GEN-ERIC News

A game of billiards may never get smaller than this. Physicists at UC Riverside have demonstrated that graphene – a one-atom thick sheet of carbon atoms arranged in hexagonal rings – can act as an atomic-scale billiard table, with electric charges acting as billiard balls. The finding underscores graphene’s potential for serving as an excellent electronic material, such as silicon, that can be used to develop new kinds of transistors based on quantum physics. Because they encounter no obstacles, the electrons in graphene roam freely across the sheet of carbon, conducting electric charge with extremely low resistance. The research team, led by Chun Ning (Jeanie) Lau, found that the electrons in graphene are reflected back by the only obstacle they meet: graphene’s boundaries. “These electrons meet no other obstacles and behave like quantum billiard balls,” said Lau, an assistant professor who joined UCR’s Department of Physics and Astronomy in 2004. “They display properties that resemble both particles and waves.” Lau observed that when the electrons are reflected from one of the boundaries of graphene, the original and reflected components of the electron can interfere with each other, the way outgoing ripples in a pond might interfere with ripples reflected back from the banks.

The duck diver is designed for use in fairly shallow water, and consists of yellow plastic tubing connected in a square shape with a hollow center. The plastic square is attached by a rod to the sea floor, with a lever that allows the device to adjust its height between low and high tides. The ability to endure different water levels, Olson explains, has been a challenge for many ocean energy converters in the past. This flexibility, coupled with the device’s robustness, also enables the duck diver to withstand large waves by submerging itself vertically under the water–hence its name. And, like a duck or other floating object, the device moves toward a wave as it approaches, and then is pushed back by the wave as it passes. The device captures the horizontal push and vertical lift of the waves, as the waves pass by again and again. This energy can then be transferred to a generator and converted to electricity. Olson demonstrates a single device supplying enough energy to power 100 1.6-volt LEDs, in relatively calm water. Better yet, each device costs just $65 to make, is designed to survive for 10 years without maintenance, and can be constructed by someone with “general mechanical knowledge.”

New research led by the U.S. Department of Energy’s Argonne National Laboratory physicist Matthias Bode provides a more thorough understanding of new mechanisms, which makes it possible to switch a magnetic nanoparticle without any magnetic field and may enable computers to more accurately write and store information. Bode and four colleagues at the University of Hamburg used a special scanning tunneling microscope equipped with a magnetic probe tip to force a spin current through a small magnetic structure. The researchers were able to show that the structure’s magnetization direction is not affected by a small current, but can be influenced if the spin current is sufficiently high.

1814: Francis Scott Key composed the lyrics to The Star Spangled Banner.

1901: President McKinley died of gunshot wounds inflicted by an assassin. Vice President Theodore Roosevelt succeeded him.

1940: Congress passed the Selective Service Act, providing for the first peacetime draft in U.S. history.

1959: The Soviet space probe Luna 2 became the first man-made object to reach the Moon when it crashed onto the lunar surface.

1982: Princess Grace of Monaco died from injuries sustained in a car crash the previous day.

1994: Acting commissioner Bud Selig announced the cancellation of the 1994 baseball season on the 34th day of a strike by players.

Twice as many girls as boys are being born in some Arctic villages because of high levels of man-made chemicals in the blood of pregnant women, according to scientists from the Arctic Monitoring and Assessment Programme (Amap). The scientists, who say the findings could explain the recent excess of girl babies across much of the northern hemisphere, are widening their investigation across the most acutely affected communities in Russia, Greenland and Canada to try to discover the size of the imbalance in Inuit communities of the far north. In the communities of Greenland and eastern Russia monitored so far, the ratio was found to be two girls to one boy. In one village in Greenland only girls have been born. The scientists measured the man-made chemicals in women’s blood that mimic human hormones and concluded that they were capable of triggering changes in the sex of unborn children in the first three weeks of gestation. The chemicals are carried in the mother’s bloodstream through the placenta to the foetus, switching hormones to create girl children. Lars-Otto Reierson, executive secretary for Amap, said: “We knew that the levels of man-made chemicals were accumulating in the food chain, and that seals, whales and particularly polar bears were getting a dose a million times higher than that existing in plankton, and that this could be toxic to humans who ate these higher animals. What was shocking was that they were also able to change the sex of children before birth.”

Easy-to-remove chewing gum is to become a reality, thanks to a major technological break-through. The announcement will be made this week at the BA Festival of Science in York. Revolymer, a spin out company from the University of Bristol, has completed development of its new Clean Gum that can be easily removed from shoes, clothes, pavements and hair. Preliminary results also indicate that the gum will degrade naturally in water. The company has completed initial street trials on pavements in local high streets as part of a collaborative agreement with local councils. In the two trials, leading commercial gums remained stuck to the pavements three out of four times. In all tests the Revolymer gum was removed within 24 hours by natural events. Professor Terence Cosgrove, of the University of Bristol and Chief Scientific Officer of Revolymer said: “The advantage of our Clean Gum is that it has a great taste, it is easy to remove and has the potential to be environmentally degradable.” “The basis of our technology is to add an amphiphilic polymer to a modified chewing gum formulation which alters the interfacial properties of the discarded gum cuds, making them less adhesive to most common surfaces.”

A Singapore-developed microneedle process used in Hewlett-Packard’s inkjet cartridges could soon be used in skin patches to administer drugs. The locally-developed microneedle technology is used in Hewlett-Packard’s patented process for its inkjet cartridges, could soon be used in transdermal patches to deliver time-controlled release of drugs to patients. HP announced Tuesday that it will license its microneedle technology to Crospon, an Ireland-based medical device maker, to develop and manufacture drug-laden skin patches for the healthcare market. In a phone interview with ZDNet Asia, Crospon CEO John O’Dea said that the skin patch is akin to “a very small infusion pump". Still at the prototype stage, the patch will likely be 25 mm square in size and 3 mm thick. It will incorporate an array of microneedles that are between 75 and 100 microns, which will penetrate the top dry layer of the skin, also known as the stratum corneum.

Visible and ultraviolet laser light has been used for years to cool trapped atoms—and more recently larger objects—by reducing the extent of their thermal motion. Now, applying a different form of radiation for a similar purpose, physicists at the National Institute of Standards and Technology (NIST) have used radio waves to dampen the motion of a miniature mechanical oscillator containing more than a quadrillion atoms, a cooling technique that may open a new window into the quantum world using smaller and simpler equipment. Described in a forthcoming issue of Physical Review Letters,* this demonstration of radio-frequency (RF) cooling of a relatively large object may offer a new tool for exploring the elusive boundary where the familiar rules of the everyday, macroscale world give way to the bizarre quantum behavior seen in the smallest particles of matter and light. There may be technology applications as well: the RF circuit could be made small enough to be incorporated on a chip with tiny oscillators, a focus of intensive research for use in sensors to detect, for example, molecular forces.