職稱英語 理工A概括大意與完成句子 字典版

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1、32FJ gong-a 第十一篇The Tiniest Electric Motor in the World1 Scientists recently made public the tiniest electric motor ever built. You could stuff hundreds of them into the period at the end of this sentence. One day a similar engine might power a tiny mechanical doctor that would travel through your b

2、ody to remove your disease. 2 The motor works by shuffling atoms between two molten metal droplets in a carbon nanotube. One droplet is even smaller than the other. When a small electric current is applied to the droplets, atoms slowly get out of the larger droplet and join the smaller one. The smal

3、l droplet grows but never gets as big as the other droplet and eventually bumps into the large droplet. As they touch, the large droplet rapidly sops up the atoms it had previously lost. This quick shift in energy produces a power stroke 3 The technique exploits the fact that surface tension the ten

4、dency of atoms or molecules to resist separating becomes more important at small scales. Surface tension is the same thing that allows some insects to walk on water. 4 Although the amount of energy produced is small 20 microwatts it is quite impressive in relation to the tiny scale of the motor. The

5、 whole setup is less than 200 nanometers on a side, or hundreds of times smaller than the width of a human hair. If it could be scaled up to the size of an automobile engine, it would be 100 million times more powerful than a Toyota Camrys 225 horsepower V6 engine. 5 In 1988, Professor Richard Mulle

6、r and colleagues made the first operating micromotor, which was 100 microns across, or about the thickness of a human hair. In 2003, Zettls group created the first nanoscale motor. In 2006, they built a nanoconveyor, which moves tiny particles along like cars in a factory. 6 Nanotechnology engineers

7、 try to mimic nature, building things atom-by-atom. Among other things, nanomotors could be used in optical circuits to redirect light, a process called optical switching. Futurists envision a day when nanomachines, powered by nanomotors, travel inside your body to find disease and repair damaged ce

8、lls. 練習(xí)： 1Paragraph 2 E The Working Principle of the Nanomotor2Paragraph 4 B A Description of the Nanomotor in Terms of Power and Size3Paragraph 5 D Previous Inventions of Nanoscale Products4Paragraph 6 F Possible Fields of Application in the Future5Doctors envision that the nanomotor would travel t

9、hrough human bodies to A remove disease6Surface tension means the tendency of atoms or molecules to B resist separating7Nanoconveyors could be used to F transport nanoscale objects8Applying a small electric current causes atoms to C shuffle between two molten metal droplets世界上最小的電動(dòng)機(jī)最近科學(xué)家公布了現(xiàn)有的最小的電動(dòng)機(jī)

10、。就是在這句話的句號(hào)里，你也能塞進(jìn)幾百個(gè)這樣的電動(dòng)機(jī)。將來有一天，類似的發(fā)動(dòng)機(jī)也許能夠?yàn)橐粋€(gè)微型機(jī)械醫(yī)生提供動(dòng)力，在人的身體里自由移動(dòng)，治療疾病。 發(fā)動(dòng)機(jī)通過碳納米管中的原子在兩小滴金屬溶液間來回運(yùn)動(dòng)進(jìn)行工作。其中一個(gè)小滴甚至比另一個(gè)還要小。當(dāng)微弱的電流通過時(shí)，大一點(diǎn)的小滴金屬溶液中的原子就會(huì)緩慢逸出，進(jìn)入小一點(diǎn)的小滴。這樣，后者體積不斷增大但絕不會(huì)大到和前者一樣最后，與大一點(diǎn)的小滴金屬溶液相撞。當(dāng)它們接觸時(shí)，大的小滴便奪回它失去的原子。能量這樣迅速地來回運(yùn)動(dòng)就產(chǎn)生一次動(dòng)力沖程。 這項(xiàng)技術(shù)利用了表面張力的原理原子或分子有不愿被分開的傾向這在納米等級(jí)上更加重要。表面張力同樣也使某些昆蟲能在水上行

11、走。 雖然這樣產(chǎn)生的能量很少只有20 微瓦，但與電動(dòng)機(jī)的小等級(jí)相比，功率也是相當(dāng)可現(xiàn)了。整個(gè)裝置一側(cè)的長度不到200納米，比人類一根頭發(fā)的寬度還要小幾百倍。如果納米電動(dòng)機(jī)能按比例放大到汽車發(fā)動(dòng)機(jī)的尺寸，它將會(huì)比豐田凱美瑞的225 馬力的V6 引擎功率還要大1 億倍。 1988 年，理查德烏勒教授和他的同事發(fā)明了第一臺(tái)微型發(fā)動(dòng)機(jī)， 100 微米長，或者說有一根頭發(fā)那么粗。2003 年，澤特爾的小組制造出第一臺(tái)納米級(jí)的發(fā)動(dòng)機(jī)。2006 年，他們又造出了納米傳送帶，能夠像工廠里傳送汽車那樣移動(dòng)極小的粒子。 納米技術(shù)的工程師盡力去模擬自然，用一個(gè)個(gè)原子來制造物體。在這些事物當(dāng)中，納米發(fā)動(dòng)機(jī)能夠被用于光

12、電路來改變光的方向，該過程被稱為光學(xué)轉(zhuǎn)換。未來主義者預(yù)想有一天，被納米發(fā)動(dòng)機(jī)驅(qū)動(dòng)的納米機(jī)器能在人體內(nèi)移動(dòng)，發(fā)現(xiàn)疾病并修復(fù)被破壞的細(xì)胞。第十二篇A Strong Greenhouse Gas1 Methane is a colorless, odorless gas; it is also a potent greenhouse gas, and once released into the atmosphere, it absorbs heat radiating from Earths surface. Thats why methane is a major contributor to

13、the planets increasing temperature rise or global warming. Molecule for molecule, methanes heat-trapping power in the atmosphere is 21 times stronger than carbon dioxide, the most abundant greenhouse gas. 2 With 13 billion cows belching almost constantly around the world (100 million in the U. S. al

14、one), its no surprise that methane released by livestock is one of the chief global sources of the gas. Other prime methane sources: petroleum, drilling, coal mining, solid-waste landfills and wet lands. 3 Greenhouse gases like methane and carbon dioxide make up only a small part of Earths atmospher

15、e, which is 78 percent nitrogen and nearly 21 percent oxygen. And without greenhouse gases to trap the suns heat and warm the planet, life as we know it couldnt exist. But in the last 200 years, human activity that requires burning oil, natural gas, and coal for energy has magnified the greenhouse e

16、ffect. 4 Atmospheric concentrations of methane have more than doubled in the last two centuries. Blame for this often focuses on big industries and gas-guzzling vehicles. But agriculture plays a major role, too. In the past 40 years alone, the global cattle population has doubled. 5 Cows munch mostl

17、y grasses and hay yet they grow big and hefty. Why? Because of the rumen. The rumen holds 160 liters of food and billions of microbes. These microscopic bacteria and break down cellulose and fiber into digestible nutrients. A cow couldnt live without its microbes. As the microbes digest cellulose, t

18、hey release methane. The process occurs in all animals with a rumen (cows, sheep, and goats, for example), and it make them very gassy. Its part of their normal digestion process. When they chew their cud, they regurgitate some food to rechew it, and all this gas comes out. The average cow expels 60

19、0 liters of methane a day. 6 Thats why we say livestock gas is also a major factor of causing the global warming. 練習(xí): 1. Paragraph 1 E Methane as a Strong Greenhouse Gas2. Paragraph 2 F Livestock as a Prime Factor of the Greenhouse Effect3. Paragraph 4 C Agriculture Also Contributes to Increased Con

20、centrations of Methane in the Atmosphere4. Paragraph 5 D Why Livestock Releases Methane5. Methane is to the intensifying greenhouse effect. A one of the major contributors6. Greenhouse gases are indispensable to mankind, but the problem mankind is faced with is B the ever-increasing atmospheric conc

21、entrations of greenhouse gases7. Generally people heap criticism on for the planets temperature rise. F big industries and gas-guzzling vehicles8. Nothing has been mentioned in the passage about E how to cut down the cattle populations一種強(qiáng)烈的溫室氣體甲烷是一種無色無味的氣體，同時(shí)也是一種很強(qiáng)烈的溫室氣體，一旦釋放到空氣中，就會(huì)吸收地球表面散發(fā)的熱量。所以說甲烷

22、是使這個(gè)星球日趨變暖(或叫全球變暖)的一個(gè)主要原因。按分子與分子對(duì)比，甲烷在大氣中吸收熱量的能力是二氧化碳最豐富的溫室氣體的21倍。 由于全世界有130億頭牛幾乎在連續(xù)不斷地打嘀(僅美國就有1億頭)，難怪由牲畜釋放的甲烷成為全球甲烷的主要來源。其他主要的甲烷來源有:石油、鉆井、采煤、固體垃圾以及沼澤地。 甲烷和二氧化碳等溫室氣體只占地球大氣的一小部分，大氣中78%為氯氣，將近21%為氧氣。如果沒有溫室氣體來吸收太陽的熱量，使地球變暖，我們所知道的生命就不會(huì)存在。但在過去的200年里，通過燃燒油、天然氣和煤來獲取能量的人類活動(dòng)加劇了溫室效應(yīng)。在過去的兩個(gè)世紀(jì)里，甲燒在大氣中的濃度增加了一倍多，人

23、們常常將此歸罪于大工業(yè)和汽車。但是，農(nóng)業(yè)在其中也扮演了一個(gè)重要角色。僅在過去40年里，全球牲畜數(shù)量就翻了一番。 牛吃的大部分是草，但卻長得身高體壯。原因何在?在于它們都長有瘤胃。它們的瘤胃可容納160升的食物，養(yǎng)育數(shù)十億的微生物。這些微小的細(xì)菌和原生動(dòng)物可分解纖維素，形成可吸收的營養(yǎng)。沒有這些微生物，牛就無法生存。當(dāng)微生物分解纖維素時(shí)，就會(huì)釋放出甲燒。所有長有瘤胃的動(dòng)物(比如牛、綿羊和山羊)都會(huì)這樣，因此它們經(jīng)常釋放出氣體，這是它們的正常吸收過程的一部分。它們反魚時(shí)，就會(huì)將食物重新咀嚼，于是就釋放出氣體。一般每頭牛每天會(huì)排出600升甲烷。 因此，我們認(rèn)為，牲畜釋放的氣體也是全球變暖的一個(gè)主要因

24、素。第十三篇Face Masks May Not Protect from Super-Flu1 If a super-flu strikes, face masks may not protect you. Whether widespread use of masks will help, or harm, during the next worldwide flu outbreak is a question that researchers are studying furiously. No results have come from their mask research yet

25、. However, the government says people should consider wearing them in certain situations anyway, just in case. 2 But its a question the public keeps asking while the government are making preparations for the next flu pandemic. So the Centers for Disease Control and Prevention (CDC) came up with pre

26、liminary guidelines. We dont want people wearing them everywhere, said the CDC. The overall recommendation really is to avoid exposure. 3 When thats not possible, the guidelines say to consider wearing a simple surgical mask if you are in one of the three following situations. First, youre healthy a

27、nd cant avoid going to a crowded place. Second, youre sick and think you may have close contact with the healthy, such as a family member checking on you. Third, you live with someone whos sick and thus might be in the early stages of infection, but still need to go out. 4 Influenza pandemics can st

28、rike when the easy-to-mutate flu virus shifts to a strain that people never have experienced. Scientists cannot predict when the next pandemic will arrive, although concern is rising that the Asian bird flu might trigger one if it starts spreading easily from person to person. 5 During the flu pande

29、mic, you should protect yourself. Avoid crowds, and avoid close contact with the sick unless you must care for someone. Why arent masks added to this self-protection list? Because they can help trap virus-laden droplets flying through the air with a cough or sneeze. Simple surgical masks only filter

30、 the larger droplets. Besides, the CDC is afraid masks may create a false sense of security. Perhaps someone who should have stayed home would don an ill-fitting mask and hop on the subway instead. 6 Nor does flu only spread through the air. Say someone covers a sneeze with his or her hand, then tou

31、ches a doorknob or subway pole. If you touch that spot next and then put germy hands on your nose or mouth, youve been exposed. Its harder to rub your nose while wearing a mask and so your face may get pretty sweaty under masks. You reach under to wipe that sweat, and may transfer germs caught on th

32、e outside of the mask straight to the nose. These are the problems face masks may create for their users. 7 Whether people should or should not use face masks still remains a question. The general public has to wait patiently for the results of the mask research scientists are still doing. 練習(xí)： 1Para

33、graph 2 D Guidelines on Mask Use2Paragraph 3 C When to Use Face Masks3Paragraph 5 A Reasons for Excluding Masks from the Self-protection List4Paragraph 6 F Danger of Infection through Germy Hands and Masks5The scientists are trying to find out if masks may or may not E help protect people from being

34、 attacked by a flu6The CDC is afraid that the public may A overuse face masks7The public will not know the answer about masks until scientists F announce the results of their mask research8We can infer from the passage that the US authorities B deal with the mask problem seriously口罩也許無法預(yù)防感冒如果一場超級(jí)流感暴

35、發(fā)，口罩也許不能保護(hù)你。在下一次世界性的流感暴發(fā)期間，廣泛使用口罩是否有用還是個(gè)問題，科學(xué)家正認(rèn)真研究該題，但至今還沒有任何結(jié)果。然而，為了以防萬一，政府建議人們?cè)谀承┣闆r下還是應(yīng)當(dāng)考慮佩戴口罩。 但當(dāng)政府為下一次流感流行做準(zhǔn)備時(shí)，公眾仍心存疑問。所以美國疾病控制和預(yù)防中心提出了一些初步指導(dǎo)原則，我們不希望人們到處戴著口罩，他們說，總體上是建議要避免到有流感病毒的場合去。 在無法避免的情況下，指導(dǎo)原則提出，在以下三種情況下應(yīng)考慮佩戴一個(gè)簡易的外科手術(shù)口罩:第一，你很健康但要到一個(gè)人群擁擠的地方;第二，你已經(jīng)生病了但仍要與健康的人接觸，如家庭成員要來看你的病情;第三，與你居住在一起的人已經(jīng)感冒了

36、，也許你已經(jīng)處在傳染的早期階段，但你仍需外出。 當(dāng)易變異的感冒病毒出現(xiàn)人們從未遇到過的新種類時(shí)，全國性的流行性感冒就會(huì)暴發(fā)。如果亞洲的禽流感開始輕易地在人與人之間傳播，就可能會(huì)引起一場這樣的大流行性疾病，雖然人們的憂慮不斷升級(jí)，但科學(xué)家仍無法預(yù)測這樣的大暴發(fā)什么時(shí)候會(huì)出現(xiàn)。 在流感期間，你應(yīng)當(dāng)學(xué)會(huì)自我保護(hù)。避免到人多的地方去，遠(yuǎn)離流感病人，除非你必須照顧病人。為什么不把口罩放入自我保護(hù)的措施中呢?口罩能把咳嗽或是打噴囔飛出的含有病毒的飛沫攔截住。但簡易的外科手術(shù)口罩只能過濾大的飛沫。此外，美國疾病控制和預(yù)防中心擔(dān)心口罩可能會(huì)制造出一種虛假的安全感。 也許原本會(huì)待在家里的人會(huì)戴上一個(gè)不合適的口罩

37、跑去坐地鐵。 流感不僅僅是通過空氣傳染。有些人打噴囔時(shí)會(huì)用手遮擋，帶有病毒的手會(huì)接觸到門把手或是地鐵里的扶手。如果你碰到這些東西，然后把帶有流感病毒的手接觸到嘴或者鼻子，你就有可能被傳染。戴口罩時(shí)你很難去擦鼻子，于是臉在口罩下就變得汗津津的，當(dāng)你去擦汗時(shí)，病毒就直接被帶到了鼻子里。這些問題就是口罩帶給他們的使用者的。 人們是否應(yīng)該使用口罩仍然是個(gè)問題。公眾還要耐心地等待科學(xué)家的研究結(jié)果。十四、The Magic Io Personal Digital Pen1Check out the io Personal Digital Pen launched by Logitech：Its a mag

38、ic pen that can store everything you write and transfer it to your computer. And you dont have to lug a hand-held device along with you for it to work.12Logitechs technology works like this：The pen writes normally, using normal ballpoint pen ink2. But while you are writing, a tiny camera inside the

39、pen is also taking 100 snapshots per second of what you are doing3, mapping your writing via a patchwork of minute dots printed on the paper. All this informationthe movement of your pen on the paper, basically is then stored digitally inside the pen, whether you are writing notes or drawing complex

40、 diagrams. You can store up to 40 pages worth of doodles in the pens memory. As far as you are concerned4, you are just using a normal pen.3It is only when you drop the pen into its PC-connected cradle that the fun begins. Special software on your PC will figure out what you have done, and begin to

41、download any documents you have written since the last time it was there. Depending on whether you have ticked certain boxes on the special notepad, it can also tell whether the document is destined to be an e-mail, a “to do” task, or a diagram to be inserted into a word-processing document. Once th

42、e documents are downloaded you can view them, print them out or convert them to other formats.4The io Personal Digital Pen is a neat and simple solution to the problem of storing, sharing and retrieving handwritten notes, as well as for handling diagrams, pictures and other non-text doodling. You do

43、nt have to carry a laptop along with you. All you have to do is just whip out the pen and the special paper and you are off5.5It is a great product because it does not force you to work differentlywalking around with a screen strapped to your arm, or carrying with you extra bits and pieces. The pen

44、is light and works like a normal pen if you need it to, while the special notepads look and feel like notepads. The only strange looks will be from people who are curious why you are writing with a cigar.6The io Personal Digital Pen also has potential elsewhere. FedEx6, for example, is introducing a

45、 version of the pen so that customers can fill out forms by hand instead of punching letters into cumbersome devices. Once that data is digital more or less anything can be done with it transferring it wirelessly to a central computer, for example, or via a hand-phone. Doctors could transmit their p

46、rescriptions direct to pharmacies, reducing fraud; policemen could send their reports back to the station, reducing paperwork.練習(xí)：1.Paragraph 2 F Working Principles of the Io Personal Digital Pen.2.Paragraph 3 BWays to Download the Stored Information3.Paragraph 5 AA Friendly and Convenient Device4.Pa

47、ragraph 6 CExamples of Other Potential Applications of the Io Pen5.There is no need to learn how to use the io Personal Digital Pen because Dit works like an ordinary pen.6.If you want to download what you have done with the magic pen, Eyou simply place the pen into its computer-connected cradle.7.T

48、he magic pen is particularly convenient when you work away from home or office because Ayou dont have to carry your laptop along.8.No matter what you write or draw, Fthe movement of your pen is recorded digitally inside the pen神奇的io私人數(shù)字筆仔細(xì)看看由Logitech公司發(fā)明的io私人數(shù)字筆吧。這是一種神奇的筆?？梢詫⒛銓懙乃袞|西儲(chǔ)存下來并轉(zhuǎn)換到計(jì)算機(jī)上，而你在使

49、用這種數(shù)字筆時(shí)卻不必?cái)y帶手持設(shè)備。Logitech技術(shù)的工作原理如下：這種筆使用一種普通的圓珠筆墨水，和平常一樣寫字。但是當(dāng)你寫字時(shí)，筆內(nèi)的一個(gè)極小的攝像頭也在以每秒鐘100張的速度對(duì)你所寫的內(nèi)容進(jìn)行快速拍攝，通過印在紙上的小點(diǎn)塊拼出你所寫的內(nèi)容。然后，無論你是記筆記還是畫復(fù)雜圖表，所以的信息基本上都是筆在紙上的移動(dòng)都將以數(shù)字形式存儲(chǔ)于筆中。你可在筆的存儲(chǔ)器中存儲(chǔ)多達(dá)40頁的資料。而對(duì)你來說，你只不過是在使用一支普通的筆而已。只有當(dāng)你將筆插入與PC機(jī)連接的筆座中時(shí)，有趣的事才真正開始。你的PC機(jī)的專用軟件會(huì)估算出你所做之事，并下載你最新寫下的所有文件。根據(jù)你是否在專用記事本的一些特定框里打?qū)μ?hào)

50、，這種筆還可以辨別出文檔是電子郵件、“待執(zhí)行”人物還是要插入文字處理文檔的圖表。文檔下載后，你就可以查看、打印或?qū)⑵滢D(zhuǎn)換為其他形式。io私人數(shù)字筆可妥善又簡單地解決手寫筆記的存儲(chǔ)、共享和檢索問題，也可處理圖表、圖片以及其他非文本資料。你不必?cái)y帶電腦，你只需要拿出筆和專門用紙就能開始工作了。這是一種很了不起的產(chǎn)品，因?yàn)槟愕墓ぷ鞑粫?huì)因之產(chǎn)生任何麻煩你不必?cái)y帶顯示屏，也不必?cái)y帶任何附件。它非常輕便，如果你需要的話，也可以當(dāng)普通筆來用，而這種專用記事本看起來摸起來都很像普通記事本。有些人會(huì)很好奇，不明白為什么你在用雪茄寫字，這是唯一看起來令人費(fèi)解的地方。io私人數(shù)字筆在其他方面也很有潛力。例如，聯(lián)邦快

51、遞公司正引進(jìn)一種數(shù)字筆，從而用戶可用手填寫表格，而無需再費(fèi)力勞神地打進(jìn)機(jī)器中。如果數(shù)字為數(shù)字型，幾乎所有事情都可由這種筆來完成例如將數(shù)據(jù)通過無線方式或手機(jī)傳輸?shù)街行挠?jì)算機(jī)上。醫(yī)生可將處方直接轉(zhuǎn)到藥房，減少了欺詐行為的發(fā)生。警察可將報(bào)告發(fā)回警察局，減少了文書工作。+第十五課Maglev Trains1 A few countries are using powerful electromagnets to develop high-speed trains，called maglev trains. Maglev is short for magnetic levitation，which me

52、ans that these trains float over a guideway using the basic principles of magnets to replace the old steel wheel and track trains. 2 If youve ever played with magnet，you know that opposite poles attract and like poles repel each other. This is the basic principle behind electromagnetic propulsion. E

53、lectromagnets are similar to other magnets in they attract metal objects，but the magnetic pull is temporary. You can easily create a small electromagnet yourself by connecting the ends of a copper wire to the positive and negative ends of an AA-cell battery. This creates a small magnetic field. If y

54、ou disconnect either end of the wire from the battery，the magnetic field is taken away. 3 The magnetic field created in this wire-and-battery experiment is the simple idea behind amaglev train rail system. There are three components to this system: A large electrical power source，metal coils lining

55、a guideway or track，and large guidance magnets attached to the underside of the train. 4 The big difference between a maglev train and a conventional train is that maglev trains do not have an engineat least not the kind of engine used to pull typical train cars along steel tracks.The engine for mag

56、lev trains is rather innoticeable. Instead of using fossil fuels，the magnetic field created by the electrified coils in the guideway walls and the track combine to propel the train. 5 The magnetized coil running along the track，called a guideway，repels the large magnets on the train s undercarriage，

57、allowing the train to levitate between 1 to 10 cm above the guideway.Once the train is levitated，power is supplied to the coils within the guideway walls to create a unique system of magnetic fields that pull and push th train along the guideway. The electric current supplied to the coils in the gui

58、deway walls is constantly alternating to change the polarity of the magnetized coi1s. This change in polarity causes the magnetic field in front of the train to pull the vehicle forward，while the magnetic field behind the train adds more forward thrust. 6 Maglev trains float on a cushion of air，elim

59、inating friction. This lack of friction allows these trains to reach unprecedented ground transportation speeds of more than 500 kph，or twice as fast as the fastest conventional train. At 500 kph，you could travel from Paris to Rome in just over two hours. 1. Paragraph 3 A、The Main Components of the

60、Maglev Train System2. Paragraph 4 E、Comparison of Maglev Trains with Traditional Ones3. Paragraph 5 C、The Working Principle of the Maglev Train4. Paragraph 6 B、High-speed Maglev due to Zero Friction5. Several countries in the world are using strong electromagnets A、to develop a maglev train rail sys

61、tem6. You can connect a wire to the positive and negative ends of a battery D、to create a magnetic field7. A unique system of magnetic fields is created by the coils C、to pull and push the train forward8. The frictionless maglev train enables you F、to travel from Paris to Rome in about two hours磁懸浮列

62、車一些國家正在使用強(qiáng)有力的電磁體發(fā)展高速列車，這種列車叫作磁懸浮列車。Maglev是磁懸浮的縮略詞，它意味著這些列車漂浮在導(dǎo)向槽上，導(dǎo)向槽是使用磁鐵的基本原理來替換原來的鋼輪子和鋼軌道的列車。 如果你曾經(jīng)玩過磁鐵，你知道異極相服，同極相斥的道理。這是電磁式推進(jìn)背后的基本原理。電磁體與其他磁鐵在吸引金屬物品方面是一樣的，但是電磁力 是暫時(shí)的。你能通過銅絲連接一節(jié)5號(hào)電池的正負(fù)極很容易地自己創(chuàng)造出一個(gè)小的電磁體。這就創(chuàng)造了一個(gè)小磁場。如果你從電池分開導(dǎo)線的任意一個(gè)末端，磁場就消失。 這個(gè)導(dǎo)線和電池實(shí)驗(yàn)創(chuàng)造的磁場是磁懸浮列車系統(tǒng)背后的簡單想法。這個(gè)系統(tǒng)有三個(gè)成分：一個(gè)大電能來源、金屬卷排列成導(dǎo)向槽或

63、軌道和附著在列車下面的大的導(dǎo)電磁體。 磁懸浮列車和傳統(tǒng)列車之間的一個(gè)很大的大區(qū)別是磁懸浮列車沒有發(fā)動(dòng)機(jī)至少不是沿著軌道拉動(dòng)典型的火車車廂的那種發(fā)動(dòng)機(jī)。磁懸浮列車的發(fā)動(dòng)機(jī)相當(dāng)不顯眼。代替礦物燃料的使用，由嵌入導(dǎo)向壁內(nèi)的電磁線圈產(chǎn)生的磁場加上軌道，一起推動(dòng)火車前進(jìn)。 導(dǎo)向槽是沿著軌道延伸的帶磁性的線圈。它排斥在列車的車盤上的大磁鐵，允許列車在導(dǎo)向槽之上1-10cm之間懸浮。一旦列車被懸浮，就把力量供給在導(dǎo)向槽墻體之內(nèi)的線卷來創(chuàng)造出一個(gè)單獨(dú)的磁場系統(tǒng)，沿著導(dǎo)向槽推拉列車。在導(dǎo)向槽墻體內(nèi)供給線圈的電流不斷交替改變被磁化的線卷的極性。在極性上的變化造成了列車前面的磁場向前拉動(dòng)列車，而在列車后面的磁場增加更多向前推力。 磁懸浮列車漂浮在氣墊上來減少摩擦。這種缺乏摩擦(的狀態(tài))讓這些列車超過500kph的速度，(這個(gè)速度)是地面交通工具史無前例的速度，或者是最快速的傳統(tǒng)列車兩倍的速度。500kph，你可能用剛好超過兩個(gè)小時(shí)的(時(shí)間)從巴黎旅行到羅馬。