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Auxiliary functions

Equation (1) is of little practical use unless the fuga-cities can be related to the experimentally accessible quantities X, y, T, and P, where x stands for the composition (expressed in mole fraction) of the liquid phase, y for the composition (also expressed in mole fraction) of the vapor phase, T for the absolute temperature, and P for the total pressure, assumed to be the same for both phases. The desired relationship between fugacities and experimentally accessible quantities is facilitated by two auxiliary functions which are given the symbols (f... [Pg.14]

The following derivatives represent protective groups that contain an auxiliary functionality, which when chemically modified, results in intramolecular, assisted cleavage, thus increasing the rate of cleavage over simple basic hydrolysis. [Pg.111]

Example The auxiliary functions in Figure 51.9 are identified as those work elements performed by the craftsper-son which are part of the job, but which are not apparent after the work is completed. These include such functions as job planning by the craftsman, travel time, obtaining materials, and miscellaneous get-ready and clean-up work. The auxiliary time is affected by the physical facilities involved, such as facility layout, location of shops, degree of material delivery, and so forth. If sufficient studies are taken, the auxiliary work can be related to the direct work and ratios determined for each craft by type of work. [Pg.831]

Since Eqs. (5) and (6) are not restricted to the vapor phase, they can, in principle, be used to calculate fugacities of components in the liquid phase as well. Such calculations can be performed provided we assume the validity of an equation of state for a density range starting at zero density and terminating at the liquid density of interest. That is, if we have a pressure-explicit equation of state which holds for mixtures in both vapor and liquid phases, then we can use Eq. (6) to solve completely the equations of equilibrium without explicitly resorting to the auxiliary-functions activity, standard-state fugacity, and partial molar volume. Such a procedure was discussed many years ago by van der Waals and, more recently, it has been reduced to practice by Benedict and co-workers (B4). [Pg.171]

Example 4.3 represents the simplest possible example of a variable-density CSTR. The reaction is isothermal, first-order, irreversible, and the density is a linear function of reactant concentration. This simplest system is about the most complicated one for which an analytical solution is possible. Realistic variable-density problems, whether in liquid or gas systems, require numerical solutions. These numerical solutions use the method of false transients and involve sets of first-order ODEs with various auxiliary functions. The solution methodology is similar to but simpler than that used for piston flow reactors in Chapter 3. Temperature is known and constant in the reactors described in this chapter. An ODE for temperature wiU be added in Chapter 5. Its addition does not change the basic methodology. [Pg.125]

The mapping (7) introduces the unknown interface shape explicitly into the equation set and fixes the boundary shapes. The shape function h(x,t) is viewed as an auxiliary function determined by an added condition at the melt/crystal interface. The Gibbs-Thomson condition is distinguished as this condition. This approach is similar to methods used for liquid/fluid interface problems that include interfacial tension (30) and preserves the inherent accuracy of the finite element approximation to the field equation (27)... [Pg.308]

It is clear that Equation (1.39) defines the potential [/ up to a constant, since grad C = 0, that is, an infinite number of potentials describe the same field g. For this reason, it is appropriate to consider the potential as an auxiliary function introduced with mainly one purpose, namely, to simplify the analysis of the more complicated field g. Our next step is obvious we have to find an equation,... [Pg.18]

The Auxiliary Functions Menu Is used less frequently than the other two menus. The first function creates a disc file that steers the online data reduction process in a manner chosen by the user. Seme adaptability is necessary here because procedures for picking baselines, etc. will vary from one group of specimens to another. [Pg.133]

The data reduction program can be driven interactively from the console terminal or in batch mode from a command file created by the customizing function on the auxiliary functions menu. [Pg.135]

Determination of the column calibration is greatly facilitated by special computer programs (on the Auxiliary Functions Menu). [Pg.137]

The selections in the "Auxiliary Functions Menu" do not produce archlvable data, but are used as aids in setting up a specimen and diagnosing problems with the diffractometer. [Pg.143]

Hong and Noolandi first transform the time-dependent density function to an auxiliary function h by writing... [Pg.236]

The 670 titroprocessor can also be used to solve complex analytical tasks. In addition to various auxiliary functions which can be freely programmed, up to four different titrations can be performed on a single sample. [Pg.40]

Finally, and more profoundly, not all properties require explicit knowledge of the functional form of the rate equations. In particular, many network properties, such as control coefficients or the Jacobian matrix, only depend on the elasticities. As all rate equations discussed above yield, by definition, the assigned elasticities, a discussion which functional form is a better approximation is not necessary. In Section VIII we propose to use (variants of) the elasticities as bona fide parameters, without going the loop way via explicit auxiliary functions. [Pg.185]

Figure 5.10 (a) The ligand (b) the catalytically catalyst constrained within a mesopore, active metal center bound inside the pores of indicating the space constraint and the mesoporous MCM-41, now with an extra diamine auxiliary functionality . (Modified nitrogen, indicating the anchoring point on from Thomas et al. [58].) the tether (c) schematic diagram of the chiral... [Pg.183]

As indicated in Fig. 7, the next step after either an explicit or an implicit energy density functional orbit optimization procedure. For this purpose, one introduces the auxiliary functional Q[p(r) made up of the energy functional [p(r) 9 ]. plus the auxiliary conditions which must be imposed on the variational magnitudes. Notice that there are many ways of carrying out this variation, but that - in general - one obtains Euler-Lagrange equations by setting W[p(r) = 0. [Pg.206]

Associate the Lagrange multiplier ji (chemical potential) with the normalization condition in Eq. (6), the set of Hermitian-Lagrange multipliers X[ with orthonormality constraints in Eq. (4), and define the auxiliary functional Q, by the formula... [Pg.401]

In Eq. (20), iqis the auxiliary function for the Fresnel integrals [44]. In practice, it is usual to choose empirical scavenging functions F(S) that have analytical inverse Laplace transforms. [Pg.345]

The nonlogarithmic contributions of order a Zay were never calculated directly. These corrections together with contributions in (3.60), (3.97) and the corrections of higher orders in Za are usually parametrized with the help of an auxiliary function GsB Za)... [Pg.72]

There are no obstacles to exact numerical calculation of the Uehling potential contribution to the energy shift without expansion over Za and such calculations have been performed with high accuracy (see [65, 117] and references therein). The results of these calculations may be conveniently presented with the help of an auxiliary function Gu,7 Za) defined by the relationship... [Pg.75]

The linear viscoelastic properties are often expressed in terms of an auxiliary function, the relaxation time distribution, H(x) H(x)dlnx is the portion of the initial modulus contributed by processes with relaxation times in the range lnt, InT + dlnt ... [Pg.24]

In chapter I it was shown how the handling of moments and cumulants was facilitated by the use of a moment generating function. A similar tool will now be introduced with respect to the / . Instead of the auxiliary variable k we now need an auxiliary function, or test function v(t and instead of a generating function we have therefore a functional, i.e., a quantity depending on all the values that v takes for — oo < t < oo (indicated by [v]). The generating functional for the / is... [Pg.37]


See other pages where Auxiliary functions is mentioned: [Pg.268]    [Pg.150]    [Pg.234]    [Pg.120]    [Pg.133]    [Pg.90]    [Pg.98]    [Pg.261]    [Pg.355]    [Pg.275]    [Pg.167]    [Pg.17]    [Pg.206]    [Pg.208]    [Pg.221]    [Pg.221]    [Pg.793]    [Pg.137]    [Pg.4]    [Pg.225]    [Pg.10]    [Pg.37]    [Pg.117]    [Pg.118]    [Pg.144]    [Pg.144]   
See also in sourсe #XX -- [ Pg.18 ]

See also in sourсe #XX -- [ Pg.369 ]




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Auxiliary Detergent Functions

Auxiliary electrodes function

Auxiliary wave function

Hermite-Gaussian auxiliary functions

Pure auxiliary functions

Reactor auxiliary systems function

Real auxiliary functions

Structure auxiliary functions

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