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Asymptotic conditions applications

We will carry out our program in two steps. In this section we will derive the two-particle density operator Fn in a three-particle collision approximation for the application in the collision integral of Fl. As compared with Section II.2, the main difference will be the occurrence of bound states and, especially, the generalization of the asymptotic condition, which now has to account for bound states too. For the purpose of the application in the kinetic equation of the atoms (bound states) we need an approximation of the next-higher-order density matrix, that is, F 23 This quantity will be determined under inclusion of certain four-particle interaction. [Pg.205]

In the case of a single mode in the selected band, it has been possible to derive closed-form analytical expressions for the posterior covariance matrix under asymptotic conditions, namely, small damping and long data duration, which are typically met in applications. The expressions are collectively referred as uncertainty laws (Au 2014a, b). They provide insights on the scientific nature of the ambient modal identification problem and its fundamental limits on identification uncertainty. The uncertainty laws can also be used for drafting specifications for ambient vibration tests. [Pg.223]

In the more general problem in which V (r) 0, the previous boundary condition is not applicable. Thus, B((a) 0 and the asymptotic solution for lttge values of r is given by [Eq. (5-148)]... [Pg.289]

An application of the variational principle to an unbounded from below Dirac-Coulomb eigenvalue problem, requires imposing upon the trial function certain conditions. Among these the most important are the symmetry properties, the asymptotic behaviour and the relations between the large and the small components of the wavefunction related to the so called kinetic balance [1,2,3]. In practical calculations an exact fulfilment of these conditions may be difficult or even impossible. Therefore a number of minimax principles [4-7] have been formulated in order to allow for some less restricted choice of the trial functions. There exist in the literature many either purely intuitive or derived from computational experience, rules which are commonly used as a guidance in generating basis sets for variational relativistic calculations. [Pg.177]

Petersen [12] points out that this criterion is invalid for more complex chemical reactions whose rate is retarded by products. In such cases, the observed kinetic rate expression should be substituted into the material balance equation for the particular geometry of particle concerned. An asymptotic solution to the material balance equation then gives the correct form of the effectiveness factor. The results indicate that the inequality (23) is applicable only at high partial pressures of product. For low partial pressures of product (often the condition in an experimental differential tubular reactor), the criterion will depend on the magnitude of the constants in the kinetic rate equation. [Pg.164]

It might seem at first glance that arriving at the dipole moment p of an ellipsoidal particle via the asymptotic form of the potential < p is a needlessly complicated procedure and that p is simply t>P, where v is the particle volume. However, this correspondence breaks down for a void, in which P, = 0, but which nonetheless has a nonzero dipole moment. Because the medium is, in general, polarizable, uP, is not equal to p even for a material particle except when it is in free space. In many applications of light scattering and absorption by small particles—in planetary atmospheres and interstellar space, for example—this condition is indeed satisfied. Laboratory experiments, however, are frequently carried out with particles suspended in some kind of medium such as water. It is for this reason that we have taken some care to ensure that the expressions for the polarizability of an ellipsoidal particle are completely general. [Pg.148]

Application/compendial requirements plus multipoint dissolution profiles in additional buffer stage testing (e.g., USP buffer media at pH 4.5-7.5) under standard and increased agitation conditions until >80% of drug released or an asymptote is reached Apply some statistical test (f2 test) for comparing dissolution profiles No biostudy... [Pg.77]

Transfer coefficients in catalytic monolith for automotive applications typically exhibit a maximum at the channel inlet and then decrease relatively fast (within the length of several millimeters) to the limit values for fully developed concentration and temperature profiles in laminar flow. Proper heat and mass transfer coefficients are important for correct prediction of cold-start behavior and catalyst light-off. The basic issue is to obtain accurate asymptotic Nu and Sh numbers for particular shape of the channel and washcoat layer (Hayes et al., 2004 Ramanathan et al., 2003). Even if different correlations provide different kc and profiles at the inlet region of the monolith, these differences usually have minor influence on the computed outlet values of concentrations and temperature under typical operating conditions. [Pg.116]

Thus, the three-layer scheme (13) of accuracy 0(h2 + r2) possesses the proper asymptotics as —> oo under the unique restriction t6 < 1/2, which is not burdensome. Comparison of the final results with the two-layer scheme (4) reveals some formal advantage of the three-layer scheme over the symmetric two-layer scheme with a = which is conditionally asymptotically stable if we imposed the extra constraint t < t0 — 1 /y/6 A, r0 = r0(fi), in addition to the usual one t8 < 1. However, this restriction is sufficiently weak in real-life situations and, therefore, it is meaningless to speak about any practical advantage of the three-layer scheme. For this reason the two-layer scheme is quite applicable and more efficient in practical implementations. [Pg.340]

Delayed release product In appli-cation/compendial release requirements plus dissolution tests in 0.1 N HC1 for 2 hr (acid stage) followed by testing in USP buffer media (pH 4.5-7.5) under application/compendia test conditions and two additional agitation speeds. Application/compen-dial method may be either apparatus 1 or apparatus 2.1 Adequate sampling should be performed (15, 30, 45, 60, and 120 min until either 80% of drug is released or asymptote is reached). Testing should be performed on changed product and biobatch or marketed product. [Pg.760]


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See also in sourсe #XX -- [ Pg.261 ]

See also in sourсe #XX -- [ Pg.261 ]




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