Devices that detect potentially hazardous gases or airborne environmental pollutants are out there.
虽然有能够检测潜在有害气体或空气中环境污染物的设备。
But they're expensive and bulky.
但它们一直价格昂贵而且体积笨重
Now M.I.T. researchers say they've developed a way to get the same detection abilities—with your smartphone.
而现在麻省理工学院的研究人员们已经研发出了一种同样能够进行检测的方法—那就是利用智能手机。
The research team modified what are called near-field communication tags, or NFC tags.
这个研究小组修改了被称为近场通信标签的NFC标签。
Smartphones with NFC capabilities send out magnetic field pulses.
具有NFC功能的智能手机会发出磁场脉冲。
The magnetic field creates an electric current on the tag that the phones pick up.
而这种磁场会在手机接收的标签上产生电流。
Such systems are typically used to track products or drugs.
这样的系统通常用于追踪产品或药物。
For the new application, the scientists added links to the circuit made of carbon nanotubes.
而对于这样一款新应用程序,科学家们在碳纳米管制成的电线回路加上了链接。
Each link responds to one particular gas, by changing how the nanotubes conducts electricity.
通过改变纳米管的导电方式,每个链接都对应一种特定气体。
By sensing the change in electric current on the tag,the smartphone signals that it has detected the gas in question.
通过感应标签上的电流变化,智能手机信号就会检测到问题气体。
The method was tested with ammonia, cyclohexanone and hydrogen peroxide.
这种方法已经经过氨气,环己酮及过氧化氢的检验。
And the tags could sense the substances at levels of a few parts per million.
而且这些标签可以在每百万的极少物质中感应到问题物质。
The research is in the Proceedings of the National Academy of Sciences.
这项研究已经在《美国国家科学院院刊》上发表。
Such inexpensive tiny tags require no external power.
这种廉价的小标签不需要外部电力。
The scientists say their NFC tag system has the potential to be widely used to monitor gases that can affect health, safety and the environment.
科学家们表示他们所研发的这种NFC标签系统可能在未来会被广泛用于监测影响健康、安全和环境的气体。