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Because of the way it reacts with air and water, strontium only exists in nature when combined to form minerals. Naturally occurring strontium is stable, but its synthetic isotope Sr-90 is only produced by nuclear fallout. In groundwater strontium behaves chemically much like calcium. At intermediate to acidic pH Sr 2+ is the dominant strontium ...
Naturally occurring strontium is nonradioactive and nontoxic at levels normally found in the environment, but 90 Sr is a radiation hazard. [4] 90 Sr undergoes β − decay with a half-life of 28.79 years and a decay energy of 0.546 MeV distributed to an electron, an antineutrino, and the yttrium isotope 90 Y, which in turn undergoes β − decay with a half-life of 64 hours and a decay energy ...
About 8% by weight of cathode ray tubes is strontium oxide, which has been the major use of strontium since 1970. [3] [4] Color televisions and other devices containing color cathode ray tubes sold in the United States are required by law to use strontium in the faceplate to block X-ray emission (these X-ray emitting TVs are no longer in production).
The alkaline earth metal strontium (38 Sr) has four stable, naturally occurring isotopes: 84 Sr (0.56%), 86 Sr (9.86%), 87 Sr (7.0%) and 88 Sr (82.58%). Its standard atomic weight is 87.62(1). Only 87 Sr is radiogenic ; it is produced by decay from the radioactive alkali metal 87 Rb , which has a half-life of 4.88 × 10 10 years (i.e. more than ...
Strontium-90 has been used in radioisotope thermoelectric generators (RTGs) in the past because of its relatively high power density (0.95 W thermal /g for the metal, 0.46 W thermal /g for the commonly used inert perovskite form Strontium titanate) and because it is easily extracted from spent fuel (both native Strontium metal and Strontium ...
Plus, natural disasters could spread the site's contamination. ... later found the government had conducted a test in 1949 to learn more about how the radioisotope Iodine 131 moved through the air ...
While some radioisotopes, such as strontium-90 (90 Sr) and technetium-99 (99 Tc), are only found on Earth as a result of human activity, and some, like potassium-40 (40 K), are only present due to natural processes, a few isotopes, such as tritium (3 H), result from both natural processes and human activities.
Strontium is naturally deposited in hydroxyapatite, the mineral component of bones and teeth, following its consumption in food and water. [11] Each locale has a unique Sr isotope ratio and, therefore, the ratio found in a bone or enamel sample can be cross referenced against a record of environmental Sr ratios and assigned to a region. [11]