It’s here: Scientists have reported the discovery of the first room-temperature superconductor, after more than a century of waiting. The compound conducts electricity without resistance up to 15° C, but only under high pressure.
The discovery evokes daydreams of futuristic technologies that could reshape electronics and transportation. Superconductors transmit electricity without resistance, allowing current to flow without any energy loss. But all superconductors previously discovered must be cooled, many of them to very low temperatures, making them impractical for most uses.
Now, scientists have found the first superconductor that operates at room temperature — at least given a fairly chilly room. The material is superconducting below temperatures of about 15° Celsius, physicist Ranga Dias of the University of Rochester in New York and colleagues report October 14 in Nature. However, the new material’s superconducting superpowers appear only at extremely high pressures, limiting its practical usefulness.
Dias and colleagues formed the superconductor by squeezing carbon, hydrogen and sulfur between the tips of two diamonds and hitting the material with laser light to induce chemical reactions. At a pressure about 2.6 million times that of Earth’s atmosphere, and temperatures below about 15° C, the electrical resistance vanished.
Superconductors and magnetic fields are known to clash — strong magnetic fields inhibit superconductivity. Sure enough, when the material was placed in a magnetic field, lower temperatures were needed to make it superconducting. The team also applied an oscillating magnetic field to the material, and showed that, when the material became a superconductor, it expelled that magnetic field from its interior, another sign of superconductivity.
The scientists were not able to determine the exact composition of the material or how its atoms are arranged, making it difficult to explain how it can be superconducting at such relatively high temperatures. Future work will focus on describing the material more completely, Dias says.
When superconductivity was discovered in 1911, it was found only at temperatures close to absolute zero (−273.15° C). But since then, researchers have steadily uncovered materials that super conduct at higher temperatures. In recent years, scientists have accelerated that progress by focusing on hydrogen-rich materials at high pressure.
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This post is to celebrate a moment in time from 1994 when Gloucester Youth Orchestra played at Cheltenham Town Hall. On this occasion a recording was taken on DAT tape and some copies made for the players to listen to their own music.
Having had this tape cassette in my car for the past 10 years or so I decided to digitise the whole concert so it was preserved for the rest of time on youtube.
I have not altered the recording or cleaned up any noise so please realise this is not a perfect recording but simply a memory to share with any of the other players at GLO at that time, and also for future musicians to be inspired.
I have included an image of the full orchestra compliment which also included some guest players on the day.
It is also interesting to see that many of the orchestra have carried on their musical careers after the orchestra. To name but a few…
Charles Peebles who has gone on to conduct many other orchestras in the past few years.
Matthew Elston who now plays as Principal 2nd violin of the BBC Concert Orchestra and teaches music
Diggory Seacome – musical director – went on to become a Conservative Councillor!
Sky lights up over Sicily as Mount Etna’s Voragine crater erupts
Display of volcanic lightning inside giant smoke and ash cloud over Europe’s tallest active volcano is Voragine crater’s first eruption in two years. The night sky lights up over the east coast of Sicily as Mount Etna’s Voragine crater erupts for the first time in two years. The giant plume of smoke and ash thrown up by the blast creates a dazzling display of volcanic lightning, a mysterious phenomenon seen in many of the most powerful volcanic eruptions.
It is thought that ash particles rubbing together inside the cloud could lead to the buildup of an electric charge that triggers the lightning strikes, much as a weak charge builds up on a balloon rubbed on a jumper
When the Icelandic volcano Eyjafjallajökull erupted in 2010, the combination of dust with ice and water from an overlying glacier produced a spectacular “dirty thunderstorm” that sent streaks of lightning leaping around inside the plume that drifted overhead.
The tallest active volcano in Europe, Mount Etna stands 3329m high and has been erupting for an estimated 2.5m years. In modern times, towns and villages in the foothills of Etna have been protected by ditches and concrete dams that divert lava flows to safer ground. The volcano has five craters: the Bocca Nuova, the north-east crater, two in the south-east crater complex and the Voragine. The Voragine crater formed inside the volcano’s central crater in 1945.
Volcanic activity in the region is driven by the collision of the African tectonic plate with the Eurasian plate. Magma from molten rock erupts as lava and ash and builds the volcano in the process.
In a cramped laboratory on the campus of the University of California San Diego (UCSD), graduate student Lizzie Caldwell is hard at work, painting tiny squares of metal with a fine mist of black paint.
As experiments go, it doesn’t look terribly impressive.
Yet the paint she is using is highly sophisticated – the result of intensive research. It is also probably one of the blackest materials ever created.
What the research team at UCSD are trying to do is make large-scale solar power generation more viable, by creating a material which can absorb a greater quantity of sunlight than existing coatings, and last longer.
Heart of darkness
The paint is being developed for a new generation of so-called concentrating solar power plants (CSP).
These use thousands of mirrors to focus sunlight on a central tower, which is coated with a dark, light-absorbing material. The light is converted into intense heat, which is used to make steam. The steam can then be used to drive turbines, in order to produce electricity.
It is a very clean form of power generation, and existing plants which use coal or other fossil fuels can be converted to use the technology. In addition, heat can be stored so that power generation can continue even when the sun isn’t shining.
However, there’s a catch. The light-absorbing coatings which are currently used aren’t really up to the job.
They aren’t efficient enough, can’t withstand the highest temperatures and, out in the elements, bombarded with intense sunlight, they don’t last very long either.
According to Professor Renkun Chen, who is helping to lead the research, the new material will be very different.
“First of all, it can absorb the light at a very high efficiency. And secondly, it can withstand very high temperatures in air, above 700 degrees Celsius. That isn’t possible with existing materials”, he says.
The secret of the new paint lies in nanotechnology – creating a surface made up of layers of microscopic particles. It is designed to minimise reflection.
The research team claims that it can convert up to 90% of the sunlight it captures into heat.
“The size of these particles matches the wavelengths of light, which is in the order of a few nanometres”, Prof Chen says.
“So when light gets in, it will get trapped. It’s as though it gets lost in a miniature forest, and never comes out”.
That is the theory, at any rate. But the mosaic of small metal tiles lined up in the lab for testing is testament to how challenging it is to put that theory into practice.
Each one represents a slightly different technique or chemical formula, as the team searches for the right balance of light absorption and durability.
Fifty shades of black, if you like.
“Right now we’re just playing with a lot of different ideas that we’ve been talking about for the last few months and years” says Lizzie Caldwell.
“We want to make sure we get the perfect, blackest colour”.
Run for the sun
The research has been funded by the US government’s SunShot initiative, which hopes to make solar energy as financially competitive as other forms of power generation by the end of the decade.
It isn’t just happening in the United States. In China, generous subsidies have led to a very rapid growth of solar power generation over the past few years.
This has come partly in response to the country’s voracious appetite for power and the need to curb severe urban pollution. But China has also become a major exporter of cheap solar technology, which has brought prices down worldwide.
And according to Professor Chen, CSP in particular has the potential to become a major source of clean energy in developing countries, reducing their reliance on burning fossil fuels such as coal.
Renowned environmentalist Denis Hayes, who now leads the Seattle-based Bullitt Foundation, thinks that we could be heading for a golden age of solar power.
“With solar, if you take a unit of area, there’s only so much sun that is going to strike it,” he says.
“So if you can get twice as much electricity out of that sunshine, and it costs no more or even less than before then suddenly you’ve transformed the market”.
He thinks that one day, entire cities could be powered by the energy of the sun, with the fabric of the buildings themselves being used to trap solar energy.
It’s fair to say that such a sunny utopia remains a very long way off. However, research such as that being carried out at UCSD just might bring it a little bit closer.
So if there is a golden age approaching, it may owe a debt to some very, very black paint.