SSS 2012-02-01
时间:2019-01-08 作者:英语课 分类:Scientific American(二)月
It's tough to be a machine in the desert. Particles of dirty sands walk their way in to moving parts where they break turbine's motors pipes on other equipment.To avoid the costly 1 warranty 2, researches are taking lessons from a desert native, the yellow fat scorpion 3. Scorpion protect their bodies with exo-skeletons in order to minimize rubbing from air-born sand. The pattern on this armor modify the way that air flow over the scorpion's back. The researches scan the scorpion's body and use the natural pattern in inspiration for a variety of surfaces. With the computer model to simulate the airflow over the digital surfaces and wind tunnel for testing the physical samples, the researches are trying to develop the best texture 4 for avoiding sand damage. Their work is in the Material Science Journal Annual. Although all texture surfaces feel better than smooth ones, one type of pattern resist the erosion best. Small dews cut the 30 degree angle to direction of the airflow. The machine whose surfaces are engraved 5 with this texture should fight off the erosion like the scorpion do, where smoother equipment comes to the sting of sand.
This post was generated by put listening repetition system, Check the original dictation thread!
- It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
- This dictionary is very useful,only it is a bit costly.这本词典很有用,左不过贵了些。
- This warranty is good for one year after the date of the purchase of the product.本保证书自购置此产品之日起有效期为一年。
- As your guarantor,we have signed a warranty to the bank.作为你们的担保人,我们已经向银行开出了担保书。
- The scorpion has a sting that can be deadly.蝎子有可以致命的螫针。
- The scorpion has a sting that can be deadly.蝎子有可以致命的螫针。
- We could feel the smooth texture of silk.我们能感觉出丝绸的光滑质地。
- Her skin has a fine texture.她的皮肤细腻。