(n.) A mineral identical in composition with calcite or carbonate of lime, but differing from it in its crystalline form and some of its physical characters.
Example Sentences:
(1) The calcium carbonates-calcite, aragonite, and vaterite-constitute most of the remainder of the calculi.
(2) It is suggested that these substances may be vaterite and aragonite.
(3) Its absence in all analyzed invertebrate tissues (including calcitic, aragonitic, and apatitic mineral phases) indicates that matrix protein-bound gamma-carboxyglutamic acid is not obligatory for the calcification process in the invertebrates.
(4) Skeletal walls of more than one mineralogy have the magnesium-rich layer (calcite) surrounding the living chamber and the strontium-rich layer (aragonite) on the outside.
(5) The biocompatibility of mammal bone with aragonite and calcite skeletons of aquatic invertebrates (Corals, Molluscs) led us, after animal experimentation, to implant in humans artificial dental roots derived from such invertebrates.
(6) Toothpastes contain substances which promote dental health, such as abrasives (silicium dioxide, brushite, calcite, calcite and aragonite, gibbsite etc.
(7) But because cold water absorbs CO2 more quickly, the study predicts that levels of aragonite will fall by 60% to 80% by 2095 across the northern hemisphere.
(8) Aragonite seems to be formed slowly in undisturbed conditions.
(9) A gallstone of almost perfect octahedral symmetry was composed of a mixture of crystallites of the three polymorphous forms of calcium carbonate: calcite, aragonite, and vaterite.
(10) Peak milk yield paralleled dry matter intake and was higher when calcite flour and aragonite provided .9% calcium, intermediate when all sources provided .6% calcium, and lower when albacar provided .9% calcium.
(11) Dumbbell-like concretions of aragonite predominate during pregnancy and pseudopregnancy.
(12) The presence of calcite, aragonite and iron-containing pigment materials in the concretion is suggested.
(13) The variation in the amount of calcium carbonate formed with time was studied by weighing the precipitate, and the percentages of calcite, vaterite, and aragonite were determined by x-ray diffraction (XRD) analysis.
(14) But in our gallstone series in man, aragonite was most commonly found, with an occurrence rate of 90.6%, while that of calcite was 62.5%.
(15) In contrast, the distribution of gamma-carboxyglutamic acid in the vertebrates has been further extended by this study to include an apatitic shark tooth and an aragonitic fish otolith.
(16) Moreover three cases contained all three forms of calcium carbonate polymorphs; calcite, aragonite and vaterite.
(17) Such acidification spells problems for coral reefs, which rely on calcium minerals called aragonite to build and maintain their exoskeletons.
(18) The crystalline phases at the first few lamellae were mostly imperfect while the whole nacreous layer acquitted itself into a highly oriented biomineralized aragonite.
(19) The three cholesterols-cholesterol monohydrate, anhydrous cholesterol, and cholesterol II-account for 71% of the total crystalline material in the stones; the calcium carbonates-vaterite, aragonite, and calcite-contribute 15%, and calcium palmitate contributes 6%.
(20) It says that levels of aragonite, the type of calcium carbonate which is essential for marine organisms to make their skeletons and shells, will fall worldwide.
Calcite
Definition:
(n.) Calcium carbonate, or carbonate of lime. It is rhombohedral in its crystallization, and thus distinguished from aragonite. It includes common limestone, chalk, and marble. Called also calc-spar and calcareous spar.
Example Sentences:
(1) The crystallographic orientation of the calcite also appears to be independent of these fibrils.
(2) The calcium carbonates-calcite, aragonite, and vaterite-constitute most of the remainder of the calculi.
(3) Crystallographic analysis of stones from patients with nutritional pancreatitis (NP), as well as alcoholic pancreatitis (AP), revealed that the main constituent was calcite (CaCO3).
(4) Calcite was present in all stones, vaterite in 12%, and a central amorphous material in 30%.
(5) X-ray diffraction showed that calcite (CaCO3) was the major crystalline constituent of the calcareous deposits.
(6) When the doped glasses have been immersed in a physiological solution (199 medium), a film of calcite forms on the glass surface and this modification is related to the type of doping agent used, decisive for close linking between metal supports and the glass.
(7) We suggest that precipitation of calcite in the pancreatic duct occurs as the primary event in the formation of pancreatic calculi and that it may continue until the duct is completely occluded.
(8) 5-7): calcite and quartz are the principal components of the sinters, additional diffuse apatite lines appear in bone samples.
(9) These features are characteristic of sea urchin (Echinoderm) spines which are composed of ornately formed calcite crystals covered by an epithelium.
(10) Its absence in all analyzed invertebrate tissues (including calcitic, aragonitic, and apatitic mineral phases) indicates that matrix protein-bound gamma-carboxyglutamic acid is not obligatory for the calcification process in the invertebrates.
(11) Quantitatively, phosphate is by far the most important inhibitor of calcite precipitation present in saliva, suggesting that inhibition of calcite precipitation by the macromolecules may be of secondary significance.
(12) Plates of calcite (CaCO3) were implanted in rabbit tibiae, and their biocompatibility and bonding ability to bone were studied.
(13) Subsequent increase in diameter of the rod involves the radial development of irregular columns of calcite which arise from the peripheral nodules.
(14) The phenomenon of dissolution and recrystallisation in situ of the calcite can be a trap because it can be a reservoir for micro-organisms.
(15) Synechococcus strain GL24 was isolated from Fayetteville Green Lake, New York, where it has a demonstrated role in the formation of calcitic minerals.
(16) Pancreatic stones are observed in both humans and cattle, and are approximately 95% CaCO3 (calcite) in both species.
(17) Skeletal walls of more than one mineralogy have the magnesium-rich layer (calcite) surrounding the living chamber and the strontium-rich layer (aragonite) on the outside.
(18) Here we report on the ability of a soil bacterium to synthesize calcite in a calcium-stressed environment.
(19) Formation of inner protein nidus in the form of a cobweb is the first stage, then calcite is deposited on this fibrous network as tiny crystals.
(20) The biocompatibility of mammal bone with aragonite and calcite skeletons of aquatic invertebrates (Corals, Molluscs) led us, after animal experimentation, to implant in humans artificial dental roots derived from such invertebrates.