They are difficult to detect by sonar because they have soft bodies with no skeleton.

巨型乌贼很难被声纳发现因为它们有柔软的身体而且没有骨骼。

youdao

This makes them harder to move quickly and relatively easy to detect by satellite images.

这使得他们难以快速移动，而且通过卫星图片较易被发现。

youdao

Fortunately, then, evolution has equipped mammals with the ability to detect by smell chemicals whose concentrations vary with differences in the MHC of the producer.

幸运的是，生物进化赋予哺乳动物通过嗅觉对MHC进行分辨的能力，因为MHC的不同导致了化学物质浓度的差异，而这时可以被嗅觉探测到的。

youdao

And the Air Force currently uses radar developed by DeTect at several bases.

VOA: special.2009.04.01

So this project was, let's see if we can detect any alpha particles by making a detector that swings around.

当你是本科生的时候，你们的导师会派一些,你们看上去很傻的工作,给你们干，现在这个工作就是。

麻省理工公开课 - 化学原理课程节选

The radar is built by the company DeTect of Panama City,Florida.

VOA: special.2009.04.01

Such potency makes the substance hard to detect by chemical analysis, which lacks the sensitivity of the nose.

ECONOMIST: Wine

Fortunately, then, evolution has equipped mammals with the ability to detect by smell chemicals whose concentrations vary with differences in the MHC of the producer.

ECONOMIST: Perfume science

Dealers sometimes try to make fake profiles harder to detect by randomly following some famous and some average people, or posting tweets grabbed from the Twitter stream.

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