Placeholder Image

字幕表 動画を再生する

  • So now I'm going to show you Raman's collection of minerals

  • Lots of people had collections of minerals but his is special because he collected them all personally

  • And so ... brought them back here

  • So there is his own character, if you like, in his choice of things that he collected

  • Let's go and see some of them

  • There's a bewildering number of things to see

  • And one of the first things which is really very special is over here

  • When Raman first moved into this institute, there was no electricity

  • So he had this special device to reflect the Sun off this mirror into the room

  • As you know the Sun moves around as the time of day

  • But there's a special clock here and a system of levers

  • so that as the Sun moves, the mirror moves to keep the sun shining into the room

  • So let's go look at some of the samples

  • I'll just show you a few ... whichever ones look really interesting

  • So he looks really wise

  • These are interesting pearls which come from oysters as you know

  • Raman was very interested in the scattering of light

  • And the silvery color of pearls is due to the scattering of light between the layers of calcium carbonate that's laid down in the pearl

  • Here there are all sorts of gemstones

  • and, Jade from China, samples from Brazil

  • He traveled all over the world

  • Quartz, silicon dioxide (SiO2), which contains inside it some liquid that was trapped during the geological process

  • Using light, which can shine through this he could find out what the liquid was without damaging the crystal

  • and he showed that the liquid was water with a mixture of carbon dioxide and methane

  • So, if you think about it it's really quite clever

  • Without damaging the crystal, you can find out what's inside

  • There's a really nice story about this piece of quartz

  • He got it from a farmer who brought it to sell it to him

  • And he bought it and then discovered about the liquid afterwards

  • Otherwise, the farmer would've probably ask for a lot more money

  • Here there are opals

  • Again the color is due to the scattering of light...

  • ...something that fascinated Raman

  • Over here, there are some things which are very interesting but actually rather ordinary stuff

  • So up here are these really nice crystals

  • And theyre sugar!

  • Normally we see tiny crystals of sugar

  • I've never seen such big crystals of sugar in my life

  • I've got quite small hands but theyre still quite big

  • And even bigger down here are two salt crystals

  • These are natural salt crystals that Raman collected from a salt mine in Poland

  • And up here there are rather nice crystals of copper sulfate

  • Over here we have some nice samples of sulfur

  • I've got a small sample at home but it doesn't look anything as beautiful as this

  • And presumably this came from somewhere volcanic

  • And these samples here have a specially interesting story

  • These are artificial crystals

  • Apparently, there was a power cut - the electricity went off for several days

  • And not far from here there is a steelworks or, there was, where they made steel continuously in very hot furnaces

  • But when the electricity stopped, Raman realized that the furnaces would stop and there might be good crystals there

  • So he rushed off

  • and before they could start up the furnaces again he got these really nice crystals of carborundum

  • So now I want to show you the thing that I find the most moving in the whole of this display

  • Over here are two stones that come from the center of Hiroshima, the city that was attacked with the first-ever atom bomb

  • And these are pieces of mineral that have melted

  • The melting point is about 1800 degrees centigrade

  • And they apparently melted in the center of Hiroshima

  • Raman was given these pieces of stone by the city of Hiroshima in recognition of his active opposition of the use of nuclear weapons

  • But he was quite careful

  • and he said send them to me

  • and he had them tested for radioactivity before he added them to his collection

  • In here, we have series of samples of rock that don't look particularly special

  • but above them are some UV lamps

  • and if we switch out the light with the visible light

  • then suddenly, you see something really quite interesting

  • that all these minerals begin to glow

  • And they glow because they are absorbing UV light and then some of the energy is lost inside the crystal structure and they emit visible light

  • In here's some Ruby

  • and the large lump in the middle is artificial synthetic Ruby and the little bits round about are natural Ruby

  • and you can see that the natural Ruby fluoresces very nicely whereas the artificial stuff doesn't

  • This sample here is interesting ... something I've never seen

  • This rather grey mineral is called crocidolite and it is what asbestos is made from

  • You've probably heard that asbestos fibers - these very fine fibers - that were used for insulation can be breathed in and cause cancer

  • This sample is what asbestos is made from

  • And because it's dangerous, I'm not going to pick it up

  • Just as we were going, Shashi, who is the curator of this museum, produced another treasure for us

  • These are natural diamonds for optical windows which give you very strong windows that you can use for high pressure vessels and so on

  • And look at the size ... it's amazing!

  • I've seen diamond windows before but never seen natural ones of this size

  • These are natural diamonds which have been chopped to give you a slice of this

  • So the actual diamond itself must have been very much bigger

  • and diamonds of that size are extremely valuable

  • [Raman’s Nobel Prize] So this is the citation and here, as you can perhaps guess, is the medal

  • [Raman’s Spectroscope] Whenever he saw something interesting - a flower, a rock, whatever, he could look through this and see the spectrum

  • [Objectivity] Hello everyone! Welcome back to objectivity!

  • [Objectivity] Of course I'm wearing gloves

  • [Objectivity] But you know we mean business today because Keith is wearing gloves!

  • [Objectivity] Wow!

So now I'm going to show you Raman's collection of minerals

字幕と単語

動画の操作 ここで「動画」の調整と「字幕」の表示を設定することができます

B1 中級

ダイヤモンド、真珠、原爆石 - 動画の周期律表 (Diamonds, Pearls and Atomic Bomb Stones - Periodic Table of Videos)

  • 2 0
    林宜悉 に公開 2021 年 01 月 14 日
動画の中の単語