Last week, Microsoft made the clearest case yet for its Surface Pro tablet when a top Windows executive said it should be compared with not one, but two Apple devices.
While analysts agreed that Microsoft's Surface Pro message was much clearer than the muddled one it offered last year for the Surface RT, and some saw the comparison as fair, others said it was wishful thinking on Microsoft's part,
To learn more and to read the entire article at its source, please refer to the following page, Microsoft pitches Surface Pro with Mac-iPad price comparison- Computerworld - New Zealand
DURHAM, N.C. (AP) ? Scottie Montgomery is coming back to Duke as its associate head football coach and receivers coach.
Coach David Cutcliffe said Monday that Montgomery would be his offensive coordinator in charge of the passing game.
Montgomery was an all-Atlantic Coast Conference receiver while playing for Duke from 1996-99, and he was an assistant coach under Cutcliffe and Ted Roof from 2006-09.
He spent the past three seasons as an assistant coach with the Pittsburgh Steelers.
He replaces Ron Middleton, who left last week for a spot on the Jacksonville Jaguars' staff.
JERUSALEM -- The head of a liberal Jewish women's group says Israeli police have detained 10 women, including the sister of American comic Sarah Silverman, as they tried to pray at a Jerusalem holy site.
Anat Hoffman says the women were detained for wearing religious garb that Orthodox Judaism reserves for men only. They were detained at the Western Wall, one of Judaism's holiest sites.
Silverman's sister Susan, a Jerusalem rabbi from the liberal Reform movement, was detained along with her teenage daughter. Hoffman says they are still in police custody.
Police spokesman Micky Rosenfeld confirmed the detentions.
About 300 people gathered Monday at the Western Wall to protest Orthodox control of the site.
Israel's prime minister has ordered officials to seek solutions for non-Orthodox women wishing to pray at the site.
Anyone interested in helping organise an Easter parade in Ilford Town Centre should go along to one of the weekly meetings being held every Tuesday.
Whether you are interested in getting your church or organisations involved, or just want to volunteer on the day, everyone is welcome.
The meetings are held each week at 7pm at the Ilford High Road Baptist Church, High Road, Ilford.
Wilson Chowdhry, of the Pakistani-Christian Association, said: ?The recent decline of those that profess to be Christians within the 2011 census made us want to really show we are a community and to express that Christianity is vibrant and relevant in today?s society.?
New material promises better solar cellsPublic release date: 12-Feb-2013 [ | E-mail | Share ]
Contact: Florian Aigner florian.aigner@tuwien.ac.at 43-158-801-41027 Vienna University of Technology
Researchers at the Vienna University of Technology show that a recently discovered class of materials can be used to create a new kind of solar cell
This press release is available in German.
Single atomic layers are combined to create novel materials with completely new properties. Layered oxide heterostructures are a new class of materials, which has attracted a great deal of attention among materials scientists in the last few years. A research team at the Vienna University of Technology, together with colleagues from the USA and Germany, has now shown that these heterostructures can be used to create a new kind of extremely efficient ultra-thin solar cells.
Discovering New Material Properties in Computer Simulations
"Single atomic layers of different oxides are stacked, creating a material with electronic properties which are vastly different from the properties the individual oxides have on their own", says Professor Karsten Held from the Institute for Solid State Physics, Vienna University of Technology. In order to design new materials with exactly the right physical properties, the structures were studied in large-scale computer simulations. As a result of this research, the scientists at TU Vienna discovered that the oxide heterostructures hold great potential for building solar cells.
Turning Light into Electricity
The basic idea behind solar cells is the photoelectric effect. Its simplest version was already explained by Albert Einstein in 1905: when a photon is absorbed, it can cause an electron to leave its place and electric current starts to flow. When an electron is removed, a positively charged region stays behind a so called "hole". Both the negatively charged electrons as well as the holes contribute to the electrical current.
"If these electrons and holes in the solar cell recombine instead of being transported away, nothing happens and the energy cannot be used", says Elias Assmann, who carried out a major part of the computer simulations at TU Vienna. "The crucial advantage of the new material is that on a microscopic scale, there is an electric field inside the material, which separates electrons and holes." This increases the efficiency of the solar cell.
Two Isolators Make a Metal
The oxides used to create the material are actually isolators. However, if two appropriate types of isolators are stacked, an astonishing effect can be observed: the surfaces of the material become metallic and conduct electrical current. "For us, this is very important. This effect allows us to conveniently extract the charge carriers and create an electrical circuit", says Karsten Held. Conventional solar cells made of silicon require metal wires on their surface to collect the charge carriers but these wires block part of the light from entering the solar cell.
Not all photons are converted into electrical current with the same efficiency. For different colors of light, different materials work best. "The oxide heterostructures can be tuned by choosing exactly the right chemical elements", says Professor Blaha (TU Vienna). In the computer simulations, oxides containing Lanthanum and Vanadium were studied, because that way the materials operate especially well with the natural light of the sun. "It is even possible to combine different kinds of materials, so that different colors of light can be absorbed in different layers of the solar cell at maximum efficiency", says Elias Assmann.
Putting Theory into Practice
The team from TU Vienna was assisted by Satoshi Okamoto (Oak Ridge National Laboratory, Tennessee, USA) and Professor Giorgio Sangiovanni, a former employee of TU Vienna, who is now working at Wrzburg University, Germany. In Wrzburg, the new solar cells will now be build and tested. "The production of these solar cells made of oxide layers is more complicated than making standard silicon solar cells. But wherever extremely high efficiency or minimum thickness is required, the new structures should be able to replace silicon cells", Karsten Held believes.
###
Further Information:
Prof. Karsten Held
Institute for Solid State Physics
Vienna University of Technology
Wiedner Hauptstrae 8-10, 1040 Vienna
T: +43-1-58801-13710
karsten.held@tuwien.ac.at
Dipl.-Ing. Elias Assmann
Institute for Solid State Physics
Vienna University of Technology
Wiedner Hauptstrae 8-10, 1040 Vienna
T: +43-1-58801-13759
elias.assmann@tuwien.ac.at
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
New material promises better solar cellsPublic release date: 12-Feb-2013 [ | E-mail | Share ]
Contact: Florian Aigner florian.aigner@tuwien.ac.at 43-158-801-41027 Vienna University of Technology
Researchers at the Vienna University of Technology show that a recently discovered class of materials can be used to create a new kind of solar cell
This press release is available in German.
Single atomic layers are combined to create novel materials with completely new properties. Layered oxide heterostructures are a new class of materials, which has attracted a great deal of attention among materials scientists in the last few years. A research team at the Vienna University of Technology, together with colleagues from the USA and Germany, has now shown that these heterostructures can be used to create a new kind of extremely efficient ultra-thin solar cells.
Discovering New Material Properties in Computer Simulations
"Single atomic layers of different oxides are stacked, creating a material with electronic properties which are vastly different from the properties the individual oxides have on their own", says Professor Karsten Held from the Institute for Solid State Physics, Vienna University of Technology. In order to design new materials with exactly the right physical properties, the structures were studied in large-scale computer simulations. As a result of this research, the scientists at TU Vienna discovered that the oxide heterostructures hold great potential for building solar cells.
Turning Light into Electricity
The basic idea behind solar cells is the photoelectric effect. Its simplest version was already explained by Albert Einstein in 1905: when a photon is absorbed, it can cause an electron to leave its place and electric current starts to flow. When an electron is removed, a positively charged region stays behind a so called "hole". Both the negatively charged electrons as well as the holes contribute to the electrical current.
"If these electrons and holes in the solar cell recombine instead of being transported away, nothing happens and the energy cannot be used", says Elias Assmann, who carried out a major part of the computer simulations at TU Vienna. "The crucial advantage of the new material is that on a microscopic scale, there is an electric field inside the material, which separates electrons and holes." This increases the efficiency of the solar cell.
Two Isolators Make a Metal
The oxides used to create the material are actually isolators. However, if two appropriate types of isolators are stacked, an astonishing effect can be observed: the surfaces of the material become metallic and conduct electrical current. "For us, this is very important. This effect allows us to conveniently extract the charge carriers and create an electrical circuit", says Karsten Held. Conventional solar cells made of silicon require metal wires on their surface to collect the charge carriers but these wires block part of the light from entering the solar cell.
Not all photons are converted into electrical current with the same efficiency. For different colors of light, different materials work best. "The oxide heterostructures can be tuned by choosing exactly the right chemical elements", says Professor Blaha (TU Vienna). In the computer simulations, oxides containing Lanthanum and Vanadium were studied, because that way the materials operate especially well with the natural light of the sun. "It is even possible to combine different kinds of materials, so that different colors of light can be absorbed in different layers of the solar cell at maximum efficiency", says Elias Assmann.
Putting Theory into Practice
The team from TU Vienna was assisted by Satoshi Okamoto (Oak Ridge National Laboratory, Tennessee, USA) and Professor Giorgio Sangiovanni, a former employee of TU Vienna, who is now working at Wrzburg University, Germany. In Wrzburg, the new solar cells will now be build and tested. "The production of these solar cells made of oxide layers is more complicated than making standard silicon solar cells. But wherever extremely high efficiency or minimum thickness is required, the new structures should be able to replace silicon cells", Karsten Held believes.
###
Further Information:
Prof. Karsten Held
Institute for Solid State Physics
Vienna University of Technology
Wiedner Hauptstrae 8-10, 1040 Vienna
T: +43-1-58801-13710
karsten.held@tuwien.ac.at
Dipl.-Ing. Elias Assmann
Institute for Solid State Physics
Vienna University of Technology
Wiedner Hauptstrae 8-10, 1040 Vienna
T: +43-1-58801-13759
elias.assmann@tuwien.ac.at
[ | E-mail | Share ]
?
AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert! system.
President Barack Obama on Monday awarded former Army Staff Sgt. Clinton Romesha the Medal of Honor for actions taken in a 2009 firefight in Afghanistan.
Obama, during a ceremony held in the White House's East Room, detailed the heroism Romesha displayed on Oct. 3, 2009 when 300 Taliban fighters descended upon the 53 Americans at Army outpost Keating on the border of Pakistan under "almost unbelievable conditions," Obama said.
"That?s what these soldiers were asked to do-- defend the indefensible," Obama said of the outpost, which was situated at the bottom of a steep valley which left the soldiers open to attack.
"Explosions shook them out of their beds," that morning, Obama said, setting off "what?s been called one of the most intense battles of the entire war in Afghanistan."
Romesha sat, visibly displaying emotion, as the president detailed that day, which Romesha has emphasized was a team effort.
The soldiers faced rocket propelled grenades, machine guns, grenades, mortars and snipers. Romesha attacked and took out an enemy machine gun team, sustained shrapnel injuries in his hip, neck and arm, and continued fighting and tending to members of his unit. Romesha took a "100 meter run through a hail of bullets," Obama said, to reach his "fallen friends."
He "continually exposed himself to heavy enemy fire," read Romesha's award citation.
Romesha and his family currently live in Minot, N.D.
The Medal of Honor is awarded to members of the Armed Forces who display "gallantry above and beyond the call of duty."
From the White House: "The meritorious conduct must involve great personal bravery or self-sacrifice so conspicuous as to clearly distinguish the individual above his or her comrades and must have involved risk of life. There must be incontestable proof of the performance of the meritorious conduct, and each recommendation for the award must be considered on the standard of extraordinary merit."
U.S. presidents have awarded over 3,400 medals since its creation in 1861.
A satellite in orbit captured the birth of mega-snowstorm Nemo Saturday (Feb. 9) as the blizzard dumped feet of snow on New England and other parts of the Northeast.
The video of snowstorm Nemo from space was recorded by the GOES-13 weather satellite from Thursday (Feb. 7) through early Saturday, as two low-pressure weather systems collided to form a single, giant nor'easter. According to NASA's GOES Project officials, "the two systems came together and created a blizzard of historic proportions in New England."
"On Feb. 9 at 4 a.m., hundreds of thousands of people were without power in Massachusetts alone," GOES Project officials wrote in a video description.
Snowstorm Nemo buried much of the Northeast in more than 2 feet of snow, with the storm being blamed for at least four deaths, according to press reports.
The GOES-13 satellite video shows the storm form over two days as a powerful Alberta Clipper system carrying cold Arctic air from Western Canada slammed into a low-pressure system that moved northward from the Gulf Coast in the south. ?
GOES-13 is operated by the National Oceanic and Atmospheric Administration (NOAA), which oversees a fleet of Earth-watching satellites with NASA to monitor the planet's weather systems.
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Public release date: 12-Feb-2013
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