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科学美国人60秒:潜水用保暖材料类似海狸毛皮-托福听力下载

2016-12-12 15:20:46来源:科学美国人60秒

  科学美国人60秒中文翻译:

  This is Scientific American — 60-Second Science. I'm Cynthia Graber. 这里是科学美国人——60秒科学。我是辛西娅·格雷伯。

  Whales, seals and walruses stay warm in chilly water because they have a thick layer of blubber. 鲸鱼,海豹和海象可以在寒冷的水中维持体温,因为它们有很厚的脂肪层。

  We humans rely on something like blubber—neoprene rubber wet suits—to spend time in cold water. 我们人类则可以依靠类似于脂肪的氯丁橡胶潜水服在冰冷的水中活动。

  But the thick versions for really icy water are heavy and ungainly. 可是在冰水中穿着厚厚的潜水服又沉重又笨拙。

  So rather than taking after big marine mammals, 那除了效仿大型海洋哺乳动物,

  what if we could learn from the littler ones, like beavers and otters? 向河狸和水獭等小型海洋哺乳动物学习是否也可以呢?

  "These animals are quite small and they can't carry around a thick layer of blubber. “这些动物都很小,它们没有厚厚的脂肪层。

  So instead they have fur that is evolved to trap air, 所以它们进化出了可以存留空气的皮毛,

  and this air provides a layer of insulation for them in water." 存留的空气为它们在水中活动时提供了隔热层。”

  Alice Nasto is a graduate student in mechanical engineering at MIT. 爱丽丝·纳斯托是麻省理工学院机械工程专业的研究生。

  Scientists have known about this air-trapping insulation mechanism for a long time, 科学家们很早就发现了这种存留空气形成的隔热机制,

  but they had not teased out the details of how it works. 但是他们并没有测试出这种机制的具体原理。

  So Nasto and her colleagues took on the challenge. 所以纳斯托和她的同事们接受了这项挑战。

  "We're creating these furry samples from these rubbery materials by laser cutting molds and casting these hairy surfaces. “我们用激光切割模具将这些橡胶材料制成了毛皮样本,然后铸造出这些毛茸茸的表面。

  And through our approach we can precisely control the spacing of the hairs and the length of the hairs." 通过这种方法,我们可以精确地控制毛发间的距离以及毛发的长度。”

  The researchers then created a system 然后,研究人员创建了一个系统,

  to gather data when their pelts entered and moved through a liquid— 在毛皮进入液体并在液体里移动时收集相关数据,

  in this case not water, but silicone oil, which makes it easier to see air bubbles. 这种液体并不是水,而是硅油,用硅油更易在试验过程中看到气泡。

  The key is to keep the pelt's air layer intact. 关键是要保持毛皮空气层的完整性。

  "So when they're crossing the air water interface, initially their hairy texture is full of air. “当它们穿过气液界面时,一开始毛发材质充满了空气。

  And then you go into water. 然后,把它们投入液体中。

  How much of the air comes down with you as you're moving in through the interface. 当你移动它穿过气液界面时,你可以带动多少空气?

  So that's what this model will tell you." 这就是我们设计的模型会告诉大家的事情。”

  They found that the denser the hairs, the more the air gets trapped. 他们发现,毛发的密度越大,存留的空气就越多。

  Which should keep the animal—or potentially the human in a future furry wet suit—warm. 这就可以使动物保持温暖,或许未来也可以使穿着毛皮潜水服的人类保暖。

  The research is in the journal Physical Review Fluids. 该研究结果发表在《流体物理评论》期刊上。

  "What we would like to work on moving forward is understanding how, after you dive into the water, “我们接下来想继续研究的是,在你跳入水中后,

  how do you maintain this air layer trapped in your fur. 如何让这个空气隔热层一直存留在毛皮里。

  And there's lots of interesting properties of the fur in nature that we haven't yet looked at in our model 在我们设计的这个模型中,这种毛皮的许多有趣特点我们还没有研究,

  that could help explain how this mechanism might work." 进一步了解它们也许能够解释这种机制的原理。”

  So for now, cold-water divers and surfers will still emulate seals or sea lions. 现在,冷水潜水员或冲浪者仍会继续模仿海豹和海狮。

  But the day may come when they'll more closely resemble otters or beavers. 而他们模仿水獭或者海狸的那一天终将会到来的。

  Or even a Wookiee on a boogie board. 也许你甚至会看到玩冲浪板的“伍基人”。

  Thanks for listening for Scientific American — 60-Second Science Science. I'm Cynthia Graber. 谢谢大家收听科学美国人——60秒科学。我是辛西娅·格雷伯。

  以上就是新东方在线托福网为你带来的科学美国人60秒中英文文本翻译音频下载等资料,更多精彩敬请关注新东方在线托福网。

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