SSS 2011-04-20
时间：2018-12-24 作者：英语课 分类：Scientific American(四)月
This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute.
Are your car bumpers 1 riddled 2 with scars from encounters with tight parking spaces? Did the furniture movers scratch your floor? Wouldn't it be great if those marks could just disappear? Well, thanks to the magic of chemistry, maybe such nicks will soon be nipped. Because scientists have produced a material that can actually heal itself, work published in the journal Nature.
The paint on your car, the varnish 3 on your floor, even the nylon in your panty hose are all polymers—extremely long chains of molecules 4 held together by strong chemical bonds. But this new material isn't like any old polymer. It's a supramolecular polymer, made of smaller molecules held together by weak interactions with metals, which act like a kind of molecular 5 Velcro.
When this polymeric material is torn, exposing it to an intense beam of UV radiation breaks the weak bonds in and around the tear. That disruption allows the material to flow like a liquid, which then heals the wound. When the light is switched off the polymer resolidifies, leaving the surface as good as new. Which would be good news for your bumpers. And for your teenager, who won't have to explain the ding on your car.
Thanks for the minute. For Scientific American's 60-Second Science, I'm Karen Hopkin.
- Our bumpers just grazed (ie touched each other) as we passed. 我们错车时保险互相蹭了一下。
- Car stickers can be attached to the bumpers or windows. 汽车贴纸可以贴在防撞杆上或车窗上。
- The beams are riddled with woodworm. 这些木梁被蛀虫蛀得都是洞。
- The bodies of the hostages were found riddled with bullets. 在人质的尸体上发现了很多弹孔。 来自《简明英汉词典》
- He tried to varnish over the facts,but it was useless.他想粉饰事实，但那是徒劳的。
- He applied varnish to the table.他给那张桌子涂上清漆。