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Boundary Parameters

Boundary impedances refer either to heterocontacts, such as the contacts of the electrode to the electrolyte or contacts between the grains of different phases in composites, or to homocontacts, i.e., grain boundaries. In this chapter, we restrict ourselves to resistive [Pg.77]

A reasonable approximation of the impact of such a boundary in series to the current flow is provided by a parallel R-C circuit (R, C ) in series to the bulk impedance [Pg.78]

(62) can take account of the dielectric response of a boundary (electrode, grain boundary) but would not be sufficient to describe bulk polarization phenomena (appearing at longer times or lower frequencies) induced by strongly selectively blocking electrodes or grain boundaries (see below). The latter effect will be touched upon in the next section. [Pg.78]

The boundary resistance R is dominated either by the space charge resistance in the current direction or the proper charge transfer resistance through the boundary core (Part I, Section VI.6). (Resistance effects due to laterally inhomogeneous contact conditions are discussed in Section III.9). [Pg.78]


The boundary between two neighboring domains is characterized by a set of the k2 and k2 values and ambient conditions at which the inhibitory mechanism possesses the features of two basic mechanisms. These boundary quantities and conditions can be described by respective parametric expressions (Table 14.6). Since boundaries have a finite width, rate constants change continuously between domains. Conventionally, the boundary width is taken such that the ratio of the rate constants of the key reactions changes across the boundary e times, which corresponds to a threefold change in the boundary parameters. [Pg.505]

The final seep of constructing the SIMCA models is to merge the calibration and test s iples for each of the classes and reconstruct new SIMCA models using ail of e data. The rank and boundary parameters determined in Habit 4 are used fer the final models. These models are used to predict the class(cs) of unknown smples. Table 4.24 contains the values for three unknown samples where the empirically determined critical value is 1.6. From the values, the aaclusions are that unknown 1 is not a member of any class in the training ses unknown 2 is a member of class B, and tonknown 3 is a member of both classes A and B. [Pg.85]

This transformation allows for equal distribution in the y-space while concentrating the lines close to the x = L boundary. Parameter a sets the spacing of the lines. This technique is called MOL1D (Method Of Lines in 1 Dimension) and is suitable for solving parabolic and hyperbolic initial boundary value problems in one dimension. [Pg.37]

Morris, D. G. Munoz-Morris, M. A. Relationships between mechanical properties, grain size, and grain boundary parameters in nanomaterials prepared by severe plastic deformation, by electrodeposition and by powder metallurgy methods. J. Metastable Nanocrystal. Mater. 15-16, 585-590 (2003). [Pg.235]

We will see that in the steady state of the blocking cells, we can extract partial conductivities, and from the transients chemical diffusion coefficients (and/or interfacial rate constants). Cell 7 combines electronic with ionic electrodes here a steady state does not occur but the cell can be used to titrate the sample, i.e., to precisely tune stoichiometry. Cell 1 is an equilibrium cell which allows the determination of total conductivity, dielectric constant or boundary parameters as a function of state parameters. In contrast to cell 1, cell 2 exhibits a chemical gradient, and can be used to e.g., derive partial conductivities. If these oxygen potentials are made of phase mixtures212 (e.g., AO, A or AB03, B203, A) and if MO is a solid electrolyte, thermodynamic formation data can be extracted for the electrode phases. [Pg.75]

Clearly, pharmacodynamic acceptability boundaries are diffuse, but with consideration of the target, a set of useful boundary parameters may be set within which molecules may be considered drug like . [Pg.29]

The essence of the approach to obtaining the boundary parameters is as follows. One chooses a shear rate y and a zero shear position qy. This sets the velocity profile vl qy). Let us assume that we would like to characterize the hydrodynamic boundary parameters (HBP) for the lower wall. After reaching steady state (which is monitored by the generation of the linear velocity profile), the total force from the lower wall, on all the particles is calculated and averaged over 100 ps. Since we have only one equation, Eq. [213] from LRT, with two unknown parameters, two simulations with differing must be... [Pg.371]

The probabilities of breaking an A-A bond being usually different from the probability of breaking an A-B bond, the yield of monomer is different between the homopolymer and the copolymer (see also rel, 2.3.27 and 2.3.28). A boundary parameter pA has been introduced to characterize this difference [9] and is defined by the expression ... [Pg.162]

Table 2 Boundary parameters of extruders and combined de-airing extrusion units used in structural clay industry comparing the levels in 1960 and 2005... Table 2 Boundary parameters of extruders and combined de-airing extrusion units used in structural clay industry comparing the levels in 1960 and 2005...
This expected linearity is usually experimentally confirmed. A theoretical prediction of the size of the linear rate constant in Eq. (6) for a given temperature and composition of medium and material is possible, when thermodynamic data are available to calculate the reaction, and boundary parameters such as the geometry of the sample, viscosity, stream velocity, Schmidt and Reynold s numbers are known or can be estimated [16]. [Pg.146]

With regards to the boundary condition, the principle of mirror reflection was used in the symmetry axis and the body surface to model the conditions of zero normal component flow and slip (or no-slip) flow on the surface body. In the upstream of the external boundary, parameters of unperturbed... [Pg.236]

Table 2. Relative boundary parameters of a change region for the roughness function... Table 2. Relative boundary parameters of a change region for the roughness function...

See other pages where Boundary Parameters is mentioned: [Pg.78]    [Pg.77]    [Pg.179]    [Pg.42]    [Pg.79]    [Pg.833]    [Pg.365]    [Pg.370]    [Pg.376]    [Pg.205]    [Pg.77]    [Pg.66]    [Pg.104]    [Pg.252]    [Pg.600]    [Pg.151]    [Pg.176]    [Pg.78]    [Pg.417]    [Pg.254]   


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