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Coefficient function

Studies of the reaction between various substituted benzenes and nitric acid, which can take place in a number of different acid systems, have been reported in an extensive series of papers by the Marziano group, using correlations with the Me activity coefficient function. This reaction is a two-stage process,... [Pg.40]

In practice this test could be performed numerically without much difficulty due to the identical structure of all the corrections (transition from n to n+1 amounts to replacing Un-i by Un in the expressions for P(x, e), R(x, s) that appear in the integrals in (3.3.42)). Of course, for a conventional asymptotic power expansion there is no need to compare the successive terms as long as the coefficient functions remain bounded. [Pg.95]

Here c(x, t)dx is the concentration of material with index in the slice (x, x + dx) whose rate constant is k(x) K(x, z) describes the interaction of the species. The authors obtain some striking results for uniform systems, as they call those for which K is independent of x (Astarita and Ocone, 1988 Astarita, 1989). Their second-order reaction would imply that each slice reacted with every other, K being a stoichiometric coefficient function. Only if K = S(z -x) would we have a continuum of independent parallel second-order reactions. In spite of the physical objections, the mathematical challenge of setting this up properly remains. Ho and Aris (1987) have shown how not to do it. Astarita and Ocone have shown how to do something a little different and probably more sensible physically. We shall see that it can be done quite generally by having a double-indexed mixture with parallel first-order reactions. The first-order kinetics ensures the individuality of the reactions and the distribution... [Pg.190]

Here the DE system matrix A(x) is a last row companion matrix whose entries in the last row may depend on x. More specifically, most of A s entries are zero, except for ones in its upper co-diagonal and for the negative coefficient functions—1, —ai(x),. .., — a i(x)... [Pg.35]

At the far left is the reed mouthpiece controlled by mouth pressure pm. Another control is embouchure, changed in general by modifying the reflection-coefficient function p h ), where h = /2 - pi. A simple choice of embouchure control... [Pg.529]

The cone-plate rheometer. The cone-plate rheometer is often used when measuring the viscosity and the primary and secondary normal stress coefficient functions as a function of shear rate and temperature. The geometry of a cone-plate rheometer is shown in Fig. 2.47. Since the angle Oo is very small, typically < 5°, the shear rate can be considered constant throughout the material confined within the cone and plate. Although it is also possible to determine the secondary stress coefficient function from the normal stress distribution across the plate, it is very difficult to get accurate data. [Pg.87]

If the normal stress coefficient functions Mr and T2 are ignored, the CEF equation reduces to the GNF equation... [Pg.102]

The coupled Schrodinger equations can be projected onto the fa fa subspace by Feshbach partitioning, giving an equation for the coefficient function Xd(q) in the component faxdiq) of the total wave function. The effective Hamiltonian in this equation is tn + Vd(q) + Vopt, which contains an optical potential that is nonlocal in the <7-space. This operator is defined by its kernel in the fa - fa subspace,... [Pg.165]

The mathematical reconstruction of a property field, F(x,y), from its projection in the 0 direction is the basis of "Computerized Tomography" (1,2). An identical technique can be used to reconstruct a field of linear absorption coefficient functions in a combusting flow field from multiangular path integrated absorption measurements. The linear absorption coefficient is the familiar N.Q. product, where is the concentration of species i and Q. is the absorption cross section of species i at the frequency v. The Bouguer-Lambert-Beer law states that... [Pg.427]

The linear absorption coefficient functions can thus be reconstructed using only projection data. [Pg.428]

These transform functions would then be inserted into Eq. (46) to give the spatial dependence of the mean potential. The reader should be aware that Eqs. (54) and (55) are legitimate coefficient functions in the special case of periodic surface distributions provided that the wavevector is interpreted correctly as a discrete reciprocal lattice vector and the integral in Eq. (46) replaced by a summation (as in Sec. II. A and later sections). [Pg.100]

The governing equations for the coefficient functions gn(t) are obtained by the standard perturbation procedure of substituting expansion (4-227) into the Ray leigh-Plesset equation in the form (4—208) and then equating the sum of all terms at each order in s to zero. The result at 0(1), expressed in dimensional terms, is... [Pg.260]

For each p, the -vector (p) is a linear combination of the four basis vectors (p). With suitable (square-integrable) coefficient functions / (p) we can write... [Pg.43]

It has to be assumed that V x) describes the external field at the space-time point X after a Poincare transformation. This requires a certain behavior of the coefficient functions Vj under Poincare transformations. Let me illustrate this with an example. [Pg.62]

In a similar way, we can give a meaning to the other coefficient functions. [Pg.62]

Let us first consider the general second-order differential equation with quartic polynomial coefficient function ... [Pg.499]

Et Transfer efficiency, over-all F Holdup, fractional volume of dispersed phase in column / Coefficient, function of (Npc)c G Superficial velocity, ft /hr/ft ... [Pg.278]

All above functions for bentonite and water are represented by explicit formulas with an error below 1% in the interval 10<7 <100°C and 0.3 < 5 < 1. The mathematical program Mathcad is used. The coefficient functions K (S,T) and Kj (S,T) for moisture flux are readily obtained. [Pg.336]

Here, and 2 the first and second stress difference coefficient functions, and the derivative of the strain rate is the Jaumann derivative, which is related to a frame of reference that translates and rotates with the local velocity of the fluid (this relationship can be numerically evaluated from the deformation and vorticity tensors). [Pg.445]


See other pages where Coefficient function is mentioned: [Pg.182]    [Pg.44]    [Pg.85]    [Pg.512]    [Pg.535]    [Pg.538]    [Pg.35]    [Pg.102]    [Pg.166]    [Pg.95]    [Pg.100]    [Pg.114]    [Pg.80]    [Pg.342]    [Pg.184]    [Pg.305]    [Pg.135]    [Pg.571]    [Pg.758]    [Pg.158]    [Pg.391]    [Pg.61]    [Pg.62]    [Pg.86]    [Pg.86]    [Pg.476]    [Pg.333]    [Pg.535]    [Pg.171]    [Pg.44]   
See also in sourсe #XX -- [ Pg.2 , Pg.136 ]




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