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Equilibrium layer

First-order phase transition from a nucleonic matter to the strange quark state with a transition parameter A > 3/2 that occurs in superdense nuclear matter generally gives rise to a toothlike kink on the stable branch of the dependence of stellar mass on central pressure. Based on the extensive set of calculated realistic equations of state of superdense matter, we revealed a new stable branch of superdense configurations. The new branch emerges for some of our models with the transition parameter A > 3/2 and a small quark core (.Mcore 0.004 A- 0.03M ) on the M(PC) curve, with Mmax 0.08M and A 0.82M for different equations of state. Stable equilibrium layered... [Pg.339]

Thus, the equilibrium layer thickness must satisfy... [Pg.201]

Proteins are not very suitable for making fine emulsions in other words, it takes more energy to obtain small droplets than with a small-molecule surfactant. This is primarily due to their large molar mass. It causes the effective y value that they can produce at the O-W interface to be fairly large. Moreover, their molar concentration is small at a given mass concentration, causing the Gibbs elasticity to be relatively small. This means that prevention of recoalescence is less efficient. Proteins are not suitable to make W O emulsions, as follows from Bancroft s rule they are insoluble in oil. The adsorption layer of proteins on the droplets obtained by emulsification is not an equilibrium layer, whereas it is for small-molecule surfactants. [Pg.454]

Dynamic adsorption layers differ from equilibrium layers not only by the existence of an angular dependence but also by the difference in the adsorbed amount averaged over the bubble surface (Sadhal Johnson, 1983). Usually, in foam flotation, the surfactant yield is calculated under the assumption of equilibrium adsorption at the surface of buoyant bubbles. The theory of dynamic adsorption layers lead to substantial changes in the notion of surfactant flotation. Thus, the mechanism of transport at the bubble-solution interface has a substantial effect on the transport process at the surfactant solution-foam boundary. [Pg.270]

Calculations show that the model of a non-equilibrium surface layer is an alternative to kinetic-controlled adsorption models. On the basis of the purely diffusion-controlled adsorption mechanism the proper consideration of a non-equilibrium diffusion layer leads to a satisfactory agreement between theory and experimental data for various studied systems, systematically demonstrated for the short-chain alcohols [132], The non-equilibrium model is applicable in the concentration range from 10 to 10 mol/cm at different values of the Langmuir constant at- For l < 10 mol/cm a consideration of non-equilibrium layer effects is not necessary. For ai > 10 mol/cm and large surfactant concentration the Ay values calculated from the proposed theory do not compensate the discrepancy to the experimental data so that other mechanisms have to be taken into account. An empirical formula also proposed in [132] for the estimation of the non-equilibrium surface layer thickness leads to a better agreement with experimental data, however this expression restricts the validity of the non-equilibrium surface layer model as alternative to non-diffusional adsorption kinetics. [Pg.324]

Measurements of equilibrium layer thickness were also done on the fibrinogen-glass system (11). The thickness versus solution concentration data showed an overall increase corresponding to the adsorption versus concentration curve. However the thick-... [Pg.492]

The equilibrium layer thickness follows from equating the attractive and repulsive forces (Eqs. 40 and 41). For rather stiff polymers and small layer thickness, S < K < lef[, we obtain... [Pg.301]

Beni and Hackwood [29] although a demonstrable prototype concept was only produced in 2003 by Hayes and Feenstra [30]. The principle is illustrated in Fig. 10a. A dyed oil drop under a transparent aqueous solution is confined within a cell that represents a single pixel in the reflective display the cell is placed atop a white substrate. A hydrophobic layer is coated at the bottom of the cell such that in the absence of an applied potential, the oil forms a thin equilibrium layer covering the entire cell area. Upon application of the electric field, however, the contact angle increases, and the oil film retracts to form a drop in the comer of the cell. The extent to which the drop retracts is thus dependent on the applied voltage. The 250 pm pixels are also believed to be sufficiently small such that an area average is only apparent to the observer the retracted spot... [Pg.989]

An extended brush-like layer is formed for the zwitterionically terminated polystyrene and comparison of force-distance curves before and after oscillatory motion showed that they were not displaced by the lubrication forces. These force-distance curves showed that the two brush-like layers interact at distances of about 2500 A. Above this separation, values of G scale with D in precisely the same manner both in the presence and in the absence of tethered polymer. The slopes of these lines, moreover, gave a viscosity (j/o) that agreed with the bulk viscosity of toluene. For the tethered pol)nner the line through these large separation data has an x axis intercept that corresponds closely to twice the polymer layer s thickness. Hence, in this region the shear plane in the system has shifted by a distance of 2Lh (Lr is hydrod5mamic layer thickness equilibrium layer thickness) and thus equation (3.4.13) becomes... [Pg.118]

With this model for we run into a problem for t - 0, since for Zq 0 would then become infinite. We therefore have to find a more realistic model. The singularities can be avoided by a two layer model composed of an inertial zone Zq < z < z. and an equilibrium layer z > z >z. . [Pg.239]

Simple extensions to cases where liquids A and B are only partially soluble and where solid C is distributed between the equilibrium layers are readily visualized. For example, in the configuration shown in Fig. 2.17, the situation is fundamentally similar to that in Fig. 2.16, except that the... [Pg.19]

Fig. 2.30. Distribution of C between equilibrium layers of a Type 2 system, B-froe basis. Fig. 2.30. Distribution of C between equilibrium layers of a Type 2 system, B-froe basis.
Surface Polymers (per sphere) Invading Polymers (per sphere) Relaxation Time r (hrs) a Equilibrium Layer Thickness h(oo)(nm)... [Pg.76]

EXAMPLE 12J-1. Material Balance for Equilibrium Layers An original mixture weighing 100 kg and containing 30 kg of isopropyl ether (C), 10 kg of acetic acid (.4), and 60 kg water (B) is equilibrated and the equilibrium phases separated. What are the compositions of the two equilibrium phases ... [Pg.711]

As in amorphous polymer systems, it is difficult to achieve equilibrium in these systems. When it is achieved then, as for amorphous copolymers, the equilibrium layer thickness is governed by a balance of thermodynamic driving forces. However, the underlying physics has some differences from the amorphous case. Nonetheless, these structures can still be understood on the basis of a modified NSCFT [62,109]. [Pg.347]

The equilibrium layer thickness, d, is obtained by minimizing the free energy, Eq. (88). All of the contributions to AF depend on d, but the dependence of both/ioc and/int is very weak. Hence, the equilibrium thickness is determined primarily by a balance between/cr and/am-... [Pg.350]

IJ>s h) in Fig. 6 and its negative maximum or zero, there are two stable solutions that correspond to equilibrium layers of different finite thickness. A thin film can coexist with the bulk state (a film of macroscopic thickness) when the maximum of this curve is positive. [Pg.12]

Although the Navier-Stokes equations are not valid in the Knudsen layer, due to a nonlinear stress/strain-rate behavior in this small layer [4], their use with appropriate boundary velocity slip and temperature jump conditions proved to be accurate for predicting mass flow rates [5] ( methods for flow rate measurements) and velocity profiles out of the Knudsen layer. Classically, the real flow is not simulated within the JCnudsen layer, but the influence of the Knudsen layer on the flow outside this non-equilibrium layer is taken into account, replacing the no-slip condition at the wall with a slip-flow condition. For that purpose, a fictitious slip velocity MsUp is introduced (Fig. 2). Real slip at the wall, gas — wall. is due to the fact that gas molecules very close to the wall have actually a mean... [Pg.1717]

Figure 8.21 Steps in biofilm formation. Formation is initiated when small organic molecules become attached to an inert surface (1) and microbiological cells are adsorbed onto the resulting layer (2). The cells send out hair like exopolymers to feed on organic matter (3), adding to the coating (4). Flowing water detaches some of the formation (5), producing an equilibrium layer. Figure 8.21 Steps in biofilm formation. Formation is initiated when small organic molecules become attached to an inert surface (1) and microbiological cells are adsorbed onto the resulting layer (2). The cells send out hair like exopolymers to feed on organic matter (3), adding to the coating (4). Flowing water detaches some of the formation (5), producing an equilibrium layer.

See other pages where Equilibrium layer is mentioned: [Pg.79]    [Pg.331]    [Pg.86]    [Pg.501]    [Pg.214]    [Pg.113]    [Pg.201]    [Pg.206]    [Pg.93]    [Pg.503]    [Pg.18]    [Pg.254]    [Pg.21]    [Pg.21]    [Pg.70]    [Pg.86]    [Pg.93]    [Pg.93]    [Pg.94]    [Pg.2005]    [Pg.219]    [Pg.714]    [Pg.26]    [Pg.76]    [Pg.612]    [Pg.66]    [Pg.590]    [Pg.4]   
See also in sourсe #XX -- [ Pg.233 ]




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Effect of a non-equilibrium adsorption layers

Electrical double layer at equilibrium

Equilibrium catalyst layers

Equilibrium double layer

Equilibrium electrode potentials electrical double layer

Equilibrium grafted-layer thickness

Equilibrium layer spacing

Equilibrium surface layer

Intrinsic equilibrium constants triple layer model

Non-equilibrium distribution of adsorbing ions along the diffuse layer

Non-equilibrium surface forces caused by dynamic adsorption layers

The Electrical Double Layer Is an Example of Electrostatic Equilibrium

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