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Individuals, effect-related parameters

In contrast, the rate constants for methanol addition to the series of silicon-substituted silenes 2a-i (Table 13) do not vary in a straightforward way with either inductive io ) or resonance (o ) substituent parameters associated with the R substituent. However, a multi-parameter fit of the data to equation 64, in which Es is the steric substituent parameter of Unger and Hansch122 and p, pr and ps are the related standard reaction constants describing the individual effects of inductive, resonance and steric effects on the rate (and are the variables in the analysis), led to an excellent least-squares fit of the data (r2 = 0.965). This afforded the coefficients pr = —3.6 1.2, pi = 3.1 1.0 and ps = 0.21 0.08, where the quoted errors represent the 95% confidence limits of the analysis. Figure 11 shows a plot of the data against the function obtained from the least-squares fit (equation 65). [Pg.999]

The far better understanding of rescue consequences caused by the deterioration of functional features of materials is directly related to the practice of industrial applications and the durability studies accomplished on multipurpose products. The synergetic actions of various factors leads to the conclusion that the simple addition of individual effects is possible, if a predominant factor directs degradation of a specific way. One illustrative kinetic parameter that characterizes the diminution of certain property is half life, defined by Eq. (7) [32] ... [Pg.201]

In several cases, such as shellfish areas and aquatic reserves, the usual water quaUty parameters do not apply because they are nonspecific as to detrimental effects on aquatic life. Eor example, COD is an overall measure of organic content, but it does not differentiate between toxic and nontoxic organics. In these cases, a species diversity index has been employed as related to either free-floating or benthic organisms. The index indicates the overall condition to the aquatic environment. It is related to the number of species in the sample. The higher the species diversity index, the more productive the aquatic system. The species diversity index is computed by the equation K- = (S — 1)/logjg I, where S is the number of species and /the total number of individual organisms counted. [Pg.222]

The effect of water salinity on crop growth is largely of osmotic nature. Osmotic pressure is related to the total salt concentration rather than the concentration of individual ionic elements. Salinity is commonly expressed as the electric conductivity of the irrigation water. Salt concentration can be determined by Total Dissolved Solids (TDS) or by Electrical Conductivity (EC). Under a water scarcity condition, salt tolerance of agricultural crops will be the primordial parameter when the quality of irrigation water is implicated for the integrated water resources management [10]. [Pg.164]

In predicting the effects of a pollutant on population growth rate, the effects of the chemical on the values of t, I, and n are of central interest. Chemical residue data and biomarker assays that provide measures of toxic effects are relevant here because they can, in concept, be used to relate the effects of a chemical upon the individual organism to a population parameter such as survivorship or fecundity (Figures 4.5 and 4.6). Examples of this are discussed in the second part of the text, including the reduction of survivorship of sparrow hawks caused by dieldrin (Chapter 5), the... [Pg.92]

For a molecular ion with charge number Q a transformation between isotopic variants becomes complicated in that the g factors are related directly to the electric dipolar moment and irreducible quantities for only one particular isotopic variant taken as standard for this species these factors become partitioned into contributions for atomic centres A and B separately. For another isotopic variant the same parameters independent of mass are still applicable, but an extra term must be taken into account to obtain the g factor and electric dipolar moment of that variant [19]. The effective atomic mass of each isotopic variant other than that taken as standard includes another term [19]. In this way the relations between rotational and vibrational g factors and and its derivative, equations (9) and (10), are maintained as for neutral molecules. Apart from the qualification mentioned below, each of these formulae applies individually to each particular isotopic variant, but, because the electric dipolar moment, referred to the centre of molecular mass of each variant, varies from one cationic variant to another because the dipolar moment depends upon the origin of coordinates, the coefficients in the radial function apply rigorously to only the standard isotopic species for any isotopic variant the extra term is required to yield the correct value of either g factor from the value for that standard species [19]. [Pg.324]

In 10 there a great variety of materials is used, and their optical constants may be affected e.g. by film deposition technologies. What is thus required is the access to data for material dispersion with relation to technological parameter as well, either as Sellmeier or related formula, or as tabulated values. Additionally, refractive indices respond to temperature, which may be intended for device operation in case of a TO-switch, or unintended in field use. The temperature dependence of the refractive index can be attributed to the individual material, simply, but the influence of heater electrodes needs special consideration. If an 10 design-tool comes with inherent TO or EO capabilities, those effects are taken into account in the optical design directly. [Pg.269]


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See also in sourсe #XX -- [ Pg.55 ]




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Effective parameter

Effects parameters

Effects-related parameters

Individual effects

Related Parameters

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