An Application Of Nanotechnology托福听力原文翻译及问题答案

An Application Of Nanotechnology托福听力原文翻译及问题答案

一、An Application Of Nanotechnology托福听力原文：

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托福听力中文翻译：

旁白：在材料科学课上听讲座的一部分。

男教授好的。上次我们讲完了纳米技术的一些基本概念，这是一门多学科的科学，在分子甚至原子的尺度上操纵或控制极小的物质单位。

所以，我想谈谈纳米技术今天是如何被使用的，为了给你一个想法，我们将看看一个特定的应用。

马萨诸塞州的一个材料科学家团队正在研究一种新型超薄涂层，一种纳米涂层，可用于浴室镜子、车窗和眼镜等物体，以防起雾。这种涂层有可能成为一种永久性的解决方案，不像今天市场上的那种防雾、喷雾液体。。。

现在，当寒冷的表面接触到温暖潮湿的空气时，通常会出现雾化，例如当玻璃淋浴门或镜子在温暖的淋浴过程中起雾时。…

现在，实际发生的是，呃，雾是什么，是数千个微小的球形水滴凝结在玻璃表面。光线击中水滴，并向随机方向散射，从而产生雾化效果。

现在，我提到的那种喷雾疗法，嗯，它们会逐渐消失。发生的情况是，当微小水滴凝结在淋浴门、浴室镜子或任何物体表面时，它们会导致水滴变平。

因为水滴是扁平的，当光线照射到它们时，光线不会散射。但正如我所说，这种治疗不会持续很长时间。

新涂层有两个重要组成部分。第一：带负电的二氧化硅纳米颗粒这些基本上是玻璃的微小颗粒。第二：带正电的聚合物，你已经知道，聚合物是一种化合物。这些是相互层叠的……聚合物，然后是二氧化硅纳米颗粒，聚合物，然后是二氧化硅纳米颗粒，你看。它们的分层方式使得二氧化硅纳米颗粒不会紧密地聚集在一起。换言之，整个结构都有孔隙，或孔洞，小的小口袋。

这种涂层可以防止雾的形成，因为它喜欢水。它会吸引水滴，将其吸入微小的孔隙中。这改变了水滴的形状；这些水滴被迫变平并结合在一起形成一片水，而不是保持为单个水滴，每个水滴都是一个向不同方向散射光的球体。

好的，所以光不是散射的，而是通过薄薄的一层水。所以没有雾化效应。

通过加热超薄涂层，可以使其更加耐用，当然，也可以将其涂敷的物体加热到极热的温度——500摄氏度。这样做的目的是烧掉聚合物并将二氧化硅纳米颗粒融合在一起，同时保持孔隙结构。

但这只有在耐高温的材料上才可能实现。玻璃，是的。塑料，没有。但他们正在努力解决这个问题；试图找到一种持久有效地涂覆塑料和其他材料的方法。

有趣的是，正是一种植物——莲花——启发了这部作品，我想你可以说是间接地启发了它。这种植物的叶子被我们称为“超疏水”荷叶是超疏水的，它不吸水，但对水有很大的排斥作用。当雨滴落在荷叶上时，它们保持球形。他们马上滚下来。

因此，在很长一段时间里，马萨诸塞州的科学家们试图创造一种像这些荷叶一样的涂层——一种超疏水涂层。但后来他们开始考虑另一个极端。呃，他们能通过制造一种涂层来实现他们的目标吗？这种涂层不是防水，而是吸水？

嗯，他们似乎已经用这种方法走得很远了。它与一系列有趣的消费者应用程序配合使用，效果非常好。制造涂层并不昂贵。一些汽车制造商有兴趣将其应用于挡风玻璃。看来在未来几年，我们可能会在日常用品市场上看到它。

三、An Application Of Nanotechnology托福听力问题：

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托福听力答案：

A1:正确答案：A

A2:正确答案：D

A3:正确答案：C

A4:正确答案：A

A5:正确答案：C

A6:正确答案：B