The early Earth contained abundant radioactive materials.

早期地球含有丰富的放射性物质。

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Radioactive materials are composed of atoms that are unstable.

放射性物质由很多不稳定原子构成。

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Radioactive materials tend to be released from a damaged nuclear plant in a certain pattern.

受损核电站在释出放射性物质时往往会遵循同一种模式。

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Days after signing a deal to cut U.S.and Russian nuclear arsenals, President Obama hopes to strengthen global resolve to safeguard nuclear stockpiles and keep radioactive materials out of the hands of terrorist groups and rogue states.

VOA: standard.2010.04.11

As carefully as people work with radioactivity here, and using often much, much safer radioactive materials than radium bromide, and using them, and special hoods, and having special procedures, they still do a lot of checking with these Geiger counters to make sure everything's safe.

虽然在这里人们,用放射性物质都非常的小心，而且通常用的材料放射性,都比溴化镭要小得多，并且用的时候,都用特殊的容器,特殊的操作过程,但我们平时仍会用。

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She has two Nobel Prizes for her work in radioactive materials.

如何工作方面是绝对的领军人物。

麻省理工公开课 - 化学原理课程节选

Her work will focus on studying the fate of toxic and radioactive materials in the environment.

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Suppose, however, that the rockets carried nuclear payloads, or that suicide bombers had access to radioactive materials.

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Radioactive materials used in nuclear power generation must be isolated from human or environmental contact for thousands of years.

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