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Characteristic values invariance

In both treatments, the in vivo light absorption characteristics were invariable over the day (data not shown). Maximum values in the chlorophyll-specific absorption coefficient were observed near 675 nm (Chi a), 470 nm (carotenoids) and 430 nm (Chi a) (Fig. 4). The absorption cross section was 0.057 m2 mg Chi a 1 under iron limitation and... [Pg.66]

Thus, when each of the invariants contributes alone, a characteristic value of p results ... [Pg.39]

Using the scaling relation to deduce the relaxation times or viscosities at elevated pressure, we find that the characteristic value of r or at the onset of Arrhenius behavior is invariant to pressure. [Pg.60]

Generalization of the characteristic value problem. The characteristic value problem can be formulated as the quest for the irreducible linear manifolds which are invariant under an operator. The principal result of the spectral theory of normal operators can be formulated, from this point of view, as the statement that all irreducible linear manifolds of normal operators are one-dimensional. Similarly, one can ask for irreducible closed linear manifolds which are invariant under a set of operators. Since a closed linear manifold which is invariant under a set of operators is also invariant under the group or algebra generated by these operators, one is naturally led in this way to a linear manifold which belongs to an irreducible representation of a group or an algebra. [Pg.469]

I br the majority of physicaJ systems, the Lagrangian is invariant to any space translation. In this case, all the equations of the theory cam be simplified by means of Fourier s transformation, i.e. by considering the characteristic values in the momentum space. 1 he rules for drawing graphs of the characteristic values in the momentum space are given. [Pg.251]

The probabilistic models of actions are related to their characteristic values used for the determination of the design values of actions (see Table 1). The permanent action is described by normal distribution (N), variable actions by Gumbel distribution (GUM) and material strength by lognormal distribution (LN). These models are primarily intended as conventional models in time invariant reliability analysis of structural members using Turkstra s combination rule, see e.g. Holicky (2013). [Pg.2209]

Fig. 68. - Intercorrelation of kinetic parameters characterizing reaction mechanism. Left, the relationship between the single exponent, r (as a characteristic exponent of JMAYK equation, -/ (/ - a) = (ktT) 0 ) and the twin exponents, m and n (as characteristic exponents of SB equation ( - c d") demonstrating mutual relation between the two most frequent models, JMAYK and SB, Right, the plot of characteristic values of cry and a/derived on the basis of accredited functions = A f(a) and s(a). f(a g(a). which stay invariant on temperature and heating. The dotted lines show the idealized effect of kinetic exponents, m and n, of the SB kinetic model though such discrete values cannot be expected while studying any real solid-state process. It remains to determine the condition for the functions maximum, which can be derived y (a) == A fia ) 0 and z (cd = f(oti) g(az) + / = t), where the characteristic vaiues of oy and a-/ correspond to the maximum of the y(a) and z(a) functions for different kinetic models, dander and R2 nr/ = 0 and az = 0.75, R3 a/ = 0 and ctz = 0.704, 2D-diffusion a = 0 and 0.834, Ginsding-Brounsfein ay 0 and orz " 0.776, JMAYK a> = t - exp I/m-I)f and nr/= 0.632, RO a/ = 0 and J — SB ay = m/(m+n) and az > ay. The shadowed area marks certain theoretical thresliold for kiiielic models applicability. Fig. 68. - Intercorrelation of kinetic parameters characterizing reaction mechanism. Left, the relationship between the single exponent, r (as a characteristic exponent of JMAYK equation, -/ (/ - a) = (ktT) 0 ) and the twin exponents, m and n (as characteristic exponents of SB equation ( - c d") demonstrating mutual relation between the two most frequent models, JMAYK and SB, Right, the plot of characteristic values of cry and a/derived on the basis of accredited functions = A f(a) and s(a). f(a g(a). which stay invariant on temperature and heating. The dotted lines show the idealized effect of kinetic exponents, m and n, of the SB kinetic model though such discrete values cannot be expected while studying any real solid-state process. It remains to determine the condition for the functions maximum, which can be derived y (a) == A fia ) 0 and z (cd = f(oti) g(az) + / = t), where the characteristic vaiues of oy and a-/ correspond to the maximum of the y(a) and z(a) functions for different kinetic models, dander and R2 nr/ = 0 and az = 0.75, R3 a/ = 0 and ctz = 0.704, 2D-diffusion a = 0 and 0.834, Ginsding-Brounsfein ay 0 and orz " 0.776, JMAYK a> = t - exp I/m-I)f and nr/= 0.632, RO a/ = 0 and J — SB ay = m/(m+n) and az > ay. The shadowed area marks certain theoretical thresliold for kiiielic models applicability.
The XRD peaks characteristic of Co and Ni disappeared after the treatment, as did the broad ESR line, successfully leaving only the narrow asymmetric line with 26 G linewidth as shown in Fig. 8 [40]. The g-value of the narrow line is =2.002 0.001. The narrow ESR line shows Dysonian at all temperatures in the range of 4-300 K. Furthermore, the ESR intensity is quite independent of T and thus the density of conduction electrons is invariant as a function of temperature as shown in Fig. 9. These show that the material is highly metallic, even at low 7. [Pg.85]

It is shown that an increase in the heat flux is accompanied by an increase in the liquid and vapor velocities, the meniscus displacement towards the outlet cross-section, as well as growth of vapor to liquid forces ratio and heat losses. When is large enough, the difference between the intensity of heat transfer and heat losses are limited by some final value, which determines the maximum rate of vaporization. Accordingly, when is large all characteristic parameters are practically invariable. [Pg.433]

We see that the expression for the current consists of two terms. The first term depends on time and coincides completely with Eq. (11.14) for transient diffusion to a flat electrode. The second term is time invariant. The first term is predominant initially, at short times t, where diffusion follows the same laws as for a flat electrode. During this period the diffusion-layer thickness is still small compared to radius a. At longer times t the first term decreases and the relative importance of the current given by the second term increases. At very long times t, the current tends not to zero as in the case of linear diffusion without stirring (when is large) but to a constant value. For the characteristic time required to attain this steady state (i.e., the time when the second term becomes equal to the first), we can write... [Pg.190]

The packed bed breakthrough method for investigation of mass transfer phenomena in sorbent systems can in many instances offer certain advantages not found in other experimental methods. The method is especially useful when the adsorption isotherms for the principal sorbate exhibit favorable curvature (convex toward loading axis). In such a case, there is the potential for a portion of the sorption front to approach a stable wave form (shape of the front invariant with time). Given the existence of a stable or "steady-state" mass transfer zone (MTZ) and a detailed knowledge of the equilibrium loading characteristics within that zone, one can extract local values of the effective mass transfer resistance at any concentration in the zone. [Pg.74]


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See also in sourсe #XX -- [ Pg.264 ]




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Characteristic value

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