1.Whales,seals and walruses stay warm in cold water because they have a thick layer of blubber.We humans rely on something like blubber-neoprene rubber wet suits-to spend time in cold water.But the thick versions for really icy water are heavy and clumsy.So rather than taking after big marine mammals,what if we could learn from the littler ones,like beavers and otters?
"These animals are quite small and they can't carry around a thick layer of blubber.So instead they have fur that is evolved to trap air,and this air provides a layer of insulation for them in water."
Alice Nasto is a graduate student in mechanical engineering at MIT.Scientists have known about this air-trapping insulation mechanism for a long time,but they had not teased out the details of how it works.So Nasto and her colleagues took on the challenge.
"We're creating these furry samples from these rubbery materials by laser cutting molds and casting these hairy surfaces.And through our approach we can precisely control the spacing of the hairs and the length of the hairs."
The researchers then created a system to gather data when their pelts (毛皮) entered and moved through a liquid-in this case not water,but silicone oil,which makes it easier to see air bubbles.The key is to keep the pelt's air layer intact (完好的).
"So when they're crossing the air water interface,initially their hairy texture is full of air.And then you go into water.How much of the air comes down with you as you're moving in through the interface.So that's what this model will tell you."
They found that the denser the hairs,the more the air gets trapped,which should keep the animal-or potentially the human in a future furry wet suit-warm.The research is in the journal Physical Review Fluids.
"What we would like to work on moving forward is understanding,after you dive into the water,how do you maintain this air layer trapped in your fur.And there's lots of interesting properties of the fur in nature that we haven't yet looked at in our model that could help explain how this mechanism might work."
So for now,cold-water divers and surfers will still emulate seals or sea lions.But the day may come when they'll more closely resemble otters or beavers.
62.What can make littler mammals keep warm in cold water?C
A.An air-trapping insulation mechanism.
B.A thick layer of blubber.
C.A fur that is evolved to trap air.
D.A neoprene rubber wet suit.
63.Nasto and her colleagues have revealedA.
A.the denser the hairs,the more the air can be carried with.
B.the way this air-trapping insulation mechanism works.
C.how the air layer trapped in the fur is maintained in water.
D.the existence of the air-trapping insulation mechanism.
64.The passage is most probably taken fromD.
A.a newspaper
B.a travel book
C.a medical report
D.a science magazine
65.What is the best title for the passage?A
A.A Fantastic Layer of Fur
B.An Important Research
C.A Wonderful Mechanism
D.A Graduate's Challenge.
分析 主要讲述了小型动物在冬天的时候依靠他们薄薄的皮毛,进化成空气滞留的隔热机理的事,说明皮毛层也是很神奇的.
解答 62.C 细节题.根据文章内容,So instead they have fur that is evolved to trap air,and this air provides a layer of insulation for them in water…Scientists have known about this air-trapping insulation mechanism for a long time,but they had not teased out the details of how it works.没有又厚又浓的皮毛保暖,像海狸这样的小动物会有进化成隔绝空气,尤其冷空气的皮,而这种空气滞留的隔热机理也正是科学家们所研究的对象,结合选项,故选C
63.A 细节题.根据文章内容,They found that the denser the hairs,the more the air gets trapped,…由此可知,Nasto和他的同事们发现毛发越浓密,更多的空气会进入,结合选项,故选A
64.D 文章来源题.本文主要研究的是小型动物是如何在冬日保暖,还涉及到科学家对他们的研究等,应该出现在科学杂志上.结合选项,故选D
65.A 主旨题.根据文章内容.主要讲述了小型动物在冬天的时候依靠他们薄薄的皮毛,进化成空气滞留的隔热机理的事,说明皮毛层也是很神奇的.结合选项,故选A
点评 本文是一个科教类阅读,题目涉及多道细节理解题,做题时结合原文和题目有针对性的找出相关语句进行仔细分析,结合选项选出正确答案.推理判断题也是要在抓住关键句子的基础上合理的分析才能得出正确答案,切忌胡乱猜测,一定要做到有理有据.