Results 251 to 260 of about 518,016 (300)

Calcium oxalate crystal morphology

Trends in Plant Science, 2002
Plants invest considerable resources of carbon and calcium in crystal formation, indicating that it is an important basic process in growth and development. The diversity of crystal shapes, as well as their prevalence and spatial distribution, have led to several hypotheses regarding crystal function in plants.
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Morphology of Oligomer Crystals

Proceedings, annual meeting, Electron Microscopy Society of America, 1973
Poly(ethylene terephthalate) (PET), contains approximately 1.5% oligomer (cyclic trimer). When films are heated the oligomers tend to migrate out and crystallize on the surface. The isolation and identification of oligomer has been reported; the crystal structure has been studied by x-ray and electron diffraction. Except for some optical work, however,
Y. T. Chen, E. A. Bartkus
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Crystal Morphology and Crystal Symmetry

2003
Crystallography grew up empirically as a branch of mineralogy. It was supported by laws deduced from observations, such as the law of constancy of interfacial angles and the law of rational intercepts, and involved mainly the recognition, description, and classification of naturally occurring crystal species, that is, it was a study of the morphology ...
Mark Ladd, Rex Palmer
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Crystallization and Morphology

1989
The crystalline high polymers represent a class of materials which, in the solid state, exhibit a complex hierarchical morphology in which structural ordering occurs over a wide range of dimensional levels. These range from spacings of the order of angstroms between neighbouring chains within a crystal lattice through the tens of nanometres to microns ...
Alun S. Vaughan, David C. Bassett
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Morphology of melt-crystallized syndiotactic polypropylene

Journal of Electron Microscopy, 2002
A transmission electron microscopy (TEM) study was made to investigate the mechanism of isothermal crystallization from melt for syndiotactic polypropylene (sPP) with a syndiotactic pentad fraction of 0.92. The TEM morphologies of RuO4-stained and ultrathin-sectioned specimens revealed a clear assignment of lamellar crystals with different crystal ...
Jun-ichi, Harasawa, Hiroki, Uehara, Takeshi, Yamanobe, Tadashi, Komoto   +3 more
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Morphologies of CVD ZrC Crystals

Physica Status Solidi (a), 1981
Particulate ZrC crystals of well-defined morphologies are formed by chemical vapor deposition from the ZrBr4–CH4–H2–Ar system. The basic forms are considered to be the prisms of 〈110〉axis having rhombic, pseudo-rhombic, and trigonal cross sections, which are bounded with four {111}, two {111} and two {110}, and two {111} and one {100} side faces ...
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Nucleation and Morphology of Chymotrypsinogen Crystals

Nature, 1964
IT has been suggested recently1 that the morphology of enzyme crystals grown from solutions at various super-saturations2 may be interpreted in terms of the basic mechanisms of nucleation. Little is known of either the nucleation mechanism or the solid-state properties of enzymes, since most are notoriously unstable even under mild conditions. The work
J A, HAMILTON, J A, KOUTSKY, A G, WALTON
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Template‐Directed Control of Crystal Morphologies

Macromolecular Bioscience, 2007
AbstractBiominerals are characterised by unique morphologies, and it is a long‐term synthetic goal to reproduce these synthetically. We here apply a range of templating routes to investigate whether a fascinating category of biominerals, the single crystals with complex forms, can be produced using simple synthetic methods.
Meldrum, Fiona C., Ludwigs, Sabine
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Screening-controlled morphologies of Yukawa crystals

The Journal of Chemical Physics, 2010
Asymptotic expressions for the energies of Yukawa crystals, valid at the Coulomb and hard-sphere (i.e., the weak-screening and strong-screening) limits, are derived. Careful analysis of these limits elucidates the origin of the observed structural transitions that interconnect distinct particle configurations.
Jerzy, Cioslowski, Ewa, Grzebielucha
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Morphological equilibration of a facetted crystal

Physical Review B, 1992
We study the morphological equilibration of a finite, facetted crystal by use of phenomenological equations of motion. The relevant atomistic kinetic processes (edge transfer, kink attachment and/or detachment, terrace hopping, and surface diffusion) are introduced progressively with special attention given to a proper treatment of the latter.
, Ozdemir, , Zangwill
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