A number of atmospheric nuclear tests took place from 1945 to 1980 . radioactive particulates produced in the explosions dispersed into the atmosphere by the winds and some of them deposited onto the ground 在一九四五年至一九八零年期间，世界各地进行了多次大气核试爆，所产生的放射性尘埃随风扩散，部份沉降到地上。
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A number of atmospheric nuclear tests took place from 1945 to 1980 . radioactive particulates produced in the explosions dispersed into the atmosphere by the winds and some of them deposited onto the ground . deposition of these radioactive materials increased the level of artificial radiation in the environment 在一九四五年至一九八零年期间，世界各地进行了多次大气核试爆，所产生的放射性尘埃随风扩散，部份沉降到地上。这些放射性沉积物为我们自然环境增加了额外的人工辐射。
