In-plane elasticity of a multi re-entrant auxetic honeycomb

Hierarchical honeycomb auxetic metamaterials

Most conventional materials expand in transverse directions when they are compressed uniaxially resulting in the familiar positive Poisson's ratio. Here we develop a new class of two dimensional (2D) metamaterials with negative Poisson's ratio that contract in transverse directions under uniaxial compressive loads leading to auxeticity. This is achieved through mechanical instabilities (i.e., b...

Phonons in conventional and auxetic honeycomb lattices

Mechanical Properties of Auxetic Cellular Material Consisting of Re-Entrant Hexagonal Honeycombs

A preliminary study of the mechanical properties of auxetic cellular material consisting of re-entrant hexagonal honeycombs is presented. For different scales of the honeycombs, the finite element method (FEM) and experimental models are used to perform a parametric analysis on the effects of the Poisson's ratio (cell angle) and the relative density (cell thickness) of honeycombs on bearing cap...

Twin plane re-entrant mechanism for catalytic nanowire growth.

A twin-plane based nanowire growth mechanism is established using Au catalyzed Ge nanowire growth as a model system. Video-rate lattice-resolved environmental transmission electron microscopy shows a convex, V-shaped liquid catalyst-nanowire growth interface for a ⟨112⟩ growth direction that is composed of two Ge {111} planes that meet at a twin boundary. Unlike bulk crystals, the nanowire geom...

Re-entrant Ventricular Arrhythmias

Retrograde atrial preexcitation following premature ventricular beats during reciprocating tachycardia in the Wolff-Parkinson-White syndrome. Eur J Cardiol 3: 283, 1975 28. Rosen KM, Denes P, Wu D, Dhingra RC: Electrophysiological diagnosis and manifestation of dual A-V nodal pathways. In Conduction System of the Heart, edited by Wellens HJJ, Lie H, Janse MJ. The Netherlands, H.E. Stenfert Kroe...