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Diffusion Directed search

While this maybe true for the reaction in 4.7.2., l.e. - Mi2+ <. Xj, what of the case for BaSiOs where diffusion was limited to one direction It is not reasonable to assume that the solid would build up a cheirge as the Mj2+ ions are diffusing (and the Si04= ions are not) and we must search for compensating species elsewhere. It turns out that charge compensation occurs by diffusion of chained vacancies in the lattice. [Pg.152]

The residual difference after a successful DDM refinement or/and decomposition can be considered as a scattering component of the powder pattern free of Bragg diffraction. The separation of this component would facilitate the analysis of the amorphous fraction of the sample, the radial distribution function of the non-crystalline scatterers, the thermal diffuse scattering properties and other non-Bragg features of powder patterns. The background-independent profile treatment can be especially desirable in quantitative phase analysis when amorphous admixtures must be accounted for. Further extensions of DDM may involve Bayesian probability theory, which has been utilized efficiently in background estimation procedures and Rietveld refinement in the presence of impurities.DDM will also be useful at the initial steps of powder diffraction structure determination when the structure model is absent and the background line cannot be determined correctly. The direct space search methods of structure solution, in particular, may efficiently utilize DDM. [Pg.295]

Among many techniques used to obtain skeletons of larger mechanisms, in what follows we discuss the Direct Relation Graph (DRG) technique, coupled with Depth First Search (DFS) technique, the Sensitivity Analysis of the Jacobian matrix for the chemical system, the Intrinsic Low-Dimensional Manifold (ILDM) technique, the Reaction Diffusion Manifolds (REDIM technique) and the flamelet technique. Among these, the flamelet technique is preferred for writing the simplified chemical system for premixed flames and diffusion flames presented in the following sections. [Pg.73]

When an oscillating reaction-diffusion system is near a direct Hopf bifurcation, the dynamics may be described by the CGL Equation (1). The analytic study of spiral waves in the framework of the CGL equation has been carried out by Hagan [8]. This author searched for solutions of Equation (1) by considering the following ansatz ... [Pg.195]


See other pages where Diffusion Directed search is mentioned: [Pg.148]    [Pg.119]    [Pg.295]    [Pg.208]    [Pg.626]    [Pg.184]    [Pg.288]    [Pg.194]    [Pg.80]    [Pg.211]    [Pg.223]    [Pg.42]    [Pg.275]    [Pg.1273]    [Pg.241]    [Pg.120]    [Pg.925]    [Pg.457]    [Pg.395]    [Pg.251]    [Pg.860]    [Pg.646]    [Pg.264]    [Pg.94]    [Pg.173]    [Pg.189]    [Pg.169]    [Pg.34]    [Pg.48]    [Pg.47]    [Pg.370]    [Pg.278]    [Pg.544]    [Pg.40]    [Pg.231]    [Pg.456]    [Pg.151]    [Pg.26]    [Pg.1355]    [Pg.454]    [Pg.119]    [Pg.182]    [Pg.251]    [Pg.1542]    [Pg.265]    [Pg.607]   
See also in sourсe #XX -- [ Pg.140 ]

See also in sourсe #XX -- [ Pg.140 ]




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