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This is Scientific American's 60-Second Science. I'm Karen Hopkin. This will just take a minute.

Are your car bumpers¹ riddled² 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 varnish³ on your floor, even the nylon in your panty hose are all polymers—extremely long chains of molecules⁴ 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 molecular⁵ 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.

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收听单词发音

1 bumpers
（汽车上的）保险杠，缓冲器( bumper的名词复数 )
参考例句：
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。

2 riddled
adj.布满的；充斥的；泛滥的v.解谜，出谜题(riddle的过去分词形式)
参考例句：
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》

3 varnish
n.清漆；v.上清漆；粉饰
参考例句：
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。

4 molecules
分子( molecule的名词复数 )
参考例句：
The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。 Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

5 molecular
adj.分子的；克分子的
参考例句：
The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。 For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。