hexagonal platelet

hexagonal platelet

[hek′sag·ə·nəl ′plāt·lət]
(meteorology)
A small ice crystal of the hexagonal tabular form; the distance across the crystal from one side of the hexagon to the opposite side may be as large as about 1 millimeter, and the thickness perpendicular to this dimension is of the order of one-tenth as great; this crystal form is usually formed at temperatures of -10 to -20°C by sublimation; at higher temperatures the apices of the hexagon grow out and develop dendritic forms.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
The SEM image shows platelets with varying sizes in the range of 4 to 11 [micro]m, including a large hexagonal platelet with sharp edges.
Sharp edged hexagonal platelets with in-plane dimensions of several micrometers are observed in Figure 3(a), while much larger hexagonal platelets evolving through the DGG process are observed in Figure 3(b).
The SEM image for [Ba.sub.3][[Cu.sub.0.8-x][Zn.sub.x][[Mn.sub.0.2]].sub.2][Fe.sub.24][O.sub.41] (x = 0.4) sample in Figure 3(c) shows that a large fraction of the sample consists of sharp-edged hexagonal platelets with typical in-plane size of few micrometers, in addition to some larger particles and nonparticulate masses which may have evolved through DGG process.
Figure 3(d) shows a typical SEM image for the samples with x = 0.6, which also revealed the presence of a large fraction of sharp-edged hexagonal platelets with a typical in-plane size in the range of 1.5 to 4 [micro]m, in addition to large layered formations which may have evolved through the DGG process and topotactical reactions.
Zhong, "CTAB-assisted low-temperature synthesis of Sr[Fe.sub.12][O.sub.19] ultrathin hexagonal platelets and its formation mechanism," Materials Letters, vol.
Instead of having varying shapes, almost all the particles were hexagonal platelets 1 to 2 micrometers in diameter and 20 nanometers thick, Feldheim and Eaton report in an upcoming Science.