Structure formation fractal-like structures

In contrast, the three- or two-dimensional morphologies of colloidal aggregates via Brownian particle trajectories show a fractal-like structure. One of the most prominent features of the surface deposits formed by the diffusion-limited aggregation mechanism is the formation of isolated treelike clusters (9). In our experiments, the surface morphology of the silica-coated polyethylene composite prepared by... 

Formation of platinum fractal-like structures is possible by PA-CVD (19% Ar, 80% O2, 1% SnMe4) on tin oxide thin films using Pt(acac)2 as starting material . The platinum aggregates show a dendritic structure of fractional dimension D ca 1.1-1.6 (Figure 10). The occurrence of such aggregates has been correlated to the concentration of the platinum precursor and to the radio-frequency power applied to the substrate electrode. Fabrication of microsensors integrated on silicon wafers with the help of photoresistors is possible . 

The fate of nuclei is partiele eoagulation, a process in which small particles (assumed to be spherical) collide with each other and coalesce completely to form larger spherical particles. Small particles are indeed spheroidal and the assumption of spherical particles seems to be reasonable (Mitchell and Frenklach 2003, Balthasar et al. 2005). After a certain size, however, the partieles cannot coalesce completely and start to form long chains, which eventually grow into three-dimensional fractal-like structures. Fig. 4.15 shows the new partiele formation and growth pathways. A great role is played by the surface coating of primary hydrophilic soot... 

Thin film technology is becoming one of the important technologies today. While there are infinite varieties of thin film fabrication methods, most amorphous thin films seem to exhibit fractal-like atomic structures. Depending on the fabrication conditions, a thin film grows on the substrate into columnar structures with many voids interdispersed in the thin film.80 These structures can be seen in the field ion microscope, and compositional variation can be analyzed with the atom-probe. In addition, formation of atomic clusters inside the thin film can be substantiated with the observation of a large fraction of cluster ions in field evaporation by the atom-probe. 

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