SSS 2008-07-08
时间:2019-01-08 作者:英语课 分类:Scientific American(七)月
This is Scientific American's 60-Second Science, I am Cynthia Graber. This'll just take a minute.
Whales and dolphins were molded by evolution to glide 1 through water. We’ve been trying to create streamlined designs ourselves for structures such as wind turbine blades. Now researchers are examining the flippers, fins 3 and tails of our water-dwelling cousins to learn how to improve engineering designs. Doctor Frank Fish—yes, that’s really his name, from West Chester University in Pennsylvania presented this research July 8 at the Society for Experimental Biology’s annual meeting in Marseille.Here’s one example of the way Doctor Fish’s research is being applied 4. Whale flippers have a bumpy 5 edge. This makes little sense to engineers. They’ve designed structures like wings and blades that ensure a steady air flow. But it turns out the unsteady flow over this more complex shape increases lift and reduces drag much better than any previous manmade design. It has to do with something called vortices. These are small tornado-shaped water formations in an animal’s wake. The bumps on a whale’s flipper 2 help form vortices that generate more lift, more smoothly 6. Engineers are using this insight to design an entirely 7 new wind turbine blade so that we can generate power from wind as efficiently 8 as whales and dolphins fly through the water.
Thanks for the minute for Scientific American's 60-Second Science, and I'm Cynthia Graber.
- We stood in silence watching the snake glide effortlessly.我们噤若寒蝉地站着,眼看那条蛇逍遥自在地游来游去。
- So graceful was the ballerina that she just seemed to glide.那芭蕾舞女演员翩跹起舞,宛如滑翔。
- The seal's flipper is homologous with the human arm. 海豹的鳍肢与人类的手臂同源。
- It's almost like a flipper action as she kicks down. 她向下踢腿时有鱼鳍的效果。
- The level of TNF-α positively correlated with BMI,FPG,HbA1C,TG,FINS and IRI,but not with SBP and DBP. TNF-α水平与BMI、FPG、HbA1C、TG、FINS和IRI呈显著正相关,与SBP、DBP无相关。 来自互联网
- Fins are a feature specific to fish. 鱼鳍是鱼类特有的特征。 来自辞典例句
- She plans to take a course in applied linguistics.她打算学习应用语言学课程。
- This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。
- I think we've a bumpy road ahead of us.我觉得我们将要面临一段困难时期。
- The wide paved road degenerated into a narrow bumpy track.铺好的宽阔道路渐渐变窄,成了一条崎岖不平的小径。
- The workmen are very cooperative,so the work goes on smoothly.工人们十分合作,所以工作进展顺利。
- Just change one or two words and the sentence will read smoothly.这句话只要动一两个字就顺了。
- The fire was entirely caused by their neglect of duty. 那场火灾完全是由于他们失职而引起的。
- His life was entirely given up to the educational work. 他的一生统统献给了教育工作。
- The worker oils the machine to operate it more efficiently.工人给机器上油以使机器运转更有效。
- Local authorities have to learn to allocate resources efficiently.地方政府必须学会有效地分配资源。