We show that gels formed by arrested spinodal decomposition of protein solutions exhibit elastic properties in two distinct frequency domains, both elastic moduli exhibiting a remarkably strong dependence on volume fraction. Considering the large difference between the protein size and the characteristic length of the network we model the gels as porous media and show that the high and low freq...

We report on quantifiable depth-dependent contact resonance AFM (CR-AFM) measurements over polystyrene-polypropylene (PS-PP) blends to detail surface and sub-surface features in terms of elastic modulus and mechanical dissipation. The depth-dependences of the measured parameters were analyzed to generate cross-sectional images of tomographic reconstructions. Through a suitable normalization of ...

In order to study the effects of structural variability, nanoindentation experiments were performed in Norway spruce cell walls with highly variable cellulose microfibril angle and lignin content. Contrary to hardness, which showed no statistically significant relationship with changing microfibril angle and lignin content, the elastic modulus of the secondary cell wall decreased significantly ...

A new imaging modality framework, called elasto-mammography, is proposed to generate the elastograms of breast tissues based on conventional X-ray mammography. The displacement information is extracted from mammography projections before and after breast compression. Incorporating the displacement measurement, an elastography reconstruction algorithm is specifically developed to estimate the el...

The elastic moduli of ultrathin poly(styrene) (PS) and poly(methylmethacrylate) (PMMA) films of thickness ranging from 200 nm to 5 nm were investigated using a buckling-based metrology. Below 40 nm, the apparent modulus of the PS and PMMA films decreases dramatically, with an order of magnitude decrease compared to bulk values for the thinnest films measured. We can account for the observed dec...

The ultimate properties of a fibrous composite system depend highly on the transverse mechanical properties of the fibers. Here, we report the size dependency of transverse elastic modulus in cellulose nanocrystals (CNCs). In addition, the mechanical properties of CNCs prepared from wood and cotton resources were investigated. Nanoindentation in an atomic force microscope (AFM) was used in comb...

The primary technical objective is to remotely generate and detect mid-frequency elastic waves within the body of a living cetacean and to use the measured propagation parameters of these waves to obtain the complex elastic moduli by inversion. A further technical objective is to extract moduli in this manner for intracranial tissues. This objective carries considerably more technical risk sinc...

The elastic properties of a zeolitic metal-azolate framework, Zn(mtz)2 (MAF-7, mtz− = 3methyl-1,2,4-triazolate), have been examined from the view point of the first principles calculations and experiments. Our results demonstrate that the three independent elastic constants of MAF-7 are about 5.0–73.3% higher than those of ZIF-8, though they are isomorphic. The electron-donating effect of the n...

We present a simple, implicit-solvent model for fluid bilayer membranes. The model was designed to reproduce the elastic properties of real bilayer membranes. For this model, we observed the solid-fluid transition and studied the in-plane diffusivity of the fluid phase. As a test, we compute the elastic-bending and area-compressing moduli of fluid bilayer membranes. We find that the computed el...

We have computed the elastic constants of nanostructured carbon films as obtained from classical molecular dynamics simulations of a cluster beam deposition process. The calculations show that the elastic constants of the deposited films are related to the average size of the clusters by a power law. This allows us to extrapolate the present theoretical data to the scale of the experimental res...