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Derivative inversion

Alkenes from vie-diols (cf. 9, 507-508). Hexapyranosidc rc-diols arc converted into alkenes by reaction with this combination of reagents. The method is applicable to both cis- and trons-diols, but highest yields of alkenes arc usually obtained from diequatorial tra/is-diols. The reaction is believed to involve formation of a nrc-diiodide derivative (inversion), which then undergoes reductive elimination with imidazole. [Pg.450]

Usually, only two or three colorants are added. Due to this reason and taking into account the economic feasibility and rapidity, double division-ratio spectra derivative, inverse least-squares, and principal component regression methods are reliable for the simultaneous determination of the colorants in the drinks without a priority procedure such as separation, extraction, and preconcentration. [Pg.1519]

Apply the thermodynamic web to relate measured, fundamental, and derived thermodynamic properties. In doing so, apply the fundamental property relations. Maxwell relations, the chain rule, derivative inversion, the cyclic relation, and Equations (5.22), (5.23), and (5.24). Use Figure 5.3 to rewrite partial derivatives with T,P,s, and v in more convenient forms. [Pg.265]

Derivative inversion allows us to flip partial derivatives as follows ... [Pg.272]

Solving Equation (E5.1A) for dy using derivative inversion gives ... [Pg.273]

Rearranging Equation (E5.1D) and applying derivative inversion, we get the cyclic rule ... [Pg.273]

Figure 5.3 presents a way to navigate the thermodynamic web when partial derivatives with T,P,s, and v are encountered. It provides 12 permutations of partial derivatives between these properties. Derivative inversion can also be applied to form 12 additional... [Pg.273]

For a system with constant composition, the two properties that we choose to constrain the state of the system become the independent properties. We can write the differential change of any other property, the dependent property, in terms of these two properties, as illustrated by Equation (5.4). From a combined form of the first and second laws, we developed the fundamental property relations. We then used the rigor of mathematics to allow us to form this intricate web of thermodynamic relationships. Included in the web are the Maxwell relations, the chain rule, derivative inversion, the cyclic relation, and Equations (5.22) through (5.24). A set of useful relationships relating partial derivatives with T, P, s, and v is summarized in Figure 5.3. We use these relationships to solve first- and second-law problems similar to those in Chapters 2 and 3, but for real fluids. [Pg.304]

This paper is structured as follows in section 2, we recall the statement of the forward problem. We remind the numerical model which relates the contrast function with the observed data. Then, we compare the measurements performed with the experimental probe with predictive data which come from the model. This comparison is used, firstly, to validate the forward problem. In section 4, the solution of the associated inverse problem is described through a Bayesian approach. We derive, in particular, an appropriate criteria which must be optimized in order to reconstruct simulated flaws. Some results of flaw reconstructions from simulated data are presented. These results confirm the capability of the inversion method. The section 5 ends with giving some tasks we have already thought of. [Pg.327]

N. B. a has the inverse role of a in the first derivative of a Gaussian. Deriche proposes the following recursive implementation of the filter/in two dimensions. Deriche retains the same solution as Canny, that is ... [Pg.527]

This orientation interaction thus varies inversely with the sixth power of the distance between dipoles. Remember, however, that the derivation has assumed separations large compared with d. [Pg.227]

For each collision there is an inverse one, so we can also express the time derivative of the //-fiinction in temis of the inverse collisions as... [Pg.684]

Figure B2.4.8. Relaxation of two of tlie exchanging methyl groups in the TEMPO derivative in figure B2.4.7. The dotted lines show the relaxation of the two methyl signals after a non-selective inversion pulse (a typical experunent). The heavy solid line shows the recovery after the selective inversion of one of the methyl signals. The inverted signal (circles) recovers more quickly, under the combined influence of relaxation and exchange with the non-inverted peak. The signal that was not inverted (squares) shows a characteristic transient. The lines represent a non-linear least-squares fit to the data. Figure B2.4.8. Relaxation of two of tlie exchanging methyl groups in the TEMPO derivative in figure B2.4.7. The dotted lines show the relaxation of the two methyl signals after a non-selective inversion pulse (a typical experunent). The heavy solid line shows the recovery after the selective inversion of one of the methyl signals. The inverted signal (circles) recovers more quickly, under the combined influence of relaxation and exchange with the non-inverted peak. The signal that was not inverted (squares) shows a characteristic transient. The lines represent a non-linear least-squares fit to the data.
In order for Am to be a regular matrix at every point in the assumed region of configuration space it has to have an inverse and its elements have to be analytic functions in this region. In what follows, we prove that if the elements of the components of Xm are analytic functions in this region and have derivatives to any order and if the P subspace is decoupled from the corresponding Q subspace then, indeed. Am will have the above two features. [Pg.717]

Xk) is the inverse Hessian matrix of second derivatives, which, in the Newton-Raphson method, must therefore be inverted. This cem be computationally demanding for systems u ith many atoms and can also require a significant amount of storage. The Newton-Uaphson method is thus more suited to small molecules (usually less than 100 atoms or so). For a purely quadratic function the Newton-Raphson method finds the rniriimum in one step from any point on the surface, as we will now show for our function f x,y) =x + 2/. [Pg.285]

The described direct derivation of shape functions by the formulation and solution of algebraic equations in terms of nodal coordinates and nodal degrees of freedom is tedious and becomes impractical for higher-order elements. Furthermore, the existence of a solution for these equations (i.e. existence of an inverse for the coefficients matrix in them) is only guaranteed if the elemental interpolations are based on complete polynomials. Important families of useful finite elements do not provide interpolation models that correspond to complete polynomial expansions. Therefore, in practice, indirect methods are employed to derive the shape functions associated with the elements that belong to these families. [Pg.25]

Differentiation of locally defined shape functions appearing in Equation (2.34) is a trivial matter, in addition, in isoparametric elements members of the Jacobian matrix are given in terms of locally defined derivatives and known global coordinates of the nodes (Equation 2.27). Consequently, computation of the inverse of the Jacobian matrix shown in Equation (2.34) is usually straightforward. [Pg.38]

DERIV. Calculates the inverse of the Jacobian matrix used in isoparametric transformations. [Pg.211]

For homonuclear molecules (e.g., O2, N2, etc.) the inversion operator i (where inversion of all electrons now takes place through the center of mass of the nuclei rather than through an individual nucleus as in the atomic case) is also a valid symmetry, so wavefunctions F may also be labeled as even or odd. The former functions are referred to as gerade (g) and the latter as ungerade (u) (derived from the German words for even and odd). The g or u character of a term symbol is straightforward to determine. Again one... [Pg.262]


See other pages where Derivative inversion is mentioned: [Pg.490]    [Pg.173]    [Pg.46]    [Pg.35]    [Pg.54]    [Pg.401]    [Pg.39]    [Pg.124]    [Pg.490]    [Pg.173]    [Pg.46]    [Pg.35]    [Pg.54]    [Pg.401]    [Pg.39]    [Pg.124]    [Pg.109]    [Pg.424]    [Pg.73]    [Pg.171]    [Pg.1678]    [Pg.2109]    [Pg.2334]    [Pg.422]    [Pg.250]    [Pg.286]    [Pg.286]    [Pg.310]    [Pg.310]    [Pg.490]    [Pg.191]    [Pg.276]    [Pg.70]    [Pg.18]    [Pg.160]    [Pg.319]    [Pg.217]    [Pg.129]   
See also in sourсe #XX -- [ Pg.272 , Pg.273 ]




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