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Computer direct-associative

In many cases the amount of solute associated with the leached sohd must not exceed a certain value, and it is possible to compute directly the minimum number of units needed by putting n = N. [Pg.89]

In the case of computer simulations of fluids with directional associative forces a less intuitive but computationally more convenient potential model has been used [14,16,106]. According to that model the attraction sites a and j3 on two different particles form a bond if the centers of reacting particles are within a given cut-off radius a and if the orientations of two spheres are constrained as follows i < 6 i and [tt - 2 < The interaction potential is... [Pg.194]

This hybrid approach can significantly extend the domain of applicability of the AIMS method. The use of interpolation significantly reduces the computational effort associated with the dynamics over most of the timescale of interest, while regions where the PESs are difficult to interpolate are treated by direct solution of the electronic Schrodinger equation during the dynamics. The applicability and accuracy of the method was tested using a triatomic model collisional quenching of Li(p) by H2 [125], which is discussed in Section III.A below. [Pg.471]

Computability of quantities that enable the extraction of properties specific for extended systems, such as density of states, bandwidths and gaps, and other spectral properties, i.e., response properties physically and conceptually most directly associated with experiments ... [Pg.37]

The first viewpoint defines the N-particle picture and leads in principle to an exact solution of Eq.(3). Leaving aside the question of whether or not one could extract useful information from the complicated form that such an exact solution for large values of N would be bound to take, the computational hindrance associated with this approach as N increases has mitigated against widespread use of such a direct procedure. At the same time, where it has been implemented[29], such as in connection with the He atom, this approach has yielded results which agree to great precision with those of exact numerical procedures. [Pg.89]

The hyperfine coupling associated with Line A is characteristic of an a-proton bonded to C2 with ir-spin density at the carbon. The fit between the direct cosine associated with Amin and the computed direction of C2-H is excellent, they differ... [Pg.506]

The third line seen in some of the ENDOR spectra was not as easy to analyze. It can be seen in Figure 18-7 that this line closely follows another stronger ENDOR line associated with Radical II. However enough data were available to determine that line C is to be associated with a small C8-H coupling. Again the fit between the expected direction and the computed direction of Amin is excellent (Table 18-1). [Pg.507]

It is important to note that the proportional relationship between Amax, Amid, and Amin for these couplings is the same for 100% spin density, and for the present case with approximately 50% spin density. When this is so it indicates that there is no rocking motion at the radical site. This is good evidence therefore that the radical site is essentially planar. The best evidence for radical planarity comes from the analysis of the direction cosines associated with each principal values of the hyperfine coupling tensor. The direction of Amin (Table 18-2) is known to be associated with the direction of the >C-H bond, while the direction associated with the Amid indicates the direction of the n-clcctron orbital. These directions are easily calculated from the crystal structure, and are included in Table 18-2. One sees that the direction associated with Amid deviates only 2.0° from the computed perpendicular to the ring plane, while the direction of Amin, deviates only 2.8° from the computed direction of the C6-H bond. The errors listed on these values are at the 95% confidence level. This is very clear evidence that the radical shown here is planar in the solid-state. Any torsional motion of the C6-H would lead to asymmetries of the hyperfine coupling tensor, and would not produce the observed agreement between the direction cosines and the known directions obtained from the crystal structure. [Pg.510]

The orientational contribution can be computed directly from the integrated line intensity of the absorption band associated with the dispersion by using the Kramers-Kronig relation in the form... [Pg.250]

The severe computational burden associated with assembling and carrying out adsorption calculations on disordered model microstructures for porous solids, such as those discussed in Sections ILA and II.B, has until recently limited the development of pore volume characterization methods in this direction. While the reahsm of these models is highly appealing, their application to experimental isotherm or scattering data for interpretation of adsorbent pore structure remains cumbersome due to the structural complexity of the models and the computational resources that must be brought to bear in their utilization. Consequently, approximate pore structure models, based upon simple pore shapes such as shts or cylinders, have been retained in popular use for pore volume characterization. [Pg.219]

The standard deviation of the PLS regression coefficients cannot be computed directly. To overcome this problem. Centner proposed to use leave-one-out and to define stability of the b coefficient associated with the ith variable as ... [Pg.328]

Some problems encountered with the various detectors for radionuclide measurements have generic aspects related to ambient conditions, detector and ancillary equipment functions, computer operation, and the operator. Other problems are directly associated with the type of detector, its ancillary equipment, and its functions. [Pg.256]

This illustrates the principles of the calculation. In practice, this calculation is easily made using a statistical pocket calculator or using dedicated computer software associated with kits for direct analysis of data. [Pg.358]

In the scenario of transformable manufacturing structures, the focus will no longer be on the computer-directed factory without man of the 1980s but on the accomplishment of factory structures that employ of the latest technology. Human beings, with their unique power for associative and creative thinking, will then take a crucial part in guaranteeing the continuous adaptation of factory structures. [Pg.2887]

Perluqrs more imptvtantly, note that the basic approach developed here may be tqrplied equally well to a system of chains which have internal closed loops. Of course, the computation of all vectors and matrices directly associated with the chains, such as the opra-chain acceleration t ms, (qi)open and (xk)optn, the inverse opoational space inertia matrix, and the coefficient matrix, Slk, would require extended algorithms to account for the more complex chain structure. [Pg.121]


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See also in sourсe #XX -- [ Pg.193 ]




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