imperfect crystal

imperfect crystal

[im¦pər‚fekt ′krist·əl]
(crystallography)
A crystal in which the regular, periodic structure is interrupted by various defects.
References in periodicals archive ?
As the time frame for crystallization is small, an imperfect crystal structure and only a very small crystal superstructure are mainly found in this edge layer.
The sand and the other ingredients are put in a pot along with any imperfect crystal, where it bubbles away and melts.
On the basis of DSC and XRD analyses, we suggested that PTFE fibrils would be imperfect crystal.
It is generally recognized that a polymer of high molecular weight has better mechanical properties because of a high density of chain entanglement [28, 29] with relatively imperfect crystal structure.
X-ray diffraction on imperfect crystals, Willey, New York.
Imperfect crystals have a significantly lower area of melting peak than do primary crystals.
Compared with the neat sample, the spherulite size of nylon-6 was significantly increased and imperfect crystals formed after introducing PEO component.
The second recrystallization peak just before the melting point is quite interesting and may indicate the possibility of merging small imperfect crystals, which are formed by initial cold crystallization at [T.
For the PPOx samples that were exposed for 480 hr, differently from the PP samples that were exposed for 480 hr, the peak relative to imperfect crystals was deeper than the other one.
Bulk iPP and iPP nanofibers showed small exotherms ranging from 41 to 48[degrees]C, which can be attributed to the recrystallization of originally formed imperfect crystals during the heating process.
In fact, with increasing isothermal crystallization time, initially formed small and imperfect crystals are subjected to crystal perfection and lamellar thickening.
m] value might be associated with the abrupt increase of imperfect crystals of [beta] form [11, 12].