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Exact derivative

It maybe noted that the above system of equations is very general and encompasses both the usual equations given for gas absorption and distillafion as well as situations with any degree of counterdiffusion. The exact derivations maybe found elsewhere (43). [Pg.28]

Scherrer equation to estimate the size of organized regions Imperfections in the crystal, such as particle size, strains, faults, etc, affect the X-ray diffraction pattern. The effect of particle size on the diffraction pattern is one of the simplest cases and the first treatment of particle size broadening was made by Scherrer in 1918 [16]. A more exact derivation by Warren showed that. [Pg.348]

The exact derivative is approximated by a finite-difference derivative to yield... [Pg.398]

An exact derivation that takes into account the variation of the Fermi level with temperature gives basically the same result ... [Pg.253]

As to the automatic generation of exact derivatives in existing modular-based process simulator codes directly from the code itself, refer to Griewank and Corliss (1991) or Bischof et al. (1992). [Pg.546]

The second advantage of a T-first approach is that it builds on what students think are familiar concepts, such as work, energy, and temperature. That these are in fact rather sophisticated concepts can be allowed to dawn on them. At least, when they begin the course they are in the seemingly familiar world of macroscopic events and concepts, and there is an easy (but perhaps false) familiarity with the basic ideas of the subject. Moreover, even the mathematics is relatively familiar, with only the concepts of partial and exact derivatives central to its exposition. [Pg.46]

R.I. Jennrich and P.B. Right, Fitting systems of linear differential equations using computer generated exact derivatives, Technometrics,... [Pg.318]

Clearly, the MFI description does not capture all possible complicated mechanisms of ET activation in condensed phases. The general question that arises in this connection is whether we are able to formulate an extension of the mathematical MH framework that would (1) exactly derive from the system Hamiltonian, (2) comply with the fundamental linear constraint in Eq. [24], (3) give nonparabolic free energy surfaces and more flexibility to include nonlinear electronic or solvation effects, and (4) provide an unambiguous connection between the model parameters and spectroscopic observables. In the next section, we present the bilinear coupling model (Q model), which satisfies the above requirements and provides a generalization of the MH model. [Pg.168]

It shoiild be noted that this is the exact derivation of equation (3). These models are usually referred to quasi-linear models and display qualitatively correct predictions of typical phenomena of elongational flows such as the occurrence of the strain-hardening effect in transient extension. Nevertheless the predicted elongational viscosity is never boimded in the long time range and a steady state value can only be expected for small elongation rates. Moreover, the shear behaviour remains unrealistic as compared to the experiment, especially because of constant predicted viscosity and first normal... [Pg.147]

A solvable model which we have not investigated is the one of coupled harmonic oscillators. This was introduced by Ford and his collaborators [Ford 1965] and also by Ref. [Ullersma 1966], This model provides a formally exact derivation of the Master Equation. Many features of irreversible evolution can be investigated exactly within this model for example see Ref. [Haake 1985 Strunz 2003]. The result is also equivalent with the approaches in Refs. [Cal-deira 1983 Unruh 1989],... [Pg.280]

However, to the author s knowledge, this model has not been applied for the prediction of multiphase reactors mostly due to the complexity of the suggested closure relations. On the other hand, this paper serves as a useful reference as the exact derivation of the k — e model equations are given and discussed. Parts of this modeling work have been adopted in many papers. [Pg.553]

Note that only the same coefficient derivatives are required as in the SCF second derivative case in particular, the exact derivatives of the canonical molecular orbitals are not required. The formulation of Gaw et al. (1984) does apparently use the latter. As discussed in Section III.C, this may lead to numerical difficulties in the case of degeneracies or quasi-degeneracies. Recently Gaw and Handy (1986) eliminated the canonical orbital derivatives from their program, in agreement with the results above. An extension of the closed-shell third derivative program to open-shell and MCSCF wavefunc-tions would be highly desirable for calculating reaction surfaces. [Pg.269]

For details and an exact derivation of the reader is referred to ref. [13]. The derivation also shows that Z is in series with as shown in Fig. 4.13a. Typically, the Warburg impedance leads to a linear increase of Z with rising Z" and the slope is 45° as also shown in Fig, 4.13a. In this case, Z has been calculated assuming an infinite thickness of the diffusion layer. Any convection of the liquid limits the thickness of the diffusion layer. The latter is limited to a well defined value when a rotating disc electrode is used (see Section 4.2.3). In this case, the impedance spectrum is bent off at low frequencies as shown in Fig. 4.13b. The Z branch i.s only linear at its high frequency end where it shows a slope of 45°. [Pg.72]

In Section II we will give a fairly simple but exact derivation of the equations that govern the behavior of the molecule in frequency and time space. [Pg.134]

First note that apart from the requirement of linear response, Eq. (6) is the result of an exact derivation. As long as our system is represented by the appropriate part of the model of Fig. 1, all experiments in the limit of E(t) - 0 should be represented by it. [Pg.138]

Considering compressible flow through an orifice the following equation gives the mass flow. An exact derivation is available at http //www.combustion-modeling.com... [Pg.80]

The exact derivation utilises the energy levels written as... [Pg.620]

This function is shown in Figure. 2.22. In an exact derivation the Fermi energy in this equation must be substituted by the chemical potential of the electrons. At experimental... [Pg.47]


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See also in sourсe #XX -- [ Pg.160 ]




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