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Magnitude three-dimensional

One technique for high dimensional data is to reduce the number of dimensions being plotted. For example, one slice of a three-dimensional data set can be plotted with a two-dimensional technique. Another example is plotting the magnitude of vectors rather than the vectors themselves. [Pg.118]

Laminar flame instabilities are dominated by diffusional effects that can only be of importance in flows with a low turbulence intensity, where molecular transport is of the same order of magnitude as turbulent transport (28). Flame instabilities do not appear to be capable of generating turbulence. They result in the growth of certain disturbances, leading to orderly three-dimensional stmctures which, though complex, are steady (1,2,8,9). [Pg.518]

The kinetic observations reported by Young [721] for the same reaction show points of difference, though the mechanistic implications of these are not developed. The initial limited ( 2%) deceleratory process, which fitted the first-order equation with E = 121 kJ mole-1, is (again) attributed to the breakdown of superficial impurities and this precedes, indeed defers, the onset of the main reaction. The subsequent acceleratory process is well described by the cubic law [eqn. (2), n = 3], with E = 233 kJ mole-1, attributed to the initial formation of a constant number of lead nuclei (i.e. instantaneous nucleation) followed by three-dimensional growth (P = 0, X = 3). Deviations from strict obedience to the power law (n = 3) are attributed to an increase in the effective number of nuclei with reaction temperature, so that the magnitude of E for the interface process was 209 kJ mole-1. [Pg.164]

The aniline-zinc porphyrin interaction has also been exploited to form dimers. Hunter (60) reported the dimerization of porphyrins functionalized at one meso position with ortho or meta aniline groups (47, 48, Fig. 15). Both compounds showed concentration-dependent H NMR spectra with large upfield shifts for the aniline protons. The dimerization constants are 160 and 1080 M-1 respectively for 47 and 48, and these values are an order of magnitude higher than the association constants of simple reference complexes (K — 10 and 130 M 1 respectively), which is indicative of cooperative self-assembly. The complexa-tion-induced changes in chemical shift were used to obtain three-dimensional structures of the dimers. [Pg.235]

Figure 31 shows the Tsp dependences of log Ks(max) and ED pattern of the monolayer prepared by the process mentioned above. This monolayer preparation corresponds to the case without a quench effect, because the amorphous monolayer was slowly cooled down to the temperature of 283 K. The ED pattern at 283 K exhibited a crystalline triclinic spot which was apparently different from the ED pattern of an amorphous halo, as shown in Figure 30. The magnitude of log Ksf, ) started to decrease apparently at ca. 300 K without any expression of the maximum log K max). Since the ED patterns at 298 and 303 K were a crystalline triclinic spot and an amorphous halo, respectively, Tm of lithium 10,12-heptacosadiynoate monolayer on the water surface was evaluated to be around 300 K. Tm of the monolayer on the water surface is much lower than that of three-dimensional crystal of 10,12-heptacosadiynoic acid (Tm=342 K). This is reasonable, because the monolayer is thermodynamically less stable than its three-dimensional crystal. Figure 31 shows the Tsp dependences of log Ks(max) and ED pattern of the monolayer prepared by the process mentioned above. This monolayer preparation corresponds to the case without a quench effect, because the amorphous monolayer was slowly cooled down to the temperature of 283 K. The ED pattern at 283 K exhibited a crystalline triclinic spot which was apparently different from the ED pattern of an amorphous halo, as shown in Figure 30. The magnitude of log Ksf, ) started to decrease apparently at ca. 300 K without any expression of the maximum log K max). Since the ED patterns at 298 and 303 K were a crystalline triclinic spot and an amorphous halo, respectively, Tm of lithium 10,12-heptacosadiynoate monolayer on the water surface was evaluated to be around 300 K. Tm of the monolayer on the water surface is much lower than that of three-dimensional crystal of 10,12-heptacosadiynoic acid (Tm=342 K). This is reasonable, because the monolayer is thermodynamically less stable than its three-dimensional crystal.
Three-dimensional (3-D) descriptors of molecules quantify their shape, size, and other structural characteristics which arise out of the 3-D disposition and orientation of atoms and functional groups of molecules in space. A special class of 3-D indices is quantitative descriptors of chirality. If a molecule has one or more chiral centers, the spatial disposition of atoms can produce enantiomers, many of which will have the same magnitude of calculated and experimental physicochemical properties having, at the same time, distinct bioactivity profiles. Basak and coworkers [22] have developed quantitative chirality indices to discriminate such isomers according to their structural invariants which are based on the Cahn-Ingold-Prelog (CIP) rules. [Pg.481]

The study of Lehn s cryptands has shown that a three-dimensional arrangement of binding sites leads to very stable inclusion complexes (cryptates) with many cations. For example, the stability constant for K+ in methanol/water (95/5) is five orders of magnitude higher with [2.2.2]-cryptand [37] (log K 9.75 Lehn and Sauvage, 1975) than with [2.2]-cryptand [38] (log... [Pg.290]


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See also in sourсe #XX -- [ Pg.38 ]

See also in sourсe #XX -- [ Pg.38 ]




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