Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Gradient elements

Show that the gradient elements given by equation (4 9) are identically zero if the orbital indices ij both belong to active orbitals, and I0> is a CAS wave function. [Pg.253]

The cost of extending integral programs is usually far from small, if one wishes them to perform efficiently, and if the program does not perform efficiently then the time taken in the optimization program to evaluate the gradient elements can become prohibitive. [Pg.57]

The above method can be applied straightforwardly to calculate m dependent Cartesian forces (gradient elements) from 3Af — m independent... [Pg.232]

This expression is again written in an abbreviated form using the index permutation operators and Since the symmetric combination of Fock matrix elements is required for the Hessian matrix and the antisymmetric combination for the gradient elements, the matrix F itself may be explicitly constructed and then its contributions included into the other matrix elements as needed. Eq. (166) shows that a larger subset of two-electron integrals are required for the Hessian elements than for the computation of the gradient elements (two unoccupied orbital indices instead of just one), but for typical MCSCF wavefunctions and orbital basis sets this is still only a small fraction of the total. [Pg.114]

Severinghaus et al. (2001) directly observed thermal fractionation of the present-day fim air in response to seasonal temperature gradients. Elemental and isotopic ratios of N2, O2, Ar, Kr, and Xe analyzed in the air of the top 15 m of the fim at two Antarctic sites were found to match a model without adjustable parameters reasonably well. Relative thermal diffusion sensitivities for different gas pairs could be derived. [Pg.688]

Where, there has been used the commutative property of the diagonal matrices product. A total density function has been represented by the symbol T = Diag p K). Formally, the KE part, K, must be considered a diagonal matrix, where the components of the square gradient elements are located, for instance ... [Pg.43]

Since the definition of a stationary point requires that all gradient elements are zero, the closest stationary point can be found by minimizing the sum of squares of elements of the gradient vector. [Pg.46]

In such cases, it is implicit that the first gradient element is the derivative with respect to the first variable, etc. [Pg.515]

We call this line a gradient extremal (GE) [37, 38, 39, 40, 41, 42]. Unless the function increases indefinitely, the gradient element (i) must eventually become zero or approach zero. It is therefore reasonable to expect that by following a GE we sooner or later hit a new stationary point... [Pg.129]

It was shown [52, 53], that this method permits to optimize the technological conditions of gradient elements manufacture for any concrete application. [Pg.86]

Figure 4. Dependence of value of refractive index (1) and molar part of diffusant-1,1,3-trihydrotetrafluoropropilemethacrylate (4FMA) (2) on gradient element radius on the basis of matrix of silicon-organic dimethacrylate. Figure 4. Dependence of value of refractive index (1) and molar part of diffusant-1,1,3-trihydrotetrafluoropropilemethacrylate (4FMA) (2) on gradient element radius on the basis of matrix of silicon-organic dimethacrylate.
The gradient elements can be obtained by elaborate of modernized methods, which control the signs of both the exchange diffusion method, and layer by layer copolymerization method [12, 39, 60, 69, 70, 71]. In these methods the liquid monomer components - gradient-formers (individual substances or blends) with various values of refractive index are used. [Pg.87]

Generally, polarimetry requires the establishment of the type, quality, azimuth and ellipticity of the polarization. In addition, polarization of some type of irradiated or dispersed light [irradiated by natural and artificial objects or some of light-source] is difficult and it can contain simultaneously linear, elliptic, circular or partial polarized components [94]. The whole polarimetric analysis of such objects needs to investigate. At the same rime, appheation of the standard polarization optical elements, for the investigation of the polarization state of each section, it is necessary to take each complete set of different gradient elements, and for this reason it is difficult and labor-intensive to carry out such investigations. [Pg.104]

Nadareishvili L.I., Skhirtladze LA., Japaridze K.G. /The method for obtaining of gradient elements. I I Author certificate. No 1808733 (Rusian Federation) B29D11/00. Bull. No 2,1993 [In Russian]. [Pg.111]

According to the data from an interference picture, determination of the refractive index profile by cross-section of the gradient element consists of calculation of the function A =... [Pg.5]

Because any dielectric medium (including selfocs) possesses dispersion of the lefiuctive index, it is necessaiy to strive for gradient elements that produce low chromatic aberration. It is found that chromatic aberration depends on the relative optical characteristics of polymers of the matrix and diffusate separately and, consequently, proper selection of a pair of copolymers is the main factor determining low chromatic aberration [26]. [Pg.7]

Table 1. [72] Influence of change of DMEG concentration in the initial matrix on optical properties of gradient elements, Tpoiym = 75°C, [PB] = 0.75 mass. %... Table 1. [72] Influence of change of DMEG concentration in the initial matrix on optical properties of gradient elements, Tpoiym = 75°C, [PB] = 0.75 mass. %...

See other pages where Gradient elements is mentioned: [Pg.200]    [Pg.276]    [Pg.179]    [Pg.56]    [Pg.27]    [Pg.515]    [Pg.112]    [Pg.167]    [Pg.168]    [Pg.21]    [Pg.129]    [Pg.46]    [Pg.14]    [Pg.77]    [Pg.78]    [Pg.83]    [Pg.84]    [Pg.87]    [Pg.89]    [Pg.93]    [Pg.93]    [Pg.94]    [Pg.197]    [Pg.68]    [Pg.3200]    [Pg.117]    [Pg.106]    [Pg.3]    [Pg.4]    [Pg.5]    [Pg.6]    [Pg.8]    [Pg.9]   
See also in sourсe #XX -- [ Pg.77 , Pg.78 , Pg.83 , Pg.84 , Pg.86 , Pg.87 , Pg.89 , Pg.94 , Pg.104 , Pg.111 ]

See also in sourсe #XX -- [ Pg.3 , Pg.6 , Pg.7 , Pg.8 , Pg.9 , Pg.11 , Pg.19 , Pg.20 , Pg.22 , Pg.23 , Pg.25 , Pg.26 , Pg.27 , Pg.41 , Pg.49 ]




SEARCH



© 2024 chempedia.info