Irregular grains

The same mechanism of zinc electrodeposition on the GC electrode was observed in sulfate, chloride, and acetate ion solutions [227]. The anions mainly affected the nucleation densities during zinc deposition, which resulted in a different surface morphology. The nucleation rate constant was the same in the chloride and sulfate solutions and was equal to 1.22 x 10 s h In the presence of acetate and chloride ions, the deposited zinc film tends to grow in a multilayered pattern, while in sulfate solution, the zinc deposition forms irregular grains. A new approach to the estimation of zinc electrocrystallization parameters on the GC electrode from acetate solutions was described by Yu et al. [228]. 

Granulite. A British, large, irregular grain, smokeless proplnt consisting of NC 46.3,... 

Hailstone bort IX bort, aggregate of irregular grains... 

Models for following the hydrogen diffusion process may be based on Monte Carlo simulation or network simulation incorporating both a regular lattice structure and irregular grain regions (Herrmann et ah, 2001). 

Fig. 5 Cascading flow occurs in large tumblers or during tumbling of fine, but freely flowing, grains. This snapshot shows a 1 m diameter transparent disk tumbler partially filled with colored 500 im irregular grains. The free surface is manifestly not flat, and the cascading layer is thin and nearly uniform with distance along the flowing surface.

The preparation of silica gel in the form of irregular grains, used in preparative chromatography, proceeds in a different fashion. First, orthosilicic acid is formed which... 

Material(s). The sternpost is a quarter section of top-growth white oak with knots and irregular grain orientation at one end. 

Fig. 48. (a) Junction of three different crystals of B in epitaxial growth on A, related to each other by a rotation of 2ir/3 about the [001] axis of A T and III, IIP and V, V and I are in quite perfect twin position, but not I and III, I and V or III and V. In the region where these three domains meet, new domains I, IH", V" can occur. They are in twin position with their neighbouring crystals with III and V for I", V and I for III", I and III for V". When they meet, since they are not related by twin position, new domains occur, and so on. This situation gives rise to a star feature which is characteristic of this kind of phase transformations, (b) When I", III", V" meet, three new domains I", III", V" occur, and so on. Finally, domains are separated by irregular grain boundaries. 

In general, the suspension polymerization can be distinguished into two types, namely, the bead and powder suspension polymerization [4]. In the former process, the polymer is soluble in its monomer and smooth spherical particles are produced. In the later process, the polymer is insoluble in its monomer and, thus, precipitates out leading to the formation of irregular grains or particles. The most important thermoplastic produced by the bead suspension polymerization process is PS. In the presence ofvolatile hydrocarbons (C4—C6), foamable beads, the so-called EPS, are produced. On the other hand, PVC, which is the second largest thermoplastic manufactured in the world, is an example of the powder type suspension polymerization. 

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