Wedge model

Fig. 10.43 Linear wedge model of the mixing chamber near a wing tip.

Fig. 9.7 Snapshots of a re-entrant scroll wave in a 6x6x3 cm isotropic and homogeneous epicardial cuboid (left), and a wedge model of the human left ventricular free wall with similar dimensions, and fiber and sheet orientations giving orthotropy of propagation (right). Both examples use the ten Tusscher— Noble—Noble—Panfilov model [42] for excitation kinetics. In the wedge model these kinetics are spatially heterogeneous, with endocardial, mid-myocardial and epicardial tissue occupying approximately equal fractions of the transmural distance. In the cuboid, the diffusion coefficient was 0.154 mm2 ms-1 in all directions. The diffusion coefficient in the wedge was set to 0.154 mm2 ms-1 in the fiber axis direction, with a ratio of...

Yin A. and Kelly T. K. (2000) An elastic wedge model for the development of coeval normal and thrust faulting in the Manna Loa-Kilauea rift system in Hawaii. J. Geophys. Res. Solid Earth 105, 25909-25925. 

For a given 0-W component pair the C region wouid become concave toward W whenever the interactions between the amphiphile and the O phase are larger than the interaction of the amphiphile and the W phase or conversely (see Fig. 9). This is essentially equivalent to the so-called orienled wedge model (30,31) but with each amphiphile molecule associated with a certain amount of both O and W molecules, so that the resulting wedge units detennine the bending when they are placed aside in the micellar or microemulsion structure. 

A Method to Measure Fiim Drainage Rates The Coiiapsing Wedge Model... 

As illustrated in Figure 9.18, we see that the trend of the experimental observations is reproduced by this geometrical model, by simply assuming that the solute acts as a wedge in the surfactant film. The main term not taken into account by the wedge model comes from neglecting oil adsorption/desorption in the film induced by the presence of the solute. 

The simple wedge model also explains the observed effect of oil on the solubilization of testosterone propionate (50). In this case, the excess solubilization... 

Figure 9.18. Variation of the reduced average curvature (//) versus the interfacial molar composition X, with C representing the chain length of the surfactant A H)l = H(X 0)) — jH(X = 0)). The dashed line is calculated with the wedge model , experimental points obtained by phase diagram determination and titration in the Winsor III domain , maximum of solubilization obtained in micellar system A, obtained in a Winsor I microemulsion...

At a fundamental level, the effect of the presence of a solute can be evaluated by the wedge model , since volume variation induced by the presence of the solute is known and experimental values for partial molar surfaces can be obtained from scattering experiments. All general intrinsic variables associated with a surfactant layer are profoundly influenced by the presence of solutes, namely bending constants and spontaneous radii of curvature, and hence the corresponding phase limits. 

It should be emphasized that the mechanism of selectivity according to the wedge model involves both the expanded and nonexpanded portions of the mica. LeRoux and Rich [1969] showed that Rb-Sr selectivity of weathered muscovite and biotite first increased and then decreased as the degree of potassium depletion increased. One would expect that the number of wedge zones would also first increase and then decrease as weathering entirely through an interlayer eliminated wedge zones. 

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