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Thursday, May 31, 2012

[QUICK] Solar Impulse landed in Madrid

Science and techno world topic: Technology

Takeoff of the HB-SIA "Solar Impulse" base of Payerne, Switzerland, May 24, 2012.

After a flight lasting approximately 17 hours, the Solar Impulse plane finally landed at the airport of Madrid-Barajas in the night from Thursday to Friday. He had taken off early in the morning of Thursday the airfield of Payerne, Switzerland. "The flight went well and thanks to the team of meteorologists, everything went according to the flight plan," said the pilot, André Borschberg.
The prototype HB-SIA Sloar impulse is powered by four electric motors, a power of 10 hp each, powered by 12,000 photocells on its wings spread as wide as those of an Airbus A340. Energy is stored in batteries, allowing the aircraft to fly at night. The first step is being proceeded smoothly, the aircraft is expected to resume next week's trip destination Morocco, with orders to the explorer Bertrand Piccard. This is a test flight before a world tour planned in 2014.

Tuesday, May 29, 2012

Planet of diamond

Science and techno world topic: Space

Some stars may be orbited by planets diamond. This possibility opens experiments and calculations of American geoscientists. If the birth of a star cloud abundant carbon, it can be compressed deep inside of planets to diamond.
In a sample have been under high pressure and temperature dark grains of wustite (iron (II) oxide, center) and diamond (right) is formed.
Photo: Ohio State University

Especially with larger planets, this process could come to fruition, Born Under Cayman explained by the Ohio State University. "It is conceivable that there are planets with up to 15 Earth masses, half of diamond," says the researcher. Since diamond is a very good conductor of heat, but such worlds are likely to cool rapidly and therefore be extremely inhospitable.

The structure of the Earth with its iron core and its silicate rocks probably reflects reflect the composition of the gas and dust cloud that have evolved out of the sun and its planets. Born and colleagues were now under the question might look like the inside of rocky planets, which have emerged from a highly carbonaceous cloud. The researchers used this sample of iron, carbon and oxygen pressures of up to 65 gigapascals (650,000 atmospheres) and temperatures of more than 2,100 degrees Celsius, as they exist in the mantle. With the so obtained data they fed a thermochemical model planet.

Are deep inside a rocky planet is carbon, therefore, not only in oxidized form in minerals. Part of it lies rather in plain carbon, which can be transformed under the weight of several hundred kilometers of rock into diamond. In addition, a portion of the carbon reacts with iron to form iron carbide, which sank into the planet core. The oxygen reacts with the iron and thus forms the iron mineral wustite.

Analogous to the Earth could form apparently also in carbon planets core and mantle, concludes Wendy Panero, the head of the research group. "The core would be highly carbonaceous and would thus resemble steel, while the carbon-rich shell stocks in large part made of diamond." Because such a planet auskühle quickly, he as probably only temporarily to a magnetic field, plate tectonics and an atmosphere, the researcher . "We believe that a diamond planet is a very cold and dark world."

Research: Under Cayman T. Born, Wendy R. Panero and Jason E. Kabbes, School of Earth Sciences, Ohio State University, Columbus
Presentation at the 2011 Fall Meeting of the American Geophysical Union, San Francisco; # P21C-1679


Spider silk conducts heat better than metals

Science and techno world topic: Physics
Spider silk fascinated materials scientists, because they are very resistant to tearing and yet elastic.Another amazing feature of American engineers have discovered: The threads of golden silk spider conduct heat much better than most of the known materials.

"This is more surprising than spider silk is an organic material," says Wang Xinwei of the Iowa State University. The reason for the high thermal conductivity lies presumably in the structure of the silk protein from crystalline molecule blocks, which are in turn connected via flexible bridges.

Photo: Xinwei Wang Research Group

The higher the thermal conductivity of a material is, the faster heat energy can at a given temperature difference to flow through it. Pure iron as a good conductor of heat and has a value of about 80 watts per meter per degree Celsius temperature difference. Copper bumps this up to five times. The dragline silk of the golden spider on the other hand creates 416 watts per meter per degree, Wang and colleagues report in the journal "Advanced Materials".
If the silk thread drawn out, its thermal conductivity increases again by a fifth and then surpasses even that of silver. Better conductor of heat is only diamond or nanotubes of pure carbon - according to Wang's revolutionizing the new results to date views on the thermal conductivity of organic materials. May thus open up a new path, the thermal behavior of electronic components, or even to improve on clothes, said the researchers.

Research: Xiaopeng Huang, Guoqing Liu, Xinwei Wang, Department of Mechanical Engineering, Iowa State University, Ames
Publication of Advanced Materials, DOI 10.1002/adma.201104668

Computer translate the brain signals

Science and techno world topic: Computer
If the nerve connection between the brain and muscles is interrupted, an electronic bypass to restore at least part of the movement. This is shown by experiments on monkeys, American physicians have performed. The animals were able to handle with a ball by the control signals have been translated by computer into her brain stimulation currents for the arm muscles.

"This achievement is an important step towards the restoration of hand function in human patients," are convinced Lee Miller of Northwestern University in Chicago and his colleagues. Although only three flexor muscles were activated, the monkeys were able to grab hold a weighted rubber ball, and put in a bin, the researchers report in the journal "Nature".