First superconducting graphene created
Toronto:Physicists have created the first ever superconducting graphene sample by coating it with lithium atoms, an advance that may lead to the development of graphene electronics and nanoscale quantum devices.
Although superconductivity has already been observed in intercalated bulk graphite – three-dimensional crystals layered with alkali metal atoms, based on the graphite used in pencils – inducing superconductivity in single-layer graphene has until now eluded scientists.
“This first experimental realisation of superconductivity in graphene promises to usher us in a new era of graphene electronics and nanoscale quantum devices,” said Andrea Damascelli, director of University of British Columbia’s Quantum Matter Institute.
Graphene, roughly 200 times stronger than steel by weight, is a single layer of carbon atoms arranged in a honeycomb pattern.
Along with studying its extreme physical properties, scientists eventually hope to make very fast transistors, semiconductors, sensors and transparent electrodes using graphene.
“This is an amazing material,” said Bart Ludbrook, a former PhD researcher in Damascelli’s group at UBC. “Decorating monolayer graphene with a layer of lithium atoms enhances the graphene’s electron-phonon coupling to the point where superconductivity can be stabilised,” he said.
The research team, which included colleagues at the Max Planck Institute for Solid State Research through the joint Max-Planck-UBC Centre for Quantum Materials, prepared the Li-decorated graphene in ultra-high vacuum conditions and at ultra-low temperatures.
The research was published in the Proceedings of the National Academy of Sciences. (PTI)
World’s oldest fossil sea turtle discovered
Berlin:Scientists have discovered the world’s oldest fossilised sea turtle, which is almost completely preserved and dates back to about 120 million years, in Colombia.
The skeleton from the Cretaceous period, with a length of nearly 2 metres, shows all of the characteristic traits of modern marine turtles.
“We described a fossil sea turtle from Colombia that is about 25 million years older (than the previously known oldest specimen),” said Edwin Cadena, a scholar of the Alexander von Humboldt foundation at the Senckenberg Research Institute in Germany.
Cadena made the unusual discovery together with his colleague from the US, J Parham of California State University, Fullerton.
“The turtle described by us as Desmatochelys padillai originates from Cretaceous sediments and is at least 120 million years old,” said Cadena.
Sea turtles descended from terrestrial and freshwater turtles that arose approximately 230 million years ago.
During the Cretaceous period, they split into land and sea dwellers. Fossil evidence from this time period is very sparse, however, and the exact time of the split is difficult to verify.
The fossilised turtle shells and bones come from two sites near the community of Villa de Leyva in Colombia. The fossilised remains of the ancient reptiles were discovered and collected by hobby paleontologist Mary Luz Parra and her brothers Juan and Freddy Parra in the year 2007.
Since then, they have been stored in the collections of the Centro de Investigaciones Paleontologicas in Villa Leyva and the University of California Museum of Paleontology. Cadena and Parham examined the almost complete skeleton, four additional skulls and two partially preserved shells, and they placed the fossils in the turtle group Chelonioidea, based on various morphological characteristics. Turtles in this group dwell in tropical and subtropical oceans.
“Based on the animals’ morphology and the sediments they were found in, we are certain that we are indeed dealing with the oldest known fossil sea turtle,” said Cadena. The study was published in the journal PaleoBios. (PTI)
Whisky in space acquired smoky flavours, meaty aroma!
London: A Scottish distillery that sent unmatured malt whisky into space for three years to study the effect of near-zero gravity on flavour has found that the sample had acquired a set of smoky flavours, a meaty aroma, and was “noticeably different” from the one on Earth.
Ardbeg Distillery, on Islay, sent a vial to the International Space Station in a cargo spacecraft in October 2011. Another vial of the same whisky was kept at the distillery for comparison.
The distillery said its space sample was “noticeably different” in terms of aroma and taste.
The Earth sample had a woody aroma, reminiscent of an aged Ardbeg style, with hints of cedar, sweet smoke and aged balsamic vinegar, as well as raisins, treacle toffee, vanilla and burnt oranges.
But the space sample had an intense aroma with hints of antiseptic smoke, rubber and smoked fish, along with a curious, perfumed note, like violet or cassis, and powerful woody tones, leading to a meaty aroma, ‘BBC News’ reported.
On the palate, the Earth sample with its woody, balsamic flavours shone through, along with a distant fruitiness, some charcoal and antiseptic notes, leading to a long, lingering aftertaste, with flavours of gentle smoke, tar and creamy fudge.
The taste of the space sample was very focused, with smoked fruits such as prunes, raisins, sugared plums and cherries, earthy peat smoke, peppermint, aniseed, cinnamon and smoked bacon or hickory-smoked ham.
The aftertaste was intense and long, with hints of wood, antiseptic lozenges and rubbery smoke.
“When I nosed and tasted the space samples, it became clear that much more of Ardbeg’s smoky, phenolic character shone through – to reveal a different set of smoky flavours which I have not encountered here on earth before,” he said. (PTI)
Teenage kids better at taking financial decisions
New York: If you find your teenage kids irrational at times and scold them for making bad real-life decisions, listen to their logic with patience as they may actually be more analytical in their economic choices.
According to researchers from Duke University, adolescents ages 10 to 16 can be more rational than many slightly older young adults.
“The new results point to the idea that we should not think of adolescents as being irrational. What is different about them is they do not use simple rules as effectively,” said Scott Huettel, professor of psychology and neuroscience.
In the new study, participants were presented with three scenarios (A, B, and C) and asked to pick the best one.
Each scenario contained a set of outcomes that could lead to winning or losing different sums of money.
Young adults — who were 22 years old on average — used simple rules.
As they completed more trials, they counted the number of wins and losses in each scenario and picked the one with the most wins, ignoring the dollar amount of each potential gain or loss.
Adolescents, on the other hand, accounted for the magnitude of the potential win or loss and chose scenarios to minimise loss. (IANS)
