Cesium-137, with a half-life of 30 years, is another dangerous substance emitted in a full-scale nuclear meltdown.

核反应堆完全熔解后，会释放出另一种危险物质铯- 137。铯- 137的半衰期为30年。

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Full size substance specimen tests shall not be replaced by mechanical properties tests with small size specimen.

说明了全尺寸实体试件试验具有很高的实用价值，是无法用小试样性能试验替代的。

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Urban authorities in Britain have their hands full these days chasing explosives, yet some of them seem to have an obsession with a less dangerous substance: chicle.

FORBES: Gobstoppers