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Qualitative features

The one-dimensional cases discussed above illustrate many of die qualitative features of quantum mechanics, and their relative simplicity makes them quite easy to study. Motion in more than one dimension and (especially) that of more than one particle is considerably more complicated, but many of the general features of these systems can be understood from simple considerations. Wliile one relatively connnon feature of multidimensional problems in quantum mechanics is degeneracy, it turns out that the ground state must be non-degenerate. To prove this, simply assume the opposite to be true, i.e. [Pg.20]

In the following development we consider a plane wave of infinite lateral extent traveling in the positive Xj direction (the wave front itself lies in the Xj, Xj plane). When discussing anisotropic materials we restrict discussion to those propagation directions which produce longitudinal particle motion only i.e., if u is the particle velocity, then Uj = Uj = 0. The <100>, <110>, and <111 > direction in cubic crystals have this property, for example. The derivations presented here are heuristic with emphasis on the essential qualitative features of plastic flow. References are provided for those interested in proper quantitative features of crystal anisotropy and nonlinear thermoelasticity. [Pg.222]

Later on Cahn and Hilliard presented some thermodynamic estimates for the nucleation of liquid in vapour. Values of AO and the composition profiles c(r) of the embryos have been estimated using the mean-field and gradient expansion approximations for the free energy functional F c(7 ). A number of qualitative features in variation... [Pg.111]

Although specific calculations for i and g are not made until Sect. 3.5 onwards, the mere postulate of nucleation controlled growth predicts certain qualitative features of behaviour, which we now investigate further. First the effect of the concentration of the polymer in solution is addressed - apparently the theory above fails to predict the observed concentration dependence. Several modifications of the model allow agreement to be reached. There should also be some effect of the crystal size on the observed growth rates because of the factor L in Eq. (3.17). This size dependence is not seen and we discuss the validity of the explanations to account for this defect. Next we look at twin crystals and any implications that their behaviour contain for the applicability of nucleation theories. Finally we briefly discuss the role of fluctuations in the spreading process which, as mentioned above, are neglected by the present treatment. [Pg.247]

The results for e/fcTj, = 1.8 are shown in Fig. 4.7. Again, their importance lies in the correct qualitative features for polymer growth. However, it has recently been demonstrated that even with this simple model a fit of experimental growth rate and thickness data (of the polymer PEEK) can be achieved [166],... [Pg.300]

Decomposition of the metal ammines have probably been most extensively investigated. Some qualitative features of the thermal decomposition of metal ammine compounds are conveniently illustrated [1116— 1118] by the somewhat contrasting behaviour of the compounds [Cr(NH3)6]X3 and [Co(NH3)6]X3 where X is Cl- or Br . During decomposition of the chromium compound, the oxidation number of the metal remains unchanged, viz. [Pg.232]

Kaptein (1971a, b, 1972a) has further derived relations for predictmg net and multiplet effects on the basis of (i)-(iv) above. The qualitative features of CIDNP spectra can be determined by determining the signs of the functions Dub and Fme given by equation (39a) and (39b) for net and multiplet effects respectively. [Pg.74]

The key to understanding the titrations of weak acids and bases is to be familiar with the species in solution and the dominant equilibrium at each point along the titration curve. Example reinforces these qualitative features. [Pg.1298]

What the overall physiological consequences of either an increase or decrease in 5-HT transmission in any brain region might be is beyond the scope of this chapter. However, it is certain that the diverse cocktail of 5-HT receptors in every brain region gives scope for flexibility and refinement in the 5-HT response that would not be possible if there were only the two receptors identified by Gaddum. This flexibility applies not only to the qualitative features of the response but also its duration. Another dimension of sophistication is added by the different affinities of 5-HT for each of its receptors and differences in their rates of desensitisation. An interesting discussion of how all these variables could affect overall 5-HT transmission in the brain can be found in Uphouse (1997). [Pg.204]

A comparison of the qualitative features of the FRC spectra for the catalyst studied show a clear distinction between Rh/S102 and Rh/T102, In terms of their reversible H2-chemlsorptlon. Suprlslngly, little difference was observed between normal and SMSI-Rh/T102. "Normal" Rh/T102 behaved quite differently from Rh/S102, In spite of their similarities In total, l.e., static, chemisorption behavior. [Pg.72]

So far, the discussion of the dynamics and the associated phase-space geometry has been restricted to the linearized Hamiltonian in eq. (5). However, in practice the linearization will rarely be sufficiently accurate to describe the reaction dynamics. We must then generalize the discussion to arbitrary nonlinear Hamiltonians in the vicinity of the saddle point. Fortunately, general theorems of invariant manifold theory [88] ensure that the qualitative features of the dynamics are the same as in the linear approximation for every energy not too high above the energy of the saddle point, there will be a NHIM with its associated stable and unstable manifolds that act as separatrices between reactive and nonreactive trajectories in precisely the manner that was described for the harmonic approximation. [Pg.200]

The MaxEnt deformation density in the COO- plane is shown in Figure 6(a). The deformation map shows correct qualitative features differences between the single C-C bond and the C-0 bonds are clearly visible, and so are the lone-pair maxima on the oxygen atoms. If compared to the conventional dynamic deformation density... [Pg.30]

Before doing any formal analysis, we state a few qualitative features of each type of controller. This is one advantage of classical control. We can make fairly easy physical interpretation of the control algorithm. The analyses that come later will confirm these qualitative observations. [Pg.84]

There are hand-plotting techniques, but we ll rely on the computer. Still, we need to know the qualitative features of the plot resulting from several simple transfer functions. [Pg.147]

This section has treated the qualitative features of chemisorption and physical adsorption processes. Both are important to the chemical... [Pg.172]

A brief review is given of the important qualitative features of thermoplastic elastomers. Particular emphasis is given to the molecular structure, bulk morphology and interfacial character of these materials. Both equilibrium and nonequilibrium structures are discussed... [Pg.484]

Fig. 11. Qualitative features of the aid potential energy surface for tetramethylene. Black dots indicate roughly the positions of the minima, with relative energies as shown (eV). G stands for gauche ,... Fig. 11. Qualitative features of the aid potential energy surface for tetramethylene. Black dots indicate roughly the positions of the minima, with relative energies as shown (eV). G stands for gauche ,...
Busscher N, Kahl J, Huber M, Andersen J O, Mergardt G, Doesburg P, Paulsen M, Kretschmer S, de Weerd A and Meier-Ploeger A (2004), Validation and Standardization of the Biocrystallization Method Development of a Complementary Test to Assess Qualitative Features of Agricultural and Food Products, Triangle report Nr. 1, University Kassel, Louis Bolk Instituut and Biodynamic Research Association Denmark. [Pg.72]

Scattering of secondary electrons has been ignored in this calculation. Later, it was included by Chatterjee et al. (1973) on an approximate diffusional basis for electron energies below about 1600 eV However, the qualitative features of Figure 3.13 were retained. [Pg.65]

Forster (1959) classifies the qualitative features based on which one can distinguish the various modes of energy transfer. Mainly, only collisional transfer depends on solvent viscosity (vide infra), whereas complexing between the donor and acceptor changes the absorption spectrum. On the other hand, the sensitizer lifetime decreases for the long-range resonant transfer process, whereas it should be unchanged for the trivial process. [Pg.84]


See other pages where Qualitative features is mentioned: [Pg.133]    [Pg.16]    [Pg.16]    [Pg.20]    [Pg.23]    [Pg.25]    [Pg.35]    [Pg.36]    [Pg.2376]    [Pg.2385]    [Pg.200]    [Pg.565]    [Pg.782]    [Pg.130]    [Pg.664]    [Pg.21]    [Pg.390]    [Pg.703]    [Pg.1298]    [Pg.261]    [Pg.205]    [Pg.559]    [Pg.541]    [Pg.195]    [Pg.84]    [Pg.85]    [Pg.87]    [Pg.209]    [Pg.134]    [Pg.271]    [Pg.369]   
See also in sourсe #XX -- [ Pg.69 ]




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