Potential Energy Source-Helium-3托福听力原文翻译及问题答案

Potential Energy Source-Helium-3托福听力原文翻译及问题答案

一、Potential Energy Source-Helium-3托福听力原文：

NARRATOR:Listen to part of a lecture in an environmental science class.MALE PROFESSOR:Now last week,when we discussed the serious energy challenges we're going to face as the world's population continues to grow and we place more stress on our finite supply of fossil fuels—especially natural gas and oil—well,maybe it's not all doom and gloom.In a number of areas,scientists are"thinking outside the box"and trying to come up with unusual,uh,novel solutions to the energy question.Not that a positive outcome is inevitable by any means,but...Well,let's take a look at one of these creative ideas,involving the gas helium-3.Helium-3 is an isotope of helium that has tremendous potential for use in practical energy applications.Remember,ah,an isotope is a form of a chemical element that has the same number of protons in its atomic nucleus but a different number of neutrons.The most common isotope of helium on Earth is helium-4,which does not have any known or potential uses as an energy source.Helium-3,in comparison,is extremely rare.There isn't very much of it on Earth.plus the,uh—well the main source of helium-3 in our solar system is solar wind—a stream of lethal radiation and particles pouring off of the Sun—and Earth's magnetic field fortunately prevents that wind from reaching us.

So why is helium-3 so exciting?

Well,it seems a sure bet that helium-3 is available in abundant quantities on the moon.Since the moon doesn't have a magnetic field,the solar wind must have been depositing helium-3 there for billions of years.In fact,Apollo astronauts have already discovered it in the moon's dust.Some estimates hold that there may be over a million tons of helium-3 buried on the lunar surface.And one ton is more than enough energy for a city of ten million people for a whole year.So you can see,this would certainly solve most of our energy problems.But how could this be possible?

Well,we think helium-3 would have to be used in nuclear fusion reactors.Keep in mind that a nuclear fusion reactor is completely different from our existing nuclear fission reactors.Basically a nuclear plant powered by nuclear fission derives its energy from the splitting of atoms.While a plant based on nuclear fusion utilizes the energy produced when atoms are fused together.Fusion is the same nuclear reaction that fuels stars,which as you know,produces unfathomable amounts of energy.

Researchers have identified two isotopes of hydrogen as the most promising fuel sources for fusion power plants.However,there is a real drawback.—they both produce a large amount of radioactive material in a fusion reaction.But helium-3 fusion produces no radioactive material.In fact,one proponent stated you could safely build a helium-3 power plant in the middle of a city!

A clean,safe source of power almost sounds too good to be true,doesn't it?Well,of course,this is all very theoretical.And there are issues that have to be addressed.

For one thing,we still haven't created a single nuclear fusion plant despite decades of research and development.An often heard joke about fusion is that a nuclear fusion plant has been"just decades away"from being created for several decades now.Nuclear fusion research is still ongoing,as strong as ever,in fact,but we still don't have a full-scale fusion plant to point to.And there's a rather big logistical problem as well.:how to get the helium-3 off the Moon.Digging the stuff up is challenging because the distribution of helium-3 is so diffused across the lunar surface.One estimate is that you'd need to heat a million tons of lunar soil to about 800 degrees Celsius to yield about 70 tons of helium-3 gas.It's kind of liking digging out a crater with a spoon to find the single nugget of gold.Kind of ridiculous,right?There's a camp that believes it'll take more energy to extract helium-3 gas than the gas itself would provide.So there are concerns,but given the lure of the possibilities and the pressing nature of our energy difficulties,it's possible that helium-3 could be a significant driver of future exploration of the moon..And it certainly could ease the pressure on the demand for fossil fuels—if and when the numerous challenges—and not just the ones we've talked about—are solved.

二、Potential Energy Source-Helium-3托福听力中文翻译：

旁白：请听环境科学课的一部分讲座。男教授：上周，当我们讨论了随着世界人口持续增长，我们将面临的严重能源挑战，我们更加强调我们有限的化石燃料供应，特别是天然气和石油，也许这并不完全是厄运。在许多领域，科学家们正在“跳出框框思考”，试图为能源问题提出不同寻常的、新颖的解决方案。这并不是说肯定的结果是不可避免的，但是……好吧，让我们来看看其中一个创造性的想法，涉及气体氦-3。氦-3是氦的同位素，在实际能源应用中具有巨大的潜力。记住，啊，同位素是一种化学元素，它的原子核中有相同数量的质子，但中子的数量不同。地球上最常见的氦同位素是氦-4，它没有任何已知或潜在的能源用途。相比之下，氦-3极为罕见。地球上没有太多。另外，嗯，太阳系中氦-3的主要来源是太阳风-一股致命的辐射和粒子流从太阳和地球磁场中涌出，幸运的是，阻止了风到达我们。

为什么氦-3如此令人兴奋？

嗯，看来可以肯定的是，月球上有大量的氦-3。由于月球没有磁场，太阳风肯定已经在那里沉积了数十亿年的氦-3。事实上，阿波罗宇航员已经在月球尘埃中发现了它。一些估计认为月球表面可能埋有超过100万吨的氦-3。一吨的能量对于一个拥有一千万人口的城市来说已经足够一年了。你可以看到，这肯定会解决我们大部分的能源问题。但这怎么可能呢？

我们认为氦-3必须用于核聚变反应堆。请记住，核聚变反应堆与我们现有的核裂变反应堆完全不同。基本上，以核裂变为动力的核电站从原子分裂中获取能量。而基于核聚变的核电站利用原子聚变时产生的能量。聚变是为恒星提供燃料的同一核反应，正如你所知，它产生了不可估量的能量。

研究人员已经确定两种氢同位素是核聚变电站最有希望的燃料来源。然而，有一个真正的缺点-它们都在聚变反应中产生大量放射性物质。但是氦-3聚变不会产生放射性物质。事实上，一位支持者表示，你可以在城市中心安全地建造一座氦-3发电厂！

一个干净、安全的能源听起来太好了，不是吗？当然，这都是理论性的。还有一些问题需要解决。

一方面，尽管经过几十年的研究和开发，我们仍然没有建立一个核聚变工厂。一个经常听到的关于核聚变的笑话是，核聚变工厂离建成只有几十年的时间了。核聚变研究仍在进行中，事实上，与以往一样强大，但我们仍然没有一个完整的核聚变工厂。还有一个相当大的后勤问题如何使氦-3离开月球。由于氦-3在月球表面的分布非常分散，因此挖掘这些物质是一项挑战。据估计，需要将100万吨月球土壤加热到800摄氏度，才能产生70吨氦-3气体。这有点像用勺子挖一个陨石坑来寻找一块金块。有点荒谬，对吧？有一个阵营认为提取氦-3气体需要比气体本身提供更多的能量。因此有人担心，但考虑到可能性的诱惑和我们能源困难的紧迫性，氦-3可能成为未来月球探索的重要驱动力。如果解决了众多挑战，而不仅仅是我们讨论过的挑战，它肯定会缓解对化石燃料的需求压力。

三、Potential Energy Source-Helium-3托福听力问题：

Q1:1.What is the lecture mainly about?

A.The role of fossil fuels as an energy source in the future

B.Reasons for research into alternative energy sources

C.The feasibility of using a potential energy source

D.Causes of probable future energy problems

Q2:2.Why does the professor mention that the Moon lacks a magnetic field?

A.To point out the danger inherent in mining for helium-3 on the Moon

B.To point out a flaw in the theory that helium-3 can be found on the Moon's surface

C.To explain why it was difficult for astronauts to detect helium-3 on the Moon

D.To explain why it is likely that there are large amounts of helium-3 on the Moon

Q3:3.According to the professor,what potential advantages does helium-3 have as an energy source?[Click on 2 answers.]

A.A relatively small amount of it may provide very large amounts of energy.

B.It is less likely to cause environmental problems than other energy sources are.

C.It can be used in both nuclear fusion and nuclear fission reactors

D.The infrastructure required for it to be used as a fuel source is not complex.

Q4:4.What is the professor's opinion of the potential of helium-3 as an energy source?

A.Mining helium-3 on the Moon will eventually be easy

B.Continuing to extract helium-3 from the Moon is not worthwhile.

C.Helium-3 will probably be a significant energy source within a few years.

D.Using helium-3 on a large scale will not be practical until nuclear fusion reactors are built.

Q5:5.Why does the professor mention digging a crater to find gold?

A.To explain why many scientists are interested in new missions to the Moon

B.To explain why helium-4 is more common on Earth than helium-3

C.To explain why extracting helium-3 from lunar soil may not be practical

D.To explain why scientists have looked for helium-3 in unusual places

Q6:6.What does the professor mean when he says this:

A.Scientists are skeptical about the likelihood of a nuclear fusion plant being built.

B.Scientists are aware that a nuclear fusion plant is about to be built.

C.Scientists have been reluctant to support the building of a nuclear fusion plant.

D.Scientists only started believing in the possibility of nuclear fusion in recent years.

四、Potential Energy Source-Helium-3托福听力答案：

A1:正确答案：C

A2:正确答案：D

A3:正确答案：AB

A4:正确答案：D

A5:正确答案：C

A6:正确答案：A