401 AFM observation of structural changes of polymer surface under simple shear deformation

2000 ◽  
Vol 2000.75 (0) ◽  
pp. _4-5_-_4-6_
Author(s):  
Isao TATSUNOKI ◽  
Yoshio KOUTA ◽  
Taiji ADACHI ◽  
Yoshihiro TOMITA
Keyword(s):  
Shear Deformation ◽  
Simple Shear ◽  
Structural Changes ◽  
Polymer Surface ◽  
Simple Shear Deformation ◽  
Afm Observation

Shear properties of passive ventricular myocardium

2002 ◽  
Vol 283 (6) ◽  
pp. H2650-H2659 ◽  
Author(s):  
Socrates Dokos ◽  
Bruce H. Smaill ◽  
Alistair A. Young ◽  
Ian J. LeGrice
Keyword(s):  
Shear Deformation ◽  
Simple Shear ◽  
Ventricular Myocardium ◽  
Left Ventricular ◽  
Shear Deformations ◽  
Shear Properties ◽  
Nonlinear Viscoelastic ◽  
Myocardial Layers ◽  
Shear Modes ◽  
Simple Shear Deformation

We examined the shear properties of passive ventricular myocardium in six pig hearts. Samples (3 × 3 × 3 mm) were cut from adjacent regions of the lateral left ventricular midwall, with sides aligned with the principal material axes. Four cycles of sinusoidal simple shear (maximum shear displacements of 0.1–0.5) were applied separately to each specimen in two orthogonal directions. Resulting forces along the three axes were measured. Three specimens from each heart were tested in different orientations to cover all six modes of simple shear deformation. Passive myocardium has nonlinear viscoelastic shear properties with reproducible, directionally dependent softening as strain is increased. Shear properties were clearly anisotropic with respect to the three principal material directions: passive ventricular myocardium is least resistant to simple shear displacements imposed in the plane of the myocardial layers and most resistant to shear deformations that produce extension of the myocyte axis. Comparison of results for the six different shear modes suggests that simple shear deformation is resisted by elastic elements aligned with the microstructural axes of the tissue.

Twinning in pure Ti subjected to monotonic simple shear deformation

2012 ◽  
Vol 72 ◽  
pp. 24-36 ◽  
Author(s):  
W. Tirry ◽  
S. Bouvier ◽  
N. Benmhenni ◽  
W. Hammami ◽  
A.M. Habraken ◽  
...  
Keyword(s):  
Shear Deformation ◽  
Simple Shear ◽  
Simple Shear Deformation

Technical development of simple shear deformation experiments using a deformation-DIA apparatus

2010 ◽  
Vol 21 (5) ◽  
pp. 523-531 ◽  
Author(s):  
Tomohiro Ohuchi ◽  
Takaaki Kawazoe ◽  
Norimasa Nishiyama ◽  
Nishihara Yu ◽  
Tetsuo Irifune
Keyword(s):  
Shear Deformation ◽  
Simple Shear ◽  
Technical Development ◽  
Simple Shear Deformation

scholarly journals Positive or negative Poynting effect? The role of adscititious inequalities in hyperelastic materials

2011 ◽  
Vol 467 (2136) ◽  
pp. 3633-3646 ◽  
Author(s):  
L. Angela Mihai ◽  
Alain Goriely
Keyword(s):  
Shear Deformation ◽  
Simple Shear ◽  
Shear Force ◽  
Pure Shear ◽  
Hyperelastic Materials ◽  
Isotropic Materials ◽  
Poynting Effect ◽  
Simple Shear Deformation ◽  
Biopolymer Gels

Motivated by recent experiments on biopolymer gels whereby the reverse of the usual (positive) Poynting effect was observed, we investigate the effect of the so-called ‘adscititious inequalities’ on the behaviour of hyperelastic materials subject to shear. We first demonstrate that for homogeneous isotropic materials subject to pure shear, the resulting deformation consists of a triaxial stretch combined with a simple shear in the direction of the shear force if and only if the Baker–Ericksen inequalities hold. Then for a cube deformed under pure shear, the positive Poynting effect occurs if the ‘sheared faces spread apart’, whereas the negative Poynting effect is obtained if the ‘sheared faces draw together’. Similarly, under simple shear deformation, the positive Poynting effect is obtained if the ‘sheared faces tend to spread apart’, whereas the negative Poynting effect occurs if the ‘sheared faces tend to draw together’. When the Poynting effect occurs under simple shear, it is reasonable to assume that the same sign Poynting effect is obtained also under pure shear. Since the observation of the negative Poynting effect in semiflexible biopolymers implies that the (stronger) empirical inequalities may not hold, we conclude that these inequalities must not be imposed when such materials are described.

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