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Properties value distribution

Fields as property values in 3-D space can either be evaluated and encoded on a regular (often cubic) grid [71], or approximated by certain distribution functions. Most often, Gaussians [83] have been employed here, as they have some desirable mathematical properties and can usually approximate the original field reasonably well with not too many parameters. [Pg.84]

Shape descriptor derived from the second derivative of the electronic energy distribution with 2 meaning the shorter length rays are represented and 4 meaning that intermediate property values are represented. [Pg.422]

Figs. 4.63 - 4.66 illustrate the location of lines of constant values of temperature, degree of conversion, velocity and viscosity for five consecutive positions of the front of a stream, which correspond to the following values of the axial coordinate xf 0.2, 0.4, 0.6, 0.8, and 1.0. These lines of constant values of the process variables are calculated for the flow and property values designated by the point D in Fig. 4.61. In this case, the mold temperature Tm = 70°C, the initial temperature of the reactive mix To = 40°C, and the initial temperature of the insert Ti = 20°C. An area above the horizontal line of symmetry of the mold cavity (i.e., the upper part of the cavity) contacts the "hot" surface of the mold and the lower part is in contact with the surface of the cooler metal insert. Thus, we can conclude that the distributions of temperature, degree of conversion, viscosity and velocity of movement of the reactive mix along the mold are related to the ratios between the transfer rate and the chemical reaction, which are characterized by the values of the Da and Gz Numbers. [Pg.213]

Both the g-value distribution and the hyperfine splittings of the g = 2.0055 defect are consistent with the expected properties of dangling bonds. Consistency, however, does not constitute proof of the structure, and other possibilities have been proposed, which are discussed below. The ESR parameters do provide quantitative constraints that must be met by alternative models and, at present, are the only specific experimental information that we have about the defect wavefunctions. [Pg.111]

This method uses the high-performance liquid chromatography (HPLC) equipment for sample handhng and requires molar mass sensitive detectors (such as light scattering and/or viscometry) to obtain a mean property values from each detector (Mw and/or IV, respectively). The FIA result from a concentration detector yields polymer content in a sample, which can also be determined with other well-established methods. The FIA approach requires expensive and well-maintained equipment, and will not save much time or solvent furthermore, no distribution information is available. [Pg.781]

The properties which determine heat transfer through a deposit layer of given thickness are thermal conductivity, emissivity, and absorptivity. These properties vary with deposit temperature, thermal history, and chemical composition. Parametric studies and calculations for existing boilers were carried out to show the sensitivity of overall furnace performance, local temperature, and heat flux distributions to these properties in large p.f. fired furnaces. The property values used cover the range of recent experimental studies. Calculations for actual boilers were carried out with a comprehensive 3-D Monte Carlo type heat transfer model. Some predictions are compared to full-scale boiler measurements. The calculations show that the effective conduction coefficient (k/As)eff of wall deposits strongly influences furnace exit temperatures. [Pg.375]

Most of the methods that are used to predict logP values of molecules depend on fragmental codes or lipophilicity increments based on extended atom types. Obviously, it is possible to assign lipophilicity increments directly to every atom of a structure as an atomic property. The distribution of lipophilic and hydrophilic properties in a molecule can be described in this way [53]. [Pg.577]

The property values on the membrane surface and in the film at the interface are considered at equilibrium, related to each other by equilibrium distribution coefficients, assumed equal on both sides of the membrane ... [Pg.600]

First, a number of points are randomly distributed on the molecular surface with a user-defined density and in an orderly manner to ensure a continuous surface. Then, the Surface Autocorrelation Vector (SAV) is derived by calculating for each lag k the sum of the products of the property values at two surface points located at a distance falling into the kth distance interval. This value is then normalized by the number of the geometrical distances r,j in the interval ... [Pg.36]

Then, distributions for the occurrences of the various molecular properties in two sets of molecules, one of active molecules and the other of inactive molecules, are evaluated. From these frequency distributions, weights are calculated using one of the two weighting schemes, each of which seeks to quantify the differential occurrences of the defined ranges of property values in active (AC) and inactive (IN) molecules ... [Pg.669]

PEST Autocorrelation Descriptors (or PAD descriptors) are spatial autocorrelation descriptors defined on the basis of TAE and PEST descriptors [Breneman, Bundling et al., 2003]. For each ray in PEST, the length of the ray and the product of the property values at starting and ending points are computed. The distribution is birmed into 20 bins along the ray length and the autocorrelation values for each bin calculated. For 10 TA E properties, this yields a total of 200 PEST autocorrelation descriptors. [Pg.800]

On average, the correct shape of the Voronoi cell is spherical. Thus, the correct overall material model for the assumption of a random distribution is a collection of spherical cells of different sizes, each containing a single sphere. Strictly speaking, any overall property of the material should be obtained by summing the contributions from the different cell sizes. This summing may be carried out by application of a dispersion factor to the property value found for the cell describing the overall volume fraction (12). The results presented here were obtained for the cells that describe the overall volume fraction. The application of the spatial statistical model to take into account the effect of the variable cell size is the subject of current work. [Pg.15]

The specific properties studied here include charge distributions, energies, geometric structures and conformations, dipole moments, isomerization energies, bond dissociation energies, proton affinities, electron affinities, ionization potentials and spin populations, as well as the general trends in these and other properties, such as hypervalency character, and their underlying electronic structure causes. The comparison of calculated with experimental property values affords an opportunity to evaluate the computational methods. [Pg.2]


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See also in sourсe #XX -- [ Pg.345 ]




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