Narrator: Listen to part of a lecture in a materials science class.

旁白：请听材料科学的一部分讲座。

Professor: So what's the first thing that comes to mind when we talk about uses for copper? Tammy?

教授：那么，当我们谈论铜的用途时，我们想到的第一件事是什么？Tammy？

Student: The penny. It's made of copper.

学生：一分钱。它是由铜制成的。

Professor: Okay, good one.

教授：非常好。

But what's a one cent coin worth these days?

但是现在一个一分钱硬币值什么呢？

You might get back change.

你可能会得到一些找零。

Like if you go to the store and give the cashier 5 dollars for something that costs 4 dollars 98 cents, you'll get 2 cents back, but 2 cents does not buy much.

就像你去商店，给收银员5美元，买一些花费4美元98美分的东西，你会得到2分钱找零，但2分钱买不了什么。

The value of the penny in terms of what it'll buy has gotten so low that there's actually a move afoot to eliminate the coin from US currency.

从购买力来说，一分钱的价值已经变得如此之低，以至于事实上有了一个这样的举动，就是从美国货币当中消除一分硬币。

But there's more to it.

但这里还有更多的东西。

As Tammy implied, the penny looks like it's solid copper.

正如Tammy所暗示的，一分钱看起来像是固体铜。

It is reddish orange with a bright metallic luster when it's new, but that's just the copper plating.

当它是新的时候，它是红橙色的，有一个明亮的金属光泽，但这只是电镀铜。

The penny's not solid copper.

一分钱不是固体铜。

In actuality, it is almost 98 percent zinc.

实际上，它几乎是98％的锌。

But, um, given the rising value of both these metals, each penny now costs about 1.7 cents to produce.

但是，嗯……鉴于这两种金属的价值上涨，每一分硬币现在要花费1.7美分来制作。

So it generates what is called negative Seigniorage.

所以它产生了所谓的负铸币税。

Negative seigniorage is when the cost of minting a coin is more than the coin's face value.

负铸币税是指铸造硬币的成本大于硬币的面值。

Even though the penny generates quite a bit of negative seigniorage, there is concern that if it's eliminated, we'll need more nickels, because more merchants might start setting prices in five-cent increments, 4 dollars 95 cents and so on.

虽然一分钱产生了相当多的负铸币税，但有人担心，如果它被淘汰，我们将需要更多的5美分镍，因为更多的商人可能开始以5美分的价格增量开始定价，如4美元95美分等。

So we need a trusty five-cent piece that can be minted economically.

所以我们需要一个可靠的五分钱可以被经济地铸造。

But the nickel's negative seigniorage is even worse than the pennies. Each nickel costs the US mint 10 cents to produce.

但是，五分镍币的负铸币税甚至比便士更糟。 每一块五分镍币都花费美国10美分铸币。

Also, some of us are pretty attached to pennies for whatever reason, nostalgia, and then those collectors.

此外，我们有些人非常喜欢便士，无论什么原因，可能怀旧，还有那些收藏家。

And people, if they see a penny on the sidewalk, they'll pick it up and think: it is my lucky day!

而人们如果在人行道上看到一分钱，便会拾起来，认为：这是我的幸运日！

Another scenario is that, without pennies, merchants, instead of charging 4.98, might round up the price to an even five dollars.

另一种情况是，没有便士，商人，可能会把价格定成整数到甚至五美元，而不是4.98。

So consumer goods would become slightly more expensive.

所以消费品会变得稍贵一些。

But on the other hand, some cash transactions would be more convenient for consumers.

但另一方面，一些现金交易对消费者来说更方便。

And as I said, the government would save money if pennies were eliminated.

正如我所说，如果消除了便士，政府将会省钱。

Student: But wouldn't the copper industry suffer financially if the US government stopped buying copper to make pennies?

学生：但是，如果美国政府停止购买铜来制造便士的话，铜工业不会在财政上受到影响吗？

Professor: But how much copper do pennies actually contain?

教授：但是便士里实际包含多少铜呢？

Student: How much... Oh, got it, right.

学生：多少……哦，明白了，对。

Professor: So what else comes to mind when you think about copper?

教授：那么，当你想到铜时还能想到什么其它的呢？

What else is copper used for?

铜还能用来干嘛？

Student: I know that copper can be shaped into all sorts of things: sheets, tubing, and my cousin's house has a copper roof.

学生：我知道铜可以塑造成各种各样的东西：板材，管材，我表弟的房子有一个铜屋顶。

Professor: Yes, like gold and silver, copper is extremely malleable, but it's not a precious metal, it's far less expensive than gold or silver.

教授：是的，像金和银，铜也是极具延展性的，但它不是一种贵金属，远没有金或银昂贵。

It's also a superb conductor of electricity so you can stretch it into wires which go into appliances and even car motors.

它也是一个极好的电导体，因此你可以将它拉成线，用于电器甚至汽车发动机。

Copper also has superior alloying properties, it's... you know, when it's combined with other metals.

铜还具有优良的合金化性能，它……你知道，当它与其它金属结合的时候。

For instance, how many of you play a brass instrument, like a trumpet or a trombone?

例如，你们中有多少人演奏铜管乐器，如小号或长号？

Well, brass is an alloy of copper and zinc.

嗯，黄铜是铜和锌的合金。

If your trombone was made of pure copper or pure zinc, it wouldn't sound nearly as beautiful as a brass trombone.

如果你的长号是纯铜或纯锌，它不会听起来像黄铜长号那么动听。

Another alloy, a combination of copper and nickel, resists corrosion.

另一种合金，铜和镍的组合，抗腐蚀。

It does not rust, even with prolonged exposure to water.

它不生锈，即使长期暴露于水。

Student: But what about the Statue of Liberty in New York Harbor?

学生：但是在纽约港的自由女神像呢？

It's made of pure copper, but it turned green.

它是由纯铜制成，但它变成绿色。

Isn't that a sign of corrosion?

这不是腐蚀的迹象吗？

Professor: Indirectly. If copper's exposed to damp air, its color changes from reddish orange to reddish brown.

教授：间接地。如果铜暴露在潮湿的空气中，其颜色从红橙色变成红棕色。

But in time, a green film, called a patina, forms and the patina actually serves to halt any further corrosion.

但是，随着时间的推移，一个绿色的膜形成，称为铜绿，铜绿实际上用于停止任何进一步的腐蚀。

It is one reason that ship hulls are made of copper-nickel alloys.

这是为什么船体由铜-镍合金制成的一个原因。

These alloys are also hard for the barnacles to stick to.

这些合金使藤壶粘附也变得困难。

If these little shellfish adhere to the hull of a ship, it produces drag, slowing the vessel down.

如果这些小贝类附着在船体上，会产生阻力，使船只减速。

Copper's also a key material used in solar heating units and in water desalination plants, which will play increasingly important roles in society.

铜也是太阳能加热单元和海水淡化工厂中使用的关键材料，它将在社会中发挥越来越重要的作用。

Bottom line: if you are a copper miner, you won't lose any sleep should the penny get. If you'll excuse the expression, pinched out of existence.

总结一下：如果你可以接受这种说法的话，那么假如你是一名矿工，你不会因为便士的消失而损失任何睡眠（因为担忧失业而感到焦虑）。