FRACTURAS “FÓSILES” EN ESQUELETOS DE EQUINOIDEOS DEL CRETÁCICO SUPERIOR - “FOSSIL” FRACTURES IN UPPER-CRETACEOUS EQUINOIDS TESTS

Mapping Intimacies ◽

10.31233/osf.io/trujp ◽

2021 ◽

Author(s):

Javier Gil Sevillano

Keyword(s):

Equilateral Triangle ◽

Fracture Process ◽

Upper Cretaceous ◽

Preferred Orientation ◽

Single Crystalline

Many calcitic skeletons of the fossil echinoid Micraster coranguinum show small triangular holes on their surface originated by the loss of a pyramidal fragment. The geometry of the holes, at first sight surprising, is simply explained by the intersection of fractures of the single crystalline skeleton plates along the three easy cleavage planes of calcite. The base of the pyramidal fragments is often close to an equilateral triangle; the morphology of such fractures is explained by the preferred orientation of the Micraster plates, whose surface is parallel to the basal calcite plane (0001). The fracture process leading to such fractures is most probably of thermo-elastic origin.

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Evolutionary growth of microscale single crystalline GaN on an amorphous layer by the combination of MBE and MOCVD

CrystEngComm ◽

10.1039/c5ce00543d ◽

2015 ◽

Vol 17 (30) ◽

pp. 5849-5859 ◽

Cited By ~ 6

Author(s):

Jung-Wook Min ◽

Si-Young Bae ◽

Won-Mo Kang ◽

Kwang Wook Park ◽

Eun-Kyu Kang ◽

...

Keyword(s):

Amorphous Layer ◽

Preferred Orientation ◽

Crystalline Quality ◽

Growth Step ◽

Mbe Growth ◽

Single Crystalline ◽

Amorphous Substrate ◽

Evolutionary Growth

Epitaxial GaN layers are grown on amorphous substrate by the combination of MBE and MOCVD. MBE growth step provided uniform, preferred orientation and MOCVD enabled improved crystalline quality.

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Tailoring of {116} faceted single crystalline anatase nanosheet arrays and their improved electrochemical performance

CrystEngComm ◽

10.1039/c5ce00408j ◽

2015 ◽

Vol 17 (23) ◽

pp. 4377-4382 ◽

Cited By ~ 2

Author(s):

Feng Li ◽

Xiaoning Li ◽

Shangfeng Yang ◽

Zhengping Fu ◽

Yalin Lu

Keyword(s):

Electrochemical Performance ◽

Preferred Orientation ◽

Single Crystalline ◽

Electrochemical Reversibility ◽

Nanosheet Arrays ◽

Reduction Capacity

Upright diamond structured anatase nanosheet arrays with a highly preferred orientation were obtained, which exhibited improved reduction capacity and electrochemical reversibility.

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Magnetic Properties of Highly-Ordered Ni, Co and Their Alloy Nanowires in AAO Templates

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.111.123 ◽

2006 ◽

Vol 111 ◽

pp. 123-126 ◽

Cited By ~ 4

Author(s):

H. Pan ◽

J.B. Yi ◽

B.H. Liu ◽

S. Thongmee ◽

J. Ding ◽

...

Keyword(s):

Magnetic Properties ◽

Surface Oxidation ◽

Preferred Orientation ◽

Metal Nanowires ◽

Bias Effect ◽

Large Shift ◽

Exchange Bias Effect ◽

Single Crystalline ◽

Alloy Nanowires ◽

Co Nanowires

We have fabricated metal/alumina hybrid materials by electrodepositon of metal nanowires into nanopores of anodic aluminum oxide templates. Single crystalline Ni and Co nanowires have been successfully fabricated. Structural characterization (XRD and HRTEM) shows that the single crystalline Ni nanowire has a preferred orientation along (220) direction. The preferred orientation of Co nanowire is along (100). These single crystalline Ni and Co nanowires have exhibited excellent magnetic properties. Their alloy nanowires have exhibited a large shift in hysteresis, probably due to the surface oxidation and exchange bias effect.

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Micrometre-length continuous single-crystalline nm-thin Fe3C-nanowires with unusual 010 preferred orientation inside radial few-wall carbon nanotube structures: the key role of sulfur in viscous boundary layer CVS of ferrocene

RSC Advances ◽

10.1039/c7ra00240h ◽

2017 ◽

Vol 7 (22) ◽

pp. 13272-13280 ◽

Cited By ~ 7

Author(s):

Filippo S. Boi ◽

Jiayu Wang ◽

Sameera Ivaturi ◽

Xi Zhang ◽

Shanling Wang ◽

...

Keyword(s):

Boundary Layer ◽

Carbon Nanotube ◽

Preferred Orientation ◽

Viscous Boundary Layer ◽

Single Crystalline ◽

Viscous Boundary

We report the observation of novel radial carbon nanotube structures with 2–5 walls filled with continuous single-crystalline Fe3C nanowires.

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The Microstructure of Shock-Synthesized Diamond

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010006163x ◽

1967 ◽

Vol 25 ◽

pp. 324-325

Author(s):

Lucien F. Trueb

Keyword(s):

Single Crystals ◽

Preferred Orientation ◽

High Magnification ◽

Texture Pattern ◽

Shock Process ◽

New Type ◽

Diffraction Diagram

A new type of synthetic industrial diamond formed by an explosive shock process has been recently developed by the Du Pont Company. This material consists of a mixture of two basically different forms, as shown in Figure 1: relatively flat and compact aggregates of acicular crystallites, and single crystals in the form of irregular polyhedra with straight edges.Figure 2 is a high magnification micrograph typical for the fibrous aggregates; it shows that they are composed of bundles of crystallites 0.05-0.3 μ long and 0.02 μ. wide. The selected area diffraction diagram (insert in Figure 2) consists of a weak polycrystalline ring pattern and a strong texture pattern with arc reflections. The latter results from crystals having preferred orientation, which shows that in a given particle most fibrils have a similar orientation.

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Existence of Cubic ZrO2 at 300°C on Bulk Zirconium

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100062749 ◽

1969 ◽

Vol 27 ◽

pp. 166-167

Author(s):

R.A. Ploc

Keyword(s):

Metal Oxide ◽

Metal Substrate ◽

Preferred Orientation ◽

Monoclinic Zirconia ◽

Epitaxial Relationship

The manner in which ZrO2 forms on zirconium at 300°C in air has been discussed in the first reference. In short, monoclinic zirconia nucleates and grows with a preferred orientation relative to the metal substrate. The mode of growth is not well understood since an epitaxial relationship which gives minimum misfit between the zirconium ions in the metal/oxide combination is not realized. The reason may be associated with a thin cubic or tetragonal layer of ZrO2 between the inner oxygen saturated metal and the outer monoclinic zirconia.

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“Preparation of Single Crystalline Gold Films for ED Studies”

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096424 ◽

1972 ◽

Vol 30 ◽

pp. 634-635

Author(s):

Joseph D. C. Peng

Keyword(s):

Crystal Morphology ◽

Diffraction Theory ◽

Scattering Matrix ◽

Vacuum Evaporation ◽

Gold Films ◽

Matrix Formulation ◽

Silver Films ◽

Single Crystalline ◽

Grating Pattern ◽

Stacking Disorder

The relative intensities of the ED spots in a cross-grating pattern can be calculated using N-beam electron diffraction theory. The scattering matrix formulation of N-beam ED theory has been previously applied to imperfect microcrystals of gold containing stacking disorder (coherent twinning) in the (111) crystal plane. In the present experiment an effort has been made to grow single-crystalline, defect-free (111) gold films of a uniform and accurately know thickness using vacuum evaporation techniques. These represent stringent conditions to be met experimentally; however, if a meaningful comparison is to be made between theory and experiment, these factors must be carefully controlled. It is well-known that crystal morphology, perfection, and orientation each have pronounced effects on relative intensities in single crystals.The double evaporation method first suggested by Pashley was employed with some modifications. Oriented silver films of a thickness of about 1500Å were first grown by vacuum evaporation on freshly cleaved mica, with the substrate temperature at 285° C during evaporation with the deposition rate at 500-800Å/sec.

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