Grid maps for spaceflight, anyone? They are for free!

2013 ◽  
Vol 36 (5) ◽  
pp. 566-567 ◽  
Author(s):  
Federico Stella ◽  
Bailu Si ◽  
Emilio Kropff ◽  
Alessandro Treves
Keyword(s):  
Firing Rate ◽  
Single Unit ◽  
Three Dimensional ◽  
Rate Adaptation ◽  
Face Centered Cubic ◽  
Cubic Crystal ◽  
Unit Level ◽  
Face Centered ◽  
Approximate Periodicity ◽  
Firing Rate Adaptation

AbstractWe show that, given extensive exploration of a three-dimensional volume, grid units can form with the approximate periodicity of a face-centered cubic crystal, as the spontaneous product of a self-organizing process at the single unit level, driven solely by firing rate adaptation.

scholarly journals Synthesis and crystal structure of La21Cr8−2aAlbGe7−bC12[a= 0.22 (2) andb= 0.758 (19)]

2016 ◽  
Vol 72 (11) ◽  
pp. 1565-1568
Author(s):  
Jaskarun Pabla ◽  
Yuri Janssen ◽  
Jack W. Simonson
Keyword(s):  
Crystal Structure ◽  
Three Dimensional ◽  
Structure Type ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
Cubic Crystal ◽  
Synthesis And Crystal Structure ◽  
Geometrically Frustrated ◽  
The Face ◽  
Face Centered

Single crystals of a new multinary chromium carbide, La21Cr8−2aAlbGe7−bC12(henicosalanthanum octachromium aluminium hexagermanium dodecacarbide), were grown from an La-rich self flux and were characterized by single-crystal X-ray diffraction. The face-centered cubic crystal structure is composed of isolated and geometrically frustrated regular Cr tetrahedra that are co-centered within regular C octahedra. These mutually separated Cr4−aC6clusters are distributed throughout a three-dimensional framework of Al, Ge, and La. The title compound is isotypic with La21−δMn8X7C12andR21Fe8X7C12(R= La, Ce, Pr;X= Al, Bi, Ge, Sn, Sb, Te) and represents the first example of a Cr-based compound with this structure-type.

Epitaxial Ni nanoparticles on CaF2(001), (110) and (111) surfaces studied by three-dimensional RHEED, GIXD and GISAXS reciprocal-space mapping techniques

2017 ◽  
Vol 50 (3) ◽  
pp. 830-839 ◽  
Author(s):  
S. M. Suturin ◽  
V. V. Fedorov ◽  
A. M. Korovin ◽  
N. S. Sokolov ◽  
A. V. Nashchekin ◽  
...  
Keyword(s):  
Lattice Structure ◽  
Three Dimensional ◽  
Grazing Incidence ◽  
High Energy ◽  
Reciprocal Space ◽  
Mapping Technique ◽  
Face Centered Cubic ◽  
X Ray ◽  
Cubic Lattice ◽  
Face Centered

The development of growth techniques aimed at the fabrication of nanoscale heterostructures with layers of ferroic 3dmetals on semiconductor substrates is very important for their potential usage in magnetic media recording applications. A structural study is presented of single-crystal nickel island ensembles grown epitaxially on top of CaF2/Si insulator-on-semiconductor heteroepitaxial substrates with (111), (110) and (001) fluorite surface orientations. The CaF2buffer layer in the studied multilayer system prevents the formation of nickel silicide, guides the nucleation of nickel islands and serves as an insulating layer in a potential tunneling spin injection device. The present study, employing both direct-space and reciprocal-space techniques, is a continuation of earlier research on ferromagnetic 3dtransition metals grown epitaxially on non-magnetic and magnetically ordered fluorides. It is demonstrated that arrays of stand-alone faceted nickel islands with a face-centered cubic lattice can be grown controllably on CaF2surfaces of (111), (110) and (001) orientations. The proposed two-stage nickel growth technique employs deposition of a thin seeding layer at low temperature followed by formation of the islands at high temperature. The application of an advanced three-dimensional mapping technique exploiting reflection high-energy electron diffraction (RHEED) has proved that the nickel islands tend to inherit the lattice orientation of the underlying fluorite layer, though they exhibit a certain amount of {111} twinning. As shown by scanning electron microscopy, grazing-incidence X-ray diffraction (GIXD) and grazing-incidence small-angle X-ray scattering (GISAXS), the islands are of similar shape, being faceted with {111} and {100} planes. The results obtained are compared with those from earlier studies of Co/CaF2epitaxial nanoparticles, with special attention paid to the peculiarities related to the differences in lattice structure of the deposited metals: the dual-phase hexagonal close-packed/face-centered cubic lattice structure of cobalt as opposed to the single-phase face-centered cubic lattice structure of nickel.

scholarly journals Interactions between dislocations and three-dimensional annealing twins in face centered cubic metals

2019 ◽  
Vol 161 ◽  
pp. 371-378 ◽  
Author(s):  
Yanxiang Liang ◽  
Xiaofang Yang ◽  
Mingyu Gong ◽  
Guisen Liu ◽  
Qing Liu ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Face Centered Cubic ◽  
Cubic Metals ◽  
Annealing Twins ◽  
Face Centered

Electromagnetic Thermal Energy Transfer in Nanoparticle Assemblies Below Diffraction Limit

2020 ◽  
Vol 13 (2) ◽  
Author(s):  
Anil Yuksel ◽  
Edward T. Yu ◽  
Michael Cullinan ◽  
Jayathi Murthy
Keyword(s):  
Three Dimensional ◽  
Close Packing ◽  
Face Centered Cubic ◽  
Copper Nanoparticle ◽  
Colloidal Solutions ◽  
Plasmonic Coupling ◽  
Nanoparticle Assemblies ◽  
Enhanced Absorption ◽  
Face Centered ◽  
Insight Into

Abstract Fabrication of micro- and nanoscale electronic components has become increasingly demanding due to device and interconnect scaling combined with advanced packaging and assembly for electronic, aerospace, and medical applications. Recent advances in additive manufacturing have made it possible to fabricate microscale, 3D interconnect structures but heat transfer during the fabrication process is one of the most important phenomena influencing the reliable manufacturing of these interconnect structures. In this study, optical absorption and scattering by three-dimensional (3D) nanoparticle packings are investigated to gain insight into micro/nano heat transport within the nanoparticles. Because drying of colloidal solutions creates different configurations of nanoparticles, the plasmonic coupling in three different copper nanoparticle packing configurations was investigated: simple cubic (SC), face-centered cubic (FCC), and hexagonal close packing (HCP). Single-scatter albedo (ω) was analyzed as a function of nanoparticle size, packing density, and configuration to assess effect for thermo-optical properties and plasmonic coupling of the Cu nanoparticles within the nanoparticle packings. This analysis provides insight into plasmonically enhanced absorption in copper nanoparticle particles and its consequences for laser heating of nanoparticle assemblies.

The Influence of the Synthesis Method on the Formation of Phase Composition and Catalytic Centers Gd2Zr2O7

2020 ◽  
Vol 1009 ◽  
pp. 69-74
Author(s):  
Ekaterina Borisovna Markova ◽  
Alexander Genrihovich Cherednichenko ◽  
V.V. Kurilkin ◽  
J.M. Serov
Keyword(s):  
Crystal Structure ◽  
Synthesis Method ◽  
Nanocrystalline Powders ◽  
Face Centered Cubic ◽  
Cubic Crystal ◽  
Wide Range ◽  
Physicochemical Methods ◽  
Degradation Reaction ◽  
Cubic Structure ◽  
Face Centered

The influence of the type of crystal structure of complex gadolinium oxides on their catalytic activity was studied using a wide range of physicochemical methods. It was shown that the synthesized nanocrystalline powders Gd2Zr2O7 form highly symmetric face-centered cubic crystal structures. In the course of catalytic experiments, it was found that the formation of a cubic structure increases the degree of conversion of propane and the shift of cracking temperatures to a lower area. The formation of various defects contributes to the course of the dehydrogenation or degradation reaction due to the different number of catalytic centers.

On the Dynamical Propeties of a Strongly Anharmonic Face-Centered Cubic Crystal

1998 ◽  
Vol 12 (27n28) ◽  
pp. 2869-2879 ◽  
Author(s):  
V. I. Zubov ◽  
C. G. Rodrigues ◽  
M. F. Pascual
Keyword(s):  
Crystallographic Direction ◽  
Face Centered Cubic ◽  
Mean Square ◽  
Cubic Crystal ◽  
Cubic Lattice ◽  
Consistent Field ◽  
Self Consistent ◽  
Self Consistent Field ◽  
Face Centered ◽  
Anharmonic Crystals

We study the interatomic correlations and mean square relative displacements (MSRD) in anharmonic crystals on the basis of the correlative method of unsymmetrized self-consistent field (CUSF). Here we present general formulae for crystals with the anharmonicity, including the strong one, up to the fourth anharmonic terms and perform calculations of the quadratic correlation moments (QCM) in a crystal with face centered cubic lattice, namely in solid Ar. The second order of CUSF allows one to investigate correlations in this lattice between the nearest, second, third and fourth neighbors. The anharmonicity was demonstrated to have strong effect on the interatomic correlations at temperatures above 0.4 of the melting temperature causing a drastic rise near the spinodal point. The dependence of QCM on the distance between atoms and on the crystallographic direction is discussed.

Sign in / Sign up

Export Citation Format

Share Document