“Spider silk has been winning this competition for a long time,”Asa Barber,an engineer at the University of Portsmouth,England,who led the study said.“36. ”
A limpet has about a hundred teeth,each about 1 millimeter(0.04 inches) long.37. To find out just how tough limpet teeth are,Barber’s team examined pieces of the limpets’ teeth to test their tensile strength—the resistance of a material to breaking when stretched.The scientists learned that the material that makes up limpet teeth can withstand a pulling force comparable to that of a rope lifting about 1,500 kilograms(3,300 pounds) of sugar.
38. They contain fibers made from a combination of goethite and chitin.39. Chitin,on the other hand,is stretchy(有弹性的).Mix the two together,and you get a material that’s both hard and tough.
In fact,limpet teeth are 10 percent stronger than spider silk.Scientists have had a hard time trying to artificially produce spiders’ sticky web material in a lab,but Barber believes it will be easier to recreate limpet teeth.40. “I think this is going to be a much greater opportunity to manufacture materials that have high strength,”he says.
A.What makes limpet teeth so strong?
B.Though hard,goethite breaks easily.
C.A limpet has a tongue covered with tiny teeth.
D.It uses them to get its preferred meal off rocks.
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