2020年经济学人 脑震荡(1)

Anyone who has experimented as a child with maize¹ starch² and water knows about shear-thickening.

任何在童年做过玉米淀粉加水实验的人都知道剪切增稠。

A mixture of these substances is easy to stir slowly, but solidifies³ when you speed the stirring up, only to liquefy again when you stop.

慢慢搅拌这些物质的混合物很容易，但当你加速搅拌时，混合物会凝固，只有当你停止搅拌时，它才会再次液化。

It's fun. But it may also be important. For years, people have been trying to apply the principle to armour⁴. Now, it seems, one group has succeeded.

很有趣，但也很重要。多年来，人们一直尝试将这个原理应用于装甲部队。现在有一组团队似乎已经成功了。

The result will not stop a speeding bullet. But, incorporated into a helmet, it might save the wearer from concussion⁵.

结果是，它无法阻止一颗飞速的子弹，但如果与头盔结合在一起，或许可以让佩戴者免于脑震荡。

Construction workers, soldiers and sportsmen and women all wear safety helmets

建筑工人、士兵、运动员都要戴安全帽

that contain impact-absorbing suspension systems based on foam⁶ pads or webbing straps⁷.

其中含有基于泡沫垫或织带的可吸收冲击的悬架装置。

Eric Wetzel of the United States Army Research Laboratory and his colleagues propose replacing these

美国陆军研究所的Eric Wetzel和他的同事提议将这些替换成

with fabric⁸ tubes containing a shear-thickening material that the lab has developed.

由实验室研发的一种含有剪切增稠材料的织物圆筒。

These tubes, which behave like viscous⁹, speed-sensitive bungee cords, are known as rate-activated tethers, or RATS.

这些类似粘性、速度敏感型弹力绳的织物圆筒被称为速率激活拴绳或RATS。

A standard bungee cord's useful property is its elasticity¹¹. This first stores energy as the jumper falls and then releases it as he bounces back up again.

标准弹力绳的有用特性是它的弹性。现在蹦极者跳下去的时候储存能量，然后在弹起时释放能量。

A RAT bungee jump, however, would be a one-way trip. RATS absorb energy when stretched in the way that an elastic¹⁰ substance does,

但RAT弹力绳将是一次单程旅行。当以弹性物质的方式拉伸时，RATS吸收能量，

but, unlike an elastic, they do not then give it back when released. That would leave a jumper dangling¹² at the bottom.

但与弹性物质不同的是，它们在被松开时不会释放能量。这样将会让蹦极者在底部晃荡。

Dr Wetzel's team were developing RATS as ankle supports to absorb landing shock for parachutists

Wetzel博士的团队正在研发RATS作为一种吸收跳伞者着陆时震动力的踝护

when they realised that the tethers they were working with had just the qualities required for helmet suspensions:

当时他们意识到，他们使用的拴绳拥有头盔悬架所需的品质：

they provide instant strong resistance, which increases with impact speed.

它们提供即时强大的抵抗，这增加了冲击速度。

Existing military helmets protect in situations like travel over rough terrain¹³, collisions between vehicles and with obstacles,

现有的军用头盔能够在崎岖地形、车辆和障碍物之间的碰撞

and being thrown around by bomb blasts. RATS offer better protection in all these cases.

以及被炸弹炸得四处乱飞等情况下起到保护作用。

Current American-army combat helmets are built to withstand impact velocities¹⁴ of three metres a second,

目前美国陆军的战斗头盔能够承受3米每秒的冲击速度，

with newer models being rated for just over four. Prototype helmets fitted with RAT suspension pass impact tests at five metres a second,

而最新型号的头盔只能承受4米多每秒的冲击速度。配有RAT悬架的原型头盔以每秒5米的速度通过了撞击测试，

which Dr Wetzel says no previous helmet suspension has achieved.

Wetzel博士说，之前的头盔悬架还没有达到这一水平。

1 maize   

n.玉米

参考例句：

• There's a field planted with maize behind the house.房子后面有一块玉米地。
• We can grow sorghum or maize on this plot.这块地可以种高粱或玉米。

2 starch   

n.淀粉；vt.给...上浆

参考例句：

• Corn starch is used as a thickener in stews.玉米淀粉在炖煮菜肴中被用作增稠剂。
• I think there's too much starch in their diet.我看是他们的饮食里淀粉太多了。

3 solidifies   

（使）成为固体，（使）变硬，（使）变得坚固( solidify的第三人称单数 )； 使团结一致； 充实，巩固； 具体化

参考例句：

• Jelly solidifies as it gets cold. 肉冻冷却就凝固。
• It is stirred with 10%sodium carbonate solution(50ml)and then with water (50ml), after which It'solidifies. 与10％碳酸钠溶液（50毫升）混合搅拌，然后再用50毫升水混合搅拌，从而析出固体。

4 armour   

（=armor）n.盔甲；装甲部队

参考例句：

• His body was encased in shining armour.他全身披着明晃晃的甲胄。
• Bulletproof cars sheathed in armour.防弹车护有装甲。

5 concussion   

n.脑震荡；震动

参考例句：

• He was carried off the field with slight concussion.他因轻微脑震荡给抬离了现场。
• She suffers from brain concussion.她得了脑震荡。

6 foam   

v./n.泡沫，起泡沫

参考例句：

• The glass of beer was mostly foam.这杯啤酒大部分是泡沫。
• The surface of the water is full of foam.水面都是泡沫。

7 straps   

n.带子( strap的名词复数 )；挎带；肩带；背带v.用皮带捆扎( strap的第三人称单数 )；用皮带抽打；包扎；给…打绷带

参考例句：

• the shoulder straps of her dress 她连衣裙上的肩带
• The straps can be adjusted to suit the wearer. 这些背带可进行调整以适合使用者。

8 fabric   

n.织物，织品，布；构造，结构，组织

参考例句：

• The fabric will spot easily.这种织品很容易玷污。
• I don't like the pattern on the fabric.我不喜欢那块布料上的图案。

9 viscous   

adj.粘滞的，粘性的

参考例句：

• Gases are much less viscous than liquids.气体的粘滞性大大小于液体。
• The mud is too viscous.You must have all the agitators run.泥浆太稠，你们得让所有的搅拌机都开着。

10 elastic   

n.橡皮圈，松紧带；adj.有弹性的；灵活的

参考例句：

• Rubber is an elastic material.橡胶是一种弹性材料。
• These regulations are elastic.这些规定是有弹性的。

11 elasticity   

n.弹性，伸缩力

参考例句：

• The skin eventually loses its elasticity.皮肤最终会失去弹性。
• Every sort of spring has a definite elasticity.每一种弹簧都有一定的弹性。

12 dangling   

悬吊着( dangle的现在分词 )； 摆动不定； 用某事物诱惑…； 吊胃口

参考例句：

• The tooth hung dangling by the bedpost, now. 结果，那颗牙就晃来晃去吊在床柱上了。
• The children sat on the high wall,their legs dangling. 孩子们坐在一堵高墙上，摇晃着他们的双腿。

13 terrain   

n.地面，地形，地图

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• He knows the terrain of this locality like the back of his hand.他对这一带的地形了如指掌。

14 velocities   

n.速度( velocity的名词复数 )；高速，快速

参考例句：

• In experimenting we find out that sound travels with different velocities through different substances. 在实验中，我们发现声音以不同的速度通过不同的物质而传播。 来自《现代汉英综合大词典》
• A gas in thermal equilibrium has particles of all velocities. 处于热平衡的气体，其粒子有一切速度。 来自辞典例句