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Perturbation solutions

Before elosing this ehapter, it is important to emphasize the eontext in whieh the transition rate expressions obtained here are most eommonly used. The perturbative approaeh used in the above development gives rise to various eontributions to the overall rate eoeffieient for transitions from an initial state i to a final state f, these eontributions inelude the eleetrie dipole, magnetie dipole, and eleetrie quadrupole first order terms as well eontributions arising from seeond (and higher) order terms in the perturbation solution. [Pg.389]

Since xi0 is the known solution and xt is the perturbed solution, an important case arises when <( ) - 0 for t - oo. In such a case the stability is asymptotic. [Pg.344]

Peculiar particle velocity, 19 Pendulum problem, 382 Periodicity conditions, 377 Perturbed solution, 344 Pessimism-optimism rule, 316 Petermann, A., 723 Peterson, W., 212 Phase plane, 323 "Phase portrait, 336 Phase space, 13 Photons, 547... [Pg.780]

Regular Perturbation Solution. To effect an analytical expression for the bubble-flow resistance, we consider fast sorption kinetics or equivalently, small deviations from equilibrium surfactant coverage making 0 large. Hence, a regular perturbation expansion is performed in 1/0 about the constant-tension case. The resulting equations for and rf are to zero and first order in 1/0 (21) ... [Pg.489]

The research was greatly facilitated by two important elements. The (formal, perturbative) solution of the Liouville equation is greatly simplified by a Fourier representation (see Appendix). The latter allows one to easily identify the various types of statistical correlations between the particles. The traditional dynamics thus becomes a dynamics of correlations. The latter is completed by... [Pg.16]

Perturbation solutions for two special cases, namely, for n = 1 and n = 2, have been presented by Meadley and Rahman [47], Results based on Eq. (162) and the exact values computed from the perturbation expansion are shown in Tables VIII and IX (for n = 1 and 2, respectively). The agreement is again within 5 to 10%. The expressions of Meadley and Rahman are not accurate for large values of the ratio Da X/Gr /2. However, Eq. (162) can be used without any such restriction. [Pg.46]

The perturbation solution of Meadley and Rahman is not accurate for larger values of X. [Pg.46]

Let us begin by analyzing linear stability of solution (6.3.16) and showing that at some value of parameter I a Hopf bifurcation is indeed occurring. According to the common scheme, we look for a perturbed solution of the form... [Pg.224]

The problem is to have a perturbation solution to the Schrodinger equation with the restriction that the wavefunction shall be antisymmetric to exchange of the electrons between the interacting systems. The simple product functions (in 34) do not satisfy this restriction individually and if we define a set of antisymmetrized products... [Pg.130]

Difference spectra are usually recorded by placing the unperturbed spectrum in the reference light beam of a spectrophotometer and the perturbed solution in the sample beam in carefully matched cuvettes. However, the spectrum shown in Fig. 23-11B was obtained by recording the two spectra independently and subtracting them with the aid of a computer. The same data have been treated in another way by fitting two log normal curves (p. 1283) to the absorption bands and plotting the differences between the mathematically... [Pg.1285]

Parallel-Plate, Nonisothermal Newtonian Drag Flow with Temperature-depen-dent Viscosity (a) Review the approximate linear perturbation solution given in Example 1.2-2 in R. B. Bird, R. C. Armstrong, and O. Hassager, Dynamics of Polymeric Fluids, Vol. 1, Wiley, New York, 1977. (b) Review an exact analytical solution in B. Martin, Int. J. Non-Newtonian Mech., 2, 285-301 (1967). [Pg.232]

Galili and Takserman-Krozer (20) have proposed a simple criterion that signifies when nonisothermal effects must be taken into account. The criterion is based on a perturbation solution of the coupled heat transfer and pressure flow isothermal wall problem of an incompressible Newtonian fluid. [Pg.689]

It should be noted that in the region of very strong interactions, for R - 0, the perturbation solution is still possible (e.g., ref. S) in this case, the unperturbed system will be the united atom. [Pg.270]

We consider spherical particles, and, without loss of generality, the fixed charge in the membrane is assumed to be negative. For simplicity, we assume that the distribution of fixed charge is uniform. The variation of the electrical potential is governed by Eq. (1) with m = 2, and the boundary conditions described by Eqs. (2)-(5). We use the approximate perturbation solution expressed by Eqs. (37) and (38)-(40). Suppose that the membrane is thick, and i Don and [/d are related by Eq. (48). [Pg.318]

Because of the low success rate for the commercialization of new processes, we will continue to develop new processes by proceeding through a hierarchy of designs, and therefore we will still need shortcut models. To decide whether simple models are applicable in a particular situation, we can develop a perturbation solution around a complex model, so that the simple model is the generating solution. With this approach, we can establish an error criterion that will indicate the validity of the simple model. [Pg.539]

A. Rockenbauer and P. Simon, Perturbation solution of the spin Hamiltonian of low symmetry using the projector technique. Mol. Phys., 1974, 28(5), 1113-1126. [Pg.34]

Several graphical curve-fitting techniques have been developed (see Padday [53] for details) that can be used in conjunction with the numerical integration of the Laplace equation by Bashforth and Adams (and by subsequent workers) to determine d and to obtain y v. Smolders [54,55] used a number of coordinate points of the profile of the drop for curve fitting. If the surface tension of the liquid is known and if 0 > 90, a perturbation solution of the Laplace equation derived by Ehrlich [56] can be used to determine the contact angle, provided the drop is not far from spherical. Input data are the maximum radius of the drop and the radius at the plane of contact of the drop with the solid surface. The accuracy of this calculation does not depend critically on the accuracy of the interfacial tension. [Pg.51]

A numerical solution to Eqs. (4-91) through (4-93) is given by Mhaskar.26 The approximate Galerkin and perturbation solutions to these equations for the cocurrent-flow case are recently given by Szeri et al.36 The method of Hlavacek and Hofmann16 outlined for the slow reaction can also be used for this case in a similar way. In many practical cases, Pec is taken to be infinity (i.e the gas phase is assumed to be in plug flow). [Pg.139]

This chapter introduces the quantum mechanics required for the analyses in this text. The state of an electron is represented by a wave funetion ji. Kach observable is represented by an operator O. Quantum theory asserts that the average of many measurements of an observable on electrons in a certain state is given in terms of these by ji 0 d r. The quantization of energy follows, as does the determination of states from a Hamiltonian matrix and the perturbative solution. The Pauli principle and the time-dependence of the state are given as separate assertions. [Pg.2]

In what follows, we seek a perturbation solution that is correct to the first order ... [Pg.44]

Transformation of the infinite domain. There are several ways of dealing with an infinite domain. Guertin et al. (21) chose perturbation solutions of the model as basis functions. [Pg.292]

Perturbation Solution for Le = 1. The simplest case of Le = POjj/Pej = 1 is analyzed here. This assumption yields the adiabatic invariant, B(l-c) = 0-l which can be used to further simplify Eqns. (l)-(5) to... [Pg.309]


See other pages where Perturbation solutions is mentioned: [Pg.377]    [Pg.344]    [Pg.3]    [Pg.21]    [Pg.40]    [Pg.269]    [Pg.220]    [Pg.36]    [Pg.82]    [Pg.418]    [Pg.77]    [Pg.158]    [Pg.232]    [Pg.42]    [Pg.270]    [Pg.167]    [Pg.392]    [Pg.176]    [Pg.149]    [Pg.138]    [Pg.26]    [Pg.23]    [Pg.23]   
See also in sourсe #XX -- [ Pg.46 ]




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