(n.) An earth of a white color resembling lime in appearance, and baryta in many of its properties. It is an oxide of the metal strontium.
Example Sentences:
Strontium
Definition:
(n.) A metallic element of the calcium group, always naturally occurring combined, as in the minerals strontianite, celestite, etc. It is isolated as a yellowish metal, somewhat malleable but harder than calcium. It is chiefly employed (as in the nitrate) to color pyrotechnic flames red. Symbol Sr. Atomic weight 87.3.
(n.) A radioactive isotope of strontium produced by certain nuclear reactions, and constituting one of the prominent harmful components of radioactive fallout from nuclear explosions; also called radiostrontium. It has a half-life of 28 years.
Example Sentences:
(1) Specimens of human bone from the site exhibited lower strontium levels and strontium-to-calcium ratios than deer specimens from the same site, reinforcing paleodemographic evidence that the human populations that inhabited this site included substantial amounts of meat in their diets.
(2) Revascularisation was evaluated with radioactive microspheres; formation of new bone was assessed by incorporation of strontium, and resorption was assessed by measuring the reduction of graft weight.
(3) Compared with the transected control group, resection decreased strontium absorption per unit weight of mucosa (specific absorption) in the proximal segment.
(4) Human spermatozoa incubated in a strontium- or lanthanum-based medium, or T6 + 10% maternal human serum (HS) supplemented with 12 mM 8-bromo cyclic guanosine 3,5'-monophosphate and 10 mM imidazole for a 4-hour period before transfer to fresh T6 + 10% HS for a further 6 hours, demonstrated a significant increase (P less than 0.05) in acrosomal loss compared with T6 + 10% HS for a total 10-hour incubation.
(5) Concentration factors of strontium-90 in aquatic organisms and substrates are higher in a dystrophic lake than in the other types.
(6) In the absence of calcium, other divalent cations such as magnesium, strontium, or manganese were not efficient substitutes for calcium.
(7) A similar effect was obtained by strontium, but magnesium was ineffective.4.
(8) The predicted fallout of strontium-90 in 1970 is less than 1 percent of that during the peak year 1963.
(9) The decontamination of strontium was checked by applying non-dispersive fluorescence X-ray analysis using 133Ba as irradiating source.
(10) Strontium ions, added to a calcium-deficient bathing solution, were shown to attenuate the increased 45Ca uptake by the lens.
(11) Results are presented to show that calcium and strontium act at the same site but strontium is a more sensitive probe for that site.
(12) The elements added to increase radiopacity in the composite materials are barium, strontium, zinc, zirconium, and ytterbium.
(13) Heat-induced release of dipicolinic acid occurred much faster with barium and strontium spores than with calcium spores.
(14) Annual dose rates of 27 millirads to bone and 4 millirads to the whole body correspond to the highest average concentrations of strontium-90 and cesium-137 so far observed.
(15) Strontium (2.5 mM) significantly attenuated the response to CCK-OP and bethanechol, but not to KCl.
(16) Strontium can replace calcium in a number of physiological and biochemical processes.
(17) A high percentage of the strontium retained during both oral and intravenous administration was excreted in 30 days after the discontinuation of the strontium administration and there was no evidence of long term retention.
(18) Enhanced HR with strontium was greater with basophils from normal subjects than from subjects with allergic rhinitis.
(19) In vascular smooth muscle that does not contract spontaneously, similar deposits of strontium were only seen if the muscle was depolarized during or glycerinated before exposure to the strontium-containing solution.
(20) The results of a study of 975 pterygia treated surgically and immediately with Strontium 90 are presented.