Examination of the right-hand ordinate of Fig. 5.2 shows that the data presented there represent only about the last 20% of the range of p values. The zero of the time scale has thus been shifted to pick up the analysis of the reaction at this point. [Pg.287]

When r) values are plotted against the g values, Hammett s equation is satisfied for all the substituents except for bromine and iodine, as shown in Figure 12.2. The p value is 4.8, which is within the range of p values reported for a variety of substituted reactions such as nitration, bromination, and hydrolysis (Stock and Brown, 1956). Therefore, Hammett s equation for substituted benzenes reaction with e can be expressed as ... [Pg.493]

Quantum-mechanical calculations (Grozema et al. 1999, 2000 Berlin et al. 2000) that take the molecular wire and quantum mechanical channels (cf. Fig. 12.14) into account are capable of explaining the wide range of P values reported. This theory also allows for the observed drastic dependence on the rate of hole transfer on the number and nature of the nucleotide pairs AT vs GC between the donor (G +) and the acceptor (GGG) as reported by Meggers et al. [Pg.421]

The nature of the relationship between P and drug activity depends on the range of P values obtained for the compounds used. If this range is small the results may be expressed as a straight line equation having the general form ... [Pg.80]

Ranges of

[Pg.20]

There are many different ways in which the acid dyes are applied, the variations being designed, in the main, to create conditions giving liquors with a range of p values to suit the type of dye. [Pg.390]

The elimination in wastewater treatment plants can be characterized by the range of P values as given in 22.2.1.2 (textile dyes), although paper dyes should be placed on the upper end of the range due to the larger molecular sizes. [Pg.338]

Figure 18.1 Distribution of a one-sided P-value given as a function of power given a nominal size of 0.025. (The range of P-values illustrated is restricted to 0.1 or less in order to prodnce a... |

Over a limited range of (p values, the relationship between the retention factor and

[Pg.223]

Figure 2.3 shows the utility and limits of this approximation method. Here, four aromatic hydrocarbons are eluted on a Cig column. Mobile phases were prepared so that the elution profiles were as closely matched as possible. Calculation of P values give the following results 50/50 water/2-methoxyethanol, P = 7.85 65/35 water/ IPA, P = 8.00 56/44 water/acetonitrile, P = 8.26 71/29 water/n-propyl alcohol, P = 8.40 62/38 water/THF, P = 7.84. (Note the refiactive index peak/trough just after the injection of the sample on the water/THF solvent system. This effect is not present on any other chromatogram). From the ranges of P values obtained, 7.84-8.40, it is evident that the use of this parameter will generate approximate conditions only. [Pg.51]

Phase separation into two phases (p and (p occurs if the stability criterion / (cp) > 0 is not satisfied for all values of f. In that case, there is a range of

second derivative of the free energy of mixing density is negative. This implies a schematic behavior for Afm

[Pg.291]

The second approach uses judgment standards to evaluate P factors. For example, the P factor is increased if two generators are placed in the same room or maintained by the same worker. A relatively complete set of standards was proposed by Humphreys (Humphreys 1987) and adopted by Atomic Energy Authority (AEA) (Brand 1996). Generally this approach provides ranges of p values, but the final choice is subjectively done by analyzers. [Pg.1422]

The same authors have given a curve showing variation of maxima in terms of p for fixed values of D (and for the same values of spacing). It may be observed that some peaks, generally intense, are almost Independent of D and markedly influenced by / , while other ones, whose importance is fairly limited to the central range of p values, are essentially functions of D. [Pg.275]

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