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Analytical expression for

For each frequency 100 points were taken along a line running from the surface of the conductor into a depth of 30 mm in that region below the coil, where the maximum eddy currents are located (dashed vertical lines in the sketch). These data are fitted by appropriate polynomials to obtain an analytical expression for s (to, z) in the frequency and depth interval mentioned above. [Pg.256]

Solving this diflfiision problem yields an analytical expression for the time-dependent escape probability q(t) ... [Pg.860]

Voth G A 1990 Analytic expression for the transmission coefficient in quantum mechanical transition state theory Chem. Phys. Lett. 170 289... [Pg.897]

A further model Hamiltonian that is tailored for the treatment of non-adiabatic systems is the vibronic coupling (VC) model of Koppel et al. [65]. This provides an analytic expression for PES coupled by non-adiabatic effects, which can be fitted to ab initio calculations using only a few data points. As a result, it is a useful tool in the description of photochemical systems. It is also very useful in the development of dynamics methods, as it provides realistic global surfaces that can be used both for exact quantum wavepacket dynamics and more approximate methods. [Pg.255]

A drawback of the SCRF method is its use of a spherical cavity molecules are rarely exac spherical in shape. However, a spherical representation can be a reasonable first apprc mation to the shape of many molecules. It is also possible to use an ellipsoidal cavity t may be a more appropriate shape for some molecules. For both the spherical and ellipsoi cavities analytical expressions for the first and second derivatives of the energy can derived, so enabling geometry optimisations to be performed efficiently. For these cavil it is necessary to define their size. In the case of a spherical cavity a value for the rad can be calculated from the molecular volume ... [Pg.611]

Since the Flory-Huggins theory provides us with an analytical expression for AG , in Eq. (8.44), it is not difficult to carry out the differentiations indicated above to consider the critical point for miscibility in terms of the Flory-Huggins model. While not difficult, the mathematical manipulations do take up too much space to include them in detail. Accordingly, we indicate only some intermediate points in the derivation. We begin by recalling that (bAGj Ibn ) j -A/ii, so by differentiating Eq. (8.44) with respect to either Ni or N2, we obtain... [Pg.532]

The iategral can be found graphically if the equiUbrium line is curved. An analytical expression for the iategral is available for the case where both the equihbrium and operating lines are linear (5) ... [Pg.68]

Total Upflow in an Ideal Plant. The sum of the upflows from all of the stages in the ideal plant, or more simply, the total upflow, is the area enclosed by the cascade shown in Figure 4. An analytical expression for this quantity is obtained as the summation of all the stage upflows in the enriching section expressed as an integral ... [Pg.81]

The widespread availabihty and utihzation of digital computers for distillation calculations have given impetus to the development of analytical expressions for iregression equation and accompanying regression coefficients that represent the DePriester charts of Fig. 13-14. Regression equations and coefficients for various versions of the GPA convergence-pressure charts are available from the GPA. [Pg.1254]

The amplitude of the elastic scattering, Ao(Q), is called the elastic incoherent structure factor (EISF) and is determined experimentally as the ratio of the elastic intensity to the total integrated intensity. The EISF provides information on the geometry of the motions, and the linewidths are related to the time scales (broader lines correspond to shorter times). The Q and ft) dependences of these spectral parameters are commonly fitted to dynamic models for which analytical expressions for Sf (Q, ft)) have been derived, affording diffusion constants, jump lengths, residence times, and so on that characterize the motion described by the models [62]. [Pg.479]

Two types of boundary conditions are considered, the closed vessel and the open vessel. The closed vessel (Figure 8-36) is one in which the inlet and outlet streams are completely mixed and dispersion occurs between the terminals. Piston flow prevails in both inlet and outlet piping. For this type of system, the analytic expression for the E-curve is not available. However, van der Laan [22] determined its mean and variance as... [Pg.736]

The analytical expression for the Kekule type has also been derived [16] but omitted here for simplicity. [Pg.44]

Since only one molecule is added to (or removed from) the system, U is simply the interaction of the added (or removed) molecule with the remaining ones. If one attempts to add a new molecule, N is the number of molecules after addition, otherwise it is the number of molecules prior to removal. If a cutoff for the interaction potential is employed, long-range corrections to must be taken into account because of the density change of /As. Analytic expressions for these corrections can be found in the appendix of Ref. 33. [Pg.26]

The importance of the method in corrosion testing and research has stimulated other work, and since Stern s papers appeared there have been a number of publications many of which question the validity of the concept of linear polarisation. The derivation of linearity polarisation is based on an approximation involving the difference of two exponential terms, and a number of papers have appeared that have attempted to define the range of validity of polarisation resistance measurements. Barnartt" derived an analytical expression for the deviations from linearity and concluded that it varied widely between different systems. Leroy", using mathematical and graphical methods, concluded that linearity was sufficient for the technique to be valid in many practical corrosion systems. Most authors emphasise the importance of making polarisation resistance measurements at both positive and negative overpotentials. [Pg.1012]

In Ref. [4], the soliton lattice configuration and energy within the SSH model were found numerically. Analytical expressions for these quantities can be obtained in the weak-coupling limit, when the gap 2A() is much smaller than the width of the re-electron band 4/0. At this point it is useful to define the lattice correlation length ... [Pg.47]

Various modifications of the Flory theory [4] are usually applied to describe the uncharged gels. Their crosslinking density can be simply calculated from the swelling degree using Eqs. (3.1) and (3.2) or analytical expressions for the Mc value (see, for example, Ref. [124]). [Pg.119]

Subscripts w and a are introduced to distinguish between the constant temperature of the spots where the pressure is monitored and the system is pumped out, and the changing temperature of the heated adsorbent, respectively. If the experimental conditions are such that the term with dP/dt can be neglected, Eq. (13) gives directly the dependence of the pressure in the system on the adsorbent temperature and even on the time t elapsed from the beginning of the experiment, if an analytical expression for the heating rate is available. The time derivative of Eq. (13) gives for... [Pg.358]

Marcus theory. Prove the point that A = 4AGJ by making use of the analytic expressions for the equation of a parabola. The two equations should be those that describe the curves on the left side of Fig. 10-11. [Pg.251]

TABLE 2. Analytical expressions for some symmetry coordinates" in dimethyl sulphoxide and dimethyl sulphone11... [Pg.15]

The potential surfaces Eg, Hn, and H22 of the HF molecule are described in Fig. 1.6. These potential surfaces provide an instructive example for further considerations of our semiempirical strategy (Ref. 5). That is, we would like to exploit the fact that Hn and H22 represent the energies of electronic configurations that have clear physical meanings (which can be easily described by empirical functions), to obtain an analytical expression for the off-diagonal matrix element H12. To accomplish this task we represent Hn, H22, and Eg by the analytical functions... [Pg.19]

Analytical Expression for Potential-Dependent Microwave Conductivity... [Pg.461]

Example 3.2 Consider the reaction 2A B. Derive an analytical expression for the fraction unreacted in a gas-phase, isothermal, piston flow reactor of length L. The pressure drop in the reactor is negligible. [Pg.87]

Equations 22 and 23 can be solved numerically using the method described in Ref. 5. For oligomers, the probability generating functions are calculated by the appropriate sums. For random copolymers analytical expressions for and t can be written for a polymer or crosslinker using the appropriate Schulz-Zimm parameters (5) ... [Pg.196]

Ohshima, H Healy, T White, LR, Approximate Analytic Expressions for the Electrophoretic Mobility of Spherical Colloidal Particles and the Conductivity of their Dilute Suspensions, Journal of the Chemical Society, Faraday Transactions 79, 1613, 1983. [Pg.617]

The orders of reaction, U , ivith respect to A, B and AB are obtained from the rate expression by differentiation as in Eq. (11). In the rare case that we have a complete numerical solution of the kinetics, as explained in Section 2.10.3, we can find the reaction orders numerically. Here we assume that the quasi-equilibrium approximation is valid, ivhich enables us to derive an analytical expression for the rate as in Eq. (161) and to calculate the reaction orders as ... [Pg.63]

When the more general Mie scattering theory is applied the approach adopted in deriving the previous fomulae cannot he used. One is, however, able to derive an analytical expression for the moments of the size distribution within the detector cell. They are given as ... [Pg.66]


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Analytical expressions

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