| Issue no. 31, 2010
Published: Oct 08, 2010
| Duo wins 2010 physics Nobel for super-thin carbon|
| First frictionless superfluid created|
| A painless way to achieve huge energy savings: Stop wasting food|
| Clippers set sail for space|
| European satellite 'blinded' by radio interference|
| Is solar wind the next renewable energy resource?|
| It pays not to cultivate GM crops, survey finds|
|Duo wins 2010 physics Nobel for super-thin carbon
|Two Russian-born scientists shared the 2010 Nobel Prize for physics for
showing how carbon just one atom thick behaved, a discovery with
profound implications from quantum physics to consumer electronics.
Andre Geim and Konstantin Novoselov of the University of Manchester in
England conducted experiments with graphene. One hundred times stronger
than steel, it is a new form of carbon that is both the thinnest and
toughest material known. Novoselov, 36, is a dual British-Russian
citizen while Geim, 51, is a Dutch citizen.
The pair extracted the material from a piece of graphite such as that
found in ordinary pencils using adhesive tape, repeating the trick until
they were left with minuscule flakes of graphene. They unveiled the
discovery 6 years ago.
The academy said that graphene offered physicists the ability to study
two-dimensional materials with unique properties and made possible
experiments that can give new twists to the phenomena in quantum
physics. Mentioning a few possible applications, the academy said
graphene transistors were expected to become much faster than today's
silicon ones and yield more efficient computers.
Oct 05, 2010
|| back to top
|First frictionless superfluid created
|Superfluidity is a bizarre consequence of quantum mechanics. Cool helium
atoms close to absolute zero and they start behaving as a single quantum
object rather than a group of individual atoms. At this temperature, the
friction that normally exists between atoms, and between atoms and other
objects, vanishes, creating what is known as a superfluid.
To see if molecules could be made superfluid, researchers of the
National Research Council of Canada turned to hydrogen, which exists as
pairs of atoms. The team created a compressed mixture of hydrogen and
carbon dioxide gas and shot it through a nozzle at supersonic speeds.
Once released, the molecules spread apart, cooling and arranging
themselves so that each CO2 molecule sat at the centre of a cluster of
up to 20 hydrogens.
To test for superfluidity, the team shone an infrared laser at the
clusters at wavelengths that CO2, but not hydrogen, can absorb. This set
only the CO2 molecules vibrating. Under normal conditions this movement
would be slowed down due to friction between the moving CO2 molecules
and the surrounding hydrogen. But the researchers found that for
clusters of 12 hydrogen molecules, the hydrogen barely impeded the
motion of the CO2 and are 85 per cent superfluid.
As hydrogen is only the second element known to form a superfluid, the
experiment could be useful for disentangling general qualities of
superfluids. Superfluid molecules might also be used as 'nano-fridges',
which surround and cool individual protein molecules.
| New Scientist / Physical Review Letters
Oct 07, 2010
|| back to top
|A painless way to achieve huge energy savings: Stop wasting food
|Scientists have identified a way that the United States could
immediately save the energy equivalent of millions of barrels of oil a
year - without spending a penny or putting a ding in the quality of
life: Just stop wasting food.
The study found that it takes the equivalent of around 1.4bn barrels of
oil to produce, package, prepare, preserve and distribute a year's worth
of food in the US. The researchers note that food contains energy and
requires energy to produce, process, and transport. Estimates indicate
that between 8 and 16% of energy consumption in the US went toward food
production in 2007. The US Department of Agriculture estimates that
people in the US waste about 27% of their food.
The scientists realised that the waste might represent a largely
unrecognized opportunity to conserve energy and help control global
warming. Their analysis of wasted food and the energy needed to ready it
for consumption concluded that the US wasted the equivalent of around
350 million barrels of oil. That represents around 2% of annual energy
consumption in the US.
| PhysOrg / ACS' journal Environmental Science & Technology
Oct 03, 2010
|| back to top
|Clippers set sail for space
|Engineers at Thales Alenia Space in France say it is possible to slash
the amount of time needed to transport planetary data back to Earth by
using spacecraft propelled by solar radiation. These 'data clippers'
could in principle shuttle continuously between Earth and the outer
planets, returning large volumes of data decades earlier than is
possible with conventional radio transmissions.
Satellites studying planetary bodies that are relatively nearby, such as
the Moon and Mars, can transmit data back to Earth fairly quickly via a
radio link. Missions observing more distant planets, however, face a
problem because the signal over these greater distances becomes
sufficiently weak that transmission must be slowed down in order to
guarantee that radio antennas on Earth can intercept the data. For
instance, sending data from Jupiter via a radio link cannot go faster
than about 1 gigabyte per day.
The researchers propose the use of data clippers. These spacecraft would
use large lightweight 'sails' that are pushed forward by the very slight
but continuous radiation pressure of the photons emitted by the Sun.
These clippers could be directed around the solar system so that they
pass close to conventional spacecraft orbiting distant planets or moons,
upload data from the spacecraft and then perform a flyby of Earth,
during which they download the data to a ground station.
By passing within a few tens of thousands of kilometres of the orbiting
spacecraft and of Earth, the divergence of the laser beam would be small
enough to guarantee a fast data transmission rate - up to 1 gigabyte per
second - and the data transport would therefore be limited simply by the
time that it takes the clipper to travel from the planetary body back to
Oct 05, 2010
|| back to top
|European satellite 'blinded' by radio interference
|The European Space Agency (ESA) said on Wednesday that it had launched a
behind-the-scenes campaign to shut down illicit radio and TV
transmissions interfering with a major climate satellite. The Soil
Moisture and Ocean Salinity (SMOS) probe 'has been bugged by patches of
interference from radar, TV and radio transmissions in what should be a
protected band,' ESA complained.
SMOS orbits 760 kilometres above Earth, a low-altitude slot enabling it
to gauge the impact of climate change on the movement of water across
land, air and sea. Soon after launch last November 2, scientists
realised that interference was 'effectively blinding' the probe as it
passed over parts of southern Europe, Asia, the Middle East and some
coastal zones. The intrusion has two causes.
One is a leakover into a band of the electromagnetic spectrum (1400-1427
MHz in the L-band) which is assigned to space astronomy and Earth
exploration satellites by the International Telecommunications Union
(ITU). This source came from overpowerful transmitters in adjacent
bands, ESA said. The other cause is illegal transmissions by TV, radio
links and networks such as security systems that are blasting into the
precious radio band.
The agency said it had had to embark upon 'the tricky and lengthy
process' of having the illegal transmissions shut down and the excessive
out-of-band emissions reduced. Its first approach had been to
governments in Europe, which were tracking down the sources and having
the devices retuned or shut down. As a result, interference is on the
wane, it said.
| Yahoo / AFP
Oct 06, 2010
|| back to top
|Is solar wind the next renewable energy resource?
|Solar and wind power have long been two of the main contenders in the
race to find the next big renewable energy resource. Rather than
choosing between the two, scientists at Washington State University have
instead combined them.
Using a massive 8,400-km-wide solar sail to harvest the power in solar
wind, the team hopes their concept could generate 1 billion billion
gigawatts of power, which is approximately 100 billion times the power
humanity currently uses - if they can get that power back to Earth. The
proposed satellite would use a charged copper wire to capture electrons
zooming away from the sun at several hundred kilometres per second.
Of course, all of that power has to be able to get to Earth. Some of the
energy the satellite generates would be pumped back into the copper wire
to create the electron-harvesting magnetic field. The rest of the energy
would power an infrared laser beam, which would help fulfil the whole
planet's energy needs day and night regardless of environmental
The main shortfall of this approach is that over the millions of
kilometres between the satellite and Earth, even the tightest laser beam
would spread out and lose a lot of its original energy. While most of
the technology to create the satellite already exists, a more focused
laser would be necessary.
| MSNBC / Discovery Channel
Sep 30, 2010
|| back to top
|It pays not to cultivate GM crops, survey finds
|The first economic analysis of growing genetically modified crops on a
wide scale has found that the biggest winners were the farmers who
decided not to grow them. The study, which looked at maize yields in the
corn belt of the United States, found that farmers who continued to grow
conventional crops actually earned more money over a 14-year period than
those who cultivated GM varieties.
GM maize has a bacterial gene called 'Bt' added to it so that the plant
excretes a protein which has a toxic effect on the European corn borer,
a serious insect pest introduced accidentally into America in 1917.
Nearly two-thirds of the US corn belt is now cultivated with Bt maize,
and it has had a dramatic impact on the decline of the corn borer moth,
which cannot distinguish between the GM and conventional varieties. When
female moths lay their eggs on Bt corn, the larvae die within two days
Paul Mitchell, an agricultural economist at the University of
Wisconsin-Madison where the work was carried out, said the main
corn-growing states of Wisconsin, Minnesota, Illinois, Iowa and Nebraska
experienced a total economic benefit of USD 6.9bn over the period from
1996 to 2009 as a result of less maize being lost to the corn-borer
pest. But the non-GM corn areas accounted for 62% of this total economic
benefit because, in addition to preventing crop losses resulting from
lower levels of pests, these farmers did not have to spend any extra
money on the technology fees associated with the purchase of GM maize.
| The Independent / Science
Oct 08, 2010
|| back to top