(n.) Silicon dioxide, SiO/. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tasteless, inodorous powder.
Example Sentences:
(1) We have previously shown that intratracheally instilled silica (quartz) produces both morphologic evidence of emphysema and small-airway changes, and functional evidence of airflow obstruction.
(2) In the German Democratic Republic, patients with scleroderma and history of long term silica exposure are recognized as patients with occupational disease even though pneumoconiosis is not clearly demonstrated on X-ray film.
(3) Human gingival fibroblasts were allowed to attach and spread on bio-glasses for 1-72 h. Unreactive silica glass and cell culture polystyrene served as controls.
(4) The ADAM derivative of carnitine was separated from decomposition products of the reagent and related compounds such as amino acid derivatives on a silica gel column eluted with methanol-5% aqueous SDS-phosphoric acid (990:10:1).
(5) The deactivated columns had the residual silanols on the silica gel chemically inactivated to reduce the interaction with basic groups or analytes.
(6) We have investigated some of the factors which affect the retention times of these substances in reversed-phase HPLC on columns of 5-micron octadecylsilyl silica.
(7) The corresponding hydrides, mono-n-butyltin hydride, di-n-butyltin hydride, tri-n-butyltin hydride, monophenyltin hydride, diphenyltin hydride triphenyltin hydride, are detected by electron-capture gas chromatography after clean-up by silica gel column chromatography.
(8) The length of the hydrocarbon chains of the surface-modified silica supports had no significant influence on the selectivity.
(9) A novel type of ion exchanger was prepared by multipoint covalent binding of polystyrene chains onto the surface of porous silica followed by polymer-analogous modification of the bonded layer.
(10) The analytes were rapidly separated on an affinity column packed with phenylboronate-bonded silica.
(11) Using thin layer chromatography on fluorescent silica gel plates, 5 indoles were identified and 6 unknown substances isolated from the pineal incubate and from both extracts.
(12) Our results clearly demonstrate that capillary GC analysis of amino acids using fused silica bonded-phase columns provides data with good precision and in general excellent agreement with ion-exchange analyses.
(13) Free haem itself was bound to the silica column but could be released by globin.
(14) The methanol-ammonia (20:1) and chloroform-methanol-ammonia (2:2:1) systems, used with silica-gel plates, are the most promising for rapid preliminary screening of tuna fish extracts for histamine.
(15) The presence of Ca2+ in silica gel is responsible for this improved yield of prostaglandin as the divalent metal ion stabilized prostaglandin synthetase activity in a remarkable way.
(16) Silica accumulated linearly in the mediastinal lymph nodes and thymus for several months after cessation of exposure, while negligible amounts were found in kidney, spleen, liver, and blood.
(17) Methods employing electroosmotic flow in an untreated silica capillary were found to provide, at best, only partial resolution of the 23 fragments in a 1-kbp DNA ladder.
(18) The galactose lipid was isolated by column chromatography on DEAE-cellulose and silica gel.
(19) Adsorption experiments were performed by combining virus and silica in 0.1-ionic-strength buffers of pH 4.0, 6.4, and 8.5.
(20) The extracts are analyzed via a gas chromatograph equipped with a DB-1301 widebore fused-silica capillary column and an electron capture detector.
Zircon
Definition:
(n.) A mineral occurring in tetragonal crystals, usually of a brown or gray color. It consists of silica and zirconia. A red variety, used as a gem, is called hyacinth. Colorless, pale-yellow or smoky-brown varieties from Ceylon are called jargon.
Example Sentences:
(1) Modern ultrasonic transducers mainly employ lead zirconate titanate (PZT) but vinylidene fluoride trifluoroethylene copolymer (P (VDF-TrPE)) is becoming more competitive.
(2) The application of zircon (ZrSiO4) that has high refractoriness, high thermal conductivity and a low coefficient of thermal expansion, to quick casting investment was studied.
(3) Disk-shaped implants of spinel, alumina, mullite, zircon, a cast Co-Cr-Mo alloy, and ultra-high molecular weight polyethylene (UHMWPE), were implanted in the paraspinalis muscle of 12 adult, male, white New Zealand rabbits.
(4) Some samples of red mud, phosphogypsum, zircon products and fly ash did show higher levels of radioactivity than would be acceptable on the basis of a criterion formula for gamma-ray activity suggested for use in some OECD countries.
(5) An Ontario plant with 101 workers, producing and using the ceramic compound lead titanate zirconate (LTZ), was investigated.
(6) The acoustic emission from cavitation in the field of an extracorporeal shock wave lithotripter has been studied using a lead zirconate titanate piezoceramic (PC4) hydrophone in the form of a 100-mm diameter focused bowl of 120-mm focal length.
(7) Further heating changed surface structure and led to zircon production in the zirconia fibres.
(8) 2) Dainainvest (Ohara) mainly containing zircon indicated the reduction in surface roughness due to coating.
(9) Small casting of pure titanium and K-metal could be done successfully by the quick casting method using the zircon-phosphoric acid investments.
(10) Results were as follows: 1) The refractory compositions of seven commercialized coating materials were composed of alpha-quartz (SiO2), zircon (ZrSiO4) and zirconium oxide (ZrO2).
(11) The transducer usually consists of a piezoelectric crystal composed of such ceramic materials as barium titanate, lead titanate, zirconate, or lead metaniobate.
(12) Working processes using zircon sand in a factory producing refractory material were studied from the point of view of radiation protection.
(13) Zircon sand contains high concentrations of natural radionuclides and is a typical example of an enhanced source.
(14) Although zircon was slightly observed on the cast surface, the product of reaction was not detected.
(15) Formulation of zircon slurry for coating was zircon flower #600 30%, zircon flower #350 10%, and zircon sand CP 60%, and that for sanding was zircon flower #200.
(16) Immediately after coating with zircon slurry, the coating layer was dried, sintered and dewaxed by thermal shock.
(17) A new family of materials consisting of lead lanthanium zirconate titanate (PLZT) has evolved from recent advances in ferroelectric ceramics.
(18) We used a flat or focused, 10 mm diameter transducer made of lead zirconate-titanate with a resonant frequency of 2 or 3 MHz at a repetition rate of 3.6 kHz.
(19) 3) Liquid investment (Nobilium) and Paint investment (Shofu) having about equal amounts of alpha-quartz and zircon showed as reduction in surface roughness as Dainainvest.
(20) Various zircon powders and phosphoric acid solutions were tested with respect to the higher thermal shock resistance.