时间:2019-01-08 作者:英语课 分类:Scientific American(三)月


英语课

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


If you get a scratch, your skin can heal itself. But if your car gets scratched, it stays scratched. Scientists at the University of Southern Mississippi think they may have solved that problem. They’ve developed a new material that can self-heal scratches when exposed to sunlight. They published this research in the March 13th edition of the journal Science.


The new technology first takes polyurethane—the coating on many cars. Then researchers added chitosan—that’s a key polymer in crab 1 and shrimp 2 shells. The final bit thrown into the mix are minute amounts of oxetane rings, with three atoms of carbon and one of oxygen.


The researchers are trying to mimic 3 natural processes. Here’s how it works. When there’s a scratch, damaging the molecule 4, the oxetane ring opens. It has two reactive ends. In sunlight, chitosan breaks into two chains and generates free radicals 5. Then those chitosan chains link up with the reactive ends of the oxetane, filling in the scratch.


Researchers say this technique is much simpler and more cost-efficient than other attempts at self-healing. So maybe in the future, when your car gets scraped, it’ll be all healed up before you have to spend any of your hard earned scratch.


 


Thanks for the minute for Scientific American's 60-Second Science. I'm Cynthia Graber.


 



n.螃蟹,偏航,脾气乖戾的人,酸苹果;vi.捕蟹,偏航,发牢骚;vt.使偏航,发脾气
  • I can't remember when I last had crab.我不记得上次吃蟹是什么时候了。
  • The skin on my face felt as hard as a crab's back.我脸上的皮仿佛僵硬了,就象螃蟹的壳似的。
n.虾,小虾;矮小的人
  • When the shrimp farm is built it will block the stream.一旦养虾场建起来,将会截断这条河流。
  • When it comes to seafood,I like shrimp the best.说到海鲜,我最喜欢虾。
v.模仿,戏弄;n.模仿他人言行的人
  • A parrot can mimic a person's voice.鹦鹉能学人的声音。
  • He used to mimic speech peculiarities of another.他过去总是模仿别人讲话的特点。
n.分子,克分子
  • A molecule of water is made up of two atoms of hygrogen and one atom of oxygen.一个水分子是由P妈̬f婘̬ 妈̬成的。
  • This gives us the structural formula of the molecule.这种方式给出了分子的结构式。
n.激进分子( radical的名词复数 );根基;基本原理;[数学]根数
  • Some militant leaders want to merge with white radicals. 一些好斗的领导人要和白人中的激进派联合。 来自《简明英汉词典》
  • The worry is that the radicals will grow more intransigent. 现在人们担忧激进分子会变得更加不妥协。 来自辞典例句
标签: SSS shrimp
学英语单词
abrasion wear test machine
abreed
abstracto
Aguamansa
aldanas
allowable stress intensity
alumina porcelain crown
AMP(amplifier)
anharmonicity
atrial confluent wave
Bawlf
bearing center line
berat (berati)
biofunctional
biotite gneiss
blacks up
breeding reactor
Ceractinomorpha
counterimpulse
cpj
cusping
Cynophenphos
damans
decentralized control system
decoder truncated
dispatch meeting
durdens
electric driving boat
error calls
external ordering
fabricated food
floor joist
forward spining
fouling marker
genus Pipilo
grease sb.'s fist
ground equalizer inductors
guest of honor
gutter ball
halwas
hang in the balance
harlequin
Helmholtzian
independent instigator
International New Photos
kubin
lift motor
Liparis regnieri
Lobanovo
margarodite
measure punishment
medium-incomes
Mike Hammer
Morse telegraphy
NAS
nemeous
neottia nankomontana
NewLink
non-public
nonidealized
numerical abnormalities of chromosomes
odd integer
odontophylaxis
oshiro
paisant
pedestrian traffics
Picotte, Susan La Flesche
pig trough
piloted simulation
pine ferns
QDNO
quasi-arbitrators
rear-wheel ballast
regeneration cycle operation
relay tree
repertory company
reverse commuters
rezzed
SDF (standard distribution format)
self supporting cable
shore communications
Sol I
spherical helix
St-Cyrille
staig
Staines, Pen.
stop a shell
sulcus tympanicus
sutlers
TAHBSO
Tasselot, Mt.
temeritous
transient cavitation
transverse fibers of pons
unexhibitable
Unlisted Securities Market
unocular
unrefuelled range
upland peat
virtual image
well-word
zophar