Over the years, scientists have analysed these meteorites and determined their age through radioactive dating.

年来，科学家们分析了这些外来物通过放射性同位素衰测其年龄。

But inbreeding was a big problem on the island and the population is dying out.

但在这个岛，结婚是个大问题，人口也正在衰。

And when rocks melt and reform anew, all evidence of that decay is destroyed.

当岩石融化并重新形成时，所有衰的证据都被摧毁了。

I scanned her brow for any passing line that might indicate a settling emotion.

我打量着她的前额，看那面会不会偶然出现个皱纹，告诉我她正在衰的热情。

It takes a certain amount of time for that brightness to dissipate.

亮度衰需要定的时间。

When digital information in an image or audio recording cannot be read, it is called a bit rot.

当图像或音频中的数字信息无法读取时，它就被称为" 位元衰" 。

ALESCI : How much of a setback was the outbreak in 2006 of E. coli?

2006年爆发的大肠杆菌疫情有多大程度的衰?

Light doesn't travel well underwater. So dolphins and other toothed whales navigate like bats, using echolocating clicks.

光在水中会衰。所以海豚和其他齿鲸类动物在水中用回声定位，就像蝙。

Unfortunately, men, we don't go to the doctor, for the most part, unless something is falling off.

不幸的是，我们不都不会选择看医生，除非真的出现功能衰。

Iranian media say President Rouhani is to announce his country's commitment to the 2015 nuclear deal is diminishing.

伊朗媒体称，鲁哈尼总统即将宣布伊朗对2015年核协议的执行度将会逐渐衰。

Their collapse is being driven by human activity, everything from traffic to industrial farming and pesticides to light pollution.

它们的衰是由人类活动造成的，包括从交通到工业化农场，从杀虫剂到光污染。

And the water in the channel keeps the oxygen out, preserves all sorts of organic materials that normally decay.

河道中的水将氧气挡在外面，保存着各种通常衰的有机物质。

He says business activity in Chad will continue to decrease, even with many soldiers on roads and in markets.

他说尽管路边和市场有很多士兵守卫，乍得的商业活动将继续衰。

First, their content of radioactive uranium decays to lead at a rate that can be used to calculate their age.

首先，他们的放射性铀含量衰成铅的速度可以用来计算他们的年龄。

The time it takes for exactly one half of the sample to decay.

恰好半本衰所需的时间。

And the second cue is that this shadow attenuates higher frequencies more than low frequencies.

第二个线索是，阴影对高频的衰比对低频的衰更大。

Next, Neil and his colleagues modeled the sound-dampening capabilities of an array of different scales.

霍普金：接下来，尼尔和他的同事们模拟了系列不同规模的声音衰能力。

Reverb in a natural setting tends to fade as the audio signal decays.

自然环境中的混响会随着音频信号的衰而弱。

By day, the attenuation is an order of magnitude greater.

到了白天，衰要大个数量级。

713. We had a rapid airspeed decay due turbulence.

713. 由于湍流，我们的空速迅速衰。