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

近年来，家们分析了这些外来物通过放射性同位素衰减测其年龄。

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

但在这个岛上，近亲结婚是个大问题，人口也正在衰减。

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

当岩石融化并重形成时，所有衰减的证据都被摧毁了。

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

我打量着她的前额，看那上面会不会偶然出现一个皱纹，告诉我她正在衰减的热情。

Or you can even talk about the opposite, which is exponential decay.

或者你也可讨论其反面，即指数衰减。

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

亮度衰减需要一定的时间。

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" 位元衰减" 。

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减?

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

光在水中会衰减。所海豚和其他齿鲸类动物在水中用回声定位，就像蝙蝠一样。

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减。

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减。

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

它们的衰减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，保存着各种通常衰减的有机物质。

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上有很多士兵守卫，乍得的商业活动将继续衰减。

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减成铅的速度可用来计算他们的年龄。

Compared to electricity or radio, fiber optic signals barely degrade over great distances.

与电力或无线电信号相比，光纤信号在长距离传输中几乎不会衰减。

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

恰好一半样本衰减所需的时间。

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

第二个线索是，这个阴影对高频声音的衰减比对低频声音的衰减更大。

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减而减弱。

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

到了白天，衰减要大一个数量级。