Rubidium and Strontium then Yttrium, Zirconium.

铷和锶，然后是钇、锆。

But another thing that's cool about it is that, most strontium doesn't start out as strontium.

但另一件很酷的事情是，大多数锶刚开始并不是这种元素。

And the common ones in glow in the dark toys are zinc sulfide and strontium aluminate.

而夜光玩具中常见的有硫化锌和铝酸锶。

But it left behind a slurry of other elements, including types of radioactive strontium, caesium, and technetium.

但它留下了其他元素，包括放射性锶、铯和锝。

For one thing, there's more than one isotope — or form — of strontium.

一方面，锶的同位素或形式不止一种。

And then, the strontium you eat and drink gets incorporated into your teeth!

然后，你吃的和喝的锶会进入你的牙齿！

But another thing that’s cool about it is that, most strontium doesn’t start out as strontium.

但另一件很酷的事情是，大多数锶并不是以锶开始的。

For one thing, there’s more than one isotope -- or form -- of strontium.

一方面，锶的同位素或形式不止一种。

It’s not getting any more new calcium, so the strontium ratio is set forever.

它不再获得任何新的钙，所以锶的比例永远不变。

Strontium, man: It knows where you've been.

锶，伙计：它可知道你去过哪里哦。

It's not getting any more new calcium, so the strontium ratio is set forever.

它不再获得新的钙，因此锶的比例永远固定了。

The enamel coating your teeth contains lots of calcium, and strontium is like calcium in a lot of ways.

牙齿上的牙釉质含有大量钙，锶在很多方面都和钙非常类似。

Strontium, man: It knows where you’ve been.

锶，伙计：它知道你去过哪里。

Strontium aluminate is more expensive, but it has a longer persistence, which means it emits visible light more slowly, and glows longer after being energized.

铝酸锶价格较贵，但持久性较长，这意味着它发出可见光的速度较慢，充电后发光时间更长。

Both the strontium and caesium emit high levels of beta rays, a kind of ionizing radiation, as well as a lot of heat.

锶和铯都会发出大量的β射线（一种电离辐射）和热量。

Your teeth hold a lot of information about your life story, and scientists are learning how to read it, thanks to the properties of strontium.

由于锶的特性，你的牙齿包含了很多关于你的生活故事的信息，科学家们正在研究如何阅读这些信息。

All you'd need to do is let me borrow a couple of teeth, so I could measure how much of the element strontium is in them.

你需要做的就是借我几颗牙齿，这样我就可以测量它们中锶元素的含量。

They use ytterbium or strontium – atoms that oscillate at visible light frequencies – and sync up lasers to the atomic oscillations for timekeeping.

他们使用镱或锶——以可见光频率振荡的原子——并将激光与原子振荡同步以进行计时。

For example, there was the leaking of highly radioactive water in 2016, and strontium and other radioactive substances were found to have exceeded normal standard in 2018.

例如，2016 年发生了高放射性水泄漏，2018 年发现锶等放射性物质超标。

A few years ago, NIST built a strontium clock that broke the world record for precision – that’s how accurately a clock tracks atomic oscillations.

几年前，NIST 制造了一个锶时钟， 打破了世界精度记录——这就是时钟跟踪原子振荡的准确程度。