Wednesday, December 21, 2011
The Welcome Song
Saturday, November 19, 2011
Lightest Material !
A team of engineers claims to have created the world's lightest material.
The substance is made out of tiny hollow metallic tubes arranged into a micro-lattice - a criss-crossing diagonal pattern with small open spaces between the tubes.
The researchers say the material is 100 times lighter than Styrofoam and has "extraordinarily high energy absorption" properties.
Potential uses include next-generation batteries and shock absorbers.
The research was carried out at the University of California, Irvine, HRL Laboratories and the California Institute of Technology and is published in the latest edition of Science.
"The trick is to fabricate a lattice of interconnected hollow tubes with a wall thickness 1,000 times thinner than a human hair," said lead author Dr Tobias Schaedler.
Low-density
The resulting material has a density of 0.9 milligrams per cubic centimetre.
By comparison the density of silica aerogels - the world's lightest solid materials - is only as low as 1.0mg per cubic cm.
The metallic micro-lattices have the edge because they consist of 99.99% air and of 0.01% solids.
The engineers say the material's strength derives from the ordered nature of its lattice design.
By contrast, other ultralight substances, including aerogels and metallic foams, have random cellular structures. This means they are less stiff, strong, energy absorptive or conductive than the bulk of the raw materials that they are made out of.
William Carter, manager of architected materials at HRL, compared the new material to larger low-density structures.
"Modern buildings, exemplified by the Eiffel Tower or the Golden Gate Bridge are incredibly light and weight-efficient by virtue of their architecture," he said.
"We are revolutionising lightweight materials by bringing this concept to the nano and micro scales."
Robust
To study the strength of the metallic micro-lattices the team compressed them until they were half as thick.
After removing the load the substance recovered 98% of its original height and resumed its original shape.
The first time the stress test was carried out and repeated the material became less stiff and strong, but the team says that further compressions made very little difference.
"Materials actually get stronger as the dimensions are reduced to the nanoscale," said team member Lorenzo Valdevit.
"Combine this with the possibility of tailoring the architecture of the micro-lattice and you have a unique cellular material."
The engineers suggest practical uses for the substance include thermal insulation, battery electrodes and products that need to dampen sound, vibration and shock energy.
Neutrinos beat light yet again!!!
The team which found that neutrinos may travel faster than light has carried out an improved version of their experiment - and confirmed the result. If confirmed by other experiments, the find could undermine one of the basic principles of modern physics.
Nothing's changed about the neutrinos, of course. But the Italian Institute for Nuclear Physics (INFN) researchers who shocked the world in September with a claim that they'd measured particles traveling faster than the speed of light now say a potential flaw in their experiment has been ruled out.
"New tests conducted at the Gran Sasso National Laboratory of INFN by the OPERA Collaboration, with a specially set up neutrino beam from CERN, confirm so far the previous results on the measurement of the neutrino velocity," the INFN team said in a statement released Friday. "The new tests seem to exclude part of potential systematic effects that could have affected the original measurement."
In September, an international team of scientists led by Dr. Sergio Bertolucci reported that particles they had been firing for several years from the CERN particle accelerator in Switzerland at detectors at the OPERA facility in Gran Sasso, Italy located about 450 miles away appeared to be arriving at their destination a fraction of a second earlier than the time it would take light to get there.
The particles, traveling through air, water, and rock, shouldn't have hit the Gran Sasso detectors any sooner than about 2.4 thousandths of a second after being fired, which is the time it would take light to travel the distance between the two points. Yet the CERN researchers reported that their neutrinos were getting to the target 64 nanoseconds faster—meaning that they were traveling faster than light, supposedly impossible according to Albert Einstein's Special Theory of Relativity.
That news sent the scientific community into an uproar, spawned breathless headlines questioning whether E still equaled MC squared, and gave new hope to anyone who has dreamt of faster-than-light travel to distant stars and planets.
The report also kick-started a movement to show that the results were somehow flawed—in short, science started doing what it's supposed to do when surprising and potentially groundbreaking results are published.
Among the possible flaws in the OPERA team's experiment pointed out by other scientists was the absence of energy loss by the neutrinos, which a pair of Boston University physicists argued would be detectable if the particles had traveled faster than light. Other scientists questioned whether the team had correctly accounted for the effects of relativity on the GPS satellites they used to measure the amount of time it took for the neutrinos to travel from point A to point B in their experiment.
The INFN team set out to re-run the neutrino experiment late last month. While results are not yet conclusive, the team says it's now ruled out a possible error in the measurement of the starting time for the neutrinos as they were fired from an accelerator in Geneva to the OPERA facility in Switzerland.
"A measurement so delicate and carrying a profound implication on physics requires an extraordinary level of scrutiny," said INFN president Fernando Ferroni. "The experiment OPERA, thanks to a specially adapted CERN beam, has made an important test of consistency of its result. The positive outcome of the test makes us more confident in the result, although a final word can only be said by analogous measurements performed elsewhere in the world."
Jacques Martino, director of the National Institute of Nuclear and Particle Physics of French CNRS, added that the team was re-checking other potential flaws in the original experiment.
"One of the eventual systematic errors is now out of the way, but the search is not over," Martino said. "There are more checks of systematics currently under discussion, one of them could be a synchronization of the time reference at CERN and Gran Sasso independently from the GPS.
Friday, November 18, 2011
Vatican miffed with Pope Kissing Imam (Ads)
The Vatican says it is taking legal action over the use of an ad showing Pope Benedict kissing a leading imam as part of a Benetton advertising campaign.
The Vatican move comes despite an announcement by the Italian clothing company that it was pulling the ad.
The ad, with its doctored image, is part of a global advertising campaign.
It consists of photo montages of political and religious leaders kissing each other on the mouth.
A statement said the Vatican had told its lawyers in Italy and around the world to "take the proper legal measures" to stop the use of the photo, even in the media.
It was not clear from the statement if the Vatican intended to sue Benetton directly for damages.
'Absurd'
The Vatican statement said the ad was "damaging to not only to dignity of the pope and the Catholic Church but also to the feelings of believers".
A spokesman for Egypt's al-Azhar institute, whose grand imam was pictured kissing the pope, described the advertisement as "irresponsible and absurd".
The spokesman, Mahmud Azab, told the French news agency AFP that the ad was so absurd that the institution was "still hesitating as to whether it should issue a response".
On Wednesday, Benetton pulled the ad showing Pope Benedict XVI kissing Egypt's Ahmed el Tayyeb, imam of the al-Azhar mosque in Cairo, after the Vatican launched a strong protest.
Other ads in the campaign feature US President Barack Obama kissing Chinese President Hu Jintao, and French President Nicolas Sarkozy with German Chancellor Angela Merkel.
In an initial protest on Wednesday, Vatican spokesman Federico Lombardi called the Benetton ad an "absolutely unacceptable use of the image of the Holy Father, manipulated and exploited in a publicity campaign with commercial ends.
"This shows a grave lack of respect for the pope, an offence to the feelings of believers, a clear demonstration of how publicity can violate the basic rules of respect for people by attracting attention with provocation," his statement said.
Shock ads
A large banner of the image showing the pope kissing the imam was hung from a bridge near the Vatican on Wednesday morning but later removed.
But on Thursday morning the picture was still in the window of a shop near Rome's Trevi Fountain, one of the most popular tourist sites in Rome.
The photo montage was still widely available on the internet on Thursday morning.
"We are sorry that the use of an image of the pontiff and the imam should have offended the sensibilities of the faithful in this way," Benetton said in a statement.
The purpose of the ad campaign, Benetton said in a statement, "was solely to battle the culture of hate in all its forms".
Benetton is no stranger to shock ad campaigns.
Previous controversial images it has used include death row inmates, a nun kissing a priest and a man dying of Aids.
Source: BBC
Saturday, October 8, 2011
Ozone in Venus?
Scientists have discovered that Venus has an ozone layer.
The thin layer, which is hundred of times less dense than the Earth's, was discovered by the European Space Agency's Venus Express craft,researchers report in the journal Icarus.
Until now, ozone layers have only been detected in the atmospheres of Earth and Mars.
The find could help astronomers refine their hunt for life on other planets.
The European spacecraft spied the ozone layer when focusing on stars through Venus' atmosphere.
The distant stars appeared fainter than expected, because the ozone layer absorbed some of their ultraviolet light.
The paper's lead author Franck Montmessin, of the LATMOS atmospheric research centre in France, explained that Venus' ozone layer sits 100km up; about three times the height of our own.
The ozone - a molecule containing three oxygen atoms - formed when sunlight broke down carbon dioxide in the Venusian atmosphere to form oxygen molecules.
On Earth, ozone, which absorbs much of the Sun's harmful UV-rays preventing them reaching the surface, is formed in a similar way.
However, this process is supplemented by oxygen released by carbon dioxide-munching microbes.
Ozoning in
Speaking of the international team's find, Hakan Svedhem, ESA project scientist for the Venus Express mission, said: "This ozone detection tells us a lot about the circulation and the chemistry of Venus's atmosphere.
"Beyond that, it is yet more evidence of the fundamental similarity between the rocky planets, and shows the importance of studying Venus to understand them all."
Some astrobiologists assume that the presence of oxygen, carbon, and ozone in an atmosphere indicates that life exists on a planet's surface.
The new results negate that assumption - the mere presence of oxygen in an atmosphere is now not enough evidence to start looking for life.
However, the presence of large quantities of these gases, as in the Earth's atmosphere, is probably still a good lead, the scientists said.
"We can use these new observations to test and refine the scenarios for the detection of life on other worlds," said Dr Montmessin.
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