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Transformation three coefficients

The components of a symmetrical second-rank tensor, referred to its principal axes, transform like the three coefficients of the general equation of a second-degree surface (a quadric) referred to its principal axes (Nye, 1957). Hence, if all three of the quadric s coefficients are positive, an ellipsoid becomes the geometrical representation of a symmetrical second-rank tensor property (e.g., electrical and thermal conductivity, permittivity, permeability, dielectric and magnetic susceptibility). The ellipsoid has inherent symmetry mmm. The relevant features are that (1) it is centrosymmetric, (2) it has three mirror planes perpendicular to the... [Pg.7]

As the coefficient at y2 vanishes, transformation (2.35) cannot be performed, for the four unknown coefficients a, b, c, d in equation (2.37) cannot be determined by means of the three coefficients A20, Allt A02. [Pg.55]

Kea.tlte, Keatite has been prepared (65) by the crystallisation of amorphous precipitated silica ia a hydrothermal bomb from dilute alkah hydroxide or carbonate solutions at 380—585°C and 35—120 MPa (345—1180 atm). The stmcture (66) is tetragonal. There are 12 Si02 units ia the unit cell ttg = 745 pm and Cg = 8604 pm the space group is P42. Keatite has a negative volumetric expansion coefficient from 20—550°C. It is unchanged by beating at 1100°C, but is transformed completely to cristobahte ia three hours at 1620°C. [Pg.476]

Obviously, the theory outhned above can be applied to two- and three-dimensional systems. In the case of a two-dimensional system the Fourier transforms of the two-particle function coefficients are carried out by using an algorithm, developed by Lado [85], that preserves orthogonality. A monolayer of adsorbed colloidal particles, having a continuous distribution of diameters, has been investigated by Lado. Specific calculations have been carried out for the system with the Schulz distribution [86]... [Pg.156]

As a result the research emphasis in this field focused on efforts to design experiments in which it might be possible to determine to which one of the foregoing three rate equations the observed second-order rate coefficient actually corresponded. More specifically, the objective was to observe one and the same system first under conditions in which complex decomposition (fcp) was rate-determining and then under conditions in which complex formation (kF) was ratedetermining. A system in which either formation or decomposition was subject to some form of catalysis was thus indicated. In displacements with primary and secondary amines the transformation of reactants to products necessarily involves the transfer of a proton at some stage of the reaction. Such reactions are potential-... [Pg.409]

Correspondence factor analysis can be described in three steps. First, one applies a transformation to the data which involves one of the three types of closure that have been described in the previous section. This step also defines two vectors of weight coefficients, one for each of the two dual spaces. The second step comprises a generalization of the usual singular value decomposition (SVD) or eigenvalue decomposition (EVD) to the case of weighted metrics. In the third and last step, one constructs a biplot for the geometrical representation of the rows and columns in a low-dimensional space of latent vectors. [Pg.183]

Using the valence profiles of the 10 measured directions per sample it is now possible to reconstruct as a first step the Ml three-dimensional momentum space density. According to the Fourier Bessel method [8] one starts with the calculation of the Fourier transform of the Compton profiles which is the reciprocal form factor B(z) in the direction of the scattering vector q. The Ml B(r) function is then expanded in terms of cubic lattice harmonics up to the 12th order, which is to take into account the first 6 terms in the series expansion. These expansion coefficients can be determined by a least square fit to the 10 experimental B(z) curves. Then the inverse Fourier transform of the expanded B(r) function corresponds to a series expansion of the momentum density, whose coefficients can be calculated from the coefficients of the B(r) expansion. [Pg.317]

The major differences between behavior profiles of organic chemicals in the environment are attributable to their physical-chemical properties. The key properties are recognized as solubility in water, vapor pressure, the three partition coefficients between air, water and octanol, dissociation constant in water (when relevant) and susceptibility to degradation or transformation reactions. Other essential molecular descriptors are molar mass and molar volume, with properties such as critical temperature and pressure and molecular area being occasionally useful for specific purposes. A useful source of information and estimation methods on these properties is the handbook by Boethling and Mackay (2000). [Pg.3]

The coefficients /, g, and h are unique for each second-harmonic signal and depend on the three susceptibility tensors. We normalize the relative values of the tensor components to = 1- The task is then to determine the complex values of the other 14 tensor components (see Table 9.2). A sufficient number of 8 independent measurements is provided by the p- and s--polarized components of the reflected and transmitted second-harmonic signals for the two orientations of the sample shown in Figure 9.17. The change in sample orientation corresponds to a coordinate transformation that reverses the... [Pg.550]

Equation (9.15) was written for macro-pore diffusion. Recognize that the diffusion of sorbates in the zeoHte crystals has a similar or even identical form. The substitution of an appropriate diffusion model can be made at either the macropore, the micro-pore or at both scales. The analytical solutions that can be derived can become so complex that they yield Httle understanding of the underlying phenomena. In a seminal work that sought to bridge the gap between tractabUity and clarity, the work of Haynes and Sarma [10] stands out They took the approach of formulating the equations of continuity for the column, the macro-pores of the sorbent and the specific sorption sites in the sorbent. Each formulation was a pde with its appropriate initial and boundary conditions. They used the method of moments to derive the contributions of the three distinct mass transfer mechanisms to the overall mass transfer coefficient. The method of moments employs the solutions to all relevant pde s by use of a Laplace transform. While the solutions in Laplace domain are actually easy to obtain, those same solutions cannot be readily inverted to obtain a complete description of the system. The moments of the solutions in the Laplace domain can however be derived with relative ease. [Pg.285]

The hyperspherical method, from a formal viewpoint, is general and thus can be applied to any N-body Coulomb problem. Our analysis of the three body Coulomb problem exploits considerations on the symmetry of the seven-dimensional rotational group. The matrix elements which have to be calculated to set up the secular equation can be very compactly formulated. All intervals can be written in closed form as matrix elements corresponding to coupling, recoupling or transformation coefficients of hyper-angular momenta algebra. [Pg.298]

Performing the summation of the products of Clebsch-Gordan coefficients over all projection parameters, we obtain the invariants, called 3n/-coefficients. Their trivial cases were presented in Figs 8.6b-e (Kro-necker and triangular deltas). The first non-trivial case is represented by formula (6.16) or the transformation matrix of three angular momenta, connected with 6/-coefficient (see formula (6.42) and Fig. 8.7)). [Pg.68]

The transformation matrices of four momenta lead to 9/-coefficients. As in the case of three momenta, one and the same matrix can correspond to a number of graphs. Their common feature is that each graph has six vertices and nine lines. Here we shall present only two diagrams (Fig. 8.8a,b), corresponding to the transformation matrices (6.43) and... [Pg.68]

In (12.15) we have the two usual transformation matrices (see Chapter 6), describing the change of the coupling of three momenta, and two more for four momenta. Expressing them in terms of 6j- and 97-coefficients according to formulas (6.42)-(6.44), we get the final form of the transfer-... [Pg.100]

A completely different model is given by Richards and Parks (1971). It is based on modified von Kries coefficients. If we assume that the sensor response functions have the shape of delta functions, then it is possible to transform a given color of a patch taken under one illuminant to the color of the patch when viewed under a different illuminant by multiplying the colors using three constant factors for the three channels. These factors are known as von Kries coefficients, as described in Section 4.6. The von Kries coefficients are defined as... [Pg.322]


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See also in sourсe #XX -- [ Pg.131 , Pg.133 ]




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Transformation coefficient

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