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Asymmetric coefficient

The FMO coefficients also allow cpralitative prediction of the kinetically controlled regioselectivity, which needs to be considered for asymmetric dienes in combination with asymmetric dienophiles (A and B in Scheme 1.1). There is a preference for formation of a o-bond between the termini with the most extreme orbital coefficients ... [Pg.6]

Head coefficient, 156 Head equation, adiabatic, 3 t Head equation, poly tropic, I Head, centrifugal, 156 Head, reciprocating, 58 Heat run test (dry), 413 Helical compressor, 5, 7 adiabatic efficiency, Itil applicalion mnge, 7. ly asymmetric profile, 96 bearings, 116 capacity control, 95 casings, 114 circular profile, 95 cooling, I i 1 discharge temperature (dry), I 17... [Pg.546]

The number of asymmetric carbon atoms in this formula is a 3 the number of distinct stereoisomers is 4, not 8 the difference 8-4 appears in (3.1) as the first coefficient.]... [Pg.67]

It should be kept in mind that all transport processes in electrolytes and electrodes have to be described in general by irreversible thermodynamics. The equations given above hold only in the case that asymmetric Onsager coefficients are negligible and the fluxes of different species are independent of each other. This should not be confused with chemical diffusion processes in which the interaction is caused by the formation of internal electric fields. Enhancements of the diffusion of ions in electrode materials by a factor of up to 70000 were observed in the case of LiiSb [15]. [Pg.532]

PROS REJECT jcls Section 3.6, Fig. 1.29 In a production environment there are often several superimposed processes that yield measurement series like that depicted in the lower panel there is drift that unexpectedly changes slope, there is bias and measurement noise, and there are operators who take corrective action. The model includes the probability of drift occurring and a feed-back loop that permits both positive and negative coefficients. The operators can be ordered to react if a single value exceeds a set limit, or only if 2, 3, or more successive values do so. The program calculates the two-sided (asymmetric) total probability of a value being OOS and depicts this in the upper panel on a log(p) scale. The red horizontal is the upper limit on the total risk as set in cell B20. [Pg.398]

The theory has been verified by voltammetric measurements using different hole diameters and by electrochemical simulations [13,15]. The plot of the half-wave potential versus log[(4d/7rr)-I-1] yielded a straight line with a slope of 60 mV (Fig. 3), but the experimental points deviated from the theory for small radii. Equations (3) to (5) show that the half-wave potential depends on the hole radius, the film thickness, the interface position within the hole, and the diffusion coefficient values. When d is rather large or the diffusion coefficient in the organic phase is very low, steady-state diffusion in the organic phase cannot be achieved because of the linear diffusion field within the microcylinder [Fig. 2(c)]. Although no analytical solution has been reported for non-steady-state IT across the microhole, the simulations reported in Ref. 13 showed that the diffusion field is asymmetrical, and concentration profiles are similar to those in micropipettes (see... [Pg.382]

This follows because, in the grouped representation, Q+ contains nonzero blocks only on the diagonal and is symmetric, and Q contairisnonzero blocks only off the diagonal and is asymmetric. These symmetry rules are called the Onsager-Casimir reciprocal relations [10, 24], They show that the magnitude of the coupling coefficient between a flux and a force is equal to that between the force and the flux. [Pg.19]

A common method to measure diffusion coefficients consists in the welding of two samples with different concentrations of the element of which the diffusion coefficient is to be known. Upon heating, diffusion asymmetrical profiles are quite commonly obtained which show that different species diffuse at different rates. The concentration-... [Pg.423]

In most cases, fluorescent molecules undergo anisotropic rotations because of their asymmetry. A totally asymmetric rotor has three different rotational diffusion coefficients, and in cases where the absorption and emission transition moments are not directed along one of the principal diffusion axes, the decay of r(t) is a sum of five exponentials (see Box 5.3). [Pg.147]

If only N-substituted aniline derivatives are considered, the IP( 2) value is observed close to that of the parent compound and to vary in a rather narrow range (8.8-9.1 eV). On the other hand, for IPfe) (7.0-7.7 eV) and IP(rtN) (9.5-10.3 eV) larger deviations relative to unsubstituted aniline and greater variation with substitution are found. This can be explained by perturbations of the corresponding benzene MOs by the substituents which is minimal for H2, because it has no coefficients on C-l and N (Cs symmetry). In asymmetric aniline derivatives also JI2 is expected to interact to a substantial extent with n n-... [Pg.174]

For aqueous solutions of salts, lt, (P, 7) represents the chemical potential of pure ions. This chemical potential cannot be measnred experimentally. Instead of nsing this hypothetical standard state, the activity coefficients of ions often are normalized by introducing the asymmetrical activity coefficient, y,, defined as... [Pg.32]

Membrane deterioration may be merely caused by decrease of acetyl content(C ) in the active surface layer as a result of hydrolysis or oxidation, not by structure change. Analysis was carried out based on solution-diffusion model proposed by Lonsdale etal( ), using their measured values of solute diffusivity and partition coefficient in homogeneous membrnaes of various degree of acetyl content and also using those values of asymmetric membranes heat treated at various temperatures measured by Glueckauf(x) ... [Pg.123]


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See also in sourсe #XX -- [ Pg.344 ]




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