When Stevenson followed the carbon-14 trail back in time, he found carbon-14 levels change with the intensity of solar burning.

当史蒂文森依据碳-14的痕迹追溯过去时，他发现碳-14的含量随着太阳燃烧的强度而变化。

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The particles interfere with the formation of carbon-14 on earth.

这些粒子干扰了地球上碳-14的形成。

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Doctors Stevenson is analyzing one element—carbon-14 in ring from both living and dead trees.

史蒂文森博士正在分析一种元素——活树和死树年轮中的碳-14。

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And carbon 14, 6 again and it has 8, and it is found in vanishingly small amounts, 10 10 to the minus 12 or part per trillion.

碳14，6个质子，8个中子，它的存在是非常微小的，几乎趋于零，万亿分之。

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。

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The neutrons smashed into nitrogen and created much more carbon 14 than normal.

FORBES: Magazine Article

As mentioned, carbon-14 is radioactive, and as the Sun becomes more active (interglacial times) so does the amount of the radioactive carbon-14.

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They were able to determine that he was born between 1955 and 1960 by looking at the carbon 14 in the victim's teeth.

FORBES: Magazine Article