refrain from harvesting after radioactive material fallout.

有放射性物质落下时不要进行采收。

youdao

Irradiation leaves no traces of radioactive material in food.

辐照会残留一些不明的放射性物质在食物里面。

youdao

The pressure vessel is the third barrier to radioactive material release.

高压管是放射材料的第三道防护。

youdao

But it depends on the depth of the radioactive material.

VOA: special.2011.03.29

We have 266 ping-pong balls, and we need someone, hopefully you, to be some radioactive material that are going to be emitting these ping-pong balls. And when the time comes, in just a minute, I'll ask the TAs to come down and hand these out very quickly to you, so we can do this experiment.

你们有些人那天，看到我在办公室数乒乓球，我们需要几个人,希望是你,来作为放射材料，放射这些乒乓球,等会我会让助教,把这些球发给你们。

麻省理工公开课 - 化学原理课程节选

So,yes,there is a threat particularly of the use of radioactive material, although we have no specific evidence indicating any capability at this time."

VOA: standard.2009.05.01

In fact, standards for NORM (naturally occurring radioactive material) have been observed for years.

FORBES: Don't Be Swayed By Faucets On Fire And Other Anti-Fracking Propaganda

Even during the process we should never release any radioactive material into the surrounding environment.

BBC: Fukushima disaster: Long road to nuclear clean-up

Increased concentrations of radioactive material were found in milk and vegetables in the area.

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