radioactive material

基本解释

But it depends on the depth of the radioactive material.
但是这取决于放射性物质的厚度。
Professor Bushberg says removing the topsoil might make the land safe for use. But it depends on the depth of the radioactive material.
布希柏格教授说，移除表层土壤可以保证土地的使用安全，但这取决于放射性物质渗入的深度。
Once you start damaging the core, you are then releasing radioactive material into the coolant and thereby increasing the chances that something travels outside the reactor.
一旦你开始破坏核心，你就会向冷却剂中释放放射性物质，从而提高了这些物质泄露到反应堆外的危险。

But it depends on the depth of the radioactive material.
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."

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