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  • element 41 is now you be, um, on dhe I'd ever seen.

  • Now you be, um, until recently and then I was lent a medal.

  • I haven't won the medal, but it is a medal that is given each year to somebody who's made a real contribution to the field of Now you be, um, chemistry or no, you be, um, science.

  • The medal is made out of.

  • Now you be, um So look carefully.

  • This is metallic.

  • Maybe, um, I can't remember who won it last year, but it has been won by Syria's of people, mostly in the field of metallic ji.

  • And I'll explain the whites metallic Gee wrote in chemistry.

  • In a minute, I was lent this by the company Cbmm, which awards this medal together with the Institute of Materials and Minerals.

  • It is named after Charles Hatchet, who was the English scientist who discovered no, you beom will discover the element initially on dhe is really quite interesting.

  • It was the beginning of the 19th century, just after the idea of elements had being published.

  • So everybody was looking for elements, and Charles Hatchet looked at a mineral which had been in a museum in London for quite a long time Mineral that came from America, and he discovered a new element.

  • And because it came from America, he called it Columbia, MME.

  • Because Columbia isn't the Latin name that is often used for America, and I think the name Columbia, um sounds really beautiful, you it only really opposed to naming elements after countries.

  • Well, I think it's quite nice when its name by somebody who doesn't come from that country, then it's a genuine honor rather than a patriotic gesture.

  • And, of course, England had just lost the American colonies, so it was particularly nice gesture.

  • Hatchet, unfortunately, didn't continue as a chemist, and he worked in a company that made carriages.

  • I suppose, the modern equivalent of a sports car company and later in his career he focused on the carriage is rather than on science.

  • The element was then rediscovered in Germany and name.

  • Now you be, um, there was a problem because the Americans called it Columbia.

  • The Europeans called it niobium, and there was a sort of trade off.

  • It was agreed the Americans would call it Night opium if the Germans and the Europeans would call Wolfram Constant.

  • So everybody was happy.

  • But now you been is actually a relatively abundant at element compared to many of the metals.

  • And the by far the biggest deposit is in Brazil, where this company's Cbmm is a mining company that digs Now you be amount to the ground now the main used for now you be, um, at the moment is in strengthening steel steel for making bridges, steel for making cars, steel for making pipelines that you use for high pressure gas like natural guests.

  • So imagine this piece of paper is steel.

  • If the steel was just a single crystal, if you put 1/4 on it like my pulling here, it would be very strong.

  • But actually the steel consists of small SoCal grains rather like small crystals.

  • The boundary between the grains is the weak point.

  • So let me illustrate that by tearing the paper of it now you can see if I pull again.

  • When there's this weak point, it does pulls apart for easily.

  • So the grain boundaries is what causes the failure on the pipe bursts.

  • If you don't make it thick enough, if you had just a tiny bit of niobium to the steel less than 0.1 of a percent less than one part in the thousands.

  • The niobium concentrates along the grain, boundary and strength and sit, Let me show you analogy again.

  • So here we've got two grains and you can see this weak point in between.

  • But now, if if you imagine the night you Veum across this grain boundary, it forms a block so that when you pull it, it's much stronger and it doesn't break.

  • I'm pulling really hard.

  • What this means is that if you had a small amount of nayu beom to your pipe to the steel that you make your pipe, you can put a lot more gas through the same pipe.

  • There's a pipe in China which is 8000 kilometres long, and by adding sin, maybe, um on making the pipe a little heavier one and 1/4 times heavier.

  • You can take two and 1/2 times as much gas down the same pipe in calls.

  • The car's in developed countries like the U.

  • S.

  • And in Europe they add about 200 grams of niobium to this steel that makes up the car, and that saves 100 kilos of weight of steel in that car.

  • It's almost the weight of a whole passenger.

  • And so then when you're driving every 100 kilometers, also that you drive, that saves one or two liters of petrol, depending how aggressively you drive, Professor.

  • How does adding Nairobi and make the car Lotte where it makes the car lighter?

  • Because the CIA steel is stronger, so you don't need so much steel to make the same strength car.

  • But you said the party was made heavier and child, that's what other things.

  • Well, you made it heavier by little bit, and then you could take twice as much gas in it in the car.

  • You just want to take the same number of passengers so you could make it lighter and take the same number of passengers.

  • It's quite difficult to put just a small amount of value beom into the steel.

  • It's rather like adding just a grain or two of salt to your cooking.

  • So, in fact, the producers of niobium producer material, which is called Farrah niobium, which is a mixture off iron and niobium, of which I've got some pieces here it looks a bit black if you crack it open.

  • And so this is the material that is added to the mix when people are making steel.

  • Well, I believe that some Metella gist in America still call it Columbia MME.

  • On Dhe.

  • I think that's rather nice, but it's not used as the name in chemistry.

  • And in fact, I think most chemists will no longer have even know the name existed.

  • I liked it.

  • It rolls off the tongue so much nicer than some of the modern names for elements that recently discovered ones.

  • But it's also good because it reminds one of the history.

  • And I think the discovery off niobium or Columbia MME.

  • In the sample in the museum is a very good reason why we need to preserve things in museums.

  • Because very often, scientists who come later Candace cover things that the people who originally collected the samples would never have dreamt old.

  • The person who originally collected the sample where no, you been, was discovered, didn't know the elements existed.

  • So there was the sample just waiting for the future scientists to discover this.

  • All right?

  • Yeah.

  • So the other application for NYU you beom is in the alloy with tin, which makes so called superconducting wire some wires when you cool it down to very low temperature, lose all their electrical resistance so you could put through a very big current without heating up, because the heat generated by an electric current is related to the resistance.

  • If the resistance is zero, no heating.

  • This means that you can make very small and very powerful magnets such a used for magnetic resonance imaging on dhe.

  • For some sorts of accelerators, like the Large Hadron Collider at CERN, Niobium again has a really quite important metallurgical role.

  • I'm not a physicist.

  • I'm not sure exactly why it is that niobium tin has thes superconducting properties, but they only happen at very low temperatures.

  • So you need liquid helium to cool them right down before you see this behavior.

element 41 is now you be, um, on dhe I'd ever seen.

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ニオブ - 動画の周期表 (Niobium - Periodic Table of Videos)

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    林宜悉 に公開 2021 年 01 月 14 日
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