Potential Energy Source-Helium-3托福聽力原文翻譯及問題答案
2023-06-20 14:34:38 來源:中國教育在線
Potential Energy Source-Helium-3托福聽力原文翻譯及問題答案
一、Potential Energy Source-Helium-3托福聽力原文:
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托福聽力中文翻譯:
旁白:請聽環(huán)境科學(xué)課的一部分講座。男教授:上周,當(dāng)我們討論了隨著世界人口持續(xù)增長,我們將面臨的嚴(yán)重能源挑戰(zhàn),我們更加強調(diào)我們有限的化石燃料供應(yīng),特別是天然氣和石油,也許這并不完全是厄運。在許多領(lǐng)域,科學(xué)家們正在“跳出框框思考”,試圖為能源問題提出不同尋常的、新穎的解決方案。這并不是說肯定的結(jié)果是不可避免的,但是……好吧,讓我們來看看其中一個創(chuàng)造性的想法,涉及氣體氦-3。氦-3是氦的同位素,在實際能源應(yīng)用中具有巨大的潛力。記住,啊,同位素是一種化學(xué)元素,它的原子核中有相同數(shù)量的質(zhì)子,但中子的數(shù)量不同。地球上最常見的氦同位素是氦-4,它沒有任何已知或潛在的能源用途。相比之下,氦-3極為罕見。地球上沒有太多。另外,嗯,太陽系中氦-3的主要來源是太陽風(fēng)-一股致命的輻射和粒子流從太陽和地球磁場中涌出,幸運的是,阻止了風(fēng)到達(dá)我們。
為什么氦-3如此令人興奮?
嗯,看來可以肯定的是,月球上有大量的氦-3。由于月球沒有磁場,太陽風(fēng)肯定已經(jīng)在那里沉積了數(shù)十億年的氦-3。事實上,阿波羅宇航員已經(jīng)在月球塵埃中發(fā)現(xiàn)了它。一些估計認(rèn)為月球表面可能埋有超過100萬噸的氦-3。一噸的能量對于一個擁有一千萬人口的城市來說已經(jīng)足夠一年了。你可以看到,這肯定會解決我們大部分的能源問題。但這怎么可能呢?
我們認(rèn)為氦-3必須用于核聚變反應(yīng)堆。請記住,核聚變反應(yīng)堆與我們現(xiàn)有的核裂變反應(yīng)堆完全不同?;旧?,以核裂變?yōu)閯恿Φ暮穗娬緩脑臃至阎蝎@取能量。而基于核聚變的核電站利用原子聚變時產(chǎn)生的能量。聚變是為恒星提供燃料的同一核反應(yīng),正如你所知,它產(chǎn)生了不可估量的能量。
研究人員已經(jīng)確定兩種氫同位素是核聚變電站最有希望的燃料來源。然而,有一個真正的缺點-它們都在聚變反應(yīng)中產(chǎn)生大量放射性物質(zhì)。但是氦-3聚變不會產(chǎn)生放射性物質(zhì)。事實上,一位支持者表示,你可以在城市中心安全地建造一座氦-3發(fā)電廠!
一個干凈、安全的能源聽起來太好了,不是嗎?當(dāng)然,這都是理論性的。還有一些問題需要解決。
一方面,盡管經(jīng)過幾十年的研究和開發(fā),我們?nèi)匀粵]有建立一個核聚變工廠。一個經(jīng)常聽到的關(guān)于核聚變的笑話是,核聚變工廠離建成只有幾十年的時間了。核聚變研究仍在進(jìn)行中,事實上,與以往一樣強大,但我們?nèi)匀粵]有一個完整的核聚變工廠。還有一個相當(dāng)大的后勤問題如何使氦-3離開月球。由于氦-3在月球表面的分布非常分散,因此挖掘這些物質(zhì)是一項挑戰(zhàn)。據(jù)估計,需要將100萬噸月球土壤加熱到800攝氏度,才能產(chǎn)生70噸氦-3氣體。這有點像用勺子挖一個隕石坑來尋找一塊金塊。有點荒謬,對吧?有一個陣營認(rèn)為提取氦-3氣體需要比氣體本身提供更多的能量。因此有人擔(dān)心,但考慮到可能性的誘惑和我們能源困難的緊迫性,氦-3可能成為未來月球探索的重要驅(qū)動力。如果解決了眾多挑戰(zhàn),而不僅僅是我們討論過的挑戰(zhàn),它肯定會緩解對化石燃料的需求壓力。
三、Potential Energy Source-Helium-3托福聽力問題:
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托福聽力答案:
A1:正確答案:C
A2:正確答案:D
A3:正確答案:AB
A4:正確答案:D
A5:正確答案:C
A6:正確答案:A
>> 雅思 托福 免費測試、量身規(guī)劃、讓英語學(xué)習(xí)不再困難<<