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Water is among the most abundant compounds in the universe.
水是宇宙中最丰富的化合物之一。
It makes up about 70 percent of the Earth's surface and about 60 percent of our bodies.
地球表面约70%是水，人体约60%是水。
And the odds are pretty good that you've already encountered a bunch of it today.
很可能今天你就已经接触到水了。
But despite how common water is, it continues to baffle scientists because it behaves unlike anything else out there.
但是，尽管水很常见，它仍然困扰着科学家，因为它的表现不同于其他任何东西。
Seriously, water is way weirder than you'd think. First off, liquid water.
说真的，水比你想象的要奇怪得多。首先，液态水。
You know, the super familiar stuff you drink and wash your hands with.
这是大家超级熟悉的东西—喝的和洗手用的。
Yeah, turns out, liquid water is complicated.
是的，液态水很复杂。
Because it seems to have not one, but two liquid phases that occur at the same time.
因为它似乎不是一个，而是两个液相同时发生。
This likely happens at very low temperatures and high pressures —
这很可能发生在非常低的温度和高压下——
around -45 degrees Celsius and 2400 times the normal atmospheric pressure. So, it's not something you'd encounter every day.
大约摄氏零下45度，是正常大气压的2400倍。所以，这不是你每天都会碰到的东西。
Regardless, under these conditions, water can spontaneously split into two liquid phases
不论如何，在这种情况下，水可以自发地分裂成两个共存的液相，
that coexist like the oil and vinegar in your salad dressing: in separate layers, each with its own density.
就像沙拉酱里的油和醋一样：在不同的层，每一层都有自己的密度。
The low-density portion is made of the standard tetrahedral pattern of water molecules,
低密度部分由标准的四面体水分子组成，
where a central molecule is linked to four neighbors.
其中一个中心分子与四个相邻分子相连。
But the high-density liquid has an extra molecule trying to squeeze into the group.
但高密度液体有一个额外分子试图挤进群体中。
So far, scientists have only observed this in a computer model,
到目前为止，科学家们只是在计算机模型中观察到这一点，
partly because, well, those temperature and pressure conditions are timely and expensive to replicate.
部分原因是，那些温度和压力条件是及时的，而且复制起来很昂贵。
But if this idea holds up in physical experiments, it could help explain water's other weird properties.
但如果这一观点在物理实验中站得住脚，那么它将有助于解释水的其他奇怪属性。
Like how ice has regions of low and high density, which is how it floats on water.
比如，冰的密度有高有低，所以它能漂浮在水面上。
These regions could somehow be frozen remnants of the two liquid phases.
这些区域可能是两种液相的残余部分。
And if so, the two densities could help us develop a model that predicts
如果是这样的话，这两种密度可以帮助我们建立一个模型，
how water will behave from super cold temperatures to the ones we experience all the time.
预测水从极冷的温度到我们常用水温的变化历程。
Since water is such an integral part of our world, a model like that could be useful for all sorts of research. So, not too shabby!
由于水是我们世界不可获取的部分，这样的模型可以用于各种各样的研究。所以模型做好点！
Moving out of the liquid phase, we have our next weird thing: Scientists can't figure out when water starts to act like a glass.
讲完液相，水还有另一件奇怪的事情：科学家们不知道水何时开始像玻璃杯一样活动。
If that sentence sounded weird... yeah, that's fair. Because the glass phase is a weird one.
如果这句话听起来很奇怪……没错，是很奇怪。因为玻璃相很奇怪。
It's a sub-state between solid and liquid, where water can exist... well, like glass.
它是处于固体和液体之间的亚态——水可以像玻璃一样存在。
In short time scales, it looks like a solid, but in reality, it's very slowly relaxing into a liquid state.
在短时间内，它看起来像固体，但实际上，它正在非常缓慢地放松成液体状态。
Water isn't the only substance with a glass phase, but how it gets there seems to be unique.
水不是唯一具有玻璃相的物质，但它的形成方式似乎是独一无二的。
Typically, as other substances are heated, they experience a gradual increase in heat capacity,
一般来说，当其他物质被加热时，它们的热容会逐渐增加，
which is the amount of heat needed to raise their temperature one degree Celsius.
这是使它们的温度升高1摄氏度所需要的热量。
Their heat capacity continues to rise until it reaches the glass transition temperature, where it suddenly jumps 100% higher.
它们的热容继续上升，直到达到玻璃化转变温度，此时它突然跃升100%。
At which point, it's officially in the glass phase.
在这一刻，它正式进入了玻璃相。
But as water is heated, its heat capacity barely changes until all of a sudden it crystallizes and becomes a solid.
但当水加热时，它的热容几乎没有变化，直到它突然结晶变成固体。
This has made it difficult for scientists to pin down a glass transition temperature.
因此，科学家难以确定玻璃转变温度。
Right now, they think it happens somewhere around -123 to -53 degrees Celsius.
现在，他们认为它发生在-123到-53摄氏度之间。
But it's been so hard to figure out anything more specific that they've dubbed this window "no man's land."
但是很难找到更具体的细节，所以他们把这个空窗称为“无人区”。
At this point, it's not totally clear what's going on, but at a minimum,
此时，我们不完全清楚发生了什么，但至少
this tells us that something about water's heat capacity isn't normal.
这告诉我们水的热容是不正常的。
That its temperature doesn't change like we'd expect.
它的温度不会像我们期望的那样变化。
Scientists have been looking into it, though, because understanding water's glass phase could really come in handy.
科学家们一直在调查，因为了解水的玻璃相真的可以派上用场。
After all, this form of water is actually the most abundant in the universe and appears in a number of places,
毕竟，水的这种形式实际上是宇宙中最丰富的且形式多样，
even in space aboard interstellar dust particles.
甚至在星际尘埃颗粒的太空中。
So, uncovering the secrets of glassy water could help us understand how it forms and shapes our solar system.
因此，揭开玻璃水的秘密可以帮助我们了解它是如何形成并塑造了我们的太阳系的。
Of course, once you move past regular H2O, things start getting even weirder.
当然，一旦你超过了正常的H2O，事情就变得更加奇怪了。
Like, apparently, you can't explain exactly how water acts in your body without involving quantum mechanics.
比如，显然如果不涉及量子力学，你无法准确解释水在你体内的作用。
Scientists reported this in a 2019 paper, where they were studying mixtures of water and charged polymers.
科学家们在2019年的一篇论文中报告了这一点，当时他们正在研究水和带电聚合物的混合物。
These kinds of solutions are found in your joints, and they're really thick and viscous; much more than you'd expect.
这种溶液存在于关节中，非常粘稠；比你想象的要多得多。
Which is helpful for your knees, but overall, kind of confusing.
这种物质对你的膝盖有帮助，但总的来说，有点令人疑惑。
For a while, we thought this viscosity was caused by repulsive interactions between the polymers,
曾有一段时间，我们认为这种粘性是由聚合物之间的排斥性相互作用造成的，
where similar electric charges repelled each other. But in their paper, this team found there's much more to the story.
相似的电荷相互排斥。但在他们的论文中，团队发现并不仅仅如此。
They discovered that the polymers' electric charge also affected how water molecules were interacting with each other.
他们发现聚合物的电荷也会影响水分子相互作用的方式。
These interactions made water's hydrogen bond network more ordered.
这些相互作用使水的氢键网络更加有序。
And that made it hard for molecules to move and hindered the flow of the solution, therefore making it more viscous!
并且这也使得分子很难移动，并阻碍了溶液的流动，因此使溶液更加粘稠！
That by itself was a cool result,
这本身就是一个很酷的结果，
because it showed you can't treat water as a neutral background for chemistry like we sometimes tend to do.
因为这表明你不能像我们有时做的那样把水当作化学的中性背景。
It's an active molecule you need to pay attention to. But what's stranger is what this team found next.
这是一个大家需要注意的活性分子。但更奇怪的是这个团队接下来的发现。
In their study, they also looked at solutions of charged polymers and heavy water.
在他们的研究中，他们还研究了带电聚合物和重水的溶液。
That's water made of oxygen and deuterium, a form of hydrogen with twice the usual mass.
那是由氧和氘构成的水，氘是氢的一种形式，质量是通常的两倍。
This solution behaved a lot differently than the one with normal water.
这种溶液的表现与正常的水有很大的不同。
The molecules interacted in different ways, and the viscosity was different.
分子以不同的方式相互作用，粘度也不同。
In fact, these changes were so significant, they couldn't actually be explained with traditional chemistry models.
实际上，这些变化非常显著，所以不能用传统的化学模型来解释。
Instead, the team concluded you need to consider quantum mechanics to fully understand them.
该团队转而总结道，你需要考虑量子力学才能完全理解它们。
It's hard to say exactly how the quantum world comes into play here.
很难说量子世界是如何在这里发挥作用的。
But ultimately, the team suspects these effects influence how hydrogen bonds break in each type of water,
但最终，研究小组怀疑这些效果会影响每一种水的氢键断裂方式，
because that would affect the viscosity of the solutions.
因为这会影响溶液的粘度。
So, water can't be ignored, and it's way more complicated than it seems on the surface.
所以水是不能被忽视的，而且它比表面上看起来要复杂得多。
But learning more about how this all works could help us learn more about applications for polymers solutions
但是更多地了解这一切是如何工作的，可以帮助我们更多地了解聚合物溶液的应用，
and how water behaves in our bodies.
以及水在我们体内的行为。
Because of its abundance and how big of a role it plays in our universe, we can take water for granted. But it's really strange stuff.
由于水的丰富和它在我们的宇宙中所扮演的重要角色，我们可以把水视为理所当然。但水真的很奇怪。
And understanding why can help us advance lots of scientific fields.
理解其中原因可以帮助我们推进许多科学领域。
So the next time you take a swig of water or see a raincloud, know that you're looking at something truly extraordinary.
所以下次你喝水或看到一朵雨云时，要知道你看到的是真正非凡的东西。
Speaking of extraordinary… let me tell you about our patrons on Patreon.
说到非凡，我想说说我们Patreon上的赞助人。
We say it a lot around here, but we really can't thank our patrons enough.
我们在这里经常这么说，但是我们真的非常感谢我们的赞助人。
Their support literally makes this show happen, and they're a community of smart, curious, wonderful people.
有他们的支持，才有我们的节目，他们是一群聪明、有好奇心且非常棒的人。
So if you're a patron, thank you! And if you want to join our Patreon community
如果你是我们的赞助人，那么谢谢你！如果你想加入我们的社区，
and support free science education online, we'd love to have you. You can learn more at Patreon.com/SciShow.
并支持我们的在线科学教育，我们很高兴有你的加入。你可以在Patreon.com/SciShow上了解更多。
