Issue no. 11, 2010
Published: Mar 26, 2010 |
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 Large Hadron Collider to start hunt for Higgs boson |
| Light bends matter, surprising scientists |
| Babbage nanomachine promises low-energy computing |
| Researchers design elastic iron for surgeries, buildings |
| Prizewinning math could reveal hidden patterns in primes |
| Quantum tech boosts phone cameras |
| Researchers create 'handshaking' particles |
| Researchers develop desalination on a chip |
| Rankings cut guesswork in sustainable fish farming |
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| Large Hadron Collider to start hunt for Higgs boson |
The organisation that operates the Large Hadron Collider has set a date
for the start of its science programme. On Tuesday 30 March, engineers
at CERN will make their first attempt to collide beams at an energy of
3.5 trillion electronvolts (TeV) per beam. The LHC reached this beam
energy last week, breaking its own particle beam energy record.
But, among other things, engineers will need to ensure the beams are
stable at 3.5 TeV before trying for collisions. Between now and 30
March, the LHC's team will be working to commission the beam control
systems and the systems that protect the machine's detectors, or
experiments, from stray particles. All these systems must be fully
commissioned before collisions at 3.5 TeV can begin, CERN says.
The LHC is being used to smash together beams of proton particles in a
bid to shed light on the nature of the Universe. Some 1,200
superconducting magnets bend proton beams in opposite directions around
the tunnel at close to the speed of light. At allotted points around the
tunnel, the proton beams cross paths, allowing particles to smash into
one another. Detectors located at the crossing points will scour the
wreckage of these collisions for discoveries that extend our knowledge
of physics, notably the elusive Higgs boson, predicted to exist by the
Standard Model in particle physics. |
| BBC News
Mar 23, 2010 |
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| Light bends matter, surprising scientists |
Light can twist matter, according to a new study that observed ribbons
of nanoparticles twisting in response to light. Scientists knew matter
can cause light to bend - prisms and glasses prove this easily enough.
But the reverse phenomenon was not shown to occur until recently.
In a darkened lab, scientists at the University of Michigan linked
nanoparticles together into ribbons. At first the nano ribbons were
flat, but when a light was shone on them, they curled up into spirals.
The discovery was so novel, the researchers were sceptical of their own
results at first.
The surface of the nanoparticles in this experiment were made of cadmium
sulfide. To begin with, they had a slightly negative electromagnetic
charge. But when photons hit the nanoparticles their energy excited
electrons on the nanoparticles, causing chemical reactions that made
them even more negatively charged. Since two negative charges repel each
other, the nanoparticles began to repel more strongly. |
| MSNBC / Science
Mar 24, 2010 |
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| Babbage nanomachine promises low-energy computing |
Not only did Charles Babbage lay the foundations for the computer
revolution, his designs for mechanical computers also provide a
blueprint for energy efficiency. So say researchers at Boston University
who have created a nanoscale mechanical logic gate that could form the
basis of tiny mechanical computers. The mechanical logic gate is slower
than its traditional equivalent, but loses far less energy
The gate consists of a strip of silicon 300 nanometres wide sitting
between two chunks of silicon. Applying a voltage between one chunk and
the strip causes the strip to vibrate, like the reed in a clarinet. With
the right voltage, the strip will enter a so-called hysteretic regime -
where it will vibrate with one of two amplitudes.
By using a pair of electrical pulses that work with the resonating strip
to provide that kick in potential, the team were able to flip the
vibration from one amplitude to the other. If just one of the pulses -
or neither of them - resonates with the strip then it remains in its
existing vibrational state. In other words, the device acts as an AND
logic gate. While the gate is not as fast as its traditional equivalent,
it loses far less energy per operation, according to the team. Trading
speed for energy might be beneficial in some situations. |
| New Scientist / Nano Letters
Mar 25, 2010 |
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| Researchers design elastic iron for surgeries, buildings |
Researchers at Tohoku University in Japan have designed a super-elastic
iron alloy which they hope can be used in sophisticated heart and brain
surgeries and even buildings in earthquake zones.
The metal's super-elasticity allows it to return to its original form
and gives it additional properties, such as ductility and a change in
magnetization, according to the researchers.
The iron alloy's stress level is about twice that of nickel titanium and
it can be used to deliver stents, which are tubes placed in blood
vessels to stop them from collapsing. The super-elastic iron alloy may
also be used for buildings in earthquake prone areas. |
| Reuters / Science
Mar 19, 2010 |
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| Prizewinning math could reveal hidden patterns in primes |
A USD 1m prize has been awarded to a mathematician for work that could
one day unlock the secrets of prime numbers. The King of Norway will
officially present the prestigious Abel prize in May to John Tate, who
recently retired from the University of Texas at Austin.
The award honours Tate's work on number theory, a branch of mathematics
that stretches back to ancient Greece. It deals with patterns of numbers
and their properties and is crucial in keeping the internet secure. Tate
created many of the tools used to explore this world of numbers, and his
influence is reflected in the sheer number of mathematical ideas that
bear his name.
Tate's research helped prove Fermat's Last Theorem, which puzzled
mathematicians for over 350 years until it was solved by Andrew Wiles in
1995. Future Abel prizewinners may also benefit from Tate's theories, as
his doctoral thesis supplies the techniques needed to attack one of the
hardest problems in mathematics: the origin of prime numbers.
Mathematicians have known for thousands of years that there are an
infinite number of primes, but they don't have an obvious pattern.
Deciphering their distribution seems to depend on a formula for an
infinite sum of numbers called the Riemann zeta function, which creates
a mathematical landscape. Tate's analysis shed new light on the zeta
function, enabling mathematicians to further investigate its landscape. |
| New Scientist
Mar 25, 2010 |
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| Quantum tech boosts phone cameras |
Tiny semiconductor particles known as 'quantum dots' have been used in a
sensor that could make for mobile phone cameras that outperform larger
cousins. A film made from these dots is more light-sensitive than
existing approaches to camera sensors, according to its makers,
Invisage. That means that cameras made using the film need not be as
large as some to achieve the same performance.
Digital camera sensors rely on silicon to turn incoming light into an
electric charge that the camera can measure and translate into an image.
But the way silicon-based sensors are produced means that in many cases
the light is partially blocked by the electronic connections that make
the sensor work. Combined with the fact that silicon can turn only half
of the incident light into electric charge, capturing light using
silicon throws away about 75% of the light.
That is where quantum dots come in. They are so named because they are
single, tiny dots of semiconductor material whose light-absorbing
properties - their predilection to absorb specific 'quanta' of light
energy - can be tightly controlled during manufacture. Invisage makes a
soup of these quantum dots and spins it into a so-called QuantumFilm.
The firm said the approach could be easily integrated to existing
semiconductor manufacturing methods. Because each quantum dot is so
small, up to three times as many 'pixels' can be squeezed into a given
space, and the higher sensitivity gives better performance in low-light
conditions. |
| BBC News
Mar 22, 2010 |
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| Researchers create 'handshaking' particles |
Physicists at New York University have created 'handshaking' particles
that link together based on their shape rather than randomly. Their work
marks the first time scientists have succeeded in 'programming'
particles to join in this manner and offers a type of architecture that
could enhance the creation of synthetic materials.
The process is centred on creating and manipulating colloids-particles
suspended within a fluid medium. Colloidal dispersions comprise such
everyday items as milk, gelatine, glass, and porcelain. Working with
microscopic particles-25 placed together, end-to-end, would match the
width of a strand of human hair-the researchers developed a 'lock and
key' mechanism that would allow specific particles to join together much
in the way Pac-Man would swallow dots in the 1980s video game.
The 'key' is any spherical particle. Creating the 'lock', however,
required a multi-step polymerisation process. To do it, the researchers
took a droplet of oil and placed it in water. The process resulted in a
hardened outer shell, which would then buckle to form an indentation, or
Pac-Man mouth, allowing it to bind to the other sphere, the 'key'. |
| Physorg / Nature
Mar 24, 2010 |
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| Researchers develop desalination on a chip |
Scientists have made a nanotech device to strip salt from seawater,
paving the way to small-scale, battery-powered desalination for
drought-hit regions and disaster zones.
Conventional desalination works by forcing water through a membrane to
remove molecules of salt. But this process is an energy-gobbler and the
membrane is prone to clogging, which means desalination plants are
inevitably big and expensive.
The new device has been given a proof-of-principle test by scientists at
MIT. It works through so-called ion concentration polarisation, which
occurs when a current of charged ions is passed through an ion-selective
membrane. The idea is to create a force that moves charged ions and
particles in the water away from the membrane.
When the water passes through the system, salt ions - as well as cells,
viruses and micro-organisms - get pushed to the side. This saltier water
is then drawn off, leaving only de-salinated water to pass through the
main microchannel. The tiny device had a recovery rate of 50%, meaning
that half of the water used at the start was desalinated; 99% of the
salt in this water was removed. Energy efficiency was similar to or
better than state-of-the-art large-scale desalination plants. |
| ABC / AFP / Nature Nanotechnology
Mar 22, 2010 |
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| Rankings cut guesswork in sustainable fish farming |
Fish-lovers may soon be able to buy guilt-free farmed seafood, thanks to
a new league table that ranks the sustainability of the fisheries used
to make feed for aquaculture. The league table will help farms make sure
the feed they use does not harm wild fish stocks and could allow them to
qualify for schemes certifying that their produce is sustainable.
With farmed fish there is the challenge of defining whether the feeds
used in aquaculture come from sustainable sources. Farmed fish are fed
oils and meal made from other fish. This has led to some drastic
declines in wild fish populations.
Now the Sustainable Fisheries Partnership, a nonprofit group based in
San Francisco, has published a sustainability league table for the 22
fish stocks most harvested for fish oil and fishmeal. Their report gives
fisheries marks out of 10 in five key areas: whether there is a
mechanism to reduce catches if stocks decline, whether fishery managers
follow scientific advice, whether fleets comply with specified limits on
their catch, whether stock levels are healthy now and whether they are
likely to be healthy in future.
The first consumer labelling schemes for farmed fish could be launched
in 2012, including one run by the Aquaculture Stewardship Council, a
nonprofit organisation based in Utrecht, The Netherlands. |
| New Scientist
Mar 25, 2010 |
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