Elastic properties of degenerate f.c.c. crystal of polydisperse soft dimers at zero temperature

Abstract Many scientific-technological advances depend critically on solid-state elastic properties, their magnitudes, and their responses to variables like stress and temperature. This chapter provides the definitions and descriptions of elastic constants and emphasizes five aspects of engineering-material solid-state elastic constants: general properties; interrelationships; relationships, especially thermodynamic to other physical properties; changes during cooling from ambient to near-zero temperature; and near-zero-temperature behavior.

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Elastic properties of the fcc crystals of soft spheres with size dispersion at zero temperature

physica status solidi (b) ◽

10.1002/pssb.200777711 ◽

2008 ◽

Vol 245 (3) ◽

pp. 606-613 ◽

Cited By ~ 12

Author(s):

J. W. Narojczyk ◽

K. W. Wojciechowski

Keyword(s):

Elastic Properties ◽

Zero Temperature ◽

Soft Spheres ◽

Size Dispersion

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Temperature Dependence of the Elastic Behavior of Structurally Disordered Metallic Superlattices

MRS Proceedings ◽

10.1557/proc-229-85 ◽

1991 ◽

Vol 229 ◽

Cited By ~ 1

Author(s):

J. A. Jaszczak ◽

D. Wolf

Keyword(s):

Molecular Dynamics ◽

Temperature Dependence ◽

Elastic Properties ◽

Structural Disorder ◽

Elastic Behavior ◽

Zero Temperature ◽

High Angle ◽

Dynamics Simulations ◽

Homogeneous Temperature ◽

Modulation Wavelength

AbstractThe structure and elastic properties of superlattices composed of high-angle twist grain boundaries on (100) planes of copper are investigated as a function of both the modulation wavelength and temperature via molecular dynamics simulations. Comparison is made with zero-temperature results, where a stiffening of the Young's modulus normal to the interfaces and a softening of the modulus for shear parallel to the interfaces has previously been observed. The differences between the effects of homogeneous (temperature-induced) and inhomogeneous (interface-induced) structural disorder on the elastic properties is explored.

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Electron Microscopy and image reconstruction reveal the structural basis for spectrin's elastic properties

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100122952 ◽

1992 ◽

Vol 50 (1) ◽

pp. 510-511

Author(s):

Amy M. McGough ◽

Robert Josephs

Keyword(s):

Electron Microscopy ◽

Elastic Properties ◽

Conformational Changes ◽

Quaternary Structure ◽

Three Dimensional ◽

Membrane Skeleton ◽

Projection Algorithm ◽

Structural Basis ◽

Iterative Approximation ◽

Membrane Skeletons

The remarkable deformability of the erythrocyte derives in large part from the elastic properties of spectrin, the major component of the membrane skeleton. It is generally accepted that spectrin's elasticity arises from marked conformational changes which include variations in its overall length (1). In this work the structure of spectrin in partially expanded membrane skeletons was studied by electron microscopy to determine the molecular basis for spectrin's elastic properties. Spectrin molecules were analysed with respect to three features: length, conformation, and quaternary structure. The results of these studies lead to a model of how spectrin mediates the elastic deformation of the erythrocyte.Membrane skeletons were isolated from erythrocyte membrane ghosts, negatively stained, and examined by transmission electron microscopy (2). Particle lengths and end-to-end distances were measured from enlarged prints using the computer program MACMEASURE. Spectrin conformation (straightness) was assessed by calculating the particles’ correlation length by iterative approximation (3). Digitised spectrin images were correlation averaged or Fourier filtered to improve their signal-to-noise ratios. Three-dimensional reconstructions were performed using a suite of programs which were based on the filtered back-projection algorithm and executed on a cluster of Microvax 3200 workstations (4).

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The buckling of thin EM specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177386 ◽

1990 ◽

Vol 48 (4) ◽

pp. 850-851

Author(s):

A.R. Thölén

Keyword(s):

Electron Microscope ◽

Elastic Properties ◽

Crystal Surface ◽

Specimen Surface ◽

Radius Of Curvature ◽

Thin Foils ◽

Thin Electron ◽

Regular Patterns

Thin electron microscope specimens often contain irregular bend contours (Figs. 1-3). Very regular bend patterns have, however, been observed around holes in some ion-milled specimens. The purpose of this investigation is twofold. Firstly, to find the geometry of bent specimens and the elastic properties of extremely thin foils and secondly, to obtain more information about the background to the observed regular patterns.The specimen surface is described by z = f(x,y,p), where p is a parameter, eg. the radius of curvature of a sphere. The beam is entering along the z—direction, which coincides with the foil normal, FN, of the undisturbed crystal surface (z = 0). We have here used FN = [001]. Furthermore some low indexed reflections are chosen around the pole FN and in our fcc crystal the following g-vectors are selected:

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