Analyses of dynamic crack growth along interfaces are discussed. The material on each side of the bond line is characterized by an elastic constitutive relation. A cohesive surface constitutive relation that allows for the creation of new free surface is also specified across the bond line. The resistance to crack initiation and the crack speed history are then predicted without invoking any ad...

The study of brittle or fatigue fracture that involves contact along the crack faces is difficult for several reasons. On the one hand, material data pertaining to the growth of cracks in a compressive environment are scant, and, on the other, frictional stresses may be transmitted across the contacting crack faces. The analysis of cracks under these conditions is complicated. Nevertheless, sol...

Various concentrations of copper were embedded into silica matrix to xerogel forms using copper source Cu(NO3)2∙3H2O. The xerogel samples were prepared by hydrolysis and condensation of Tetraethyl Ortho-Silicate (TEOS) with determination of new molar ratio of the components by the sol-gel method. After ambient drying, the xerogel samples were heated from 60 to 1000˚C at a slow heating rate (50°...

A systematic study of the structure-function relationships critical to understanding the sensing mechanism of 1st generation amperometric glucose biosensors with an embedded nanoparticle (NP) network is presented. Xerogel-based films featuring embedded glucose oxidase enzyme and doped with alkanethiolate-protected gold NPs, known as monolayer protected clusters (MPCs), exhibit significantly enh...

Background: Polysaccharides are renewable biodegradable natural materials and are accounted for to control the formation of hybrid silica nanocomposites by sol gel process. Methods: The synthesis of templated silica xerogel essentially includes two critical steps of hydrolysis and polycondensation reaction that are started by catalyst and silica precursor solution. Aside from this Saponificatio...

This research studies the performance of a battery-free wireless antenna sensor for measuring crack propagation. In our previous work, a battery-free folded patch antenna was designed for wireless strain and crack sensing. When experiencing deformation, the antenna shape changes, causing shift in electromagnetic resonance frequency of the antenna. The wireless interrogation system utilizes the ...

In the current study, the effect of such parameters as the length, position and angle of crack on free vibrations of a cracked plate was examined by finite element method. The assumed crack was internal and through and its growth was ignored. In the proposed finite element model, crack was considered as a discontinuity on the plate surface and the results were compared with the results of other...

A final report submitted to the Infrastructure Technology Institute DISCLAIMER: The contents of this report reflect the views of the authors, who are responsible for the facts and accuracy of the information presented herein. This Document is disseminated under the sponsorship of the Synopsis: There have been numerous studies that have aimed at improving the low tensile strength, stiffness, and...

V2O5 xerogel films were fabricated by casting V2O5 sols onto fluorine-doped tin oxide glass substrates at room temperature. Five, ten and twenty atomic layers of Al2O3 were grown onto as-fabricated films respectively. The bare film and Al2O3-deposited films all exhibited hydrous V2O5 phase only. Electrochemical impedance spectroscopy study revealed increased surface charge-transfer resistance o...

Joint replacement is being actively developed within modern orthopedics. One novel material providing fast implantation is bioactive coatings. The synthesis of targeted nanocoatings on metallic nanotitanium surface is reported in this paper. TiO₂-based micro- and nanocoatings were produced by sol-gel synthesis using dip-coating technology with subsequent fast (shock) drying in hot plate mode at...