Glass-ceramics containing pyroelectric Sr2TiSi2O8 (STS) crystals are produced from parent glasses of compositions STS + 0.8 SiO2 (0.2 − x) Na2O x CaO, with = 0; 0.05; 0.10; and 0.15. The aim this work is to investigate the effect additions stoichiometric composition on crystallization mechanisms piezoelectric properties glass-ceramic. DSC analyses evidence that glass transition temperatures Tg,...

background : in anterior endodontically treated teeth a better esthetic can be achieved by using all-ceramic post -core restorations instead of metal post systems. maximum retention and fracture resistance of the post are the criteria upon which selection of a post system is based. the aim of this study was to evaluate the fracture resistance and retention of two all-ceramic post and core syste...

New types of ceramic coatings based on SiO2-Na2O-B2O3-TiO2 oxide phases were investigated as protection for boiler steel in power generation systems. Low-alloyed Cr-Mo 16Mo3 was coated with different compositions enamel to assess the protective potential these under water vapor at high temperatures. Oxidation 650 °C 50 h Ar + performed a TGA apparatus investigate oxidation kinetics. The results...

A new technique using impedance spectroscopy was developed to estimate the oxidation kinetics of pyrolytic carbon interphase layer in SiCf/SiC ceramic matrix composites. The AC Nyquist plot showed two semicircles that were curve-fitted an equivalent circuit with constant-phase element components. analysis results revealed capacitance low-frequency region decreased increasing time, whereas high-...

We present here comparative assessments of murine lung toxicity (biocompatibility) after in vitro and in vivo exposures to carbon (C-SiO2-etched), carbon-silica (C-SiO2), carbon-cobalt-silica (C-Co-SiO2), and carbon-cobalt oxide-silica (C-Co3O4-SiO2) nanoparticles. These nanoparticles have potential applications in clinical medicine and bioimaging, and thus their possible adverse events require...

Fracture behavior via a flexural test for newly found CaO–Al2O3–SiO2 (CAS) glass-ceramic (GC) was compared with that of enstatite GC and mica GC, which are well-known GCs high-fracture toughness machinability, respectively. By focusing on the nonelastic load–displacement curves, CAS characterized as less brittle material similar to machinable showed higher fracture toughness, KIC. The microcrac...

Engineered amorphous silica nanoparticles (SiO2 NPs), due to simple and low cost production, are increasingly used in commercial products and produced on an industrial scale. Despite the potential benefits, there is a concern that exposure to certain types of SiO2 NPs may lead to adverse health effects. As some NPs can cross the blood--brain barrier and may, in addition, reach the central nervo...

Nanofluids have gained attention for their potential to solve overheating problems in various industries. They are a mixture of base fluid and nanoparticles dispersed on the nanoscale. The can be metallic, ceramic, or carbon based, depending desired properties. While nanofluids offer advantages, challenges such as nanoparticle agglomeration, stability, cost effectiveness remain. Nonetheless, on...

Spent Foundry Sand is one of the largest industrial solid wastes generated by foundries in production iron and steel components. Currently, millions tons molten sands are discarded worldwide. Therefore, this work aims to reuse for glass-ceramic materials, since minimizes environmental impacts related its discarding. The Sand, composed >60% SiO2, was mixed with limestone melted at 1500 °C produc...