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tv   Fit gesund  Deutsche Welle  December 13, 2020 10:30pm-11:01pm CET

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crime fighters are back with africa's most successful radio drama series continues through all of this olds are available on the edge of course you can share and discuss on ws because facebook page going to other social media platforms. to me and know. our planet contains many treasures we extract metals and minerals from the ground to use for building roads machinery and computer chips all our technological progress depends on these resources but supplies of raw materials are not infinite in many cases mining them poisons people and the environment and yet the electronics industry critically relies on them how can we continue to develop technology without draining our world's resources. welcome
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to you tomorrow today the science show on. this gordon moore chemist engineer and entrepreneur back in the 1960 s. he formulated what is becoming known as moore's law roughly speaking does the number of transistors on a micro chip doubles every 2 years back to its computers steadily becoming more powerful more predicted that the trend would continue up to now it has computer chips are getting even smaller team of scientists in germany has now found a way of downsizing microchips still further. it's a simple fact of modern life electronic gadgets get smaller and smaller and they're able to do more and more that microprocessors a constantly becoming by so tiny a small power. but getting computer chips to downsize is not
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a matter of magic it needs the brains of people like being paid to kurtz michelle. and sic a union together as part of an international network they've taken a huge step to even smaller chips. but how computer chips made in the 1st place in principle it takes something like a slight project the chip circuitry is stenciled on to the side but instead of projecting the picture on to a screen you focus it onto a silicon wafer with a light sensitive coating plus. the image can then be developed much like a photograph and at the end you have your computer chips. with technology we can now integrate over 16000000000 transistors onto a microchip that's smaller than a finger chip. but what kind of components do we need for a projector we need
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a light source a and an optical system feet consisting of lenses and mirrors. let's start with a light source light is an electromagnetic wave and waves have a wavelength red light has a known wavelength blue light a short wavelength and ultraviolet light a very short wavelength but what does that have to do with chip manufacture roses mohan property. put simply a long wavelength means large structural size a short wavelength means small structural size. and you are trying to extreme ultraviolet light or you re has a wavelength of 13 member half nominators. that's less than a 10th of the previously large wavelengths. you can create images of structures in much sharper resolution. is. takes
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a laser to generate a u.v. light but how does that work to begin with you have to build the world's most powerful industrial pulsed laser it's a technological masterpiece it produces a high intensity light pain but not even yes. to get that you need to trick a laser beam is aimed at a droplet of liquid tin the high energy light heats that into 220000 degrees celcius transforming it into a plasma which radiates the desired. the pulse laser does that $50000.00 times a 2nd. so that takes care of a we have a light source 'd what's missing is the optical system be. glass lens is a no good for the task they only transmit certain wavelengths and even like not one
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of them. the solution is to use curved mirrors instead of lenses the light only has to reflect on the surface it doesn't have to pass through. the mirror as a ground from glass blocks like this and then polished the surfaces are incredibly smooth. if this marrow was scaled up to be the signs of germany its biggest irregularity would be barely a 10th of a millimeter deep. but it's not just about grinding and polishing a mirror requires a coating. and this equipment gives the merest glass surface extremely thin coatings of silicon and molybdenum. they're only a few atoms thick but the research is apply as many as $100.00 layers why is that. if the mirrors. coating is too thick then it will absorb too much of the light.
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this is but it's still a huge struggle to get good reflection using layers. should. be the maximum reflectivity least 75 percent as far as i know. in practice. reflectivity is a measure of performance and 70 percent is a great value. the magic lies in constructive interference which works like this and. part of this is reflected the rest penetrates the top layer to reach the next more mist reflected the rest penetrates to the next layer and so on if they have the correct thickness the reflected light is. now the light reflected from the. silicon wafer and the next generation computer chip takes.
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this for 20 years it's a great feeling to hold the gadget in your hand with an easy you reach chip inside and to know that we have developed the technology that made this kind of chip possible. the trio of scientists was awarded the christie just german future prize for their innovation that technology is already in use the latest smartphones carry chips fashioned with extreme ultraviolet light it's just one more confirmation of moore's law which says the number of transistors that fit on the chip doubles every 2 years it's. told in the 20 teens people started saying that the limits of moore's law would be reached. and be possible to go any further. with. technology we now have the
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technology with which we can continue pushing moore's law over the next 10 years. telling. one valuable commodity used in modern electronics is gold it's a highly efficient conductor that doesn't rust and hardly reacts that all other elements. in estimated 200000 tons of gold have been mined to date. the search for gold has led to bloody conflicts in many regions and the processes involved in extracting it pollute water and soil and endangered people's health reason enough to come up with alternative ways of striking gold. there's hidden treasure in this trash. germany alone generates a 1000000 tonnes of electronic waste every year and the scrap is
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a gold mine literally just look at this computer circuit board for example. gold conducts electricity better than copper take this gold plated edge connector the gold is used to ensure the best possible connection for high quality fast data transfer. these connectors have to be technically sound meaning the gold plating prevents oxidize ation and guarantees the best possible connectivity throughout the devices lifetime so i thought i know best movement here connectivity be it laptop or smartphone most electronic book which would be function without gold. the electronic waste from 5 computers contains a total of one cram of gold that's actually a lot it's the same as the amount contained in 2 tonnes of. but mining it would
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generate huge amounts of c o 2 anough to drive a car 3 times around the globe. the greater the ecological footprint of a material or product becomes the more important it is to recycle but does recycling make economic sense and doesn't. we protect the environment our group uses a company that recycles medals including goals. the 1st stage involves shredding the waste in separating plastics from metals that believes a mixture of metals which are melted down together in a furnace at $1300.00 degrees celcius the heavier metals gold silver and copper zinc together to the bottom of the melting vessel and can be poured off separately from them by their metals above. the heavy metals end up in plates like these they're mostly copper but they do contain quite a bit of gold. going on 4 stents wife 2
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of these plates weight just under $800.00 kilos has one troy ounce of gold distributed throughout those plates $31.00 grounds our aim is to extract it with a minimum of loss so exciting that beached ranch in process uses a lot of chemicals the plates are dipped in a sequence of acid baths each of which dissolves a different metal from the mixture 1st the copper then silver last of all the goals . are rupees won't let us film the last stage of the process that's a commercial secret. recovers 18 tons of gold to here from electronic waste it's evidently a lucrative business but it's impact on the environment just less beneficial the assets have to be disposed of in an elaborate process and the smelting furnace
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churns out large amounts of c o 2. but recycling gold might soon become more environmentally friendly industrial biotech company brain is working on a completely new method it's using bacteria to recover the gold from the electronic scrap even though by. tyria normally avoid the precious metal like the plague. it emits highly think even though the metal is a not very reactive and that anti microbial so it's a very special property if an organism can survive in high concentrations of the metal quite apart from being able to get the metal into solution esther got bore and her team experimented with thousands of bacterial strains till they found a suitable candidate they've dubbed it pseudomonas mittal solvents meaning metal solving pseudomonas bacterium. the researchers at brain demonstrate how the gold is extracted in a plant they've developed and dubbed the bio extractor. the biological
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miracle takes place in this fact. first polarized electronic waste this black sludge is mixed with a lot of water then the mixture is are nucky lated with the bacteria which are suspended in a yellow liquid. thanks to nutrients in the water the bacteria thrive and we can colonizing the electronic waste particles and leeching the precious metal into solution. the gold rich water is then simply pumped off. but how do you get the gold out of the water. that's the job of a 2nd type of bacteria in these pellets they soak up the cold like a sponge. with
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the pellets or them burned off that leaves a residue of small but very pure gold nuggets. it would psystar the process takes place and a very gentle we work at room temperature the bacteria become active at $26.00 degrees celsius the biological process releases half the amount of c o 2 compared with the melting process the bacterial approach is safer and more eco friendly than the smelting and chemical processes the next stage is to scale up brains brainy solution it may look very promising but it's too soon to say whether the bio extraction methods will win out. to mine gold or other precious metals you usually have to blast your way through masses of rock. but how
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did these raw materials get there in the 1st place many came from hot fluids flowing through cracks in the earth's crust these deposits got pushed up with other layers of rock to form impressive structures if you were from chechnya wanted to know more. the rocks grow. poppy crops like these consist of hard compacts often in brazil formations they're considered immovable and immutable like the old saying solid as a rule. but snow and ice wind and rain gradually wear away the rocky peak of a mountain. it gets ground to pebbles then sound and finally to celt the process of erosion the souces carried away by water and often ends up in the ocean as sediment on the seabed. over millions of years the must become stents and cement into sedimentary rock. where 2 or more of tectonic plates are pushed together the
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sedimentary rock on the edges of the plates pushed upwards to form a mountain chain but the rock doesn't grow again mass it nearly all to shake. back at the peak again erosion begins itself to work the geological cycle starts over. rocks to form and grow when for example calcium carbonate precipitates out of the water from a spring like this one in southern germany. this forms limestone deposits which together with moss and blew out create a firm crust that is impermeable to water. thus the rock does grow a few millimeters a year thanks to the calcium carbonate. the same process can be seen in caves. the water borne deposits form stomach types which grow downwards from the roof and stomach might switch grown up words.
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the right crystal or quartz found in the alps can also grow in a similar way as does limescale in the shower. and even the tartar on our teeth. it's formed by the mineralisation of dead bacteria and dental plaque. the oldest known rocks on our planet are located in canada the cast a nice complex is more than 4000000000 years old a look back into our planet's prehistory the outcrop was formed what it was all. for 900 degrees celsius. the earth was pretty wild back then a multi planet bombarded by meteorites the salt that we now use to season our food was also formed back then. 4 and a half 1000000000 years ago our planet was
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a red hot mass as it cooled volcanoes hold matter from its in a most court to the surface liquid rock richen sodium gushed from fishes in the earth's crust and the gas clouds from the volcanic craters contains not only water vapor but flowing. it remained in the atmosphere until the air cooled enough for the 1st rains. the chlorine was washed down with the rain into the rivers as the water flowed from there into the sea it passed over volcanic rock containing sodium. the water leached out the sodium meaning the primordial ocean now contained but sodium and chlorine. as the sea evaporated in many areas over the course of millions of years it left behind sodium chloride otherwise known as cells. and the process continues to this
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day the sun evaporates the water and sea salt is left behind and on very hot sunny days with steady winds were to kill a fine crystals form the coveted for the just said. today's salt from ancient oceans is also found far from the say the movement of the earth's tectonic plates pushed the salt i the to high at elevations. bone deep into the ground. so all. our salt originally hails from the seas and oceans one of the oldest ways of harvesting this vital material is by allowing sea water to evaporate in basins salt crystals are left behind. but much of the salt formed millions of years ago now slumbers beneath the earth's surface we visit our walk
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salt mine in western germany to see how it is extracted. and that will need about 100 seconds to get to the bottom we're moving at 10 meters per 2nd. move of left amman heads the salt production here 900 meters below ground today they want to extract 8000 tons of salt from the mine and that calls for some unusual measures. if we're going to blast chamber $9101.00 of our biggest a bit specials let's see how it goes. checking in and out is especially important when blast work is being carried out underground. first the work has to be planned this is chamber 910 blasting here requires an entire team.
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but they'll also need to work at 2 other locations in the mine to reach the day's target of 8000 times. the mine is a vast labyrinth of tunnels and chambers 900 meters underground each day it expands a little further. before blasting can proceed in chamber 910 more work is needed elsewhere where the team won't meet its target. let a man doesn't need a g.p.s. to navigate down here i know i've been doing this for 32 years i'm in my element down here in the salt we're nearly there like there's the load at. the wheel loader can pick up 20 tons of salt at a time it's so pure you could sprinkle it straight onto a boiled egg and eat it. as soon as the salt has been loaded up the roof of the chamber needs to be secured. first any loose rocks are scraped off the surface.
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supporting anchors up to 3 and a half meters long are driven into the roof to prevent collapse. conditions are tough it's a stifling 40 degree celsius and the salt makes the air dusty and dry. at least that also means that nothing down here rests. just one hour to go to detonation. if you how's it looking. good we are on schedule but we need to get over to chamber 910 to prepare for blasting. the tunnels and chambers here in the salt mine are usually 7 meters high. but this is the one big exception. chamber 910 is 20 meters high. they're going to blast this ridge
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holes have already been drilled for the explosives. it's the moment of truth the explosives team moves into position. they normally blow up smaller walls . for this one they need half a ton of explosives. first detonators are placed in the drilled holes then explosives are inserted deep into the wall. the detonator wires are magnetic so they're fragments can be retrieved from the salt afterwards. then it's time to move to a safe distance 3 kilometers away. all the leads come together at this central ignition point now they just need the final go ahead. you go hello yeager here is everything clear. ok we'll get
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started. ohms reading good let's go. then. wonderful that was very good. we drive back to the blast site. now needs to check the loose material that's been created by the explosions oh that looks good. so he's happy yeah that's a feat yes very happy it worked beautifully the size and shape of the boulders is
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ideal a very good result. to feed in. and we're the 1st humans to ever hold the solid rock in our hands it's 250000000 years old there you go a gift for you thank you. and if you know how some of us here are your lives is 1500 pounds well yes that's what we needed to reach our goal of 8000 tons for today i'm a very happy go to for. help what is right why are great but i'm a few pages. if you have a science question that's bothering you send it in as a video text or voicemail if we answer it on the show you'll get a little surprise as a thank you just asked we look forward to hearing from you. for more science stories check out our website e.w.
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dot com slash science or look for us on twitter and. that's all for now from tomorrow today your science program m d w thanks for joining us we'll be back next week until then stay healthy and stay curious.
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250 years of look like beethoven a major anniversary. our last look at shooting it travels to vienna he lived here for over 3 decades and wrote his masterpieces and then gone he discovers crops that find history. of a lot of questions that need answering following the footsteps of the great before checking him. coming up on d w. 250
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year old global music star beethoven. in his anniversary year he remains a powerful name on everyone's lips and last. seen guys are 5 conspires traveling projects to this day marks 21. 30 minutes monte w o. 2 children to come tonight it's. one giant problem and when you're in it in no mood to see the 1st year you. denied the lead of the change in the late john the bass how will climate change affect us and our children laugh.
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at e.w. dot com slash water. in the far north. beyond the inhabitable world. it's lonely. barren. and breathtakingly beautiful the arctic a powerful expanse of bitter cold. and the sound of global warming. to the journey around the north pole. profiteers and talk with people experiencing a changing environment for the ice disappears earlier and it keeps retreating decay shirish the last years have been smoldering roughly. measured hard wish to shift.
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our future depends on what happens here in one of the most fragile ecosystems on earth. northern lights life within the arctic circle starts december 21st on w. . this is the w. news and these are our top stories germany will enter a tougher coronavirus lockdown starting on wednesday with schools and non-essential stores is set to close this comes amid a surge in deaths and recent weeks have i got an eyeful appeal to germans to limit their social contacts in the run up to christmas. the united states has begun distributing millions of doses of coups in 1000 facts seen inoculation of health care workers.

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