2021年经济学人 新款集水网--天网恢恢,疏而不漏(1)

Water supply

供水

A better fog trap

更好的雾网

A clever upgrade of a humble¹ but useful technology

一种不起眼但有用的技术的聪明升级

Every night, air cooled and moistened by the Humboldt current blows over Chile's northern coast and across the Atacama desert. The billowing banks of fog thus created might look insubstantial, but there is water here to be captured—and in this, the driest place on Earth, capture it people do. Fog-harvesting will never be big business, for it needs particular conditions to operate well. But in zones like the Atacama, where moisture-laden breezes bring fog but no rain, the invention in the 1960s of traps which can pluck that moisture from the air has helped sustain settlements otherwise on the brink² of drought.

每天晚上，洪堡洋流吹过智利北部海岸和阿塔卡马沙漠，使空气变得凉爽、湿润。由此产生的滚滚大雾可能看起来并不真实，但这里有水可以收集——在这里，在这个地球上最干燥的地方，人们是这样做的。雾收集永远不会成为大生意，因为它需要特殊的条件才能运作良好。但在像阿塔卡马这样的地区，潮湿的微风带来雾，但没有雨，20世纪60年代发明的网可以从空气中吸收水分，帮助维持住在干旱边缘的定居点。

Fog traps are polymer-mesh³ screens mounted in metal frames. As misty⁴ zephyrs⁵ blow through them, droplets⁶ of water adhere to the mesh. These absorb others until the result breaks free and runs down the screen, as a raindrop runs down a window pane⁷, into a collector. A typical trap, with a 40-square-metre collecting area, yields about 200 litres a day. That is enough to supply around 60 people with drinking water. Such a collector costs $1,000 or so, and will last a decade.

雾网是安装在金属框架上的聚合物网屏。当雾蒙蒙的和风吹过它们时，水滴就会粘在网孔上。它们吸收其他物质，直到释放出来并沿屏幕流下，就像雨滴沿窗玻璃流下，进入收集器。一个典型的雾网有40平方米的收集面积，每天可以产出约200升的水，足以为大约60人提供饮用水。这样的雾网价值约1000美元，可以用10年。

A simple idea, then. But even simple technology can be upgraded. And that is exactly what Urszula Stachewicz of the AGH University of Science and Technology, in Krakow, Poland, proposes to do.

这是一个简单的想法，但即使是简单的技术也可以进行升级。而这正是波兰克拉科夫AGH科技大学的厄休拉·斯塔切薇兹打算做的。

Her upgrade relies on giving the mesh a slight electrical charge. Overall, the molecules⁹ in it are electrically neutral. But polymer molecules are large, and their electrons can move about within them. Uneven¹⁰ distribution of these electrons means some parts of a molecule⁸ are positive and some negative. That fact might be exploited to give the outside of each thread in a mesh one electrical polarity (either positive or negative) while burying the other polarity in the thread's interior. Just as static electricity will attract a balloon to a wall, a surface charge created in this way will attract water droplets from the air.

她的升级方法是给网眼轻微的电荷。总的来说，它的分子是电中性的。但是聚合物分子很大，它们的电子可以在其中移动。这些电子的不均匀分布意味着分子的某些部分带正电，某些带负电。这一事实可能会被利用来给网中的每条线的外部一个电极性(无论是正的或负的)，而把另一个极性埋在线的内部。就像静电会把气球吸引到墙上一样，用这种方法产生的表面电荷也会吸引空气中的水滴。

1 humble   

adj.谦卑的，恭顺的；地位低下的；v.降低，贬低

参考例句：

• In my humble opinion,he will win the election.依我拙见，他将在选举中获胜。
• Defeat and failure make people humble.挫折与失败会使人谦卑。

2 brink   

n.(悬崖、河流等的)边缘，边沿

参考例句：

• The tree grew on the brink of the cliff.那棵树生长在峭壁的边缘。
• The two countries were poised on the brink of war.这两个国家处于交战的边缘。

3 mesh   

n.网孔，网丝，陷阱；vt.以网捕捉，啮合，匹配；vi.适合； [计算机]网络

参考例句：

• Their characters just don't mesh.他们的性格就是合不来。
• This is the net having half inch mesh.这是有半英寸网眼的网。

4 misty   

adj.雾蒙蒙的，有雾的

参考例句：

• He crossed over to the window to see if it was still misty.他走到窗户那儿，看看是不是还有雾霭。
• The misty scene had a dreamy quality about it.雾景给人以梦幻般的感觉。

5 zephyrs   

n.和风，微风( zephyr的名词复数 )

参考例句：

• If you but smile, spring zephyrs blow through my spirits, wondrously. 假使你只是仅仅对我微笑，春天的和风就会惊奇的吹过我的心灵间。 来自互联网

6 droplets   

n.小滴( droplet的名词复数 )

参考例句：

• Droplets of sweat were welling up on his forehead. 他额头上冒出了滴滴汗珠。 来自辞典例句
• In constrast, exhaled smoke contains relatively large water droplets and appears white. 相反，从人嘴里呼出的烟则包含相当大的水滴，所以呈白色。 来自辞典例句

7 pane   

n.窗格玻璃，长方块

参考例句：

• He broke this pane of glass.他打破了这块窗玻璃。
• Their breath bloomed the frosty pane.他们呼出的水气，在冰冷的窗玻璃上形成一层雾。

8 molecule   

n.分子，克分子

参考例句：

• 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。

9 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。

10 uneven   

adj.不平坦的，不规则的，不均匀的

参考例句：

• The sidewalk is very uneven—be careful where you walk.这人行道凹凸不平—走路时请小心。
• The country was noted for its uneven distribution of land resources.这个国家以土地资源分布不均匀出名。