Sentences with phrase «radioactivity halves»
The half - lives (the period in which radioactivity halves) of these atoms range up to tens of thousands of years, a feature that led U.S. government regulators to require that the planned high - level nuclear waste repository at Yucca Mountain in Nevada isolate spent fuel for over 10,000 years.
https://www.scientificamerican.com/ Not exact matches
The only previously known radioactive carbon isotope at the time was carbon - 11, which had a half - life of only 21 minutes (half the isotope's radioactivity will decay in that time).
Overall, the tanks hold every element in the periodic table, including half a ton of plutonium, various uranium isotopes and at least 44 other radionuclides — containing a total of about 176 million curies of radioactivity.
So far, most of the radioactivity has come from iodine - 131 which has a half - life of eight days.
Strontium - 90 and cesium - 137 have half - lives of 30 years — half the radioactivity will decay in 30 years.