An electrochemical etching technique has been developed that provides continuous control over the porosity of a porous silicon layer as a function of etching depth. Thin films with engineered porosity gradients, and thus a controllable gradient in the index of refraction, have been used to demonstrate broadband antireflection properties on silicon wafer and solar cell substrates. A simulation w...

BACKGROUND: The effective porosity is an important quantitative parameter for food products that has a significant effect on taste and quality. It is challenging to quantify the apparent porosity of fried potato crisps as they have a thin irregularly shaped cross section containing oil and water. This study uses a novel Micro-CT technique to determine the solid volume fraction and hence the eff...

We investigate the degree to which the nearly symmetric form of X-ray emission lines seen in Chandra spectra of early-type supergiant stars can be explained by the porous nature of their spatially structured stellar winds. Such porosity could effectively reduce the bound-free absorption of X-rays emitted by embedded wind shocks, and thus allow a more similar tranmission of redand blue-shifted w...

The Fracture Risk Assessment Tool (FRAX) and Garvan Calculator have improved the individual prediction of fracture risk. However, additional bone measurements that might enhance the predictive ability of these tools are the subject of research. There is increasing interest in cortical parameters, especially cortical porosity. Neither FRAX nor Garvan include measurements of cortical architecture...

OBJECTIVE Reduced bone mineral density (BMD), assessed by Dual Energy X-ray absorptiometry (DXA), is a well-known risk factor for fragility fracture. A large proportion of patients with fracture have only slightly reduced BMD. Assessment of other bone structure features than BMD may improve identification of individuals at increased fracture risk. Digital X-ray radiogrammetry (DXR), which is a ...

Small fractures in bone tissue can heal by themselves, but in case of larger defects current therapies are not completely successful due to several drawbacks. A possible strategy relies on the combination of additive manufactured polymeric scaffolds and human mesenchymal stromal cells (hMSCs). The architecture of bone tissue is characterized by a structural gradient. Long bones display a struct...

The injection of carbon dioxide (CO2) in deep, unmineable coalbeds is a very attractive option for geologic CO2 storage: the CO2 is stored and at the same time the recovery of coalbed methane (CBM) is enhanced. The revenue of methane (CH4) production can offset the expenditures of the storage operation. Coalbeds form complex gas reservoirs characterized by their dual porosity: they contain both...

Replamineform Inspired Bone Structures (RIBS) using multi-piece molds and advanced ceramic gelcasting technology.Abstract A new technology was developed for quickly, simply, and affordably creating Replamineform Inspired Bone Structures (RIBS) that combines multi-piece mold manufacturing for creating complex macroscale geometries with advanced ceramic gelcasting technology for controlling micro...

A program was designed to allow the study of the effects of several parameters on the injection of water into and production of fluid from a fractured low porosity geothermal reservoir with properties similar to those at The Geysers. Fractures were modeled explicitly with low porosity, high permeability blocks rather than with a dual-porosity formulation to gain insight into the effects of sing...