Many diverse applications utilize hydrogels as carriers, sensors, and actuators, and these applications rely on the refined control of physical properties of the hydrogel, such as elastic modulus and degree of swelling. Often, hydrogel properties are interdependent; for example, when elastic modulus is increased, degree of swelling is decreased. Controlling these inverse dependencies remains a ...

We report here the first experimental measurements of nonlinear rheological material properties of hagfish slime, a hydrated biopolymer/biofiber network, and develop a microstructural constitutive model to explain the observed nonlinear viscoelastic behavior. The linear elastic modulus of the network is observed to be G′ ≈ 0.02 Pa for timescales 0.1 s ≤ t ≤ 10 s, making it one of the softest el...

The goal of this study was to obtain a complete description of the elastic modulus and hysteresis of the mantle tissue of the squid Loligo pealei over the entire functional region of the mantle. In addition, in vivo strains were measured to allow calculations of the amount of energy stored and returned in each region of the mantle studied, and microscopic analysis of the tissue was carried out ...

Several models have been developed to extract the intrinsic elastic modulus of thin films from the composite film/substrate modulus value obtained from indentation tests on coated systems. Either analytical, semi-analytical or empirical, they generally propose an expression of the composite modulus as a function of the film and substrate elastic moduli and of the film thickness. When the substr...

I 4 ¯ -carbon was first proposed by Zhang et al., this paper will report regarding this phase of carbon. The present paper reports the structural and elastic properties of the three-dimensional carbon allotrope I 4 ¯ -carbon using first-principles density functional theory. The related enthalpy, elastic constants, and phonon spectra confirm that the newly-predicted I 4 ¯ -carbon is thermodynami...

Mechanical properties of ZnS nanobelts were measured at room temperature by direct nanoindentation experiments. It was found that the ZnS nanobelts achieve 79% increase in hardness but 52% decrease in elastic modulus compared to bulk ZnS. The nanobelts were found to exhibit creep under indentation. Indentation cracking was preferred along the belt growth direction. Indentation deformation behav...

Recent progress on studies of the nanoscale mechanical responses in disordered systems has highlighted a strong degree of heterogeneity in the elastic moduli. In this contribution, using computer simulations, we study the elastic heterogeneities in athermal amorphous solids--composed of isotropic static sphere packings--near the jamming transition. We employ techniques based on linear response ...