radioactive substance

基本解釋

The United Nations agency says they do not protect against external radiation, or against any other radioactive substance.
這個(gè)聯(lián)合國(guó)機(jī)構(gòu)表示，這些藥片不能防止外部輻射，也不能抵御任何其他的放射性物質(zhì)。
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(bào)官員亞歷山大·利特維年科在2006年被一種稀有輻射性物質(zhì)钚投毒暗殺。
The wife of a Russian spy who was poisoned with a radioactive substance is now tested positive for it.
俄羅斯特工威克多·利特維年科因放射性物質(zhì)中毒，現(xiàn)在其妻放射性物質(zhì)測(cè)試顯陽(yáng)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