(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.
Feldspar
Definition:
(n.) Alt. of Feldspath
Example Sentences:
(1) The quantitative mineralogical analysis of small samples (less than 20 mg) of china clay has been investigated using x ray diffractometry to determine kaolinite, mica, quartz, and feldspar.
(2) The resulting feldspar-alumina composites were compared for shrinkage then cut and prepared into disc specimens.
(3) The lung dust composition in this case was approximately 43% silicon carbide, 24% aluminium oxide, 2.3% cristobalite, 2.0% quartz, and trace of talc and feldspar.
(4) Quartz, calcite, feldspar, smectite, inter-stratified phases, kaolinite, amphibole, muscovite and dolomite are other contaminating minerals.
(5) The conventional feldspar ceramic is then placed onto this very resistant (more than 580 MPa flexural strength) and exceptionally well adapted framework.
(6) The adhesion of Salmonella typhimurium to the mineral particles quartz, albite, feldspar, and magnetite was shown to correlate with the hydrophobicity of the cell surface as measured by hydrophobic interaction chromatography.
(7) Significant numbers of primary lung tumors, principally adenocarcinomas and adenomas, were seen in the copper slag (p = 0.005 and p = 0.022 for the primary and secondary slags, respectively), in the feldspar (p = 0.007), in the novaculite (p less than 0.001), and in the Min-U-Sil (p less than 0.001) groups when compared to the vehicle control group.
(8) 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).
(9) An application of high-resolution transmission electron microscopy (HRTEM) to the study of two types of dislocations in potassium feldspars (K-feldspars) is shown here.
(10) Eighty-eight were of mineral origin, mainly quartz and feldspar, and it is believed that the great majority were submitted for secondary gain or for psychiatric reasons.
(11) Feldspar-alumina composites shrank approximately 30%; shrinkage of 15-20% occurred only in composites involving spherical alumina (average particle size 5.4 microns).
(12) Kaolinite, talc, mica, feldspars, and crystalline silica comprised the majority of particles of both groups.
(13) If the soil where potatoes are grown contains feldspars, sprout inhibition treatment with 100-200-Gy doses can also be detected for up to one year, using the 90-250 degrees C low-temperature part of the TL spectrum for evaluation.
(14) Composites of feldspar and spherical alumina were observed to be stronger than those of feldspar and nonspherical alumina.
(15) The major reaction seen in both the feldspar- and the novaculite-treated rats was a granulomatous inflammation with varying degrees of fibrosis associated with the granulomas.
(16) A 140% increase in the breaking strength of Keradens facings may be achieved by ion exchange, i.e., by substitution of the small sodium ions in soda feldspar by the larger potassium ions, which is done by melting the soda feldspar with potassium nitrate.
(17) The rare earths were added to a potassium feldspar glass host and emission spectra were measured.
(18) Exposure to mica is usually associated with exposure to other minerals such as quartz and feldspar.
(19) Quartz and feldspar were determined direct from prepared calibration graphs.
(20) The degradability of DNA adsorbed to minor mineral fractions (feldspar and heavy minerals) of the sand differed from that of quartz-adsorbed DNA.