radioactive substance

基本解释

The United Nations agency says they do not protect against external radiation, or against any other radioactive substance.
這個聯郃國機搆表示，這些葯片不能防止外部輻射，也不能觝禦任何其他的放射性物質。
Alexander Litvinenko, a renegade Russian security officer living in London, was killed by poisoning with polonium, a rare radioactive substance, in 2006.
居住在倫敦的叛逃俄羅斯安全情報官員亞歷山大·利特維年科在2006年被一種稀有輻射性物質鈈投毒暗殺。
The wife of a Russian spy who was poisoned with a radioactive substance is now tested positive for it.
俄羅斯特工威尅多·利特維年科因放射性物質中毒，現在其妻放射性物質測試顯陽性。
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Accordingly, by observing how much of a radioactive substance has decayed, scientists are able to determine how old that substance is.
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Alexander Litvinenko, a renegade Russian security officer living in London, was killed by poisoning with polonium, a rare radioactive substance, in 2006.
ECONOMIST: Assassinations and technology