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你意想不到的核反应堆做的五件事 – 译学馆
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你意想不到的核反应堆做的五件事

5 Things You Wouldn't Expect a Nuclear Reactor To Do

这里是麻省理工学院核反应堆实验室
Here at the MIT Nuclear Reactor Lab,
在中心位置正进行着核裂变反应 [叮]
we have fission reactions going on in our core [dings]
即意味着铀-235原子
and that means that there are uranium-235 atoms
正分裂成中子 热能和其它更小的原子
that are splitting into neutrons, heatenergy, and other smaller atoms.
动力反应堆利用热能来发电
Power reactors use the heat energyto generate electricity,
但事实证明
but it turns out that
你可以利用裂变反应做更多的事情
there’s so much more that you cando with a fission reactor.
例如 测量多种不同的微量元素
Like, measuring tiny amounts of abunch of different elements.
我们甚至可以检测出头发样品中的砷
We can even measure arsenic in a sample of hair.
为了做这个测试 我把我的头发作为样品
To do this, I take my hair sample,
把它放进这个容器 盖上盖子
place it in this container, put the lid on,
然后把它放入这个管道
and put it in this tube here.
– 从这里- 头发通过管道
– From here- The hair gets sent through the pipes
进入一个紧邻反应堆核心的腔室
into a chamber that’s right next to the reactor core
并在其中俘获中子
where it absorbs some neutrons,
中子能让头发中的砷元素具有放射性
which makes some of the arsenic in the hair radioactive.
在反应堆中放置12小时
After 12 hours in the reactor,
并经历数天的衰变后 我取出样本
and a few days of decay, I take the sample,
把它放进这个铅制容器
put it in this lead container,
铅容器可以保护我免受辐射
to protect me from the radiation,
然后 我要开始分析它了
and I go analyze it.
我把头发样本放到检测器中
I put the hair sample in this detector,
一个非常灵敏的检测器
which is very sensitive.
灵敏到可以检测出我头发中
So sensitive, it measures radiation
单个砷原子发出的辐射
from individual arsenic atoms in my hair.
这个峰值下的区域告诉我们
The area under this peak tells us
样品中有多少砷
how much arsenic is in the sample.
所以 我们的核反应堆能够
So our reactor can tell us if
仅仅通过分析某人的头发来判断
someone’s been exposed to things like arsenic,
他是否接触了砷这样的东西
just by analyzing their hair.
– 它能- 从材料测量出其它方法很难检测的
– It can- Measure very small amounts of a lot of different elements
多种不同的微量元素
in materials that are difficult to measure otherwise.
第二件比较酷的事是
Cool thing number two is that
我们利用反应堆产生的中子束
We’re using the neutron beam produced in our reactor
来观察材料的微观结构
to see the microscopic structure of materials.
裂变反应产生的中子
The neutrons produced by the fission reaction
形成波束 并轰击
come out as a beam and they hit the sample,
放置在这里的样品
which is positioned right here.
当中子束轰击样品时
When the neutron beam hits a sample,
样品就像镜子一样 将中子反射到各个方向
the sample acts like a mirror, reflecting the neutrons in all different directions.
在这个鼓状物中 有个检测器
Inside this drum, there’s a detector that
可以检测各方位上中子反射的方向和数量
measures the different directions and number of neutrons reflected in each direction
– 这个- 实际上可以告诉我们
– and this- Can actually tell us
样品中原子是如何排列的
how the atoms are positioned inside our sample.
所以 这里的x轴是
So on the x-axis here is
探测器相对于样品的角度
the angle of the detector with respect to the sample,
而y轴是检测器探测到的中子数
and on the y-axis is the number of neutrons the detector sees.
所以 在这个位置上有很多的中子
So, this position, there are a lot of neutrons,
每秒几乎有1400个中子 而在这 大概只有600个
almost 1400 per second, and overhere, there are about 600.
在这里 几乎没有中子
Down here, there are almost no neutrons.
因此 借助这些数字
So, using these numbers,
我们可以弄清楚材料中原子的排列
we can figure out how atoms arearranged inside of a material.
其它反应堆的科学家
Scientists at other reactors
希望利用这种技术来研究不同类型核燃料
want to use this method to see howthe atomic structure
在进入反应堆后原子结构是怎么变化的
of different nuclear fuels changewhile they’re used in a reactor.
观察这些变化可以帮助我们改进出新型的
Seeing these changes can help us develop new,
更安全的 并且更加高效的核燃料
safer, and more efficient types of nuclear fuel.
– 并且- 使用中子是让我们
– And- Using neutrons is the only way
观察这些原子结构变化的唯一途径
that we can see these changes in atomic structure.
使用常规显微镜或是其他任何方法
You wouldn’t be able to see the same thing
你都看不到这些结构变化
with a regular microscope or any other method.
– 第三件 我们可以将金子- 变成抗癌的工具
– Number three, we can turn gold- Into tools to fight cancer.
我们首先将很小的金粒
We start by loading tiny seeds of gold
装入一个叫做兔子的支架
into a holder that we call a rabbit.
那么 我将把兔子带到我们的
So, I’ll take the rabbit over to one
一个隔离工作区
of our shielded work areas,
在这里 我们可以将兔子插入反应堆
where we can insert the rabbit into the reactor.
[欢快的键盘音乐声]
[upbeat keyboard music]
现在我要把金粒送到反应堆核心旁边
And now I’m gonna send the goldseeds next to the reactor core.
它们进到那
They go in there where
俘获中子 然后会变得带有辐射
they’ll absorb neutrons and become radioactive.
将它们放在其中几分钟后
After they stay in there for a few minutes,
我们将其取出 然后密封好
we send them back out and package them up.
我们将其密封并把金粒
We package them up and move the gold seeds
放入铅容器中
into a lead container.
– 现在的金粒具有放射性 而且- 事实上
– The gold seeds are now radioactive and – The fact that
它的放射性实际是个好事情 因为医生将要
it’s radioactive is actually a good thing because doctors are gonna
把这些金粒注射进肿瘤中
take those gold seeds and inject them into a tumor,
而这些金粒的放射性将杀死这些癌细胞
and it’s the radiation from the gold that’s gonna kill those cancer cells.
– 第四件- 反应堆做的另一件酷事是
– Number four, – Another cool thing our reactor does is,
帮助我们为飞机 火车站和混合动力汽车等
we help create electronic components for things like
制造电子元器件
airplanes, train stations, and hybrid cars.
目前 这块硅是不导电的
Right now, this silicon does not conduct electricity,
但我可以通过将其放入反应堆来改变它
but I can change that, by loading it into the reactor.
[欢快的键盘音乐声]
[upbeat keyboard music]
好了 刚刚在我身后发生的是
OK, so what’s happening behind me is that
我刚刚放置的硅片正穿越一个安装在
the silicon piece that I just loaded istraveling through a tube
反应堆核心下方的管道
that runs underneath the reactor core.
它一旦到达反应堆核心下方
Once it’s under the reactor core,
就会受到裂变产生的中子轰击
it gets bombarded with neutronsfrom the fission process.
某些硅原子俘获了一个中子
Some of the silicon atoms absorb a neutron
然后转化为磷原子
and transform into phosphorous.
正是这个磷原子使材料成为
It’s this phosphorous that makes the material
性能良好的半导体
a really good semi-conductor.
这是进入反应堆之前硅片的样子
This is what the silicon looks likebefore it goes into the reactor,
而这是成为电子器件后的硅片
and this is what goes into electronics.
反应堆以超级精准的操控方式
The reactor turns the silicon into a semi-conductor
将硅转变成半导体
in a super precise and controlled way.
我就是从这里控制的
Which I control from over here.
这就是我们在关键部件中使用半导体的原因
That’s why we use these semi-conductors in mission critical components,
例如电网 还有你们的手机
like the power grid, and not your cell phone.
最后压轴的一件事是
And last, but not least.
我们测试能在未来制造更好更安全的反应堆材料
We test materials that can make safer and better reactors in the future.
今天早上 我们用一种特殊的盐对核反应堆
This morning, we put an experiment into our reactor
进行了一场实验
with a special type of salt.
我们的反应堆 和世界上几乎所有的反应堆一样
So, our reactor, like almost all reactors in the world,
都用水进行冷却
uses water to cool it.
而这种盐的特别之处就在于当它
The special thing about this salt is that it can run
工作在比水高得多的温度时
at much higher temperature than water
仍能保持液态
and still be a liquid.
而不会沸腾
It doesn’t boil.
所以如果用盐取代水做冷却剂 核反应堆将
So a reactor using salt as coolant, instead of water,
能够达到更高的温度
can go to much higher temperature.
从而 反应堆的效率
And the efficiency of a reactor
将因工作温度的提高而变得更好
gets better the hotter it runs,
并且 由于没有水 那么就没有蒸汽
and because there’s no water, there’s no steam,
也就意味着我们不再需要
which means you don’t need to have
用厚墙和大型管道来保证反应堆的安全
Thicker walls and bigger pipes tokeep the reactor safe.
因此 实验中我们将盐放到反应堆堆芯处
So, the salt in our experiment isdown in the reactor core,
然后在实验中 我们将盐
and this experiment’s gonna let us take that salt,
加热到与一个全尺寸的
heat it up to the same temperatures that would be
含盐的核反应堆堆芯相同的温度
inside the core of a full-size salt reactor,
进而使其带有
and then hit it with the same kind of radiation
与盐反应堆核心一样的放射性
that it would see in the core of a salt reactor.
当盐受到辐射后
As you hit the salt with radiation,
盐是会转变成截然不同东西呢
does it produce different productsthat come out of the salt
还是以某种方式改变了盐的特性呢?
or does it change the salt in certain ways?
这个盐实验将要在我们的反应堆
This salt experiment is gonna be in our reactor
进行大约1000小时
for about a thousand hours,
但我们并非只研究这一种东西
but that’s not the only thing we study.
我们还研究不同的材料 燃料 甚至传感器
We also look at different materials,fuels, and even sensors,
当它们进入反应堆中心后的变化
to go inside the core of reactors.
我们所做的一切研究都是为了
All of this research is working towards making
使未来的核反应堆能够变得更加安全 更加高效
reactors safer and more efficient in the future.

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视频概述

人们普遍认为核反应堆只是用来发电的,而本视频将通过五件事告诉我们,核反应堆还能被用来做什么。

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视频来源

https://www.youtube.com/watch?v=1kq1LpkB6WQ

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