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Higher Differences

Differencing is an operation on a sequence which gives another sequence. We can therefore apply it again to that result sequence. This gives the sequence of second differences. 5(5V) is naturally denoted by 52V, and 52 is called the second difference operator. If we use the central difference convention [Pg.7]


Higher differences for the interaction of both the biological and the synthetic receptors with the two enantiomers are found for the propanol-derivatives than for the ethanol-derivatives (Norephedrine, Metaraminol vs. Octopamime, Noradenaline Pseudoephedrine, Ephe-drine vs. Synephrine, Adrenaline). [Pg.355]

According to fhe calculated minimum energy of fhe conformers, the GA was more stable than the AA conformer, but at 298.15 K the Gibbs energy of the AA conformer was 0.168 kj moU less than that of the GA conformer, indicating 52% of AA versus 48% of GA or almost equal amounts of the two conformers at equilibrium at room temperature [46]. A higher difference... [Pg.321]

In the case of the hydrogen isotopes the effect can be a very serious limitation on their usefulness as tracers since rate differences up to tenfold have been observed for deuterium and of course much higher differences are possible for tritium. There will be some indication of how this limitation operates in the final section of this review. [Pg.131]

Li+, and Na+, the four ionophores showed higher differences in selectivity than for the larger ions K+ and Rb+ as well as for alkaline earth metal ions. Better results than those previously reported with other ligands in terms of detection limits (5 x 10 7) and log/i (4.46) were found for the l,3-diisopropoxycalix[4]arene-crown-6 in the 1,3-alternate conformation.77... [Pg.225]

The differences in temperature measured in the centre of a droplet and the temperature of its atmosphere are shown in Table 1 for three solvents. Higher differences were seen for the droplets that were placed upon the insulating substrates. [Pg.62]

The key fact on which we build a theory is that if (and only if) polygon vertices are samples at equal intervals from a polynomial of degree at most d, then the d + 1th differences (and all higher differences) of the polygon are zero. [Pg.119]

Here the lower summation limit A Dmin = ( o -ex)/5 = 6 - i o is the activation barrier of formation of the complex N20 ( i +) without changing vibrational quantum number V (see Fig. 6-7) and ex is the kinetic energy of the relative O-N2 motion. The Landau-Zener factors don t change a lot with Ad, whereas the Frank-Condon factors abruptly decrease at higher differences A d in vibrational quantum numbers during transition. Summation (6-21) gives the formation probability of N20 ( i +) ... [Pg.365]

The DFT values of four radicals deviate reasonably by less than 1 kcal moF from the GA values. The remaining twelve eight radicals given in Table 7.2 show higher differences between DFT and GA calculations. In all eight cases we can not explain this deviation at this moment and a review of our GA parameters has to be done. [Pg.129]

With respect to the exactness of copying the shape of a compound the question arises as to whether these polymers are able to resolve racemates other than that of the template. Polymers were prepared from different esters of glyceric acid phenyIboronate (Sa, 5b, 5c (46)). Table IV shows the selectivity of the polymeri for resolution of different racemates. The polymers were most specific for resolution of the racemate of their own templates. Small differences in structure led to a decrease in specificity higher differences resulted in a complete disappearence of specificity. Similar results were obtained in other cases (47,60). [Pg.202]

Hydrophilic membranes have a higher difference in the flow due to pure solvent polarity when compared with hydro-phobic membranes. According to Bhannshali et al. [22], the permeation of pure solvents in hydrophilic membrane (composed of aromatic PA) shows that polar solvents (methanol, ethanol, and isopropanol) have significantly higher flow (8-10 times) than nonpolar solvents (pentane, hexane, and octane). In contrast, the flow of nonpolar solvents was two to four times greater than the flow of polar solvents on hydro-phobic membranes (consisting of dimethyl silicone). [Pg.644]

There are few differences in the setting time in the world standards initial setting time is in the range 40-90 min, the final is 6, 8, and 10 or 12 h. Much higher differences are embracing special cements beyond the standards (see Chap. 8). In EN 197-1 standard there is even no requirement for final setting time. This approach is,... [Pg.11]


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