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Index limiting cases

For different acceptor particle adsorption isotherms expressions (1.85) - (1.89) provide various dependencies of equilibrium values of <7s for a partial pressure P (ranging from power indexes up to exponential). Thus, in case when the logarithmic isotherm Nt InP is valid the expression (1.85 ) leads to dependence <75 P" often observed in experiments [20, 83, 155]. In case of the Freundlich isotherm we arrive to the same type of dependence of - P" observed in the limit case described by expression (1.87). [Pg.65]

All the phenomena described above are absent in a 2D-junction when the effects of transverse mode quantization are neglected [7]. We have considered the limiting case of a single (transverse) channel because this is the case when the effects induced by a dispersion asymmetry in the electron spectrum are most pronounced. The anomalous supercurrent Eq. (7) is a sign alternating function of the transverse channel index since for neighboring channels the spin projections of chiral states are opposite [4]. Besides, the absolute value of the dispersion asymmetry parameter decreases with transverse-channel number j. So, for a multichannel junction the effects related to a dispersion asymmetry phenomenon will be strongly suppressed and they completely disappear in the pure 2D case. [Pg.226]

Figure 10.16. Illustration of the definition of intermittency index for three limiting cases (after Brereton and Grace, 1993a) (a) Ideal cluster flow (b) Core-annular flow (c) Uniform dispersed flow. Figure 10.16. Illustration of the definition of intermittency index for three limiting cases (after Brereton and Grace, 1993a) (a) Ideal cluster flow (b) Core-annular flow (c) Uniform dispersed flow.
This relations are valid for small mode numbers, in any case, a -C M/Me. The index 5 in the above formula can be estimated theoretically (5 > 2) and empirically according to the measurements of the characteristics of viscoelasticity (5 2.4). It remains to be a dream to get a unified formula for relaxation times from the system of dynamic equations (3.37). One can expect that the all discussed relaxation branches will emerge as different limiting cases from one expression for general conformation branch. [Pg.78]

Here T is the temperature, p is the pressure, a is the surface tension, A is the surface area, V is the volume, 5 is the entropy density, Pi are the particle densities, and pi the chemical potentials of the different components, R is the radius of the critical cluster referred to the surface of tension, the index a specfies the parameters of the cluster while p refers to the ambient phase. The equilibirum conditions coincide with Gibbs expressions for phase coexistence at planar interfaces (R oo) or when, as required in Gibbs classical approach, the surface tension is considered as a function of only one of the sets of intensive variables of the coexisting phases, either of those of the ambient or of those of the cluster phase. In such limiting cases, Gibbs equilibrium conditions... [Pg.392]

By analogy with the discrete case, we may assign to E(T, P, N v) the meaning of a partial molar quantity of the appropriate v -species. The functional derivative in (3.136) is viewed here as a limiting case of (3.133) when the index z becomes... [Pg.107]

The study of the osmotic equilibrium between a polymer solution in two solvents and a mixture of these two solvents is quite instructive. In particular, we shall describe a limiting case in which we shall be able to define a coefficient characterizing the action of the polymers on the solvent distribution. First, let us attribute the index 0 to the main solvent, the index 1 to the second solvent, and the index 2 to the polymer. We have / = 1, m = 2. The numbers of molecules are N s, (jit = 0,1,2) in cell I of Fig. 5.1 and (,r/ = 0,1) in cell II. The chemical potentials of the solvents are, respectively,... [Pg.150]

This characteristic current is the principal index of an assembly s capacity for cross-reaction. As in the previous limiting cases, the expression for the current is... [Pg.616]

Since the usual transmission experiment directly monitors the electrolytic product, it offers many of the diagnostic features of reversal chronoamperometry or reversal chrono-coulometry. In effect, is a continuous index of the total amount of the monitored species still remaining in solution at the time of observation. Equation 17.1.2 describes the limiting case in which the product is completely stable. If homogeneous chemistry tends to deplete the concentration of R, different absorbance-time relations will be seen. They can be predicted (e.g., by digital simulations see Appendix B), and curves for many mechanistic cases have been reported (17). [Pg.683]

The discussion to this point has centered on the limiting case D = 0. In many instances this limit may not be realistic for macromolecules. With D > 0, diffusion will cause a broadening of the shock interfaces, which will increase with time, as sketched in Fig. 5.5.4. Also shown there is the concentration gradient dp dr, which is what is commonly measured in an ultracentrifuge with a schlieren optical system. Actually, what is measured with a schlieren system is the gradient of refractive index, which can then be converted to dptdr when the solution is binary. [Pg.178]

Figure 11. The absorption curves calculated from the Mie theory for silver azide containing one part per million by volume of metallic silver for the limiting case in which the particles are much smaller than the wavelength of light. Curve A has been calculated for an index of refraction of AgNa of 1.82 and curve B for a value of 2.20 (after McLaren [91 ]). Figure 11. The absorption curves calculated from the Mie theory for silver azide containing one part per million by volume of metallic silver for the limiting case in which the particles are much smaller than the wavelength of light. Curve A has been calculated for an index of refraction of AgNa of 1.82 and curve B for a value of 2.20 (after McLaren [91 ]).
When both refractive index and the particle size are considered. Van der Hulst [60], suggests a more useful parameter, P(= 2jrd(m — 1)/A.), for discerning the limiting cases according to ... [Pg.624]

In the two limiting cases of small 0 and large 0 the index of a steady state is always -h 1 and the steady state is unique. The uniqueness property for small 0 is a standard property of nonlinear equations of the type of Eq. (1.9.1). The uniqueness for large 0, however, is a rather remarkable characteristic of chemical reaction systems. We shall consider first the case of small 0 and define quantities... [Pg.34]

In general, the dielectric constant associated with a varying field is a complex number, but the imaginary part vanishes in two limiting cases for zero frequency and infinite frequency. The high-frequency dielectric constant e o is to be associated only with the displacements of the electrons from their equilibrium positions, and should satisfy the Maxwell relation Sea = where n is the refractive index. In addition to the electronic displacements, the static dielectric constant sq contains contributions from the atomic polarization and, in case of polar media, the orientation of the molecules. [Pg.2555]

It should be noted that in many applications medium 1 is air or a nonabsorbing crystal, i.e. /Cj = 0. It follows from Equation [12] that the reflectance increases with increasing absorption index of medium 2 (/C2). In the limiting case of /C2 one obtains p —> 1, i.e. a perfect mirror. Expressions for the more complicated case of oblique incidence to absorbing media have been derived (see Further reading). [Pg.64]

Two further examples of type I ternary systems are shown in Figure 19 which presents calculated and observed selectivities. For successful extraction, selectivity is often a more important index than the distribution coefficient. Calculations are shown for the case where binary data alone are used and where binary data are used together with a single ternary tie line. It is evident that calculated selectivities are substantially improved by including limited ternary tie-line data in data reduction. [Pg.71]


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See also in sourсe #XX -- [ Pg.171 ]




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