We report an aging effect on as-fabricated InGaAs/GaAs/Cr helical nanobelts. It has been observed that over time the nanobelt diameter first decreases and then increases until a constant value is reached. The gradual change of the diameter of the helical nanobelts from their original value is due to the competition of stress relaxation along the transverse and longitudinal axes of the nanobelts...

Stress is known to strongly alter the effective mass in semiconductors, changing the mobility of carriers. Transport measurements on AlGaN/GaN heterostructures indicated a large increase in mobility under tensile strain [M. Azize and T. Palacios, J. Appl. Phys. 108, 023707 (2010)]. Using first-principles methods, we calculate the variation of electron effective mass in GaN and AlN under hydrost...

Decellularized allografts offer potential as heart valve substitutes and scaffolds for cell seeding. The effects of decellularization on the quasi-static and time-dependent mechanical behavior of the pulmonary valve leaflet under biaxial loading conditions have not previously been reported in the literature. In the current study, the stress-strain, relaxation and creep behaviors of the ovine pu...

Glaucoma is a common ocular disease that causes irreversible loss of vision. Elevated intraocular pressure (IOP) is the primary risk factor for developing glaucoma. It is believed that increased IOP causes mechanical strain on the glial cells that support the retinal ganglion cell axons and thereby causes ganglion cell apoptosis [1,2]. This damage occurs in the optic nerve head (ONH) region of ...

174 LLE Review, Volume 79 Owing to its excellent homogeneity and low-intrinsic absorption properties, fused silica remains the preferred material for high-power laser applications over a wide wavelength range, but especially in the UV. In particular, large-aperture glass and excimer lasers, such as Nova, Beamlet, OMEGA, NIKE, and, in the foreseeable future, the National Ignition Facility (NIF),...

Mechanical instabilities that cause periodic wrinkling during compression of layered materials find applications in stretchable electronics and microfabrication, but can also limit an application's performance owing to delamination or cracking under loading and surface inhomogeneities during swelling. In particular, because of curvature localization, finite deformations can cause wrinkles to ev...

This paper summarizes the lessons learned from a full-scale test on two RC frame prototypes that have recently been tested on LNEC shaking-table using four pairs of biaxial synthetic ground motion records during 15WCEE Conference (2012). The reference structures are two single-story RC frames which are geometrically identical but with different reinforcement details. The simplified inelastic mo...

the present paper studies the possibility of propagation of torsional surface waves in an inhomogeneous anisotropic layer lying between two heterogeneous half-spaces (upper and lower half-space). both the half-spaces are assumed to be under compressive initial stress. the study reveals that under the assumed conditions, a torsional surface wave propagates in the medium. the dispersion relation ...

We calculate the quantum tunneling rate of a ferromagnetic particle of ∼ 100Å diameter in a magnetic field of arbitrary angle. We consider the magnetocrystalline anisotropy with the biaxial symmetry and that with the tetragonal symmetry. Using the spin-coherent-state path integral, we obtain approximate analytic formulas of the tunneling rates in the small ǫ(= 1−H/Hc)-limit for the magnetic fie...

Upon cooling, a thin metal film deposited on compliant elastomer substrate undergoes equi-biaxial compression and begins to buckle at a critical stress. As further cooling occurs, a highly ordered herringbone pattern self-assembles. The preference for the herringbone pattern over other potential modes is demonstrated based on minimum energy arguments. Control of the pre-buckling in-plane stress...