(n.) A mineral having a glassy fracture, occurring in translucent trapezohedral crystals. It is a silicate of alumina and potash. It is found in the volcanic rocks of Italy, especially at Vesuvius.
(n.) A leucoplast.
Example Sentences:
(1) Quantitative x-ray diffraction was performed on the fast- and slow-cooled porcelain specimens with standards containing leucite volume fractions of 0.111, 0.223, 0.334, and 0.445.
(2) Recently introduced with pleasing aesthetic qualities, IPS-Empress (Ivoclar, Schaan, Liechtenstein), a new European leucite-reinforced glass-ceramic, has finally drawn attention in some journals and has been reviewed with promising in vitro test results.
(3) Unpaired, one-tailed t tests were performed on the fast- and slow-cool data, and a significant increase (p less than 0.05) in the amount of leucite (as a function of the slow cooling) was found for each of the porcelains.
(4) A better understanding of compatibility of alloy and ceramic during refiring schedules based upon leucite phase transformations and the ramifications for porcelain failure is emerging.
(5) Besides low leucite and glass, we have found a second crystalline phase in the sintered and slow-cooled porcelains that we propose to be potash feldspar (K2O.Al2O3.6SiO2).
(6) The present study was undertaken to determine whether the increase in porcelain thermal expansion might be attributable to crystallization of additional leucite during slow cooling of the porcelain.
(7) Ceramography confirms the martensitic (displacive) nature of the transformation from high (cubic) to low (tetragonal) leucite upon cooling.
(8) X-ray diffraction analyses verified the leucite content in metal ceramic systems and ceramics of the nonbonded systems.
(9) The chief ingredient of each porcelain was leucite (K2O .
(10) Comparing the metal ceramic systems with the nonbonded systems, an increase in leucite content was observed in the nonbonded systems.
(11) Most commercial dental porcelains designed for ceramo-metallic restorations are partially crystallized feldspathic glasses (glass-ceramics) that consist of low (tetragonal) leucite (K2O.Al2O3.4SiO2) crystals embedded in a glassy matrix.
(12) The purpose of this study was to test the hypothesis that high-leucite content feldspathic porcelain can be strengthened best by thermal tempering followed by ion exchange, compared with either thermal tempering or ion exchange alone.
(13) The increases in the leucite volume fractions resulting from the slow cooling ranged from a low of 8.5% to a high of 55.8%, with an average increase of 26.9%.
(14) The structure analysed in the scanning electron microscope showed leucite in the dendritic and idiomorphic form.
(15) Some other components were metal oxides used as pigment and opaque, for regulating the recrystallization of leucite in the fused porcelain, for controlling the thermal expansion, and for diffusing in the both sides of alloy and porcelain.
(16) The dentine materials of the metal ceramic systems VMK 68 and Biodent as well as the ceramics of all ceramic systems Duceram, Cosmotech, Optec, IPS-Empress and Corum were tested for their leucite content.
Rock
Definition:
(n.) See Roc.
(n.) A distaff used in spinning; the staff or frame about which flax is arranged, and from which the thread is drawn in spinning.
(n.) A large concreted mass of stony material; a large fixed stone or crag. See Stone.
(n.) Any natural deposit forming a part of the earth's crust, whether consolidated or not, including sand, earth, clay, etc., when in natural beds.
(n.) That which resembles a rock in firmness; a defense; a support; a refuge.
(n.) Fig.: Anything which causes a disaster or wreck resembling the wreck of a vessel upon a rock.
(n.) The striped bass. See under Bass.
(v. t.) To cause to sway backward and forward, as a body resting on a support beneath; as, to rock a cradle or chair; to cause to vibrate; to cause to reel or totter.
(v. t.) To move as in a cradle; hence, to put to sleep by rocking; to still; to quiet.
(v. i.) To move or be moved backward and forward; to be violently agitated; to reel; to totter.
(v. i.) To roll or saway backward and forward upon a support; as, to rock in a rocking-chair.
Example Sentences:
(1) I approached the public inquiry after much soul-searching, weighing up the ramifications of "rocking the boat" with the potential longer-term gains of a more robust and sustainable regulator.
(2) He had links to networks including the Hammerskin Nation and was involved in an underground music scene often referred to as "white power music" or "hate rock".
(3) The Ibiza Rocks hotel is aimed at a young clientele who'd never make it into the VIP section of Pacha.
(4) Meanwhile, Brighton rock duo Royal Blood top this week's album chart with their self-titled album, scoring the UK's fastest selling British rock debut in three years.
(5) Facebook Twitter Pinterest Trump signs order reviving controversial pipeline projects “The Obama administration correctly found that the Tribe’s treaty rights needed to be respected, and that the easement should not be granted without further review and consideration of alternative crossing locations,” said Jan Hasselman, an attorney for the Standing Rock Sioux tribe.
(6) One species (the goldfish) has an extensive fundus circulation while the other (the rock bass) has a minimal one.
(7) You can tell them that Deutsche Bank remains absolutely rock solid, given our strong capital and risk position.
(8) Rocking the hepatocyte-splenocyte cultures changed the elution profile from linear to convex.
(9) The 180-acre imperial palace appears to send ripples through the surrounding urban grain like a rock thrown into a pond, forming the successive layers of ring-roads.
(10) Russell is a former director of Northern Rock while Crosby is the former chief executive of HBOS.
(11) Gunfire and explosions rocked Bangkok following clashes between pro-government "red shirts" and protesters, leading to fears of further violence as Thais head to the polls.
(12) "And if you're pursuing music as the equivalent of your nine-to-five, and you'd quite like to be doing that for years to come, it's in your interest not to rock the boat."
(13) It was sparked by Ferguson's decision to sue Magnier over the lucrative stud fees now being earned by retired racehorse Rock of Gibraltar, which the Scot used to co-own.
(14) The involvement of one of South Korea’s most powerful men has rocked the country’s business world, as it signalled that prosecutors were prepared to use the full force of the law against the head of a company whose revenues are equivalent to a fifth of the country’s GDP.
(15) Emotional reactivity of patients with endogenous depression and healthy test subjects towards classic and rock music was compared.
(16) The Volkswagen Group has announced €1bn (£750m) of spending cuts at its core VW division to help pay for a product overhaul following the emissions testing scandal that has rocked Europe’s biggest carmaker.
(17) Loss-making Northern Rock is axing another 680 jobs as it cuts costs in preparation for a return to the private sector after being nationalised in February 2008 .
(18) Big musical acts (such as BB King, Keith Urban and Queens of the Stone Age) appear during the summer concert lineup but there are also drop-in yoga sessions, and hiking and biking trails wind through sculpted rocks and wildflowers.
(19) Just about.” That one went over like a sublime Chris Rock riff.
(20) For a while yesterday, Hazel Blears's selfishly-timed resignation with her rude "rock the boat" brooch send shudders of revulsion through some in the party.