科学美国人60秒 狗教炸弹嗅探机新把戏

（单词翻译）

Old Yeller was a great smeller. Dogs in general have superior smelling abilities. They detect dead bodies, illegal drugs and explosives—even cancer. But dogs don't just have great olfactory¹ gear. Another reason they're amazing chemical detectors³? [sniffing⁵ sound] … is the sniff⁴.

老黄狗(来自电影《老黄狗》)嗅觉非常的灵敏。一般而言，狗具有优越的嗅觉。它们可以发现尸体、毒品、炸药——甚至癌症。但是狗狗们并不仅仅拥有强大的嗅觉器官。另外一个原因就是它们还具有神奇的“化学探测器”?那就是嗅。

"And it turns out almost every breed of dog does this at 5 Hz. Five times a second." Matthew Staymates, a mechanical engineer and fluid dynamicist⁶ at the National Institute of Standards and Technology. Sniffing, he says, is really a two-part process. “Inspiration, expiration⁷, right? Inhale⁸, exhale⁹, inhale, exhale." That second part, the exhale, is key.

“结果表明，几乎每个品种的狗吸气的频率都是5赫兹。即一秒钟5次。”Matthew Staymates是美国国家标准与技术研究院的机械工程师和流体动力学家。他表示，嗅是有两个过程。“吸气和呼气?”吸气，呼气，吸气，呼气。第二部分，呼气才是关键。

"So when the dog is actively¹⁰ sampling or sniffing on the ground, there is a turbulent air jet that exits each nostril¹¹ during the exhale phase. Just like when you and I exhale there's an air jet that comes out of our nostrils¹². But the dog is down on the ground and those air jets are vectored down and toward its rear. And in the world of fluid dynamics¹³, if I pulse an air jet in one direction I basically pull air with it." So the dog is creating a pressure differential that effectively pulls new scents¹⁵ toward its nose.

“当狗狗在地上嗅赖嗅去的时候，在它呼气的时候，每个皮孔都会喷出紊流空气。就像我们呼气的时候，我们的鼻孔就会有气流喷出。但是狗狗是附身嗅地面，呼出的空气流会反冲会自己的呼吸器官。在流体动力学领域，如果我们呼出空气流是朝一个方向，最后，也会吸入这个空气流。”所以，狗狗在制造一种压力差，可以使鼻子嗅出新的气味。

Staymates and his colleagues discovered that effect using a 3-D–printed model of a Labrador retriever's nose, which they tested with fluid dynamics equipment. They then outfitted¹⁶ a commercial vapor¹⁷ detector² with sniffing nostrils, inspired by the dog nose. And they found that the actively sniffing detector was 16 times better at picking up the scent¹⁴ of explosives, compared to just continuously drawing in air—the usual method. The results are in the journal Scientific Reports.

Staymates和同事们利用拉布拉多猎犬鼻子的3维模型研究了效果并用以检测流体动力学设备。受到狗嗅觉的启发，他们在商业蒸汽探测器上也安装了“嗅觉”装置。结果发现，与通常的方法——仅持续的吸入气流相比，这种嗅觉设备在识别炸药气味上更加卓越。该研究结果发表在《科学报告》杂志上。

Staymates says he hopes next-generation sensors¹⁸ take sniffing seriously. "There's nanosensors out there that can detect very, very small amounts of materials. One of the things that's been overlooked: is how do you get the molecules¹⁹ of interest to the detector? So you can have the most sophisticated detector in the world, but unless you can get material to it, it's not very useful." Adding a sniffer though…could be just the thing to make those detectors more dogged.

Staymates表示，希望下一代的传感器可以认真考虑嗅觉装置。有的纳米传感器可以进行精微检测。但有一点被人们所忽视：“如何获得分子探测器?这样你就可以拥有世界上最先进的探测装置，或许装置不太实用，但是前提是你得拥有装置材料。”只添加一个嗅觉装置，就可以让那些感应器更加的灵敏。