Temperature and composition dependence of the tetragonal-orthorhombic distortion inLa2−xSrxCuO4−δ

1987 ◽  
Vol 35 (13) ◽  
pp. 7191-7194 ◽  
Author(s):  
R. M. Fleming ◽  
B. Batlogg ◽  
R. J. Cava ◽  
E. A. Rietman
Keyword(s):  
Composition Dependence ◽  
Orthorhombic Distortion

A study of twinning in YBa2Cu3O7−x by large-angle convergent-beam electron diffraction

1990 ◽  
Vol 48 (4) ◽  
pp. 20-21
Author(s):  
P.A. Midgley ◽  
R. Vincent ◽  
D. Cherns
Keyword(s):  
Electron Diffraction ◽  
Oxygen Atom ◽  
Strain Field ◽  
Large Angle ◽  
Convergent Beam Electron Diffraction ◽  
Orthorhombic Distortion ◽  
Beam Electron ◽  
Resultant Powder ◽  
Convergent Beam ◽  
Mesh Grid

The oxygenation of YBa2Cu3O7−x (YBCO) leads to an orthorhombic distortion of the unit cell to accommodate the extra oxygen atom. This makes the formation of twins energetically favourable with CuO4 planar unit chains running alternately along the a and b axes of the parent tetragonal structure. The geometry of this twinning is such that four possible twin variants may co-exist with the twin boundaries lying in the (110) or (110) planes of the deformed structure. The traces of these planes are not mutually perpendicular and thus the crystal is strained to allow for the mismatch. It is to the nature of this strain field that this work has been addressed.Sintered samples were prepared by crushing and dispersing the resultant powder onto a very fine Cu mesh grid. Single crystals were chemically thinned to perforation. No discernible artefacts were seen and similar results were obtained with either method.

Epitaxial Growth in Dislocation-Free Strained Alloy Films

2002 ◽  
Vol 715 ◽  
Author(s):  
Zhi-Feng Huang ◽  
Rashmi C. Desai
Keyword(s):  
Deposition Rate ◽  
Elastic Moduli ◽  
Composition Dependence ◽  
Critical Thickness ◽  
Lattice Misfit ◽  
Misfit Strain ◽  
Joint Stability ◽  
Alloy Films ◽  
The Stability ◽  
Stability Results

AbstractThe morphological and compositional instabilities in the heteroepitaxial strained alloy films have attracted intense interest from both experimentalists and theorists. To understand the mechanisms and properties for the generation of instabilities, we have developed a nonequilibrium, continuum model for the dislocation-free and coherent film systems. The early evolution processes of surface pro.les for both growing and postdeposition (non-growing) thin alloy films are studied through a linear stability analysis. We consider the coupling between top surface of the film and the underlying bulk, as well as the combination and interplay of different elastic effects. These e.ects are caused by filmsubstrate lattice misfit, composition dependence of film lattice constant (compositional stress), and composition dependence of both Young's and shear elastic moduli. The interplay of these factors as well as the growth temperature and deposition rate leads to rich and complicated stability results. For both the growing.lm and non-growing alloy free surface, we determine the stability conditions and diagrams for the system. These show the joint stability or instability for film morphology and compositional pro.les, as well as the asymmetry between tensile and compressive layers. The kinetic critical thickness for the onset of instability during.lm growth is also calculated, and its scaling behavior with respect to misfit strain and deposition rate determined. Our results have implications for real alloy growth systems such as SiGe and InGaAs, which agree with qualitative trends seen in recent experimental observations.

Melting and Crystallization of Poly(oxyethylene) Mixtures

1995 ◽  
Vol 60 (11) ◽  
pp. 1855-1868 ◽  
Author(s):  
Ivo Lapeš ◽  
Josef Baldrian ◽  
Ján Biroš ◽  
Julius Pouchlý ◽  
Hanes Mio
Keyword(s):  
Melting Point ◽  
Lamellar Structure ◽  
Composition Dependence ◽  
Eutectic Phase ◽  
Eutectic Melting ◽  
Pure Polymer ◽  
X Ray ◽  
Long Period ◽  
Solid Liquid ◽  
Melting And Crystallization

Solid-liquid eutectic phase diagrams of mixtures of poly(oxyethylene) (M.w. 2 000) with hydroxy and methoxy endgroups, crystallizing in extended-chain macroconformation only, with glutaric acid, benzoic acid or 1,2-diphenylethane are given. The composition dependence of the melting temperature can be fitted by the Flory-Huggins equation. Interaction parameters X and interaction energy densities B evaluated from the diluent branch of the phase diagram are consistent with those obtained from the polymer branch provided the calorimetric value of enthalpy of polymer fusion is used in the latter computation. Measurements of small- and wide-angle X-ray scatterings showed a stacked lamellar structure of POE. Below the eutectic melting point, the long period of the polymer is almost independent of the diluent concentration. On raising temperature gradually from this melting point to the melting point of pure polymer, the increasing long period indicates the penetration of the diluent between the lamellae. As follows from SAXS measurements, the crystallinity of poly(oxyethylene) in the mixtures remains unchanged compared to that of the pure polymer.

Composition dependence of the DC conductivity in (CuPc) sakap 6 mixtures: Yoshida model application

1991 ◽  
Vol 123 (2) ◽  
pp. K145-K148 ◽  
Author(s):  
R. Piasecki ◽  
Z. Ziembik ◽  
W. Wacławek ◽  
M. Zabkowska-Wacławek
Keyword(s):  
Composition Dependence ◽  
Dc Conductivity ◽  
Model Application

Corrigendum to “Composition dependence of indentation deformation and indentation cracking in glass” [Acta Mater. 61 (2013) 5949-5965]

2021 ◽  
Vol 208 ◽  
pp. 116738
Author(s):  
P. Sellappan ◽  
T. Rouxel ◽  
F. Celarie ◽  
E. Becker ◽  
P. Houizot ◽  
...  
Keyword(s):  
Composition Dependence ◽  
Acta Mater

scholarly journals Predicting the photocurrent-composition dependence in organic solar cells

2021 ◽  
Author(s):  
Xabier Rodríguez-Martínez ◽  
Enrique Pascual San José ◽  
Zhuping Fei ◽  
Martin Heeney ◽  
Roger Guimera ◽  
...  
Keyword(s):  
Solar Cells ◽  
Organic Photovoltaics ◽  
Organic Solar Cells ◽  
Composition Dependence ◽  
Continuous Development

The continuous development of improved non-fullerene acceptors and deeper knowledge of the fundamental mechanisms governing performance underpin the vertiginous increase in efficiency witnessed by organic photovoltaics. While the influence of...

Composition dependence of physical properties in Pr0.7Ca0.3Mn1−xNixO3

2017 ◽  
Vol 693 ◽  
pp. 631-641 ◽  
Author(s):  
R. Jemai ◽  
R. M'nassri ◽  
A. Selmi ◽  
H. Rahmouni ◽  
K. Khirouni ◽  
...  
Keyword(s):  
Physical Properties ◽  
Composition Dependence

Anomalous composition dependence of anisotropy in amorphous Tb‐Fe and Ho‐Fe (abstract)

1991 ◽  
Vol 69 (8) ◽  
pp. 5466-5466
Author(s):  
F. Hellman ◽  
E. M. Gyorgy ◽  
R. B. van Dover ◽  
R. J. Felder
Keyword(s):  
Composition Dependence

Composition dependence of indentation deformation and indentation cracking in glass

2013 ◽  
Vol 61 (16) ◽  
pp. 5949-5965 ◽  
Author(s):  
P. Sellappan ◽  
T. Rouxel ◽  
F. Celarie ◽  
E. Becker ◽  
P. Houizot ◽  
...  
Keyword(s):  
Composition Dependence
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