Search results
Results from the WOW.Com Content Network
Quartz diorite is an igneous, plutonic (intrusive) rock, of felsic composition, with phaneritic texture. Feldspar is present as plagioclase (typically oligoclase or andesine) with 10% or less potassium feldspar. Quartz is present at between 5 and 20% of the rock. Biotite, amphiboles and pyroxenes are common dark accessory minerals.
Within surface science, a quartz crystal microbalance with dissipation monitoring (QCM-D) is a type of quartz crystal microbalance (QCM) based on the ring-down technique. It is used in interfacial acoustic sensing. Its most common application is the determination of a film thickness in a liquid environment (such as the thickness of an adsorbed ...
Quartz. Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO 4 silicon–oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO 2. Quartz is, therefore, classified structurally as a framework silicate mineral ...
Care and maintenance. Care and maintenance is a term used in the mining industry to describe processes and conditions on a closed mine site at which there is the potential to recommence operations at a later date. During the care and maintenance phase, production is stopped but the site is managed to ensure it remains in a safe and stable ...
Crystal filters are used in the intermediate frequency (IF) stages of high-quality radio receivers. They are preferred because they are very stable mechanically and thus have little change in resonant frequency with changes in operating temperature. For the highest available stability applications, crystals are placed in ovens with controlled ...
The room-temperature form of quartz, α-quartz, undergoes a reversible change in crystal structure at 573 °C to form β-quartz. This phenomenon is called an inversion, and for the α to β quartz inversion is accompanied by a linear expansion of 0.45%. This inversion can lead to cracking of ceramic ware if cooling occurs too quickly through ...
Benton said the man continued to follow them even when her family got on the plane during early boarding and sat down in their row. At that point, she knew she needed to say something as her kids ...
"the Dublin Archdiocese's pre-occupations in dealing with cases of child sexual abuse, at least until the mid 1990s, were the maintenance of secrecy, the avoidance of scandal, the protection of the reputation of the Church, and the preservation of its assets.