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INDEX elementary

Symmetry relations, derived from the spinor structure of (210) are extremely useful. To describe this, we need to make the dependence on the magnetic quantum numbers explicit, and we shall therefore replace the indices /i by the corresponding m, suppressing the other components of the multi-index. Elementary algebra shows that... [Pg.180]

We restrict our attention for the moment to elementary one-dimensional systems, so that each cell of the lattice is indexed by an integer i G Z and takes on one phase space, L 3 is a compact metric space under the metric... [Pg.248]

Consider an isotropic version of the elementary peripheral PCA introduced above, this time also with binary site variables time steps according to a set of rules determined by three conditional probabilities, po, p and p2 -... [Pg.345]

El theory In each case displacing material from the neutral plane makes the improvement in flexural stiffness. This increases the El product that is the geometry material index that determines resistance to flexure. The El theory applies to all materials (plastics, metals, wood, etc.). It is the elementary mechanical engineering theory that demonstrates some shapes resist deformation from external loads. [Pg.141]

Besides the elementary properties of index permutational symmetry considered in eq. (7), and intrinsic point group symmetry of a given tensor accounted for in eqs. (8)-(14), much more powerful group-theoretical tools [6] can be developed to speed up coupled Hartree-Fock (CHF) calculations [7-11] of hyperpolarizabilities, which are nowadays almost routinely periformed in a number of studies dealing with non linear response of molecular systems [12-35], in particular at the self-consistent-field (SCF) level of accuracy. [Pg.281]

Elementary probability theory shows [82] that on coupling f polydisperse arms onto a star center (this corresponds to an /-fold convolution of a most probable distribution) the polydispersity is reduced The polydispersity index of the star macromolecules (MJM is simply related to the polydispersity index of the arms as [80,82,83]... [Pg.138]

Mean molecular polarizability can be calculated through the Lorenz-Lorentz- Equation from refractive index, n, molecular weight, MW, and density, d, of a compound, demonstrating that the parameters can be derived from these elementary molecular properties (Figure 3). [Pg.263]

Only a limited discussion of the large field of organic chemistry can be given in the space allotted for this article. Consult alphabetical index for further information on specific topics. The reader is also directed to the references at the end of this article for examples of more detailed treatments of organic chemistry. Refs. Schmerltng Richey, and Morrison et al. represent texts dial heat organic chemistry at elementary, intermediate, and advanced levels, respectively,... [Pg.1168]

Since the dimensionless time for a first-order reaction is the product of the reaction time t and a first-order rate constant k, there is no reason why k(x)t should not be interpreted as k(x)t(x), that is, the reaction time may be distributed over the index space as well as the rate constant. Alternatively, with two indices k might be distributed over one and t over the other as k x)t(y). We can thus consider a continuum of reactions in a reactor with specified residence time distribution and this is entirely equivalent to the single reaction with the apparent kinetics of the continuum under the segregation hypothesis of residence time distribution theory, a topic that is in the elementary texts. Three indices would be required to distribute the reaction time with a doubly-distributed continuous mixture. [Pg.191]

The general character of the motion is shown in Fig. 1. A shock wave propagates in an unperturbed cold gas the maximum compression, which is dependent on the adiabatic index of the gas, is reached at the front of this wave. The velocity of propagation of the shock wave and the mass velocity at the front are related in an elementary way to the pressure of the shock wave. Behind the front the pressure, density, and velocity decrease.1... [Pg.107]

In Sect. Ill, the photoinduced refractive index variation in organic materials is discussed. The four elementary processes necessary for a PR effect are considered photogeneration, transport, and trapping of charged carriers, as well as the EO effect. [Pg.259]

Here NA and NK are the concentrations of molecules A and B on the surface, N0 is the number of elementary cells per unit surface, FA, FB and FA,B. are the non-configurational statistical sums of molecules A and B and of activated complex A B, z is the number of neighbouring cells (for a square cell z = 4), PAB i is the probability of two neighbouring cells being occupied by the AB pair and for this pair to have the environment marked by the index i, Ea is the energy difference between the pair AB and the activated complex A B provided that the cells that are nearer to both AB and A B are not occupied, and Ae is the energy difference between the interactions of both A B and AB with the environment. It is assumed that molecules A and B occupy one elementary cell and the activated complex occupies two of them. [Pg.68]

As the adspecies i can participate in various elementary reactions in the given total multistage processes, at common case the parameter sqp(f9lr) should have the additional indexes of the number a for the selected stage. Such an approach allows to apply an unified approach to considering the inhomogeneity of adspecies distribution, caused by their interaction with the different lattice sites and interaction between each other. (As the number of the site / and its type q are unambiguously related so that the parameters notation can be simplified il(r) — p(fg r), 4 (/l ) = 4 , etc). [Pg.375]

All two-site elementary processes are realized on the two nearest neighboring sites / and g. So the index r — 1 is omitted in U]g(r a) and below in multipliers KJ (r a). The addends on the right-hand sides of Eq. (41) are the rates of the elementary processes (whose stage numbers a are indicated in parentheses), the particles participating in an elementary process are defined by superscripts, and the site numbers, by subscripts. [Pg.384]

The summands of Eq. (61) correspond to the elementary stages of adsorption, desorption, and the reaction, respectively. The rate constants and the functions S,(ot) contain an additional index a which denotes stage number. This allows to distinguish between the elementary processes where adspecies i can be involved. Thus adspecies A is capable of being desorbed or reacting with molecule B, and the properties of the AC resulting from these elementary processes will be different (i (oc = l F a = 2) and sAA(oc = = 2)). Thus, considering the non-ideality increases the... [Pg.400]

This defines a Gateaux functional derivative [26, 102], whose value depends on a direction in the function space, reducing to a Frechet derivative only if all e, are equal. Defining Tt = t + v, an explicit orbital index is not needed if Eq. (5.10) is interpreted to define a linear operator acting on orbital wave functions, TL — v = t. The elementary chain rule is valid when the functional... [Pg.74]

Equations (7.53) simplify if the system has point-group or translational symmetry. Then local basis functions of equivalent cells are related to those of a smaller number of generating cells by phase factors and elementary rotations. Considering only translational symmetry, it is convenient to index cells in a reference translational cell by indices /x, etc. and to index translated equivalent cells by the corresponding indices jl, etc., such that the displacement of cell if, relative to cell t,... [Pg.127]

In this chapter we have reviewed a number of techniques used for optical characterization of organic samples, in particular those concerning the determination of complex optical constants and the dynamics of elementary photoexcitations. It has been stressed that very good optical quality samples are needed in order to obtain reliable estimates of the refractive index. In general, samples with controlled morphology, low defect and impurity concentration, and good optical quality allow more reliable photophysical studies and hence better determination of the intrinsic properties of the material. [Pg.80]

Adair and Robinson (1) indicate that the refractive index of a protein or an amino acid is approximately determined by its elementary composition however, the structure of a molecule is also of importance. The values reported for amino acids are scattered and fragmentary (1, 10), and prior to our preliminary communication (25) no systematic investigation had accounted quantitatively for the relationship... [Pg.77]

AN INTRODUCTION TO ORDINARY DIFFERENTIAL EQUATIONS. Earl A. Coddington. A thorough and systematic first course in elementary differential equations for undergraduates in mathematics and science, with many exercises and problems (with answers). Index. 304pp. 5b x 8b. 65942-9 Pa. 7.95... [Pg.129]

The crudest approximation to the density matrix for the system is obtained by assuming that there are no statistical correlations between the elementary excitations (perfect fluid), so that can be written as a simple product of molecular density matrices A. A better approximation is obtained if one does a quantum field theory calculation of the local field effects in the system which in a certain approximation gives the Lorentz-Lorenz correction L(TT) in terms of the refractive index n53). One then writes,... [Pg.23]


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See also in sourсe #XX -- [ Pg.185 ]




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Elementary processes INDEX

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