We’ve heard about radiation from the damaged nuclear reactors in Japan reaching American shores. Experts say so far there is no reason to worry, and point out that we meet radiation every day. Where and how? NPR’s Renee Montagne posed that question to Peter Caracappa, a radiation safety officer and professor of nuclear engineering.
MONTAGNE: How many things emit radiation?
Dr CARACAPPA: Well, radiation and radioactive material is a part of nature. So everything that’s living has some amount of radiation ing from it—a very small amout. Plus there’s radiation in the ground and the air.
So the extremes are uranium in the soil to bananas?
Yes.
By the way, why do bananas have radiation?
Bananas have a lot of potassium(钾). And a small amount of potassium naturally is called potassium 40, which is radioactive
What’s the difference between radiation that’s harmful and not harmful?
Well, the term radiation can apply to a lot of different things. But the harmful radiation is ionizing(离子)radiation. It has enough energy that it can make chemical changes in material. We could get ionizing radiation from an X-ray, for example. It’s the kind of radiation that causes cancer.
The broader definition of radiation includes a lot of things that we call non-ionizing radiation. That includes everything like radio waves and visible light and your microwave.
So what then is the largest contributor of ionizing radiation?
For the natural sources of ionizing radiation, actually the biggest chunk of that tends to e from radon(氡), which is a radioactive material that is present in the air. It can bee a concern when it builds up in low-lying areas of homes like basements.
Would it be fair to say that most people do not need to worry about the danger of being exposed to radiation?
I would say that the everyday exposure to radioation that we meet contributes an extremely tiny risk to our life or to our health pared to all of the other risks that we meet in our day-to-day life.
【小题1】We can infer from the first paragraph that radiation is .A．rareB．powerfulC．dangerousD．mon【小题2】The passage may be .A．an interviewB．an argumentC．a talk show programD．a science report【小题3】Whether radiation is harmful or not depends on .A．whether it has a small amount of potassiumB．whether it changes chemical in materials.C．whether it has energy to change materialsD．whether it is visible in life【小题4】The purpose of writing this passage is to .A．advise on how to protect us from radiation B．analyze what causes radiation in daily lifeC．warn people of the danger of radiationD．expect people not to fear everyday radiationD
网友回答
(答案→)D
解析：文章通过一次采访报道介绍了放射性的辐射是很普遍的现象，人们没有必要过于担心。
【小题1】D 推理题。根据第一段第二行Experts say so far there is no reason to worry, and point out that we meet radiation every day.说明在我们的生活中放射性是很常见的事情，故D正确。
【小题2】A 推理题。根据第一段最后两行NPR’s Renee Montagne posed that question to Peter Caracappa, a radiation safety officer and professor of nuclear engineering.说明Montagne在采访一名核方面的教授，故这是一次采访活动，A正确。
【小题3】B 推理题。根据倒数第六段But the harmful radiation is ionizing(离子)radiation. It has enough energy that it can make chemical changes in material.说明当这样的离子有足够的能量产生化学反应的时候，就对人体有害了，故B正确。
【小题4】D 主旨大意题。根据文章的主题段第一段可知在日常生活中放射性随处可见，是一种很普遍的现象，人们没有必要过去担心。故D正确。