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INDEX contribution

Where waters have a stabiHty index of 6.0 or less, scaling increases and the tendency to corrode decreases. Where the stabiHty index exceeds 7.0, scaling may not occur at all. As the stabihty index rises above 7.5 or 8.0, the probabiHty of corrosion increases. Use of the LSI together with the Stabihty Index contributes to more accurate prediction of the scaling or corrosive tendencies of a water. [Pg.269]

If one takes a finite upper bound for the computer time requirement for each fragment density matrix, as well as for its share of nonzero index contribution to the final, macromolecular density matrix, then one can show that the computer time requirement of the ADMA computation grows linearly with the number of fragment density matrices. [Pg.214]

To derive the right-hand side of Equations (52), (28) and Table 12.1 were used. Note that the texture index contributes not only to the refined coefficients but also the coefficients linearly correlated from the cubic groups and also... [Pg.347]

In combining QSPR with nonlinear optimization to perform the reverse engineering design of polymers with optimal balances of properties, Camarda and Maranas [14] adopted an approach based on the work described in this book and combined group contributions with connectivity index contributions to predict the properties. [Pg.659]

As before, the scaling transform is defined by S (a, b) = Z7o(a, b). FVom the definition of the scaling transform we have d S (a = oo,b) = 0, for all b. FVom the asymptotic expansion above, we also have d S (a = 0,6) = 0. Therefore, —dnS (a. 6) must have local extrema, in the scale variable, for any 6. As noted earlier, this expression also corresponds to the subtotal of all wavelet terms, in the translation variable index, contributing to (6) at scale value a. [Pg.239]

In transmission measurements, the major contribution is the absorptive index and the refractive index contribution is small. In reflection, the major contributor is the refractive index. [Pg.86]

Tests on vehicles have shown that the volatility index as defined expresses satisfactorily the fuel contribution during hot operation of the engine (Le Breton, 1984). In France, specifications stipulate that its value be limited to 900, 1000 and 1150, respectively, according to the season (summer, spring/fall, winter). The automobile manufacturers, being even more demanding, require in their own specifications that the FVI not be exceeded by 850 in summer. [Pg.191]

Multichannel time-resolved spectral data are best analysed in a global fashion using nonlinear least squares algoritlims, e.g., a simplex search, to fit multiple first order processes to all wavelengtli data simultaneously. The goal in tliis case is to find tire time-dependent spectral contributions of all reactant, intennediate and final product species present. In matrix fonn tliis is A(X, t) = BC, where A is tire data matrix, rows indexed by wavelengtli and columns by time, B contains spectra as columns and C contains time-dependent concentrations of all species arranged in rows. [Pg.2967]

Fundamental Limitations to Beers Law Beer s law is a limiting law that is valid only for low concentrations of analyte. There are two contributions to this fundamental limitation to Beer s law. At higher concentrations the individual particles of analyte no longer behave independently of one another. The resulting interaction between particles of analyte may change the value of 8. A second contribution is that the absorptivity, a, and molar absorptivity, 8, depend on the sample s refractive index. Since the refractive index varies with the analyte s concentration, the values of a and 8 will change. For sufficiently low concentrations of analyte, the refractive index remains essentially constant, and the calibration curve is linear. [Pg.386]

We desire to use the probability function derived above, so we recognize that the mass contribution of the volume element located a distance r from an axis through the center of mass is the product of the mass of a chain unit mp times the probability of a chain unit at that location as given by Eq. (1.44). For this purpose, however, it is not the distance from the chain end that matters but, rather, the distance from the center of mass. Therefore we temporarily identify the jth repeat unit as the center of mass and use the index k to count outward toward the chain ends from j. On this basis, Eq. (1.49) may be written as... [Pg.53]

When exposed to fire. Teflon PEA contributes Httle in fuel value and is self-extinguishing when the flame is removed. The fuel value is approximately 5.4 MJ/kg (2324 Btu/lb). It passes the UL 83 vertical-flame test and is classified as 94VE-0 according to UL 94. The limiting oxygen index (LOI) by ASTM D2863 is above 95%. [Pg.375]

Elame-spread and smoke-density values, and the less often reported fuel-contributed semiquantitive results of the ASTM E84 test and the limited oxygen index (LOI) laboratory test, are more often used to compare fire performance of ceUular plastics. AH building codes requite that ceUular plastics be protected by inner or outer sheathings or be housed in systems aH with a specified minimum total fire resistance. Absolute incombustibHity cannot be attained in practice and often is not requited. The system approach to protecting the more combustible materials affords adequate safety in the buildings by aHowing the occupant sufficient time to evacuate before combustion of the protected ceUular plastic. [Pg.336]

Correlation methods discussed include basic mathematical and numerical techniques, and approaches based on reference substances, empirical equations, nomographs, group contributions, linear solvation energy relationships, molecular connectivity indexes, and graph theory. Chemical data correlation foundations in classical, molecular, and statistical thermodynamics are introduced. [Pg.232]

Pure, low temperature organic Hquid viscosities can be estimated by a group contribution method (7) and a method combining aspects of group contribution and coimectivity indexes theories (222). Caution is recommended in the use of these methods because the calculated absolute errors are as high as 100% for individual species in a 150-compound, 10-family test set (223). A new method based on a second-order fit of Benson-type groups with numerous steric correctors is suggested as an alternative. Lower errors are claimed for the same test set. [Pg.253]


See other pages where INDEX contribution is mentioned: [Pg.179]    [Pg.531]    [Pg.179]    [Pg.251]    [Pg.289]    [Pg.214]    [Pg.179]    [Pg.219]    [Pg.374]    [Pg.314]    [Pg.515]    [Pg.179]    [Pg.531]    [Pg.179]    [Pg.251]    [Pg.289]    [Pg.214]    [Pg.179]    [Pg.219]    [Pg.374]    [Pg.314]    [Pg.515]    [Pg.403]    [Pg.3018]    [Pg.433]    [Pg.224]    [Pg.552]    [Pg.693]    [Pg.728]    [Pg.191]    [Pg.371]    [Pg.85]    [Pg.193]    [Pg.34]    [Pg.116]    [Pg.372]    [Pg.541]    [Pg.9]    [Pg.10]    [Pg.530]    [Pg.326]    [Pg.109]    [Pg.122]    [Pg.332]    [Pg.332]    [Pg.337]    [Pg.481]   
See also in sourсe #XX -- [ Pg.176 ]




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