Programming Shape Memory Hydrogel to a Pre?Encoded Static Deformation toward Hierarchical Morphological Information Encryption (Adv. Funct. Mater. 45/2022)

Materials and Wireless Microfluidic Systems for Electronics Capable of Chemical Dissolution on Demand (Adv. Funct. Mater. 92015)

Toward Hierarchical Identity-Based Encryption

We introduce the concept of hierarchical identity-based encryption (HIBE) schemes, give precise definitions of their security and mention some applications. A two-level HIBE (2-HIBE) scheme consists of a root private key generator (PKG), domain PKGs and users, all of which are associated with primitive IDs (PIDs) that are arbitrary strings. A user’s public key consists of their PID and their do...

Acoustic Switches: Harnessing Deformation to Switch On and Off the Propagation of Sound (Adv. Mater. 8/2016).

Isosurfaces of sound waves traveling through an architected material proposed by K. Bertoldi and co-workers on page 1631 are depicted. The material comprises a square array of elastomeric helices in background air and acts as an on/off acoustic switch. It is characterized by frequency ranges of strong wave attenuation (bandgaps) in the undeformed configuration. Upon deformation, the initial ban...

Metamaterials: Snapping Mechanical Metamaterials under Tension (Adv. Mater. 39/2015).

By exploiting snap-through instabilities, D. Pasini and co-workers design a damage-tolerant mechanical metamaterial that snaps sequentially under tension, thereby accommodating a very large deformation up to 150%. On page 5931, they describe how the nonlinear mechanical response of the metamaterial can be robustly programmed by tuning the architecture of its unit cell.

Deformation Properties of TiNi Shape Memory Alloy

In order to describe the deformation properties due to the martensitic transformation and the R-phase transformation of TiNi shape memory alloy, a thermomechanical constitutive equation considering the volume fractions of induced phases associated with both transformations is developed. The proposed constitutive equation expresses well the properties of the shape memory effect, pseudoelasticity...