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tv   Tomorrow Today  Deutsche Welle  May 31, 2020 11:30pm-12:01am CEST

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in the art of country and. africa. what's in store. to be used for the future in the book. you can't forget major cities to the multimedia inside could conjure up. global energy consumption rises every year many people's biological rhythms are no longer in sync with day and night but more with artificial light what does that mean for us energy demands also to keep eating natural resources renewable energies could help more if they were more efficient one idea is to use lenses to focus on light more precisely on the surface cells in the panel. welcome to tomorrow today the science show on the g.w. . lab.
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stuff how do solar cells actually was so hisself are mainly composed of silicone. silicon asms have full electrons in the outer shell and are stable but then the silicon is split into 2 layers. bosphorus is mixed into one like it has value electrons in its outer shell one too many which can orbit for. the 2nd layer is mixed with boron which has only 3 out electrons one to feel. that means the layer has gaps which attract the excess phosphorus electrons this creates a flow of negatively charged electrons from one layer to the other one layer loses electrons and becomes positive the other gains electrons and becomes negative creating 2 holes eventually all the gaps on the surface of the lay. is occupied the
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holes and the electrons are now too far apart to migrate them with the sun comes in when some light hits the surface like energy splits off one electron making a hole under so close election. the electron is attracted to the positive and the hole goes another electron from another down to replace the one longs which in turn is split off and so i want. the electrons which have the right at the positive pole return by wire to the negative call that's an electric car. and it flows as long as the sun shines. if solar energy is to enable commercial aviation and satisfy our electricity needs in the future then there's still a lot of work to be done. research is forging ahead. florian galusha's come up with
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a new method of extracting even more power from sunlight. what we've done instead of using normal silicon solar cells which have a maximum laboratory efficiency of 26 to 27 percent is to use somewhat more exotic cells their maximum level fission see is over 47 percent but they're expensive and above his expensive solar super cells yellowish months a panel of lenses each of which focuses sunlight on an individual cell throughout the day that boosts efficiency to 29 percent in real life conditions. the main challenge is making sure the light actually hits the cell if it doesn't and it won't produce any energy at all. and drop them in it you know. in gaelic celebratory we get an idea of how it works he uses a model to show how the lenses function each lens in the top panel focuses the sunlight on an exactly defined ray. covering
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a super cell. because those cells are tiny barely one millimeter across. and we use about $10000.00 cells per square meter and each has to have a high degree of tolerance. but now it's time for the engineers to put the lab behind them. right now we're still almost sticking everything together by hand but now the important step is going from the lab to mass production how can i produce a module every couple of minutes using machinery that's the really huge leap we're about to take that will fit in the of mafia. the european union is giving insulate almost 3000000 euros from its advent solar cell fund expensive science but worth it means including insulation our cells are about 20 percent more expensive but they produce 50 percent more energy to. improve his ation of solar energy is one thing
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but it's also highly dependent on the weather it only makes sense when electricity storage facilities have been improved. lithium ion batteries are the standard today but scientists at switzerland's materials testing and research institute show us how dangerous they can be if the lithium ion cells insulation is compromised and the terminals come into contact with metallic objects such as coins the result can be disastrous. our approach to stabilizing the electrolytes involves a highly concentrated salt solution. the swiss researchers have developed a highly soluble salt that only meets a few drops of water here seen in fast motion to function as
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a more conductive but much safer electrolyte in lithium ion batteries. that kind of storage battery would be enormously useful for storing solar energy in people cellars or in other very large batteries. to bridge the nighttime gap as well as bad weather. batteries are the ideal solution for delaying energy consumption for a few minutes or even day and. solar energy for 40 days or the night time in future we could be storing it in less volatile batteries and we have today. it's energy that could become abundantly available thanks to a new generation of panels to collect it. ideally we wouldn't use any energy at all that's the idea behind the ancient dream the cultural motion machine that moves without any energy source but the laws of
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physics teach us that it's not possible i can't eat everything up to hope that the bullet itself. if i lose and i have to replace it on the other hand. without it. might just one. phoenix looks like. but it's actually an airplane or to be precise and unmanned aerial vehicle. it's to . the prototype the wings and tail will be added shortly we joined the team amid preparations for the 1st test flight. the researchers have chosen a huge building for their 1st attempt to get phoenix into the air a tense moment for its inventors. scientists from various universities and companies in britain spent 3 years working on phoenix. aerodynamics professor andrew rein and set the teen years. says.
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the goal was to build an aircraft that could propel itself without the need for an engine. has been around for a long time over 150 years and it's used underwater for remotely operated vehicles so there are various things are used underwater for surviving but nobody's made it work in air before because there is a sound sometimes less dense in water the physical process is more complicated phoenix is filled with helium the material for the outer hull had to be developed specially it needed to be lightweight but dense enough to prevent the tiny helium molecules from seeping through. the wings are made of lightweight carbon fiber both the wings and tail carry solar panels to provide the plane with power some is stored in batteries meaning phoenix can also fly at night. this is phoenix in its
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fully assembled stage the aircraft will likely be used as an atmospheric satellite or pseudo satellite either for telecommunications or for things like land surveillance after natural disasters to see where help is most needed one of the possibilities is as a suit our satellites are being able to do surveillance and monitoring and it would fly at 20000 meters and 20000 meters because that's where the weather is is most benign. winds are much lower than they are on the surface phoenix is 15 meters long and weighs just $120.00 kilos without the helium. that means it requires very little power. its huge advantage is that because it has no engine it doesn't need to carry any fuel that means it can remain airborne for weeks or months at a time. the mix is also relatively cheap to manufacture. it's propelled by what's
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known as variable buoyancy propulsion this is how it works. and is lighter than air and therefore pulls the aircraft up towards the underside is equipped with 2 compressors which draw in air from outside and compress it filling a bag inside the aircraft. that makes the plane heavier causing it to sink again. the air is then pumped out making the aircraft lighter and causing it to rise again this ability to believe as it were moving up and down combines with the lift generated on its wings to move it forward. half the time phoenix is heavier than air like an airplane. the other half it's the lighter than air like a balloon. the model has been through countless tests in wind tunnels.
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andrew ray is responsible for the aerodynamics and element he's keen to improve further tests. using lasers and smoke his team is able to show how the air flows around the model. they needed to establish the most efficient design to allow the aircraft to maximize the use of its kinetic energy. the. after 3 years of development the prototype was ready for its 1st test flight. and it was a success phoenix flew in waves down the 120 metre long hangar exactly as it was designed to do.
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we were all pleasantly surprised that it worked as well as it did. we initially had hoped to. do one series of tests where was like the narran one had to navigate through so well to begin with that we were able to do multiple transitions between the 2 when it flew forward repeatedly during the flights are still. work is now underway to build the next prototype it's said to be 4 times as enormous phoenix and capable of flying at the target altitude of 20000 meters. the earth by night have it by in a right of tiny luminous dots it could be beautiful in another context electric light does make modern life possible independent from the 24 hour day might rhythm would have freedom but also what a catastrophe it confuses the environment and least spend too much time in an artificial light and not enough of an essential sunlight time for an experiment.
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these 3 people are exposed to different levels of light during their day. boss john works in an office which means spending long hours in artificial light. thomas is a goat herd and is mostly outdoors. then there is not. a doctor who works as a surgeon in a hospital and she works at night when her body is telling her it's dark and time to go to bed. we equip our test subjects with a special device that measures the brightness and composition of the light they're exposed to. and then we track them around the clock for a week. we want to know how much and what type of light our test subjects are
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exposed to and when. sleep researcher alfred and light expert. analyze the results. what will they show how much like to our subjects receive at what time of day. tomas the go to earth tends to be out in the open with natural like the lord even in gloomy weather he's subject to several 1000 locks per day. after sundown he manages without a television or mobile phone which both emit a lot of blue light and are disruptive. this shows the amount of natural light thomas is exposed to over the course of several days in the. mall going on the meter side there's a very high a luminance in the morning and around noon up to $7000.00 lux dollars and looks on
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and on and in the afternoon it drops significantly. around $100.00 lux or lowered looks on immediately. and at night the light exposure is reduced to an absolute minimum of absolute minimum they don't see it in accordance with their natural day genetic rhythm effects the stock knocked over at most and pushed. us john's case the details place almost exclusively indoors despite having large windows he always turns on the light but artificial light is usually very weak whereas goatherder traumas can reach 7000 lux bus john's level is just 220 bus gen so spends most of his evenings in front of a t.v. or computer screen in addition to being low light they emit primarily blue light this lowers the wake sleep regulating hormone melatonin and reverses his inner rhythm essentially turning back his biological clock and the result for us john is
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this modest hour by hour exposure to light on a typical working day then just cut him while working in the office we have 2 $100.00 to $220.00 blocks which is far short of daylight bite and found fun that. what we notice is that he still has a relatively high illuminance after work until he goes to bed. who are. at this so and that he definitely has a negative effect on his sleep wake behavior. and you got the 5. now dean is a doctor who likewise works with a little light most of it artificial. and sometimes with practically none. under come i'm just arrived for a night shift saturday night which no one likes to see but i'm not properly rested even after. commission. but she needs to be wide awake
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not least when stitching up the wound at 1 am. the surgery room light is particularly strong which helps right now but for her biological clock it's unnatural outside of course it's dark. if she's lucky and it's a quiet night nadine will be able to take a break and catch up on her sleep. but it's only a matter of time until she's called to the next patient which means getting up again pronto. the rude enough to 50 even so my night shift is over and my colleague is now taking over for the daytime shift as a bitch to try i'm cafe but you can't really look forward to going home when you know you'll be back again this evening mind with. and this is what her light exposure chart looks like. in. common for the 1st
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3 days you can see a relatively good day night rhythm after that her night shifts begin. and then there's no dana rhythm at all as far as light exposure is concerned the least exposed it's. there and she's more or less exposed to continuous lighting. and that constant light is anything but natural. her biological clock has no means of orientation. in order to reset her clock back to normal she needs daylight in the morning between 8 and noon a time of day 3 subjects differ substantially in exposure. the blue line shows the light on a typical morning for office worker boss john read is that of dr 19 and greene heard tomas whose exposure is 10 times higher in those crucial morning hours. so
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how can the office worker and doctor get more. we'll have the solution for you in a moment but 1st of all be honest how much you have to rely on artificial light and if you have strategies for avoiding too much of it. brown says they don't have too much artificial light in nigeria so they don't really depend on it. and rising from colombia most had tells us it really makes a set that light pollution means she can see the greatest show on earth the milky way it's like a cascade of diamonds sparkling in the sky. and fucker tells us that pakistan's rural areas have barely any artificial mice at night the people there are healthier than city people they're also very strong emotional they stay calm worry less and mostly smile thanks for writing in.
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even if in some regions night time still looks like night time for the world as a whole has been getting brighter which simply. many professions are rescheduling work to happen over night some only work at night but how can you stay healthy despite that. that daylight experiment. thomas spends most of his days outdoors so he gets plenty of natural light in the evenings he tends to avoid screens their high blue spectrum output he's just fine but boss johns' office job means he has a serious light deficit problem and not just because his office is too dark to wonder stayed in an office worker circadian rhythms are completely disrupted. we should try to adjust his biological clock. so he'll be more capable and alert in
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the morning 514 highest for boss john that means for. 1st thing in the morning it's out into the fresh air and natural light not exactly a grueling task skipping one stop on the subway into work is all it takes. we also install a standard daylight lamp on his desk for him to use during the morning that way he's getting 2000 lux even in the office. and in the evening a book is always better than a screen. measurement show just how even a smartphone can influence our sleep patterns normal display light is dominated by the blue spectrum that suppresses melatonin the hormone that steers our weak sleep rhythm however many smartphones now feature a filter called night shift it cuts down the blue spectrum components sharply. it lets you use your smartphone without feeling guilty about disrupting your sleep
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the stuff they start out. but others do this is the time to see something with the daylight lamp and walking in broad daylight i've got a feeling that i get tired very much earlier at night and want to go to sleep. i'm trying to give it it gets on my nerves a bit because i like to stay up late. so what i don't feel like i'm struggling to get through the day like i used to before this whole experiment how did she just. instead and quite often much more alert. hospital doctor 19 really gets much daylight and her chips go counter to her biological clock adrenaline is what keeps her remarkably awake at work the. future she's doing a lot right now she's limited by her night shifts of course what is important is that she at least grabs whatever sleep she can when on shift. the sleep experts
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offer her another suggestion after a night shift should try specially colored glasses which filter out light that studies are melatonin level and she'll sleep easier when she gets home the experiments outcome is that the most important thing is to get a lot of natural daylight preferably in the morning that way the biological clock settles into its natural rhythm and also to try to go without screens in the evening and if night ships are a must then only a few of them at a time grouped together a well maintained biological clock never needs reminding. so some line says that much we know it also helps us to produce this mental. development and also said to boost the immune system but getting the right amount of sunlight as opposed to much. he says and healthy the world long ago adopted to the sun's 24
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hour over them it's regulated human life for thousands of years but how did it come the balance amos from zambia wanted to know. how was the sun created. it's been burning away for over 4 and a half 1000000000 years and is not even halfway through its projected lifespan. one in which human history is just the blink of an eye. but while we may be just a transitory moment in cosmic terms we are at least able to study the life cycle of the sun. all galaxy is home to billions of other stars like it. space telescopes have given astronomers a closer look at how stars evolve. our own son was born from
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a cloud of gas and dust over the course of millions of years. it's a magical process reproduced here on a computer. this cloud of dust contains regions of denser gas like pearls on a necklace. the astral embryos that emerge there continue growing until they have sufficient mass to ignite the sun's fire. if outlet is right why up in latin. do you have a science question that you've always wanted on state we have you to help out send it to us as a video text ovoid smell if we answer it on the show we'll send you a little surprise as a thank you can i just ask. if you like to see one. sign stories then visit our web sites or follow us on twitter or facebook.
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that's all from tomorrow and today for this week the next time looking at the power of thought we'll be able to operate machines just by thinking the 1st models are already being tested more on that next week to see them.
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tracing the border one step by germany. today i want to take you on the road tore along the border of ukraine has there and the ratio of over 30 years ago i am cuts and divided the world into east and west right here to find out what has changed the century unification and we'll explore what from aims for this it is to see today. changes. coming.
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in fantasy and the french. readers the world over i don't lead to value or how much . need the artists to be caught up with the creator of fantastical worlds to an exclusive interview. misfunction. do you do an. arts. 21. 30 minutes on d w. i'm neal come to. the 2nd season of on the fence it's about the environment of sue about society and it's still about us with all the planets on the brain responsible leading experts in the field. look up just
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a couple who says. when the water rises cities will sink into the sea. entire stretches of land will be abandoned. when the water dries. up to stop its happening faster than anticipated. massive sprinklers are supposed to prevent flooding but they only delay the inevitable. how will we live in the future. 66 me as a sea levels starts june 5th on d w. sound. to assume. then beethoven's pastoral symphony is the foundation
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of an international art project. to mark the 250th anniversary of the composer's 1st beethoven world wide. street project starts june 4th on t.w. . this is news and these are our top stories. the united states is braced for more on the wrist as protest broke many areas of the death of a black man in police custody in minneapolis curfews are in force in several big cities including los angeles philadelphia and atlanta. but the space x. dragon capsule carrying 2 nasa astronauts has docked with the international space station the craft completed the 900 allergenic it's the.

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