The fascinating science of bubbles, from soap to champagne | Li Wei Tan

翻译人员: Mengjia MA 校对人员: Yolanda Zhang

Some years ago, I was visiting Paris

很多年前我游访巴黎时，

and walking along the Seine River during a beautiful summer afternoon.

曾在一个美好的夏日午后 漫步在塞纳河边。

I saw giant bubbles floating on the riverbank,

我看到一些巨大的泡泡漂浮在河岸，

like this one.

像这个一样。

The next moment, it popped and was gone.

随后，它突然破裂然后消失。

Making them were two street performers surrounded by a crowd.

这是被一群人围住的 两个街头艺人制造出的泡泡，

They visibly make a living by asking for donations

显然他们营生的手段 是靠卖艺获得捐款，

and by selling pairs of sticks tied with two strings.

和售卖一对被两根绳子拴在一起的棍子。

When I was there, a man bought a pair of sticks for 10 euros,

当时，正好一个男人 花了10欧元买了一对棍子，

which surprised me.

这让我感到十分吃惊。

I am a scientist who is passionate about bubbles.

我是一个痴迷于气泡的科学家，

I know the right trick to make the giant bubbles

我知道这些大泡泡背后的把戏，

is the right soapy water mixture itself --

不过是配比合适的 肥皂水的混合物在起作用——

not the sticks,

与棍子无关，

which may be needed,

尽管可能用得到，

but you can easily make them at home.

你在家里也能很容易的做出这些泡泡。

Focusing on the sticks makes us not see that the real tool is the bubble itself.

把焦点放在棍子上让我们忽视了 真实的工具其实就是气泡本身。

Bubbles might seem like something just children make while playing,

或许气泡看起来只是 孩子们玩弄的东西，

but sometimes it can be really stunning.

但有时它的效果十分惊人。

However, there are more fascinating science to bubbles,

然而，这些气泡背后 还有着更为迷人的科学知识，

例如解决问题的工具。

such as problem-solving tools.

So I would like to share with you

所以我想跟你们分享

a few stories about the science of creating bubbles

关于制造气泡的科学故事，

and the science of eliminating the microscopic ones.

和消除微观气泡的科学。

Since it's up on the screen, let's start with the soap bubble.

既然已经在屏幕上显示了， 我们就从肥皂泡开始吧。

It is made from very common substances:

它是由很相似的物质构成的，

air, water, soap, in the right mixture.

空气，水，肥皂，适当的混合，

You can see soap bubbles constantly changing their colors.

你们可以看到肥皂泡不断的变换颜色。

This is due to the interaction with light at various directions

这是由于它与灯光在不同角度相互作用，

and the changes of their thickness.

而且厚度也会发生变化。

One of the common substances, water molecules,

其中一个共同的物质，水分子

are formed by two atoms of hydrogen and one atom of oxygen -- H2O.

是由两个氢原子和 一个氧原子组成的——即 H2O。

On most surfaces, water droplets tend to curve inwards,

在大多数表面上，水滴倾向于向内弯曲

forming a semihemisphere shape.

形成半球形状。

This is because the water droplet's surface is like an elastic sheet.

这是因为水滴的表面富有弹性，

The water molecule on the surface is constantly being pulled inwards

表面的水分子不断地

by the molecule at the center.

被中心的分子拉向内部。

And the quality of the elasticity is what we call "surface tension."

弹性就是我们所说的表面张力。

Now by adding soap,

通过增加肥皂，

what happens is the soap molecule reduces the surface tension of water,

肥皂分子降低了水的表面张力，

making it more elastic and easier to form bubbles.

使得它更具弹性，并且更容易形成气泡。

You can think of a bubble as a mathematical problem-solver.

可以把一个气泡想成 一个数学问题解决者，

You see it relentlessly trying to achieve geometry perfection.

你看到它不断尝试去实现几何学完美，

For instance, a sphere is the shape with the least surface area

例如，对于给定的体积，球体是

for a given volume.

表面积最小的形状。

That's why a single bubble is always in the shape of a sphere.

这就是为什么一个气泡 总是以球体的形态存在，

Let me show you. Check it out.

让我来展示给你们看。

This is a single bubble.

这是一个单一的气泡，

When two bubbles touch each other,

当两个气泡彼此接触，

they can save materials by sharing a common wall.

它们会通过共享球壁来节约材料。

When more and more bubbles are added together,

当越来越多的气泡聚集到一起，

their geometry changes.

它们的几何形状会发生变化。

These four bubbles are added together.

这四个气泡聚集在一起，

They meet at one point at the center.

它们在中心有一个交点。

When six bubbles are added together,

当六个气泡聚集到一起，

a magical cube appears at the center.

一个神奇的立方体就会出现在中心。

(Applause)

（掌声）

That is surface tension at work,

这是表面张力在起作用，

trying to find the most effective geometry arrangement.

试图找到最有效的几何排列。

Now, let me give you another example.

现在，让我们来看另一个例子。

This is a very simple prop.

这是一个非常简单的道具，

This is made from two layers of plastic

它由两层塑料制成，

with four pins connected to each other.

通过四个针钉相互连接。

Imagine these four pins represent four cities that are equally apart,

试想这四个针钉代表了四个等距的城市，

and we would like to make roads to connect these four cities.

我们想修建马路把四个城市连接起来。

My question is: What is the shortest length to connect these four cities?

我的问题是：连接这四个城市 最短的路径是什么？

Let's find out the answer by dipping it into the soapy water.

让我们将其浸入肥皂水中来找出答案。

Remember, the soap bubble forms will always try to minimize

请记住，肥皂泡的形成总是会尽量

their surface area

使表面积最小化，

with a perfect geometry arrangement.

并伴随完美的几何排列。

So the solution might not be something you expected.

所以解决方案或许不是你所期待的那样。

The shortest length to connect these four cities

连接四个城市最短的长度，

is 2.73 times the distance between these two cities.

是两个城市距离的2.73倍。

(Applause)

（掌声）

Now you've got the idea.

现在你已经明白了，

The soap bubble forms will always try to minimize their surface area

肥皂泡的形成总是 尽量使表面积最小化，

with a perfect geometry arrangement.

并伴有完美的几何排列。

Now, let us look at bubbles in another perspective.

现在，让我们用从另一个 角度来看待这些气泡。

My daughter, Zoe, loves visiting zoos.

我的女儿，Zoe，喜欢逛动物园。

Her favorite spot is Penguin Cove at Marwell Zoo in Southern England,

她最喜欢的地方是位于英格兰 南部的马威尔动物园的企鹅湾。

where she could see penguins swim at speed under the water.

在那里她可以看企鹅 在水下飞快的游泳。

One day, she noticed that the body of penguins

有一天，她注意到当企鹅们游泳时，

leaves a trail of bubbles when they swim

它们的身后会留下一串串的气泡，

and asked why.

她向我询问其中原因。

Animals and birds like penguins

动物和鸟类，比如企鹅，

that spend a lot of their time under the water

大部分时间都生活在水里，

have evolved an ingenious way of utilizing the capability of bubbles

逐渐进化出了一种可以利用气泡

to reduce the density of water.

来降低水的密度的巧妙方式。

Emperor penguins are thought to be able to dive a few hundred meters

帝企鹅可以在海平面下几百米深的

below the sea surface.

水下潜水。

They are thought to store the air under their feathers

它们被认为会在潜水前

before they dive

在羽毛下面存储空气，

and then progressively release it as a cloud of bubbles.

然后逐渐释放空气形成一团气泡。

This reduces the density of water surrounding them,

这可以降低它们周围的水的密度，

making it easier to swim through

让游泳变得更轻松，

and speed up their swimming speed at least 40 percent.

同时可以将游泳速度提高至少40%。

This feature has been noticed by the ship manufacturers.

这个特点被船舶制造商注意到了。

I am talking about the big ships here,

我说的是大型船只，

the ones that are used to transport thousands of containers across the ocean.

那些可以跨洋运输 上千个集装箱的大船，

Recently, they developed a system called "air lubricating system,"

他们近来开发了一套 称为“空气润滑系统”的装置，

inspired by the penguins.

就是受企鹅的启发。

In this system, they produce a lot of air bubbles

他们用这个系统制造很多空气泡，

and redistribute them across the whole of the ship,

并重新分散在整只船周围，

like an air carpet that reduces the water resistance

就像一层空气地毯一样，以此来降低

when a ship is moving.

船行时水的阻力。

This feature cuts off the energy consumption for the ship

这个功能为船只节省了

up to 15 percent.

高达15%的能源消耗。

Bubbles can also be used for medicines.

气泡同样也可以用于医药，

It can also play a role in medicines,

它也可以在药物中发挥作用。

for instance, as a method for noninvasive delivery systems for drugs and genes

例如，可以作为将药物和基因 运送至身体的某个特定部位的

to a specific part of the body.

非侵入性传递系统的一种方法。

Imagine a microbubble

想象一个

filled with a mixture of drugs and magnetic agents

充满药物和磁性剂混合物的微泡，

being injected into our bloodstream.

被注入到我们的血液中。

The bubbles will move to the target areas.

气泡会移向目标区域，

But how do they know where to go?

但是它们如何知道要去哪里呢？

Because we placed a magnet there.

因为我们在那放置了一个磁体，

For instance, this part of my hand.

例如，我手上的这个部位。

When the microbubbles move to this part of my hand,

当微泡移到我手上的这个部位，

we can pop it via ultrasound

我们就可以通过超声使它破裂，

and release the drug exactly where it's needed.

并且准确的把药物释放到所需部位。

Now, I mentioned about the science of creating bubbles.

那么，我提到了制造气泡的科学，

But sometimes we also need to remove them.

但是有时我们也需要除去气泡，

That's actually part of my job.

这实际上也是我工作的一部分。

My exact job title is "ink formulation scientist."

我确切的职称是“油墨配方科学家”，

But I don't work on the ink that you use for your writing pens.

但是，我所打交道的不是 你们写字用的笔中的那种油墨，

I'm working on some cool applications

我所用的油墨有着非常酷的应用，

such as organic photovoltaics, OPVs,

如有机光伏，OPV；

and organic light-emitting diodes, OLEDs.

和有机发光二极管，OLED。

Part of my job is to figure out how and why we want to remove the bubbles

我的一部分工作就是搞清楚 我们在油墨生产过程中

from the ink that my company produces.

要消除气泡的方式和原因。

During the formulation-mixing process,

在配方混合过程中，

or preparation process,

或者准备过程中，

我们将活性成分，溶剂 和添加剂混合在一起，

we mix active ingredients, solvents and additives

in order to achieve the formulations with the properties we want

以使配方在墨水使用过程中

when the ink is being used.

实现我们想要的性能。

But just like you would make drinks

但是，就像你做饮品

or bake cakes,

或是烘培蛋糕，

it is unavoidable that some air bubbles will be trapped inside that ink.

一些气泡会不可避免地 进入到油墨中。

Here, we are talking about a different space

在这里，我们谈论的气泡

from the bubbles I'd seen in Paris.

与我在巴黎看到的 有着截然不同的尺度。

The bubbles that are trapped inside those inks

那些困在油墨里的气泡，

vary between a few millimeters,

尺寸在几毫米

a few microns

到几微米不等，

or even a few nanometers in size.

甚至只有几纳米。

And what we are concerned about

我们所关心的是

is the oxygen and the moisture that is trapped inside.

困在里面的氧气和水分。

At this size scale, removing them is not easy.

在这样的尺寸范围里 移除它们并不容易。

But it matters,

但是这很重要，

for instance, for organic light-emitting diodes inks

例如，对于可以用来生产

that we can use to produce display for your smartphone, for example.

智能手机显示屏的有机发光二极管，

It's supposed to last for many years,

它应该十分经久耐用，

but if the ink that we use has been absorbed with oxygen and moisture

但如果我们使用的油墨 掺进了氧气和水分，

[which] are not being removed,

又没能被移除，

then we can quickly see dark spots appear in the pixels.

我们很快就会在像素中看到黑点。

Now, one challenge we face in removing the microbubbles

在移除微气泡的过程中， 我们所面临的一个挑战是，

is that they are not very cooperative.

它们并不配合。

They like to sit there,

它们被固定在油墨中，

bathing in the ink without moving much.

几乎一动不动。

But how do we kick them out?

那我们该如何把它们移走呢？

One technology we use

我们使用的一种技术，

is to force the ink going through a thin, long and tiny tube

就是迫使油墨穿过一根

with a porous wall,

带有多孔壁的细长的管子，

and we place the tubes inside the vacuum chamber,

我们把管子放到真空室内，

so that the bubbles can be squeezed out from the ink

这样气泡就会从油墨中被挤压出来，

and be removed.

进而被移除。

Once we manage to remove the bubbles from the ink that we produce,

在成功的将气泡从所生产的 油墨中移除的那一刻，

it is time for celebration.

我们应该为此庆祝。

Let's open a bubbling champagne.

让我们打开一瓶气泡香槟，

Ooh, this is going to be fun!

喔，这将会非常有趣！

(Laughter)

（笑声）

Woooo!

哇！

(Applause)

（掌声）

You could see a lot of bubbles rushing out from the champagne bottle.

你们可以看到很多泡泡 从酒瓶中喷涌而出，

These are the bubbles filled with carbon dioxide,

这些气泡充满了二氧化碳，

a gas that's been produced during the fermentation process of the wine.

一种在制酒的发酵过程中产生的气体。

Let me pour some out.

让我们倒出一些，

I can't miss the chance.

我可不能错过这样的机会。

I guess it's enough.

应该够了。

(Laughter)

（笑声）

Here, I can see a lot of microbubbles

这里，我可以看到许多微小的气泡，

moving from the bottom of the glass to the top of the champagne.

从杯子的底部向香槟的液面移动。

Before it pops,

在破裂前，

it will jet tiny droplets of aroma molecules

它会喷射出很多香气分子，

and intensify the flavor of champagne,

让香槟的味道更加浓郁，

making us enjoy much more the flavor of champagne.

让我们能够更好的享受香槟的味道。

As a scientist who is passionate about bubbles,

作为一个痴迷于气泡的科学家，

I love to see them,

我喜欢观察这些气泡，

I love to play with them,

与气泡为伴，

and I love to study them.

研究它们。

And also, I love to drink them.

同时，我也喜欢将它们一饮而尽。

谢谢！

Thank you.

(Applause)

（掌声）