Structural-growth parameter definition

At low coverages, most metallic adsorbates form ordered overlayers with a (1 x 1) surface structure on metal substrates. This implies that the substrate acts as a template and has a significant influence on the growth mode of the deposited material. This effect is usually called epitaxial growth. A more restricted definition of epitaxial growth would include only those examples where the substrate imposes its own crystal structure, orientation, and lattice parameter on the adsorbed overlayer. (This restricted definition is also called pseudomorphic growth.)... 

The Eqs. (14.21) and (14.22) together with estimated by considered above method parameters A nd allow to calculate the dimensions and [55]. In Fig. 14.11 the dependences of Renyi characteristic dimensions and on extrusion draw ratio for componors UHMPE-Al and UHMPE-bauxite. As one can see, at the definite values X XJ the componors structure transition from multifiractal (canonical spectrum, grows at q increase [59]) to regular fractal D- = occurs and then at X>X - again to multifiractal (pseudospectrum, D decreases at q growth). 

It was proposed to use the thermodynamics of small systems and Avrami equations to describe the formation processes of carbon nanostructures during recrystallization (graphitization) [6,7]. These equations are successfully applied [8] to forecast permolecular structures and prognosticate the conditions on the level of parameters resulting in the obtaining of nanostructures of definite size and shape. The equation was also used to forecast the formation of fibers [9]. The application of Avrami equations in the processes of nanostructure formation (a) embryo formation and crystal growth in polymers [8]—... 

Because relatively few experimental SANS data are available for IPNs, presently it is difficult to draw any definite conclusions about the structure of IPNs. As is seen from the data considered, the mechanism of phase separation is not mentioned in any work cited above. Meanwhile, this mechanism should determine if the application of any theory is possible for a given system. One may suggest that the Porod and Hosemann models may be used only for the nucleation and growth mechanism of phase separation, most typical for sequential IPNs. For simultaneous IPNs, where spinodal decomposition, as a rule, is more probable, it seems to be more reliable to determine only the heterogeneity parameters, not the radii of particles, if any. It is also necessary to keep in mind the possible changes of the mechanism of phase separation in the course of reaction. 

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