How do we separate the seemingly inseparable? - Iddo Magen

譯者: Ann Chen 審譯者: Max Chern

Your cell phone is mainly made of plastics and metals.

你的手機主要是用塑膠及金屬做成的

It's easy to appreciate the inventive process

我們很容易領會這發明過程

by which those elements are made to add up to something so useful and entertaining.

是把這些東西加起來 做成有用又有趣的物品

But there's another story we don't hear about as much.

但另有一種我們不常聽到的事

How did we get our raw ingredients in the first place

首先，我們如何從許多混亂物質 所構成的自然界中取出原料呢？

from the chaotic tangle of materials that is nature?

The answer is a group of clever hacks known as separation techniques.

答案就在一組聰明的小技巧， 所謂的「分離技術」

They work by taking advantage of the fundamental properties of things

它們是利用物質的基本特性運作

to disentangle them from each other.

將物質內的原料彼此分開

Simple separation techniques apply to many physical scenarios,

簡單的分離技術 可用在許多物理情況

like separating cream from milk,

例如從牛奶中分離奶油

extracting water from soil,

從土壤裡抽取水

or even sifting out flecks of gold from river sand.

甚至從河砂中篩出黃金微粒

But not all mixtures are so easy to unravel.

但並非所有混合物都如此容易分開

In some of those cases,

在某些情況

we can exploit the differences between physical properties within a mixture,

我們可利用混合物成分間 不同的物理特性

like particle size,

像顆粒大小、密度或沸點

density,

or boiling point

to extract what's required.

以分離出我們所需

Take petroleum,

例如石油

a mixture of different types of hydrocarbons.

是一種不同烴類（碳氫化合物）的混合物

Some of these are valuable as fuels,

其中有些是極有價值的燃料

and others make good raw materials for generating electric power.

而其他可做為生產電力的上等原料

To separate them, experts rely on one important feature:

要將它們分開， 專家利用一種重要特性：

different hydrocarbons boil at different temperatures.

不同烴類在不同溫度達到沸點

During the boiling process, each type vaporizes at a precise point,

在煮沸過程， 每一種會在其精確溫度下蒸發

then gets separately funneled into a container

然後分別匯集到儲油罐

and collected as a liquid as it cools.

當冷卻時就結成液體

Separation techniques also take us to the sea.

分離技術也讓我們的話題轉到海洋

In some drought-stricken countries,

一些深受乾旱之苦的國家

the ocean is the only available water source.

唯一可用的水源就是海洋

But of course, humans can't drink salt water.

但當然，人不能飲用鹽水

One way to get around this problem

處理這問題的一個方法

is to remove salt from sea water with reverse osmosis,

就是用逆滲透 (Reverse osmosis, RO) 從海水中除去鹽

a process that separates water's ingredients by size.

RO 是依水中成分大小不同 將其分離的步驟

A membrane with pores bigger than water particles,

一個具有孔隙比水分子大， 比鹽分子小的薄膜

but smaller than salt particles,

only lets fresh water pass through,

只容淡水通過

transforming what was once undrinkable into a life saver.

將原先不能喝的水變成維生用水

Meanwhile in the medical world,

同時，在醫學界

blood tests are a vital tool for evaluating a person's health,

血液檢查 是評估一個人健康的重要方法

but doctors typically can't examine blood samples

但醫師通常無法檢驗血液檢體

until they've separated the solid blood cells

除非將固態的血球細胞

from the liquid plasma they're dissolved in.

和其溶入的液態血漿分開

To do that, a powerful rotational force is exerted on the test tube,

為此，會在檢驗試管上 施加強勁的旋轉力

causing heavier substances with higher density,

造成密度較高的較重物質

like blood cells,

如血液細胞

to move away from the rotational axis.

遠離旋轉軸

Meanwhile, lighter substances with lower density,

同時，密度較低的較輕物質

like plasma,

如血漿

move to its center.

移向試管中心

The tube's contents divide clearly,

試管內容物會清楚地分開

and the blood cells and liquid plasma can be tested independently.

因此血液細胞及液態血漿 可各自被檢測

But sometimes, unlike oil, seawater, and blood,

但有時，不同於油、海水及血液

the parts of mixtures that we want to separate

我們要分離的混合物成分

share the same physical properties.

有著相同的物理特性

In these cases, the only way to isolate ingredients is by chemical separation,

這情況下，分開成分的唯一方法 就是化學分離法

a complex process that relies on unique interactions

它是一種複雜程序， 需依賴混合物的成分

between components within a mixture and another material.

與另一物質的成分之間 特有的相互作用

One of these methods is chromatography,

其中一種方法就是 色譜法 (chromatography)

a tool forensic scientists use to examine crime scenes.

一種法醫科學家 用以檢驗犯罪現場的方法

They dissolve gathered evidence in a gas,

他們將採集的証據溶於一種氣體中

and can monitor and analyze the ingredients

並檢測及分析其中成分 ──

as they separate and move at varying speeds

由於每種成分有獨特化學特性， 會分離並且以不同速度移動

due to their unique chemical properties.

That information then tells scientists precisely what was present at the scene,

這訊息讓科學家知道 留在犯罪現場的到底是何物

often helping to identify the culprit.

這常協助辨識罪犯

Separation techniques are not just about industry,

分離技術不只和工業、

infrastructure,

基礎結構、醫學及法律制裁有關

medicine,

and justice.

One of the most technically ambitious projects in human history

在人類史上 對技術最有雄心的計畫之一

is a separation technique aimed at answering the fundamental question,

是分離技術旨在 回答最根本的問題：

"What is the Universe made of?"

「宇宙是什麼組成的？」

By accelerating particles to extremely high speeds

藉著將粒子加到極高速

and smashing them into each other,

而後讓它們互撞碎裂

we can break them into their constituent parts ever so briefly.

我們能讓這些粒子 短暫性分解成組成成分

And if we succeed at that, what's next?

若我們在這方面成功了， 那下一步是什麼？

Is there a most elementary particle?

有最基本的粒子嗎？

And if so, what's it made of?

若有，它是由什麼構成的？

翻譯：Ann Chen