英語聽力文摘497 像霧一樣的固體物質(zhì)
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】
aerogel：氣凝膠，又稱為干凝膠。是一種固體物質(zhì)形態(tài)，世界上密度最小的固體。當(dāng)凝膠脫去大部分溶劑，使凝膠中液體含量比固體含量少得多，或凝膠的空間網(wǎng)狀結(jié)構(gòu)中充滿的介質(zhì)是氣體，外表呈固體狀，這即為干凝膠，也稱為氣凝膠。
slam into：猛烈撞擊
space probe：航空探測器
