Saturn propellers reflect solar system origins
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 Scientists using NASA's Cassini spacecraft at Saturn have stalked a new class of moons in the rings of Saturn that create distinctive propeller-shaped gaps in ring material. It marks the first time scientists have been able to track the orbits of individual objects in a debris disk. The research gives scientists an opportunity to time-travel back into the history of our solar system to reveal clues about disks around other stars in our universe that are too far away to observe directly."Observing the motions of these disk-embedded objects provides a rare opportunity to gauge how the planets grew from, and interacted with, the disk of material surrounding the early sun," said Carolyn Porco, Cassini imaging team lead based at the Space Science Institute in Boulder, Colo., and a co-author on the paper. "It allows us a glimpse into how the solar system ended up looking the way it does."The results are published in a new study in the July 8, 2010, issue of the journal Astrophysical Journal Letters.Cassini scientists first discovered double-armed propeller features in 2006 in an area now known as the "propeller belts" in the middle of Saturn's outermost dense ring, known as the A ring. The spaces were created by a new class of moonlets -- smaller than known moons, but larger than the particles in the rings -- that could clear the space immediately around them. Those moonlets, which were estimated to number in the millions, were not large enough to clear out their entire path around Saturn, as do the moons Pan and Daphnis.The new paper, led by Matthew Tiscareno, a Cassini imaging team associate based at Cornell University, Ithaca, N.Y., reports on a new cohort of larger and rarer moons in another part of the A ring farther out from Saturn. With propellers as much as hundreds of times as large as those previously described, these new objects have been tracked for as long as four years.The propeller features are up to several thousand kilometers (miles) long and several kilometers (miles) wide. The moons embedded in the ring appear to kick up ring material as high as 0.5 kilometers (1,600 feet) above and below the ring plane, which is well beyond the typical ring thickness of about 10 meters (30 feet). Cassini is too far away to see the moons amid the swirling ring material around them, but scientists estimate that they are about a kilometer (half a mile) in diameter because of the size of the propellers. »
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Better barriers can help levees withstand wave erosion
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 A new barrier design could protect reservoir levees from the erosive forces of wind-driven waves, according to studies by Agricultural Research Service (ARS) scientists and partners. These findings could help lower the maintenance costs for constructed ponds in the lower Mississippi Delta where levee repairs can average $3 per foot-and sometimes are needed just five years after a reservoir is built.Hydraulic engineer Daniel Wren, who works at the ARS Watershed Physical Processes Research Unit in Oxford, Miss., partnered with ARS hydraulic engineer Carlos Alonso (now retired) and University of Mississippi research associate Yavuz Ozeren for his research. The team gathered data about wind and wave dynamics from a 70-acre irrigation reservoir in Arkansas. Then they took their data into the lab and designed several wave barriers that they tested in a 63-foot-long wave flume.Their results indicated that a floating barrier held in place by two rows of pilings would provide the most effective embankment protection from wave action. Since the barrier was confined between the two rows of pilings, it could rise and fall with fluctuating water levels, unlike a barrier tethered to the bottom of the pond that might become submerged by rising water levels.The team found that a two-pipe barrier was able to dissipate 75 percent of wave energy before the waves washed against the levees. The waves lost some of their force when they broke against the first tube and then lost even more energy as they broke against the second tube. The engineers also found that bundling several lengths of smaller tubing together to obtain an optimal diameter for the floating barrier was less expensive than purchasing one tube with a larger diameter. »
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Super-high pressures used to create super battery: 'Most condensed form of energy storage outside of nuclear energy'
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 The world's biggest Roman candle has got nothing on this.Using super-high pressures similar to those found deep in the Earth or on a giant planet, Washington State University researchers have created a compact, never-before-seen material capable of storing vast amounts of energy."If you think about it, it is the most condensed form of energy storage outside of nuclear energy," says Choong-Shik Yoo, a WSU chemistry professor and lead author of results published in the journal Nature Chemistry.The research is basic science, but Yoo says it shows it is possible to store mechanical energy into the chemical energy of a material with such strong chemical bonds. Possible future applications include creating a new class of energetic materials or fuels, an energy storage device, super-oxidizing materials for destroying chemical and biological agents, and high-temperature superconductors.The researchers created the material on the Pullman campus in a diamond anvil cell, a small, two-inch by three-inch-diameter device capable of producing extremely high pressures in a small space. The cell contained xenon difluoride (XeF2), a white crystal used to etch silicon conductors, squeezed between two small diamond anvils. »
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Science historian cracks the 'Plato code'
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 Plato was the Einstein of Greece's Golden Age and his work founded Western culture and science. Dr Jay Kennedy's findings are set to revolutionise the history of the origins of Western thought.Dr Kennedy, whose findings are published in the leading US journal Apeiron, reveals that Plato used a regular pattern of symbols, inherited from the ancient followers of Pythagoras, to give his books a musical structure. A century earlier, Pythagoras had declared that the planets and stars made an inaudible music, a 'harmony of the spheres'. Plato imitated this hidden music in his books.The hidden codes show that Plato anticipated the Scientific Revolution 2,000 years before Isaac Newton, discovering its most important idea -- the book of nature is written in the language of mathematics. The decoded messages also open up a surprising way to unite science and religion. The awe and beauty we feel in nature, Plato says, shows that it is divine; discovering the scientific order of nature is getting closer to God. This could transform today's culture wars between science and religion."Plato's books played a major role in founding Western culture but they are mysterious and end in riddles," Dr Kennedy, at Manchester's Faculty of Life Sciences explains. »
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Relying on origami techniques, researchers show programmable matter folding into a boat- or plane-shape
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 "More than meets the eye" may soon become more than just a tagline for a line of popular robotic toys.Researchers at Harvard and MIT have reshaped the landscape of programmable matter by devising self-folding sheets that rely on the ancient art of origami.Called programmable matter by folding, the team demonstrated how a single thin sheet composed of interconnected triangular sections could transform itself into a boat- or plane-shape -- all without the help of skilled fingers.Published in the online Early Edition of the Proceedings of the National Academy of Sciences (PNAS) during the week of June 28, lead authors Robert Wood, associate professor of electrical engineering at the Harvard School of Engineering and Applied Sciences (SEAS) and a core faculty member of the Wyss Institute for Biologically Inspired Engineering, and Daniela Rus, a professor in the Electrical Engineering and Computer Science department at MIT and co-director of the CSAIL Center for Robotics, envision creating "smart" cups that could adjust based upon the amount of liquid needed or even a "Swiss army knife" that could form into tools ranging from wrenches to tripods. »
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'Quantum computer' a stage closer with silicon breakthrough
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 The remarkable ability of an electron to exist in two places at once has been controlled in the most common electronic material -- silicon -- for the first time. The research findings -- published in Nature by a UK-Dutch team from the University of Surrey, UCL (University College) London, Heriot-Watt University in Edinburgh, and the FOM Institute for Plasma Physics near Utrecht -- marks a significant step towards the making of an affordable "quantum computer."According to the research paper, the scientists have created a simple version of Schrodinger's cat -- which is paradoxically simultaneously both dead and alive -- in the cheap and simple material out of which ordinary computer chips are made."This is a real breakthrough for modern electronics and has huge potential for the future," explained Professor Ben Murdin, Photonics Group Leader at the University of Surrey. "Lasers have had an ever increasing impact on technology, especially for the transmission of processed information between computers, and this development illustrates their potential power for processing information inside the computer itself. In our case we used a far-infrared, very short, high intensity pulse from the Dutch FELIX laser to put an electron orbiting within silicon into two states at once -- a so-called quantum superposition state. We then demonstrated that the superposition state could be controlled so that the electrons emit a burst of light at a well-defined time after the superposition was created. The burst of light is called a photon echo; and its observation proved we have full control over the quantum state of the atoms."And the development of a silicon based "quantum computer" may be only just over the horizon. "Quantum computers can solve some problems much more efficiently than conventional computers -- and they will be particularly useful for security because they can quickly crack existing codes and create un-crackable codes," Professor Murdin continued. "The next generation of devices must make use of these superpositions to do quantum computations. Crucially our work shows that some of the quantum engineering already demonstrated by atomic physicists in very sophisticated instruments called cold atom traps, can be implemented in the type of silicon chip used in making the much more common transistor." »
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New method for producing graphene paves way for mass production of nanomaterial
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 Researchers at Rensselaer Polytechnic Institute have developed a simple new method for producing large quantities of the promising nanomaterial graphene. The new technique works at room temperature, needs little processing, and paves the way for cost-effective mass production of graphene.An atom-thick sheet of carbon arranged in a honeycomb structure, graphene has unique mechanical and electrical properties and is considered a potential heir to copper and silicon as the fundamental building block of nanoelectronics. Since graphene's discovery in 2004, researchers have been searching for an easy method to produce it in bulk quantities.A team of interdisciplinary researchers, led by Swastik Kar, research assistant professor in the Department of Physics, Applied Physics, and Astronomy at Rensselaer, has brought science a step closer to realizing this important goal. By submerging graphite in a mixture of dilute organic acid, alcohol, and water, and then exposing it to ultrasonic sound, the team discovered that the acid works as a "molecular wedge, " which separates sheets of graphene from the parent graphite. The process results in the creation of large quantities of undamaged, high-quality graphene dispersed in water. Kar and team then used the graphene to build chemical sensors and ultracapacitors."There are other known techniques for fabricating graphene, but our process is advantageous for mass production as it is low cost, performed at room temperature, devoid of any harsh chemicals, and thus is friendly to a number of technologies where temperature and environmental limitations exist," Kar said. "The process does not need any controlled environment chambers, which enhances its simplicity without compromising its scalability. This simplicity enabled us to directly demonstrate high-performance applications related to environmental sensing and energy storage, which have become issues of global importance." »
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Ocean stirring and plankton patchiness revealed by computer simulation
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 Computer simulations performed by researchers at the National Oceanography Centre and the University of Glasgow show how oceanic stirring and mixing influence the formation and dynamics of plankton patches in the upper ocean.Tiny free-floating marine plants called phytoplankton live in vast numbers in the sunlit upper ocean. Through the process of photosynthesis, they build carbon compounds such as sugars starting with just water and carbon dioxide, which is thereby drawn down from the atmosphere.Phytoplankton also need nutrients such as phosphate and iron, shortage of which can limit their population growth. They are also preyed upon by tiny planktonic animals called zooplankton."Interactions between phytoplankton, nutrients, zooplankton and the physical environment lead to complex dynamics, which we seek to understand using computer models," explained Emma Guirey, whose work on the problem was done as part of her PhD studies. "These complex dynamics can produce the patchiness of phytoplankton at the ocean surface that is invariably seen in satellite images and observed at sea during research cruises."Guirey and her colleagues applied the methods of synchronisation theory -- previously used to explain such phenomena as the co-ordinated flashing of fireflies along whole riverbanks. Initially they studied the balance between localised increases in phytoplankton populations and small-scale mixing, such as that due to breaking waves, in creating patches. Patchiness was found to persist despite the mixing which might be expected to smooth out the patches by blending them together. »
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Scientists call for a new strategy for polar ocean observation
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 In a report published in Science, a team of oceanographers, including MBL (Marine Biological Laboratory) Ecosystems Center director Hugh Ducklow, outline a polar ocean observation strategy they say will revolutionize scientists' understanding of marine ecosystem response to climate change. The approach, which calls for the use of a suite of automated technologies that complement traditional data collection, could serve as a model for marine ecosystems worldwide and help form the foundation for a comprehensive polar ocean observation system.The complexity of marine food webs and the "chronic under-sampling" of the world's oceans present major constraints to predicting the future of and optimally managing and protecting marine resources. "We know more about Venus than we do about the Earth's oceans," says Ducklow. "We need an ocean observation system analogous to meteorological monitoring for weather forecasting, but it's harder to do in the ocean."In polar oceans in particular, including the Western Antarctic Peninsula (WAP) where Ducklow and his colleagues conduct research as part of the NSF's Long-Term Ecological Research project at Palmer Station, high operation costs and harsh conditions restrict the coverage provided by research ships, where much of the data on this ecosystem is collected. To overcome these hurdles, oceanographers around the world have been developing technologies to complement traditional data collection by research ships. The coordinated use of these technologies will enable sustained observations throughout the year in the polar oceans and could form the foundation for a comprehensive observation strategy the team says. »
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Using carbon nanotubes in lithium batteries can dramatically improve energy capacity
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 Batteries might gain a boost in power capacity as a result of a new finding from researchers at MIT. They found that using carbon nanotubes for one of the battery's electrodes produced a significant increase -- up to tenfold -- in the amount of power it could deliver from a given weight of material, compared to a conventional lithium-ion battery. Such electrodes might find applications in small portable devices, and with further research might also lead to improved batteries for larger, more power-hungry applications.To produce the powerful new electrode material, the team used a layer-by-layer fabrication method, in which a base material is alternately dipped in solutions containing carbon nanotubes that have been treated with simple organic compounds that give them either a positive or negative net charge. When these layers are alternated on a surface, they bond tightly together because of the complementary charges, making a stable and durable film.The findings, by a team led by Associate Professor of Mechanical Engineering and Materials Science and Engineering Yang Shao-Horn, in collaboration with Bayer Chair Professor of Chemical Engineering Paula Hammond, are reported in a paper published June 20 in the journal Nature Nanotechnology. The lead authors are chemical engineering student Seung Woo Lee PhD '10 and postdoctoral researcher Naoaki Yabuuchi.Batteries, such as the lithium-ion batteries widely used in portable electronics, are made up of three basic components: two electrodes (called the anode, or negative electrode, and the cathode, or positive electrode) separated by an electrolyte, an electrically conductive material through which charged particles, or ions, can move easily. When these batteries are in use, positively charged lithium ions travel across the electrolyte to the cathode, producing an electric current; when they are recharged, an external current causes these ions to move the opposite way, so they become embedded in the spaces in the porous material of the anode. »
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