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The
Graphene story Scientists wiring
oceans to protect ecosystems
This
Universe |
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The Graphene story THE creation of graphene, a wonder material that promises to transform the future, is already the stuff of scientific legend. As a piece of brilliant serendipity, it stands alongside the accidental discovery of penicillin by Alexander Fleming — and it might prove just as valuable. Two Russian-emigre scientists at the University of Manchester — Andrei Geim and Kostya Novoselov — were playing about with flakes of carbon graphite in an attempt to investigate its electrical properties, when they decided to see if they could make thinner flakes with the help of sticky Scotch tape. They used the tape to peel off a layer of graphite from its block and then repeatedly peeled off further layers from the original cleaved flake until they managed to get down to flakes that were only a few atoms thick. They soon realised that by repeatedly sticking and peeling back the Scotch tape, they could get down to the thinnest of all possible layers, one atom thick — a material with unique and immensely interesting properties. When the two scientists won their joint Nobel Prize in Physics in 2010 for their ground-breaking experiments, the Nobel committee made a point of citing the “playfulness” that was one of the hallmarks of the way they have worked together. Playing about with the Scotch tape on a Friday afternoon sounds a jokey thing to do, but it soon turned into a deadly serious game of scientific discovery which would have been impossible if not for the well-prepared minds of Geim and Novoselov. “A playful idea is perfect to start things but then you need a really good scientific intuition that your playful experiment will lead to something, or it will stay as a joke for ever,” Novoselov says. “Joking for a week or two is the right way to go, but you don’t want to make your whole research into a joke.” Geim, who is 15 years older than Novoselov and was once his PhD supervisor, has a reputation for playful experiments. He levitated a frog in 1997 to showcase his work in magnetism and invented a new kind of sticky tape based on the adhesive feet of Gecko lizards which can walk up walls and hang upside down on ceilings. The original idea of working with graphite was to see if it could be used as a transistor — the fundamental switching device at the heart of computing. In fact, Novoselov says, they had almost given up with graphite when they heard about how microscopy researchers working along the university corridor used Scotch tape to clean the mineral before putting it under the lens. “It was not a new technique, and I’d heard of it before, but when you see it in front of you it makes it obvious what it can be used for,” Novoselov recalls. Graphene, a two-dimensional crystal of pure carbon, is a superlative material. It is the thinnest and strongest substance known to science — about 100 times stronger than steel by weight. A square metre of graphene, a thousand times thinner than paper, made into a hammock would be strong enough to cradle a 4-kg cat, but weigh no more than one of its whiskers. It is a good conductor of electricity, is stretchable and yet is almost transparent. It conducts heat better than any other known substance. It acts as a barrier to the smallest atom of gas — helium — and yet allows water vapour to pass through. This particular property has allowed the two Russians to perform another playful experiment, this time in passive vodka distillation — water evaporates through a graphene membrane placed over a mug of watered-down vodka, leaving the concentrated alcohol behind. The inventive step that made Geim and Novoselov into Nobel laureates was to find a way of transferring the ultra-thin flakes of graphene from Scotch tape to a silicon wafer, the material of microprocessors. Once they did this, the extraordinary electrical properties of graphene could be witnessed and explored, including its “ghostly” quantum state when electrons start to behave weirdly as if these particles have no mass. “The excitement would exist even without these unusual properties because graphene is the first two-dimensional material. It seems obvious now because we can suspend it in the air and do almost anything with it, but at the beginning it was by no means obvious that it would be stable,” Novoselov says. “And then on top of that there are other excitements such as the very unusual electronic properties that we’ve never come across before. Then there are the unusual optical properties, chemical properties and many more. “We have a really unique opportunity here in that quite a few unusual properties are combined in one material; the strongest, the most flexible, the most stretchable, the most conductive, optically transparent and something which is a good gas barrier. So you can invent quite a few new applications that were not possible before,” he adds. The potential uses for graphene appear almost limitless. They range from new types of flexible electronics that could be worn on clothes or folded up into a pocket, to a new generation of very small computers, hyper-efficient solar panels and super-fast mobile phones. Yet at the heart of graphene is a honeycomb structure of carbon atoms — described as “atomic chickenwire”. Carbon is the basic element of life, which means that graphene could be the focus of a new industrial revolution based on electronic components that are biodegradable and sustainable. If there was ever a building material for a new, green economy, graphene could be it. As a result, the government has actively supported a new National Graphene Institute (NGI) in Manchester, which will be completed by 2015 at the cost of £61m, of which £38m is coming from government research councils. The NGI, which will be built on the site of a Victorian gentleman’s club, where Friedrich Engels once sipped aperitifs (presumably after working on the Communist Manifesto), is poised to reap the commercial spin-offs that are likely to tumble out of graphene research. “The model is that we allow our scientists to work on the projects that they want to work on, and we put engineers from companies to work in the same labs,” Novoselov says. “If there is something interesting that the company believes should be pushed forward then there will be collaboration with the scientists to bring it to the next level,” he says. Geim, who declined to be interviewed, is working closely with Novoselov on all aspects of the institute’s architecture as well as the way it will work to encourage both scientific discovery and its commercial exploitation. They both hope to foster an industrial revival to rival the one that began in this part of north-west England 200 years ago —but with carbon in the form of graphene rather than coal. — The Independent
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Scientists wiring oceans to protect ecosystems Scientists
are wiring oceans to track the movements of deep sea creatures that could help protect marine ecosystems by revolutionising how we understand their function, population structure, fisheries management and species’ physiological and evolutionary constraints. Barbara Block, Marine Sciences Professor at the Stanford University’s Woods Institute, is using technology to enable live feeds of animal movements relayed by a series of “ocean WiFi hotspots”. Block is studying pelagic (deep sea) creatures with telemetry tags. The miniaturisation of sensors for tags has vastly expanded researchers’ capacity to obtain data from ocean organisms as tiny as bacteria and as large as blue whales, according to a Stanford statement. — IANS
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This Universe Which
is the strongest theory of the formation of universe other than the
Big Bang? The strongest, meaning the one that will get the most votes, and explains the largest number of observations, is the so-called Big Bang theory. That does not mean that we have finally arrived at the TRUTH. That might be a long way off, perhaps infinitely far. Why are academic studies called ‘research’, not ‘search’? I really do not have a proper answer to your question. I suppose it was invented in relatively modern times, when it became fashionable for many students and their teachers to claim that their studies were meant to create entirely new knowledge, but modesty demanded that their methods of searching were at least different from those that were/are used by many others engaged in similar searches. Hence it was useful to call all ‘search’ as ‘research’. Perhaps this is not universally true. Readers can e-mail questions to Prof Yash Pal at palyash.pal@gmail.com
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Trends CAPE CANAVERAL, Florida: A recovery team funded by Amazon founder Jeff Bezos has plucked two rocket engines from the floor of the Atlantic Ocean that were used to send astronauts to the moon more than 40 years ago, he wrote on the project’s website on Wednesday. Bezos, the chief executive of Amazon, last year announced plans to search the sea floor for rocket motors shed during Saturn 5 launches to the moon during the 1969-1972 Apollo programme.
US restarts plutonium production for space probes CAPE CANAVERAL, Florida: The Department of Energy has produced its first batch of non-weapons grade plutonium, used to power space probes, since a nuclear reactor shutdown 25 years ago, NASA officials said. The US space agency turned to buying radioactive plutonium-238 from Russia after safety issues prompted the Department of Energy to close its Savannah River Site in South Carolina in the late 1980s.
Microbes flourish in deepest spot in world’s oceans OSLO: Microbes are thriving in surprising numbers at the deepest spot in the oceans, the 11,000-metre (36,000 ft) Mariana Trench in the Pacific, despite crushing pressures in sunless waters, scientists said. Dead plants and fish were falling as food for microscopic bugs even to the little-known hadal depths, parts of the seabed deeper than 6,000 meters and named after Hades, the god of the underworld in Greek mythology, they said.
EU could impose pesticide ban to protect bees BRUSSELS: EU governments recently failed to agree on a ban on three widely used pesticides linked to the decline of honeybees, but the European Commission could force one through by the summer unless member states agree on a compromise. A sharp fall in bee populations around the world, partly due to a phenomenon known as colony collapse disorder, has fuelled concerns over the impact of widespread use of pesticides, notably the neonicotinoids class. — Reuters |
Thin
as an atom, with amazing strength and electrical properties, graphene is the
scientific find of the century. But it all came about from mucking about in a
lab in Manchester, one of the men behind its invention reveals
