They had been interested in thorium -- a radioactive element that can fuel nuclear reactors but not be processed into weapons.

VOA: special.2010.10.15

Alpha particles are these helium nuclei, and they are the result of radioactive decay.

阿尔法粒子是氦核，它们是放射性衰变的产物。

麻省理工公开课 - 固态化学导论课程节选

4 And then there are the last four, carbon 14, which is a radioactive form.

然后，还有碳，以放射性形式存在。

麻省理工公开课 - 固态化学导论课程节选

Radioactive particles travel in the wind and get absorbed into soil with the help of rain and snow.

VOA: special.2011.03.29

Suppose we've got some sort of radioactive atom, which has a certain chance of decaying.

假定我们有某种放射性原子,它们以一定的几率衰变

耶鲁公开课 - 死亡课程节选

World War Two ended. Enrico Fermi had been the first to use a neutron to produce the radioactive change of one element to another.

VOA: special.2009.06.14

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。

麻省理工公开课 - 化学原理课程节选

On Tuesday, Chinese officials reported low levels of radioactive iodine-131 in areas of southeastern China.

VOA: special.2011.03.30

This label is DNA that might be made radioactive or made fluorescent, and it has a base pair sequence that is from some other region of the gene that you're interested in.

这种标签就是具有放射性,或者荧光性的DNA,它有一个取自于,你感兴趣的那段基因上,其他位置的碱基对序列

耶鲁公开课 - 生物医学工程探索课程节选

But people exposed to high levels of radioactive iodine can get thyroid cancer.

VOA: special.2011.03.30

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

Some medicines,like Prussian blue pills, can help expel radioactive elements from the body.

VOA: special.2011.03.30

Because it is heavy you expect it is radioactive.

因为它的重，所以你想它应该是放射性元素。

麻省理工公开课 - 固态化学导论课程节选

It was an attempt to cool the highly radioactive fuel rods from overheating.

VOA: special.2011.03.19

And, he worked for a little less than 10 years at McGill where he did more work on these particles that radiate from radioactive elements.

他在McGill工作了将近10年,在McGill期间做了更多的,关于放射性元素的放射性的工作。

麻省理工公开课 - 固态化学导论课程节选

The first HEPA filters removed radioactive particles from the air.

VOA: special.2009.07.14

For those of you don't know what that is it's simply an instrument that counts radioactive particles in the air, and MIT now that you're at MIT, you'll all have a chance to see one first hand if you're ever in any of the labs, especially in the chemistry or bio labs.

不知道它是什么,它就是一个简单的,计算在空气中放射粒子数目的仪器,你们现在来了，如果你们在实验室里工作的话,尤其是化学和生物实验室，你们有很多机会亲手用到它。

麻省理工公开课 - 化学原理课程节选

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

He won for producing new radioactive elements beyond uranium.

VOA: special.2009.06.14

The pills flood the thyroid gland with non-radioactive iodine.

VOA: special.2011.03.30

But radioactive waste is a serious unresolved issue.

VOA: special.2011.03.18

Florbetapir is a radioactive coloring agent.

VOA: special.2011.02.08

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

But the acquisition of radioactive material for a so-called 'dirty bomb,' which is radioactive material that is dispersed with a conventional explosive device, that is not that challenging.

VOA: standard.2009.05.01

"Something else, which we hope does not happen very often, but which happens from time to time are the accidents which can release huge amounts of chemicals or radioactive-during Chernobyl, the radioactive things.

VOA: standard.2009.03.23

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