the dusty gas models, overlook the contribution of the transition flow regime between the slip and the free molecular flow, on the gas transport in porous media. In this work we demonstrate that, due to the existence of this intermediate regime, the Klinkenberg ͓Drill. & Prod. Prac. 1941, 200 ͑1941͔͒ parameter b depends on the pressure. Reported experiments were used to corroborate such an effect and a formulation that extends the Klinkenberg equation-to include the effect of a region at pore scale where both molecule-molecule and molecule-wall interactions are important-was developed. The mathematical form of the extended Klinkenberg equation remains the same, but the slippage Klinkenberg's parameter b is now a generalized parameter that is a function of Knudsen's number. It was demonstrated that the widely accepted relation between the parameter b and the Knudsen diffusion coefficient is a good approximation just for Knudsen numbers corresponding to the free molecular flow regime. The model proposed in this paper reproduces the experimental data and predicts practical situations where important errors on total flow rate can be expected if the transition flow regime is neglected in the formalism.

: Porcine pancreatic lipase (PPL) was covalently immobilized through the formation of an aromatic Schi † Ïs-base obtained by reaction of the e-amino group of lysine residues in the enzyme and the aromatic aldehyde function of activated supports. The enzymatic activities of di †erent immobilized PPL systems on amorphous and several inorganic supports at di †erent pH AlPO 4 values and temperatures were determined by hydrolysis of ethyl acetate. The nature of the support material critically a †ects the efficiency of enzyme immobilization as well as enzyme stability. All the supports examined, with the exceptions of cellulose and natural sepiolite, exhibited good properties for enzyme attachment.was the best support for enzyme immobilization, giving the AlPO 4 highest percentage binding of enzyme (90%) and the highest retention of enzyme activity after immobilization (92É8%).1998 SCI (

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