(单词翻译:单击)
听力文本
Water laced with heavy metals—like the drinking water in Flint, Michigan—can be stripped of contaminants using chemicals, filters, membranes, even electric current.
But now researchers say they've created what could be a cheaper, more effective solution:
a fleet of microscopic, self-propelled, aquatic robots.
Each one the size of just 10 lined-up bacteria—so tiny that a billion will fit in a syringe.
Each tube-shaped microbot is a sandwich of three materials.
A graphene outer layer, which binds to heavy metals.
A middle layer of nickel, which gives the bots magnetic polarity, so they can be pulled through wastewater with magnets.
And platinum inside—for propulsion.
Just add a bit of peroxide to the wastewater, and it'll react with the platinum to form water and oxygen bubbles, which propel the tubes along.
In an hour, a swarm of 200,000 bots scavenged 80 percent of the lead from three millimeters of tainted water.
And the researchers estimate that it costs only about five cents a liter to do so.
The findings are in the journal Nano Letters.
The researchers envision the bots as a portable solution for small companies—they'd treat their water onsite instead of carting it to a treatment plant.
And after the robots do the rounds, the heavy metals can be stripped away.
Meaning companies can reuse the heavy metals, and, ultimately, keep them out of our waterways.
参考译文
像是密歇根州弗林特市饮用水中含有的重金属可以通过化学制品、过滤装置、薄膜，甚至是电流去除。
但现在研究人员表示他们已有了一种价格更为低廉、更行之有效的方法:
那就是一支极微小的、自主驱动的水中机器人部队。
每个机器人约为10排细菌大小—这样小的体积可以在一支注射器中容纳10亿个。
每个管状的机器人是由三种材料构成。
外层的石墨烯可以吸附重金属。
中间的镍层提供磁极性，这样在磁力作用下机器人可以从废水中脱离。
而最里层的铂金具有推动作用。
只需在废水中添加一点过氧化氢，它就会与铂金反应形成推动机器人前进的水和氧气泡沫。
仅在一小时内，20万个这样的机器人就在3毫米的污水中净化了80%的铅。
而研究人员估计这次清理只花费了5美分。
这项研究已在《纳米快报》杂志上发表。
研究人员设想将这种机器人打造成为小型公司准备的便携式解决方案，这样就可以现场净化污水，而不需要运送污水。
而且机器人净化处理后，从水里的重金属就已经被去除了。
这意味着公司可以对重金属再利用，直到最后完全从我们的水道中去除。
译文为可可英语翻译，未经授权请勿转载！
重点讲解
1.bind to 结合
例句:These may bind to receptor molecules on the surfaces of cells.
这些可能会在细胞表面和受体分子结合在一起。
2.heavy metal 重金属
例句:We studied the heavy metal pollution of surface water, Xuzhou.
文章对徐州市地表水体底泥重金属的污染特征进行了研究。
3.magnetic polarity 磁场极性
例句:The second dating method was palaeo-magnetic analysis, or magnetic polaritystratigraphy.
第二种测定法是古磁学分析法，也叫磁极地层学测定法。
4.react with 反应
例句:It's natural to react with disbelief if your child is accused of bullying.
如果你的孩子被指责欺负了别的孩子，你不相信是很正常的。
