英語聽力文摘497 像霧一樣的固體物質(zhì)

所屬教程:英語聽力文摘

瀏覽:

手機版

掃描二維碼方便學(xué)習(xí)和分享

00:00

MP3下載文本下載

Frozen Smoke

固體煙

Male: What's as light as smoke but strong as a brick?

Female: I'm gonna take a while guess and say... aerogel?

Male: Sorry,yaoyao,the answer is... Wait a second! Did you say aerogel? How did you know?

F:Yeap! Did you know that aerogel is the lightest solid on earth?

M: I was going to tell you that.

F: Another cool thing is that it starts out as a kind of chemical Jello. Then the gel is dried in a powerful pressure cooker and emerges as a very lightweight, dry, sponge- like material that looks like frozen smoke.

M: OK! Did you know that aerogel is ninety-nine-point-eight percent air?

F: Sure.That was in your notes.And it’s incredibly light–one thousand times less dense than glass. But it's also really strong and an excellent insulator.

M: Is there anything you don't know about aerogel? For instance,scientists are using it to try to capture dust particles from the tail of a comet. When the particlesslam into an aerogelpanel aboard a space probe, they'll bury themselves inside and leave visible trails. Since aerogel is mostly air, it won't damage the particles.

F: Actually, I know that too.

男：什么東西既可以跟煙一樣輕，又可以跟磚塊一樣重?

女：讓我想會兒... 氣凝膠?

男：瑤瑤，不好意思，答案是... 等等!你說的是氣凝膠嗎?你是怎么知道的?

女：是的!你知道氣凝膠是地球上最輕的固體嗎?

男：我剛剛正要告訴你呢!

女：了不起的是，氣凝膠開始是作為一種化學(xué)凝膠物的。然后膠體在壓力很強的鍋里變干，成為了一種重量很輕、很干燥、類似海綿狀，看起來像固體煙霧的物體。

男：是的!那你知道氣凝膠中99.8%都是空氣嗎?

女：知道啊!你的筆記中有的!氣凝膠相當(dāng)?shù)妮p，輕到密度只有玻璃的千分之一。但它也很結(jié)實，是幾號的絕緣體。

男：關(guān)于氣凝膠，你還有什么不知道的嗎?比如說，科學(xué)家正在試圖用它捕捉彗星經(jīng)過的微塵。當(dāng)(微塵)顆粒猛烈撞擊到航空探測器上的氣凝膠板時，它們將會自然，從而留下可見的痕跡。因為氣凝膠差不多等同于空氣，并不會破壞(微塵)顆粒。

女：其實這個我也知道!

【W(wǎng)ords & Expressions】