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Passage Process

To account for the translational factor effects at nonzero impact parameter it would be desirable to find a correction factor such as that given by Eq. (37). There, however, the influence of the translational factors is difficult to verify. The analysis by Pfeiffer and Garcia suggests that expression (37) overestimates the effect of the translational factors at nonzero impact parameter. Hence, in this case the correction (37) may be used as an upper limit estimate. More realistic correction values are expected when the projectile velocity v is replaced by the radial velocity Vr similar to that given by Eq. (39). It should be realized that this replacement implies uncertainties in the treatment of the translational factors. However, these uncertainties lose importance when the correction due to the translational factors is small. [Pg.448]

Following the analysis of Crothers, the transfer probability for the double passage of the transition region is obtained as [Pg.448]

Hartree-Fock calculations are from Briggs/ Model calculations are from Stolter-foht using the SHM matrix elements (18). Analytical results are from Eq. (38). [Pg.448]

The double-passage process has been studied by Schuch et for [Pg.449]

For 6 0 1 a.u. the two sets of theoretical results differ primarily in the frequency of the oscillations. The difference is probably produced by the influence of translational factors. As mentioned above, the single-passage probability W is influenced by translational motion effects through the phase in Eq. (19). In addition, the double passage probability P is affected by the prefactor B(v). The influence of B(v) on the transition probability is not obvious. Here, it should only be noticed that with increasing velocity V the absolute value B(v) decreases so that H,2 is reduced. Then, it follows from Eq. (40) that the oscillation frequency of the double passage probability is reduced. [Pg.449]


The expression of the active transport systems is time-dependent and may vary with nutritional conditions [53, 54]. The culturing conditions, e.g., the passaging process, can dramatically alter the biological characteristics and transport properties of Caco-2 cell monolayers [55-58]. [Pg.96]

FIG. 7 Flow diagrams of the different operating modes for an ED unit (A) batch process (B) continuous single-passage process and (C) feed-and-bleed process. [Pg.285]

The hot pad dry process is a variant of the pad air-passage process. After impregnation, the material is subjected to hot drying on a drying cylinder. For final fixation of the dye, the material is impregnated with a cationic alkylating agent and redried. [Pg.374]

To place the mfp approach in a broader context, we now extend Eq. 1 to deal more explicitly with the ultimate formation of equilibrated product P [83]. In the case of weak D/A coupling, where a diabatic basis comprised of charge-localized valence-bond structures may be employed to represent the relevant states of the reacting system, the first-passage process can be viewed as the conversion of the activated reactants to the resonant state of activated products (El) subsequently e1 may recross to R (i.e., pass back through the hypersurface in configuration space defining the transition state) or proceed irreversibly to P ... [Pg.86]

In adiabatic passage processes with pulsed lasers, as we will discuss in the forthcoming sections, one often encounters the following particular situation If the initial condition of the photon field were a number state, that is,... [Pg.164]

S. Redner, A guide to First-Passage Processes, Cambridge University Press, Cambridge, UK,... [Pg.494]

When vacancies are present prior to the collision (e.g., by using highly stripped projectiles), the coupling region is passed twice. In this case, interference effects may occur so that the double passage process often exhibits oscillatory structures in the relevant excitation function. The oscillations are governed by the molecular potentials at relatively small intemuclear distances. Thus, the double-passage process reveals information about the molecular orbitals near the united atom limit. [Pg.416]

The same quantity but at smaller intemuclear distances is tested, when the double-passage process for vacancy transfer is examined. The transition probability exhibits oscillatory structures due to interferences between ingoing and outgoing parts of the collision. The related two-state formula shows that the oscillatory structure is superimposed on a smooth function already known from the single-passage process. Thus, the new information is implied in the oscillatory structure. The locations of the minima and maxima are determined by the difference of the related MO energies. Hence, the oscillatory structure allows for studying the formation of MO s at small... [Pg.472]

Fig. 9.3 Evolution of the population of the upper level in a two-level system, driven by a coherent radiation field (thin fine), by an incoherent radiation field (heavy line), and by an adiabatic-passage process (dashed line). The time scale is in units of the Rabi oscillation period. Fig. 9.3 Evolution of the population of the upper level in a two-level system, driven by a coherent radiation field (thin fine), by an incoherent radiation field (heavy line), and by an adiabatic-passage process (dashed line). The time scale is in units of the Rabi oscillation period.
The tunnel correction is not now a fundamentally defined number rather it is defined by the equation Q = kobJk, where kobs is the observed rate constant for a chemical reaction and k is that calculated on the basis of some model which is as good as possible except that it does not allow tunnelling. In this chapter the definition used for k is that calculated by absolute reaction rate theory [3], i.e., k = KRT/Nh)K where X is the equilibrium constant for the formation of the transition state. The factor k, the transmission coefficient, is also a quantum correction on the barrier passage process, but it is in the other direction, that is k < 1. We shall here follow the customary view (though it is not solidly based) that k is temperature-independent and not markedly less than unity. The term k is used following Bell [1] the s stands for semi-classical, that is quantum mechanics is applied to vibrations and rotations, but translation along the reaction coordinate is treated classically. [Pg.319]


See other pages where Passage Process is mentioned: [Pg.374]    [Pg.200]    [Pg.416]    [Pg.416]    [Pg.440]    [Pg.448]    [Pg.448]    [Pg.261]    [Pg.263]    [Pg.265]    [Pg.267]    [Pg.269]    [Pg.271]    [Pg.273]    [Pg.275]    [Pg.277]    [Pg.279]    [Pg.281]    [Pg.283]    [Pg.285]    [Pg.287]    [Pg.289]    [Pg.291]    [Pg.293]    [Pg.295]    [Pg.297]    [Pg.299]    [Pg.301]    [Pg.303]    [Pg.305]    [Pg.366]   


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