Triple-layer omnidirectional reflectors (ODRs) consisting of a semiconductor, a quarter-wavelength transparent dielectric layer, and a metal have high reflectivities for all angles of incidence. Internal ODRs (ambient material's refractive index n >> 1.0) are demonstrated that incorporate nanoporous SiO2, a low-refractive-index material (n = 1.23), as well as dense SiO2 (n = 1.46). GaP and Ag s...

Graphene is a novel material and currently popular as an enabler for the next-generation nanocomposites. Here, we report the use of graphene to improve the mechanical properties of nano-58S bioactive glass for bone repair and regeneration. And the composite scaffolds were fabricated by a homemade selective laser sintering system. Qualitative and quantitative analysis demonstrated the successful...

Biocompatibility of a new bioactive glass composition for medical applications was evaluated with the addition of fluorides, such as CaF2 and MgF2, for the substitution of Na2O in the conventional bioactive glass composition (SiO2-CaO-Na2O-P2O5). Also, the physical properties of these glass ceramics were investigated. When B2O3 was added as a Na2O substitution, the thermal expansion coefficient...

Apart from a good bioactive behavior, composite materials for dental applications should attain high mechanical properties. Thus, the aim of this work was the fabrication and characterization of novel sol-gel derived dental ceramics/bioactive glass composites and the investigation of their mechanical properties such as flexural strength and Weibull modulus. Fourier Transform Infrared Spectrosco...

to investigate and compare the amount of fluoride release of conventional, resin modified and nanofilled resin modified glass ionomer cements.tablets of glass-ionomer cements were immersed in deionized water and incubated at 37°c. after 1, 2, 7, 15 and 30 days, fluoride ion was measured under normal atmospheric conditions by fluoride ion selective electrode. buffer (tisab ii) was used to decomp...

SiO2 /Ge:SiO2 /SiO2 sandwiched structure was fabricated for exploring efficient light emission. After annealed in N2 (O2,1%), this structure shows three photoluminescence ~PL! bands at 293, 395, and 780 nm. The intensity of the 395 nm band is largely enhanced in comparison with that from the monolayered Ge:SiO2 film. Spectral analyses suggest that the three PL bands originate from S1→S0 , T((T)...

Hydrogen in the Earth's deep interior has been thought to exist as a hydroxyl group in high-pressure minerals. We present Muon Spin Rotation experiments on SiO2 stishovite, which is an archetypal high-pressure mineral. Positive muon (which can be considered as a light isotope of proton) implanted in stishovite was found to capture electron to form muonium (corresponding to neutral hydrogen). Th...

Bioactive glasses represent important biomaterials being investigated for the repair and reconstruction of diseased bone tissues, since they exhibit outstanding bonding properties to human bone. In the present study bioactive glass (type 45S5) nanoparticles (nBG) with a mean particle size in the range of 20-60 nm, synthesized by flame spray synthesis, are investigated in relation to in vitro bi...