We report our results of continuous illumination of Ge46S54 chalcogenide glass films with bandgap light in air. The outcome of this process is the formation of Ge–S backbone depleted in germanium. We relate this to consumption of some of the germanium available in the initial material due to the occurrence of a photoinduced oxidation. This is proved using energy dispersion spectroscopy which sh...

Systematic experimentation on grain-boundary sliding of ceramics with a glassy film at grain boundaries has been carried out by low-frequency internal friction technique up to =2200K. A model silicon nitride polycrystal was selected for this basic investigation in which the grains were continuously encompassed by a nanometre-sized film of pure SiO, glass. The SiO, film was also doped with incre...

The compressive response of polymer matrix fiber reinforced unidirectional composites (PMC’s) is investigated via a combination of experiment and analysis. The study accounts for the nonlinear constitutive response of the polymer matrix material and examines the effect of fiber geometric imperfections, fiber mechanical properties and fiber volume fraction on the measured compressive strength an...

Electrode material for low-temperature co-fired diopside glass-ceramic used for microwave dielectrics was investigated in the present work. Diffusion of silver from the electrode to diopside glass-ceramics degrades the performance of the microwave dielectrics. Two approaches were adopted to resolve the problem of silver diffusion. Firstly, silicon-oxide (SiO₂) powder was employed and secondly c...

Glass ionomer cements (GICs) are clinically attractive dental materials that have certain unique properties that make them useful as restorative and luting materials. This includes adhesion to moist tooth structures and base metals, anticariogenic properties due to release of fluoride, thermal compatibility with tooth enamel, biocompatibility and low toxicity. The use of GICs in a mechanically ...

This study investigated the effect of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP)-modified glass ionomer cement (GIC) on shear bond strength (SBS) and remineralisation of artificial "caries-affected" dentine. Human dentine slices were demineralised and allocated to three groups: group 1, conventional GIC; group 2, CPP-ACP-modified GIC; and group 3, resin-modified GIC. The SBS wa...

Glass is a material which is used in the industry and household. The presence of defects or weaknesses in the glass has serious implications. In a glass substrate, the grey level of defects and background are hardly distinguishable and results in a low contrast image. The primary objective of this paper is to develop a method for detection of defects in a glass surface image such as subtle defe...

Pliny the Elder recorded that Phoenician sailors came ashore and, not finding any local materials suitable for supporting their cooking pots above the sandy shore, used lumps of trona (natural soda or sodium carbonate) that formed part of their ship’s cargo. As the trona was heated in the fire it combined with the sand to give a material that flowed. This story may not be entirely accurate but ...

It is extremely difficult to realize two conflicting properties-high hardness and toughness-in one material. Nano-polycrystalline stishovite, recently synthesized from Earth-abundant silica glass, proved to be a super-hard, ultra-tough material, which could provide sustainable supply of high-performance ceramics. Our quantum molecular dynamics simulations show that stishovite amorphizes rapidly...

OBJECTIVES The aim of this study was to investigate the effect of erosion on direct tooth-coloured restorations and adjacent enamel/dentine under low and normal simulated salivary flow rates. METHODS Bovine enamel and dentine specimens were prepared (n=16) and restored with the following materials: resin composite (FiltekZ250), resin-modified glass ionomer cement (Fuji II LC), high-viscosity ...