Rate of demicellization from the dynamic surface tensions of micellar solutions

Abstract

HOO", although its ring system may lose activity. The possibility of hexagonal coordination for the cobalt ion (only ion in the present study) may allow the effective modification by the carrier through its fifth coordination site to be active at its sixth coordination site. Okura et al.9 assumed that oxidized Co-TPP easily reacts with HOO" (step 2). The face-to-face cobalt porphyrin has been reported to form G¿-superoxo)dicobalt complex, allowing the electrochemical reduction of molecular oxygen to H202.16

Interplay between viscosity and elasticity in freely expanding liquid sheets

“…For CpCl, Γ eq = 5 × 10 −10 mol/cm 2 , and D = 8.6 × 10 −6 cm 2 /s in water (η 0 = 1 mPa s) [33], yielding for a bulk concentration of 5.88 mM, t d = 0.7 ms in pure water. Hence, because D is expected to scale as the inverse of the viscosity, the time scale needed to reach the equilibrium surface tension exceeds the time scale needed to reach the maximal expansion of the sheet for viscosity larger than ∼ 5 mPa s. Consequently, for large viscosity the relevant surface tension of the water/glycerol/CpCl mixtures is expected to be that of water/glycerol mixtures, as observed experimentally.…”

Equilibrium Surface Tension, Dynamic Surface Tension, and Micellization Properties of Lactobionamide-Type Sugar-Based Gemini Surfactants

“…Furthermore, apparent diffusion coefficients can be calculated from long-time dynamic surface tension data using the equation introduced by Hansen and Joos 17,18 :…”

Kinetics of nonionic surfactant adsorption at a fluid-fluid interface from a micellar solution

“…The time-dependent surface coverage in a micellar phase is therefore solution of the system of two coupled equations (5) and (10). Whereas equation (5) describes the kinetics taking place inside the bulk solution and generalizes the results of [3] to a micellar phase, equation (10) which is valid for a submicellar as well as for a micellar solution, describes the adsorption kinetics at the interface.…”

“…Therefore the diffusion equation of the monomers must contain terms that account for the presence of the micelles. Previous theories proposed for this purpose [8,10,11] assume a diffusion-limited adsorption which implies that the interface is in equilibrium at all time with the adjacent solution. But some experiments show a weak concentration dependence of the dynamic surface tension [12] indicating that the adsorption might be kinetically-limited.…”

“…For a micellar solution, we model micelles as sources of surfactant molecules which are present anywhere in the solution and thus violate mass conservation (the bulk volume fraction is now a non-conserved order parameter). We thus assume a diffusion-relaxation equation for the surfactant molecules in the bulk [10,11] …”