美国国家公共电台 NPR Say Au Revoir To That Hunk Of Metal In France That Has Defined The Kilogram

 

DAVID GREENE, HOST:

So every time you weigh something, whether it's coffee or bananas - I'm not sure what you're weighing - you might be doing it in pounds - well, whatever you're doing, you're unknowingly relying on a global system of measurement that has this long and storied history. That history is about to enter a new chapter. For the first time in more than a century, scientists are about to redefine the kilogram. Here's NPR's Nell Greenfieldboyce.

NELL GREENFIELDBOYCE, BYLINE¹: I wanted to get up close and personal with the kilogram, so I went to Maryland to the National Institute of Standards and Technology, our nation's premier² agency for the science of measurement. In a building there, there's a massive elevator.

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GREENFIELDBOYCE: It takes me down to a basement. I have to put on a hairnet, booties, a white lab coat. Zeina Kubarych unlocks a door to a secure, climate-controlled lab. Only a few keys exist.

ZEINA KUBARYCH: Three people have access to this room.

GREENFIELDBOYCE: Over in a corner, I see small cylinders⁴ of a silver-looking metal. It's actually a platinum-iridium alloy⁵ - the sexy, futuristic material of the 19th century. That's when these cylinders were forged. Each cylinder³ is under two old-fashioned glass bell jars.

KUBARYCH: So these are our national standard kilograms.

GREENFIELDBOYCE: They are exact copies of the official kilogram held in France - a hunk of metal that is kept in a vault⁶ outside of Paris. Its weight is the definition of a kilogram - a little over two pounds. This piece of metal is simply called the kilogram or, affectionately, Le Grand K. After signing the Treaty of the Meter in 1875, the U.S. got these two copies of it.

KUBARYCH: That's what we use as the basis of our mass dissemination⁷ system in the United States.

GREENFIELDBOYCE: Let's say you're in the supermarket and the cashier weighs your bag of apples. You only know the scale is accurate because the state measurement lab checked it using a certified⁸ mass. How does the state lab know that its certified masses are the correct weight? Because they sent them here to Maryland to be compared to our nation's kilograms. Who else turns to this lab? Pharmaceutical⁹ companies, airplane manufacturers, makers¹⁰ of scientific instruments, anybody who needs to make sure their precise measurements aren't out of whack¹¹.

KUBARYCH: It pretty much spans most of the sectors¹² of the U.S. industry.

GREENFIELDBOYCE: Our national kilograms occasionally get flown to France to be compared to Le Grand K. I would say they get the white glove treatment, but...

KUBARYCH: We don't touch them. We don't even try to touch them with gloved hands.

GREENFIELDBOYCE: Kubarych says the metal artifacts are carefully picked up with a special tool wrapped in filter paper. A tiny scratch in the metal or a fingerprint¹³ could throw off the weight. And that is the big problem with basing your entire system on comparing pieces of metal. If Le Grand K gets heavier or lighter¹⁴, if it absorbs atoms of something from the air, then the definition of the kilogram literally¹⁵ changes. And that, theoretically, affects every single measurement of mass in the world that is based on it. Scientists believe this has been happening. Le Grand K seems to now weigh slightly less than its official copies - a difference that's like a tiny fraction of the weight of a snowflake. Still, for folks who are really into this stuff, this is disturbing. Maybe some teeny fluctuation¹⁶ won't matter to you when you buy your coffee, but in the world of science, it's a disaster to try to understand reality using measurements that are constantly shifting. So on November 16, there will be a vote. The General Conference on Weights and Measures will meet in Versailles. This international group is expected to redefine the kilogram. Kubarych is going just to watch.

KUBARYCH: It's fantastic. It's great. It's history in the making. We are changing a mass realization¹⁷ system that we've had for 129 years. This is a huge event.

GREENFIELDBOYCE: The new kilogram will be based on fundamental, unchanging constants of nature - the speed of light, the vibrations¹⁸ of a cesium atom used to tick off time and Planck's constant, which is central to quantum physics. Stephan Schlamminger has been working hard at another lab here to make that happen.

STEPHAN SCHLAMMINGER: I think what we do here now is we finish something that has begun probably before French Revolution.

GREENFIELDBOYCE: Way back in those revolutionary times, Enlightenment thinkers hated the world's hodgepodge of measurement systems, each one based on some random¹⁹ object like the local duke's foot. Their radical²⁰ vision was to create something rational and universal or, as they put it...

SCHLAMMINGER: For all times for all people.

GREENFIELDBOYCE: The result was the metric system. Its measurement of length, the meter, was already redefined decades ago.

SCHLAMMINGER: So the meter, at some point, was also an artifact.

GREENFIELDBOYCE: The meter was literally a metal bar in France. Its length was supposed to be one ten-millionth of the distance from the North Pole to the equator. Schlamminger says as physics advanced, scientists were able to ditch the metal bar and define the meter in terms of unalterable features of the universe.

SCHLAMMINGER: You just defined a meter as the distance that light travels in one over 300-millionth of a second. And this is the idea of going from artifact to a fundamental constant.

GREENFIELDBOYCE: Now, it's finally the kilogram's turn. Researchers spent years creating an elaborate kind of new scale.

SCHLAMMINGER: Let's walk inside here.

GREENFIELDBOYCE: Schlamminger shows me a device the size of a small car with all kinds of shiny metal parts. In the future, to see if a hunk of metal really weighs one kilogram, it can just go in here. Schlamminger and two of his colleagues are so devoted²¹ to redefining the kilogram that they recently had the numbers of Planck's constant tattooed²² on their bodies. Jon Pratt shows me his tattooed arm. He says convincing the world to switch to a new kilogram was really hard.

JON PRATT: There were plenty of committees and fisticuffs and hemming²³ and hawing on this, so we knew what we were in for. We knew that it was going to be painful, and we all agreed we'd get inked with the number when we got it done.

GREENFIELDBOYCE: He expects the vote on Friday to be unanimous, and humanity will finally be free from the unbearable²⁴ uncertainty²⁵ of Le Grand K.

Nell Greenfieldboyce, NPR News.

(SOUNDBITE OF SONG, "I WANT YOU (SHE'S SO HEAVY)")

BEATLES: (Singing) Heavy, heavy, heavy...

1 byline   

n.署名；v.署名

参考例句：

• His byline was absent as well.他的署名也不见了。
• We wish to thank the author of this article which carries no byline.我们要感谢这篇文章的那位没有署名的作者。

2 premier   

adj.首要的；n.总理，首相

参考例句：

• The Irish Premier is paying an official visit to Britain.爱尔兰总理正在对英国进行正式访问。
• He requested that the premier grant him an internview.他要求那位总理接见他一次。

3 cylinder   

n.圆筒，柱(面)，汽缸

参考例句：

• What's the volume of this cylinder?这个圆筒的体积有多少？
• The cylinder is getting too much gas and not enough air.汽缸里汽油太多而空气不足。

4 cylinders   

n.圆筒( cylinder的名词复数 )；圆柱；汽缸；（尤指用作容器的）圆筒状物

参考例句：

• They are working on all cylinders to get the job finished. 他们正在竭尽全力争取把这工作干完。 来自《简明英汉词典》
• That jeep has four cylinders. 那辆吉普车有4个汽缸。 来自《简明英汉词典》

5 alloy   

n.合金，(金属的)成色

参考例句：

• The company produces titanium alloy.该公司生产钛合金。
• Bronze is an alloy of copper and tin.青铜是铜和锡的合金。

6 vault   

n.拱形圆顶，地窖，地下室

参考例句：

• The vault of this cathedral is very high.这座天主教堂的拱顶非常高。
• The old patrician was buried in the family vault.这位老贵族埋在家族的墓地里。

7 dissemination   

传播,宣传,传染(病毒)

参考例句：

• The dissemination of error does people great harm. 谬种流传，误人不浅。
• He was fully bent upon the dissemination of Chinese culture all over the world. 他一心致力于向全世界传播中国文化。

8 certified   

a.经证明合格的；具有证明文件的

参考例句：

• Doctors certified him as insane. 医生证明他精神失常。
• The planes were certified airworthy. 飞机被证明适于航行。

9 pharmaceutical   

adj.药学的，药物的；药用的，药剂师的

参考例句：

• She has donated money to establish a pharmaceutical laboratory.她捐款成立了一个药剂实验室。
• We are engaged in a legal tussle with a large pharmaceutical company.我们正同一家大制药公司闹法律纠纷。

10 makers   

n.制造者，制造商（maker的复数形式）

参考例句：

• The makers of the product assured us that there had been no sacrifice of quality. 这一产品的制造商向我们保证说他们没有牺牲质量。
• The makers are about to launch out a new product. 制造商们马上要生产一种新产品。 来自《简明英汉词典》

11 whack   

v.敲击，重打，瓜分；n.重击，重打，尝试，一份

参考例句：

• After years of dieting,Carol's metabolism was completely out of whack.经过数年的节食，卡罗尔的新陈代谢完全紊乱了。
• He gave me a whack on the back to wake me up.他为把我弄醒，在我背上猛拍一下。

12 sectors   

n.部门( sector的名词复数 )；领域；防御地区；扇形

参考例句：

• Berlin was divided into four sectors after the war. 战后柏林分成了4 个区。 来自《简明英汉词典》
• Industry and agriculture are the two important sectors of the national economy. 工业和农业是国民经济的两个重要部门。 来自《现代汉英综合大词典》

13 fingerprint   

n.指纹；vt.取...的指纹

参考例句：

• The fingerprint expert was asked to testify at the trial.指纹专家应邀出庭作证。
• The court heard evidence from a fingerprint expert.法院听取了指纹专家的证词。

14 lighter   

n.打火机，点火器；驳船；v.用驳船运送；light的比较级

参考例句：

• The portrait was touched up so as to make it lighter.这张画经过润色，色调明朗了一些。
• The lighter works off the car battery.引燃器利用汽车蓄电池打火。

15 literally   

adv.照字面意义，逐字地；确实

参考例句：

• He translated the passage literally.他逐字逐句地翻译这段文字。
• Sometimes she would not sit down till she was literally faint.有时候，她不走到真正要昏厥了，决不肯坐下来。

16 fluctuation   

n.(物价的)波动，涨落；周期性变动；脉动

参考例句：

• The erratic fluctuation of market prices are in consequence of unstable economy.经济波动致使市场物价忽起忽落。
• Early and adequate drainage is essential if fluctuation occurs.有波动感时，应及早地充分引流。

17 realization   

n.实现；认识到，深刻了解

参考例句：

• We shall gladly lend every effort in our power toward its realization.我们将乐意为它的实现而竭尽全力。
• He came to the realization that he would never make a good teacher.他逐渐认识到自己永远不会成为好老师。

18 vibrations   

n.摆动( vibration的名词复数 )；震动；感受；（偏离平衡位置的）一次性往复振动

参考例句：

• We could feel the vibrations from the trucks passing outside. 我们可以感到外面卡车经过时的颤动。
• I am drawn to that girl; I get good vibrations from her. 我被那女孩吸引住了，她使我产生良好的感觉。 来自《简明英汉词典》

19 random   

adj.随机的；任意的；n.偶然的(或随便的)行动

参考例句：

• The list is arranged in a random order.名单排列不分先后。
• On random inspection the meat was found to be bad.经抽查，发现肉变质了。

20 radical   

n.激进份子，原子团，根号；adj.根本的，激进的，彻底的

参考例句：

• The patient got a radical cure in the hospital.病人在医院得到了根治。
• She is radical in her demands.她的要求十分偏激。

21 devoted   

adj.忠诚的，忠实的，热心的，献身于...的

参考例句：

• He devoted his life to the educational cause of the motherland.他为祖国的教育事业贡献了一生。
• We devoted a lengthy and full discussion to this topic.我们对这个题目进行了长时间的充分讨论。

22 tattooed   

v.刺青，文身( tattoo的过去式和过去分词 )；连续有节奏地敲击；作连续有节奏的敲击

参考例句：

• He had tattooed his wife's name on his upper arm. 他把妻子的名字刺在上臂上。 来自《简明英汉词典》
• The sailor had a heart tattooed on his arm. 那水兵在手臂上刺上一颗心。 来自《现代英汉综合大词典》

23 hemming   

卷边

参考例句：

• "Now stop hemming and hawing, and tell me about it, Edward. "别再这个那个的啦，跟我说说吧，爱德华。 来自英汉文学 - 败坏赫德莱堡
• All ideas of stopping holes and hemming in the German intruders are vicious. 一切想要堵塞缺口和围困德国侵略军的办法都是错误的。

24 unbearable   

adj.不能容忍的；忍受不住的

参考例句：

• It is unbearable to be always on thorns.老是处于焦虑不安的情况中是受不了的。
• The more he thought of it the more unbearable it became.他越想越觉得无法忍受。

25 uncertainty   

n.易变，靠不住，不确知，不确定的事物

参考例句：

• Her comments will add to the uncertainty of the situation.她的批评将会使局势更加不稳定。
• After six weeks of uncertainty,the strain was beginning to take its toll.6个星期的忐忑不安后，压力开始产生影响了。