Hormonal contraceptives (the pill, the patch, and the vaginal ring) all contain a small amount of man-made estrogen and progestin hormones. These hormones work to inhibit the body's natural cyclical hormones to prevent pregnancy. Pregnancy is prevented by a combination of factors.
Definition of STRONTIUM 90. : a heavy radioactive isotope of strontium of mass number 90 that has a half-life of 29 years, that is present in nuclear waste and fallout, and that is hazardous because like calcium it can be assimilated in biological processes and deposited in the bones of human beings and animals.See strontium 90 defined for kids. a heavy radioactive isotope of strontium having the mass number 90 that is present in the fallout from nuclear explosions and is hazardous because like calcium it can be assimilated in biological processes and deposited in the bones of human beings and animalsâcalled also radiostrontium.
In the industrial sector, strontium chloride is uses as a precursor chemical to produce other types of strontium compounds used as brazing fluxes and phosphor coatings. It is also used as a corrosion inhibitor in aluminum alloys as the compound strontium chromate, and, since it burns with a bright red color, strontium and fireworks go hand in hand.