An Application Of Nanotechnology托福聽力原文翻譯及問題答案

An Application Of Nanotechnology托福聽力原文翻譯及問題答案

一、An Application Of Nanotechnology托福聽力原文：

NARRATOR:Listen to part of a lecture in a materials science class.

MALE PROFESSOR OK.Last time we finished going over some of the fundamental concepts of nanotechnology—the multidisciplinary science of manipulating—or controlling—extremely small units of matter,on the scale of molecules or even atoms.

So,I want to talk about how nanotechnology is being used today,and,just to give you an idea,we'll look at one particular application.

A team of materials scientists in Massachusetts has been working on a new,ultrathin coating,a nanocoating that might be applied to objects like bathroom mirrors,car windows,and eyeglasses to prevent fogging.And the coating has the potential to be a permanent solution,unlike the kinds of anti-fogging,spray-on liquids that are on the market today...

Now,fogging often occurs when a cold surface comes into contact with warm,moist air,such as when a glass shower door or mirror fogs up during a warm shower.…

Now,what's actually happening is,uh,what the fog is,is thousands of tiny spherical water droplets condensing on the surface of the glass.Light hits the water droplets and is scattered in random directions,causing the fogging effect.

Now,the kind of spray-on treatments I mentioned,well,they wear off.What happens is they cause the tiny water droplets to flatten when they condense on the surface of the shower door,or bathroom mirror,or whatever object it is that it's been applied to.

Because the droplets are flattened,when light hits them,the light doesn't scatter.But as I said,those kinds of treatments don't last very long.

The new coating has two important components.One:negatively charged silica nanoparticles—these are basically tiny particles of glass.And two:a positively charged polymer—which,you already know,a polymer is a chemical compound.These're layered over each other…the polymer,then the silica nanoparticles,the polymer,then the silica nanoparticles,you see.They're layered in such a way that the silica nanoparticles don't pack together tightly.In other words,the structure has pores,or holes,little tiny pockets,throughout it.

The coating prevents fog from developing because it loves water.It attracts the water droplets—sucking them into the tiny pores.And that alters the shape of the droplets;the droplets are forced to flatten and to join together into a single sheet of water,rather than remaining as single droplets—each of which is a sphere that scatters light in different directions.

OK,so instead of being scattered,the light passes through the thin sheet of water.So there's no fogging effect.

The ultrathin coating can be made more durable by heating it—and of course the object it's applied to—to an extremely hot temperature—500 degrees Celsius.What that does is burn the polymer away and fuse the silica nanoparticles together—while maintaining the structure of pores.

But that's possible only on materials that can withstand high heat.Glass,yes.Plastics,no.But they're working on solving that problem;trying to come up with a way to coat plastics and other materials durably and effectively.

Interestingly,it was a plant—the lotus plant—that inspired this work,I guess you could say inspired it in an indirect sort of way.The leaves of this plant are what we call“superhydrophobic.”Lotus leaves,being superhydrophobic,don’t attract water—they repel it—in a big way.When raindrops fall on lotus leaves,they remain spherical.They roll right off.

So for a long time the Massachusetts scientists tried to create a coating that acted like these lotus leaves—a coating that was superhydrophobic.But then they began to think about the opposite extreme.Uh,could they accomplish their goal by making a coating that,instead of repelling water,actually attracted water?

Well,they seem to have gotten quite far with this approach.It’s really strong work with a range of interesting consumer applications.It's not costly to manufacture the coating.Some car makers are interested in applying it to their windshields.Looks like we'll probably see it on the markets in everyday products in the next few years.

二、An Application Of Nanotechnology托福聽力中文翻譯：

旁白：在材料科學課上聽講座的一部分。

男教授好的。上次我們講完了納米技術的一些基本概念，這是一門多學科的科學，在分子甚至原子的尺度上操縱或控制極小的物質(zhì)單位。

所以，我想談談納米技術今天是如何被使用的，為了給你一個想法，我們將看看一個特定的應用。

馬薩諸塞州的一個材料科學家團隊正在研究一種新型超薄涂層，一種納米涂層，可用于浴室鏡子、車窗和眼鏡等物體，以防起霧。這種涂層有可能成為一種永久性的解決方案，不像今天市場上的那種防霧、噴霧液體。。。

現(xiàn)在，當寒冷的表面接觸到溫暖潮濕的空氣時，通常會出現(xiàn)霧化，例如當玻璃淋浴門或鏡子在溫暖的淋浴過程中起霧時?！?/p>

現(xiàn)在，實際發(fā)生的是，呃，霧是什么，是數(shù)千個微小的球形水滴凝結(jié)在玻璃表面。光線擊中水滴，并向隨機方向散射，從而產(chǎn)生霧化效果。

現(xiàn)在，我提到的那種噴霧療法，嗯，它們會逐漸消失。發(fā)生的情況是，當微小水滴凝結(jié)在淋浴門、浴室鏡子或任何物體表面時，它們會導致水滴變平。

因為水滴是扁平的，當光線照射到它們時，光線不會散射。但正如我所說，這種治療不會持續(xù)很長時間。

新涂層有兩個重要組成部分。第一：帶負電的二氧化硅納米顆粒這些基本上是玻璃的微小顆粒。第二：帶正電的聚合物，你已經(jīng)知道，聚合物是一種化合物。這些是相互層疊的……聚合物，然后是二氧化硅納米顆粒，聚合物，然后是二氧化硅納米顆粒，你看。它們的分層方式使得二氧化硅納米顆粒不會緊密地聚集在一起。換言之，整個結(jié)構(gòu)都有孔隙，或孔洞，小的小口袋。

這種涂層可以防止霧的形成，因為它喜歡水。它會吸引水滴，將其吸入微小的孔隙中。這改變了水滴的形狀；這些水滴被迫變平并結(jié)合在一起形成一片水，而不是保持為單個水滴，每個水滴都是一個向不同方向散射光的球體。

好的，所以光不是散射的，而是通過薄薄的一層水。所以沒有霧化效應。

通過加熱超薄涂層，可以使其更加耐用，當然，也可以將其涂敷的物體加熱到極熱的溫度——500攝氏度。這樣做的目的是燒掉聚合物并將二氧化硅納米顆粒融合在一起，同時保持孔隙結(jié)構(gòu)。

但這只有在耐高溫的材料上才可能實現(xiàn)。玻璃，是的。塑料，沒有。但他們正在努力解決這個問題；試圖找到一種持久有效地涂覆塑料和其他材料的方法。

有趣的是，正是一種植物——蓮花——啟發(fā)了這部作品，我想你可以說是間接地啟發(fā)了它。這種植物的葉子被我們稱為“超疏水”荷葉是超疏水的，它不吸水，但對水有很大的排斥作用。當雨滴落在荷葉上時，它們保持球形。他們馬上滾下來。

因此，在很長一段時間里，馬薩諸塞州的科學家們試圖創(chuàng)造一種像這些荷葉一樣的涂層——一種超疏水涂層。但后來他們開始考慮另一個極端。呃，他們能通過制造一種涂層來實現(xiàn)他們的目標嗎？這種涂層不是防水，而是吸水？

嗯，他們似乎已經(jīng)用這種方法走得很遠了。它與一系列有趣的消費者應用程序配合使用，效果非常好。制造涂層并不昂貴。一些汽車制造商有興趣將其應用于擋風玻璃?？磥碓谖磥韼啄辏覀兛赡軙谌粘Ｓ闷肥袌錾峡吹剿?。

三、An Application Of Nanotechnology托福聽力問題：

Q1:1.What is the main purpose of the lecture?

A.To provide an example of a practical use of nanotechnology.

B.To show the origins of the field of nanotechnology.

C.To give a brief outline of the main concepts of nanotechnology.

D.To explain the growing interest in nanotechnology research.

Q2:2.How does the professor organize the information he presents to the class?

A.He describes the inspiration behind the nanocoating,then how the coating works.

B.He describes how the nanocoating is currently marketed,then the inspiration behind it.

C.He explains how fogging occurs,then the basic concepts of nanotechnology.

D.He explains how fogging occurs,then how the nanocoating prevents it.

Q3:3.According to the professor,how does the new nanocoating work?

A.By forcing light to bounce off a glass-coated polymer.

B.By forcing water droplets to roll off an ultrathin surface.

C.By causing water droplets to merge into a single sheet of water.

D.By causing light to scatter randomly in many directions.

Q4:4.According to the information in the lecture,why does the new nanocoating not last as long on plastic as it does on glass?

A.Plastic cannot withstand extremely high temperatures.

B.The internal structure of plastic repels a positively charged polymer.

C.The coating solution scatters when it comes into contact with plastic.

D.Plastic surfaces scratch more easily than glass surfaces do.

Q5:5.What inspired the team of scientists in developing the new coating?

A.A problem the team frequently encountered in everyday life.

B.The ineffectiveness of spray solutions in flattening water droplets.

C.The leaves of a plant that the team had been investigating.

D.Interactions observed between silica nanoparticles and polymers.

Q6:6.What is the professor's opinion about the approach inventors took to the development of the new nanocoating?

A.He thinks other inventors should use a similar approach.

B.He is impressed by the flexibility of their approach.

C.He is surprised the research process took so long.

D.He thinks they should have spent more time testing a superhydrophobic coating.

四、An Application Of Nanotechnology托福聽力答案：

A1:正確答案：A

A2:正確答案：D

A3:正確答案：C

A4:正確答案：A

A5:正確答案：C

A6:正確答案：B

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