Low-Velocity Impacts on Targets Containing Embedded Carbon Nanotubes

by J. A. Carmona et al. arXiv.org E-print Archive, 29 Mar 2006 A one stage Light Gas Gun was employed to test the shielding capabilities of tiles composed of four different laminated nanotube combinations. These target tiles were named CSNEAT1, CSCNT1, HYCNTUT1 and HYCNTT1. For calibration purposes, a 3003- aluminum plate was also impacted and the craters formed on the various composition tiles compared. Read more

Memory Effects and Scaling Properties of Traffic Flows

by B.-S. Skagerstam & A. Hansen arXiv.org E-print Archive, 29 Mar 2006 Traffic flows are studied in terms of their noise of sound, which is an easily accessible experimental quantity. The sound noise data is studied making use of scaling properties of wavelet transforms and Hurst exponents are extracted. The scaling behavior is used to characterize the traffic flows in terms of scaling properties of the memory function in Mori-Lee stochastic differential equations. The results obtained provides for a new theoretical as well as experimental framework to characterize the large-time behavior of traffic flows. The present paper outlines the procedure by making use of one-lane computer simulations as well as sound-data measurements from a real two-lane traffic flow. We find the presence of conventional diffusion as well as 1/f-noise in real traffic flows at large time scales. Read more

Everlasting Power

by Caroline Williams New Scientist, 25 Mar 2006 "It looked like a slug moving along the lab bench," says Jeffrey Cheung, a materials scientist at Rockwell Scientific in Los Angeles. "My first reaction was -- oh my goodness someone forgot to turn off the sprinkler outside, and this thing has crawled into the lab. The strange thing was, when I moved to the right or the left, it always followed my movements." Then he leaned over to take a closer look. To his surprise, the slug shot off the workbench and rocketed straight at his midriff. That day, Cheung had been doing some experiments using a commercial ferrofluid. As fate would have it, he made two crucial errors. First he lost a bar magnet, which he had borrowed from a colleague for the experiment. Then he spilt a beakerful of the fluid over his lab bench, leaving it covered with a thick layer of reddish-brown goo. Read more

Robust Morphing Materials Take the Strain

by Will Knight NewScientist.com, 24 Mar 2006 Helicopter blades that change shape in mid-spin could be developed using a novel morphing material that works even under extreme stress and strain, researchers say. A sturdy material that changes shape by "recharging" like a lithium ion battery, is being developed by a team of material scientists at MIT, the Swiss Federal Institute of Technology in Switzerland, and the University of Karlsruhe in Germany. Read more

Chip Ramps Up Neuron-to-Computer Communication

by Tom Simonite NewScientist.com, 27 Mar 2006 A specialised microchip that could communicate with thousands of individual brain cells has been developed by European scientists. The device will help researchers examine the workings of interconnected brain cells, and might one day enable them to develop computers that use live neurons for memory. Read more

High-Performance High-Tc Superconducting Wires

by S. Kang et al. Science, 31 Mar 2006 We demonstrated short segments of a superconducting wire that meets or exceeds performance requirements for many large-scale applications of high-temperature superconducting materials, especially those requiring a high supercurrent and/or a high engineering critical current density in applied magnetic fields. The performance requirements for these varied applications were met in 3-micrometer-thick YBa₂Cu₃O_7- films epitaxially grown via pulsed laser ablation on rolling assisted biaxially textured substrates. Enhancements of the critical current in self-field as well as excellent retention of this current in high applied magnetic fields were achieved in the thick films via incorporation of a periodic array of extended columnar defects, composed of self-aligned nanodots of nonsuperconducting material extending through the entire thickness of the film. These columnar defects are highly effective in pinning the superconducting vortices or flux lines, thereby resulting in the substantially enhanced performance of this wire. Read more

March of the Qubits

by Dan Cho New Scientist, 25 Mar 2006 They said it couldn't be done. They said it would never be practical. They were wrong, says David Deutsch. He is referring to the quest to build a quantum computer. This machine would exploit the weird properties of quantum mechanics to perform tasks millions of times faster than today's most powerful supercomputers. Such a device -- if we can build one -- would overturn the field of cryptography and revolutionise the computer industry. Yet despite this glittering prize, researchers have so far only coaxed quantum systems into solving mathematics problems that children can do in their heads. Read more

Stealth Underwater Craft Targets Minefields

by Mark Peplow news@nature.com, 23 Mar 2006 An underwater craft that can seek out and destroy mines has been unveiled. The sub, dubbed Talisman, relies on computer software that allows it to complete its mission without being guided by an operator. Read more

Shape Memory in Spider Draglines

by Olivier Emile, Albert Le Floch, & Fritz Vollrath Nature, 30 Mar 2006 The ductility and strength of spider draglines means that they outperform the best synthetic fibres, but surprisingly little is known about the torsional properties of this remarkable filament. Unlike a mountain climber swinging from a rope, a spider suspended from its silk thread hardly ever twists. Here we show that a spider dragline has a torsional shape 'memory' in that it can reversibly and totally recover its initial form without any external stimulus; its observed relaxation dynamics indicate that these biological molecules have successively different torsional constants. Read more

Ab Initio Determination of Solid-State Nanostructure

by P. Juhás et al. Nature, 30 Mar 2006 Advances in materials science and molecular biology followed rapidly from the ability to characterize atomic structure using single crystals. Structure determination is more difficult if single crystals are not available. Many complex inorganic materials that are of interest in nanotechnology have no periodic long-range order and so their structures cannot be solved using crystallographic methods. Here we demonstrate that ab initio structure solution of these nanostructured materials is feasible using diffraction data in combination with distance geometry methods. Precise, sub-ångström resolution distance data are experimentally available from the atomic pair distribution function (PDF). Current PDF analysis consists of structure refinement from reasonable initial structure guesses and it is not clear, a priori, that sufficient information exists in the PDF to obtain a unique structural solution. Here we present and validate two algorithms for structure reconstruction from precise unassigned interatomic distances for a range of clusters. We then apply the algorithms to find a unique, ab initio, structural solution for C₆₀ from PDF data alone. This opens the door to sub-ångström resolution structure solution of nanomaterials, even when crystallographic methods fail. Read more

Quantum Mechanics in the Brain

by Christof Koch & Klaus Hepp Nature, 30 Mar 2006 The relation between quantum mechanics and higher brain functions, including consciousness, is often discussed, but is far from being understood. Physicists, ignorant of modern neurobiology, are tempted to assume a formal or even dualistic view of the mind-brain problem. Meanwhile, cognitive neuroscientists and neurobiologists consider the quantum world to be irrelevant to their concerns and therefore do not attempt to understand its concepts. What can we confidently state about the current relationship between these two fields of scientific inquiry? Read more

Photodiodes Advance Quantum Communications

by Mark Itzler fibers.org News, 29 Mar 2006 The advent of public network encryption has revolutionized secure information exchange. This modern method, based on algorithms, involves one party providing a public key that allows any other party to encrypt a message, but decryption can only be performed with a separate, private key held by the first party. This scheme does have a weakness, though, because it relies on computational complexity. Although breaking the key is exceedingly difficult today, this data encryption approach could be compromised in the foreseeable future through advances in computational power and the mathematics associated with code breaking. Princeton Lightwave has commercialized a single-photon avalanche photodiode that is targeting quantum cryptography applications, and it could provide uncrackable communications. Read more

Channel Plasmon Subwavelength Waveguide Components

by Sergey I. Bozhevolnyi et al. Nature, 23 Mar 2006 Photonic components are superior to electronic ones in terms of operational bandwidth, but the diffraction limit of light poses a significant challenge to the miniaturization and high-density integration of optical circuits. The main approach to circumvent this problem is to exploit the hybrid nature of surface plasmon polaritons (SPPs), which are light waves coupled to free electron oscillations in a metal that can be laterally confined below the diffraction limit using subwavelength metal structures. However, the simultaneous realization of strong confinement and a propagation loss sufficiently low for practical applications has long been out of reach. Channel SPP modes -- channel plasmon polaritons (CPPs) -- are electromagnetic waves that are bound to and propagate along the bottom of V-shaped grooves milled in a metal film. They are expected to exhibit useful subwavelength confinement, relatively low propagation loss, single-mode operation and efficient transmission around sharp bends. Our previous experiments showed that CPPs do exist and that they propagate over tens of micrometres along straight subwavelength grooves. Here we report the design, fabrication and characterization of CPP-based subwavelength waveguide components operating at telecom wavelengths: Y-splitters, Mach-Zehnder interferometers and waveguide-ring resonators. We demonstrate that CPP guides can indeed be used for large-angle bending and splitting of radiation, thereby enabling the realization of ultracompact plasmonic components and paving the way for a new class of integrated optical circuits. Read more

Technology for Creation of Antiwear Polymer Films

Virginia Tech Public Release, 29 Mar 2006 When Michael Furey, professor of mechanical and biomedical engineering, at Virginia Tech, met Czeslaw Kajdas, then with the Radom Technical University in Poland, at a conference in Europe in 1981, they had differing views on how to form polymer films on surfaces to reduce wear. The result of their eventual collaboration has been fundamental discoveries in surface chemistry and dozens of compounds that reduced wear in metals, advanced alloys, and ceramics. These include ashless antiwear additives for fuels, such as for diesel, jet, and two-cycle gasoline fuels; lubricants for automotive and industrial applications; and a variety of applications in which environmental concerns are important. Read more

Rising to the Challenge of Managing Bandwidth

EU Information Society Technologies Public Release, 29 Mar 2006 The EVEREST project developed and tested advanced algorithms to provide mobile operators with enhanced Radio Resource Management techniques aimed at reducing the risk of communications bottlenecks at a time when mobile devices are increasingly being used for much more than just voice calls. Email, video conferencing, live television and streaming music, together with a range of other emerging mobile services and applications all increase the pressure on limited network resources. Read more

Engineers Building Erasible Detectors, Nanobrushes and DNA Highrises

Duke University Public Release, 29 Mar 2006 A Duke University engineering group is doing pioneering work at very diminutive dimensions. Their basic studies could lead to genetically engineered proteins that can form erasable chemical detectors; self-grown forests of molecular "bottlebrushes" that keep themselves contamination-free; and auto-assembled DNA "towers" that could become anchors for the tiniest of devices. Read more

New Coating Protects Steel and Superalloys

Pacific Northwest National Laboratory Public Release, 22 Mar 2006 Researchers at Pacific Northwest National Laboratory have developed a new ceramic-based coating for steel and superalloys that prevents corrosion, oxidation, carburization and sulfidation that commonly occur in gas, liquid, steam and other hostile environments. Read more

Magnetism Shepherds Microlenses to Excavate 'Nanocavities'

Duke University Public Release, 30 Mar 2006 A Duke University engineer is "herding" tiny lenses with magnetic ferrofluids, precisely aligning them so that they focus bursts of light to excavate patterns of cavities on surfaces. Such photolithographically produced "nanocavities" -- each only billionths of a meter across -- might serve as repositories for molecules engineered as chemical detectors, said Benjamin Yellen, an assistant professor of mechanical engineering and materials science at Duke's Pratt School of Engineering. Alternatively, he said, ringlike structures created via a similar technique might be useful for fabricating magnetic data storage elements. Read more

Submicron Gap Capacitor for Measurement of Breakdown Voltage in Air

by Emmanouel Hourdakis, Brian J. Simonds, & Neil M. Zimmerman Review of Scientific Instruments, 24 Mar 2006 (online) We have developed a new method for measuring the value of breakdown voltage in air for electrode separations from 400 nm to 45 µm. The electrodes used were thin film Au lines evaporated on sapphire. The resulting capacitors had an area of 80×80 µm². We demonstrate the ability to deduce the value of the separation of the plates by the value of the capacitance. The data acquired with this method do not agree with Paschen's law for electrode separations below 10 µm, as expected from previous experiments. Amongst the improvements of our method are the measurement of plate separation and the very small surface roughness. Read more

Drone Demand Surges on the Front Lines

CNN News, 29 Mar 2006 Piloted remotely from a Nevada air base half a world away or by soldiers on the scene, unmanned aircraft have become so indispensable in Iraq and in the war on terror that by next year the U.S. could be spending nearly seven times more on the vehicles than it did before the 9/11 attacks. The aircraft were heavily used after last month's bombing of a mosque in Samarra, Iraq, highlighting how prevalent they have become for a military thirsty for vehicles that can drop bombs or hover over targets without risking pilots' lives. Read more

Scientists Recreate the 1906 San Francisco Quake

CNN News, 29 Mar 2006 Scientists on Tuesday unveiled what they described as the most detailed computer simulations of the catastrophic 1906 San Francisco earthquake. The virtual models use three-dimensional geologic maps constructed by the U.S. Geological Survey last year to recreate a comprehensive portrait of how hard and how long the ground shook. Read more

Wind Power 'Ahead of Predictions'

BBC News, 27 Mar 2006 Onshore wind farms will provide about 5% of Britain's electricity by 2010, according to the British Wind Energy Association. In a new report, it says turbines are being installed faster than predicted. If this is correct, onshore wind farms will take the government halfway to its target of generating 10% of electricity from renewable sources by 2010. Read more

Home Power Plan 'Disappointment'

by Richard Black BBC News, 29 Mar 2006 There has been a lukewarm reaction to the government's strategy on microgeneration, launched on Wednesday. The strategy aims to create conditions under which household or community generation of electricity becomes "a realistic alternative". While some industry figures have welcomed the strategy, others say it is short on concrete action and funding. Read more

Georgia Researchers Develop Hybrid Network

TechWorld, 24 Mar 2006 Researchers at the Georgia Institute of Technology are developing a network technology that promises increased access to high-speed Internet service. The technology would carry both wired and wireless signals on the same fiber-optic cable, allowing both kinds of service in facilities such as conference centers and offices with just one set of wiring. The signal would be split to accommodate connections through wall outlets as well as through wireless access points. Users could connect through either channel and achieve access speeds of up to 2.5 Gbps. The network would also allow so-called wave division multiplexing, which would divide the connection into as many as 32 channels, each capable of the same 2.5 Gbps speed. Read more

Automatic Guided Vehicle Loads Trailers Unattended

ThomasNet Industrial Newsroom, 21 Mar 2006 Designed for 24/7 trailer loading and warehousing, SmartLoader provides unmanned solution that adapts to various trailer sizes and skew angles without manual modification. An inertial guidance system relies upon transponders embedded in the floor that identify its exact location. The vehicle maneuvers around a warehouse utilizing a Vehicle Control Computer, which maintains the intended path and performs required tasks, and integrates with WMS for real-time control. Read more

Using MEMS for Adaptive Optics

by Sergio Restaino & Jonathan Andrews SPIE Newsroom, accessed 29 Mar 2006 Microelectromechanical devices have dramatically reduced the size and cost of adaptive optics and made it possible to construct portable systems that can improve the resolution of any telescope.

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DOT Funding Opportunity - Buried Mine Sensing from an Unmanned Air Vehicle

The Office of Naval Research seeks white papers describing innovative technology concepts to provide standoff detection or indicators of buried mines, mine lines or minefields from an unmanned air vehicle. Concepts are required to detect mines buried on the beach and in the surf zone. The environment includes the beach which can alternate between dry and wet conditions due to tides, and the surf zone which extends from the beach out to a water depth of 5 meters. The targets include buried anti-tank and anti-invasion mines. Concepts may include a single sensor technology or multiple sensor technologies to cover different portions of the environment with fusion of the results and on-board real-time processing of imagery and detections. The effort will include basic concept investigations and experiments leading to the development of hardware for a demonstration of the concepts from a manned aircraft. The intention is to initiate new research efforts in FY 2007 with candidate concepts demonstrated in FY 2009 or earlier.

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Net Writing New Chapter for Science Journals

by Andrew Kantor USATODAY.com, 23 Mar 2006 While the Internet is certainly affecting how the mainstream media works, there's another area that the anyone's-a-publisher paradigm is affecting: the world of scientific journals. The American Chemical Society just laid off a bunch of people who put its journals together, outsourcing the operation to the company that prints them. The move is indicative of the pressure scientific organizations are feeling as a new generation of scientists enter the lab having grown up in an Internet world. Read more

General Strategies for Nanoparticle Dispersion

by Michael E. Mackay et al. Science, 24 Mar 2006 Traditionally the dispersion of particles in polymeric materials has proven difficult and frequently results in phase separation and agglomeration. We show that thermodynamically stable dispersion of nanoparticles into a polymeric liquid is enhanced for systems where the radius of gyration of the linear polymer is greater than the radius of the nanoparticle. Dispersed nanoparticles swell the linear polymer chains, resulting in a polymer radius of gyration that grows with the nanoparticle volume fraction. It is proposed that this entropically unfavorable process is offset by an enthalpy gain due to an increase in molecular contacts at dispersed nanoparticle surfaces as compared with the surfaces of phase-separated nanoparticles. Even when the dispersed state is thermodynamically stable, it may be inaccessible unless the correct processing strategy is adopted, which is particularly important for the case of fullerene dispersion into linear polymers. Read more

An Integrated Logic Circuit Assembled on a Single Carbon Nanotube

by Zhihong Chen et al. Science, 24 Mar 2006 Single-walled carbon nanotubes (SWCNTs) have been shown to exhibit excellent electrical properties, such as ballistic transport over several hundred nanometers at room temperature. Field-effect transistors (FETs) made from individual tubes show dc performance specifications rivaling those of state-of-the-art silicon devices. An important next step is the fabrication of integrated circuits on SWCNTs to study the high-frequency ac capabilities of SWCNTs. We built a five-stage ring oscillator that comprises, in total, 12 FETs side by side along the length of an individual carbon nanotube. A complementary metal-oxide semiconductor-type architecture was achieved by adjusting the gate work functions of the individual p-type and n-type FETs used. Read more

NSF Program Solicitation - Defining the Large-Scale Infrastructure Needs of the Computing Research Community

Program Solicitation NSF 06-551 The availability of state-of-the-art research infrastructure is essential to advances in all science and engineering fields. For many years, NSF has supported the development and deployment of research instrumentation and facilities. Shared-use facilities in particular, including those funded through NSF's Major Research Equipment and Facilities Construction Account, have been instrumental in allowing science and engineering communities to explore compelling research "grand challenges." With emerging systems-level challenges and opportunities in computer science and engineering, the time is right for the computing research community to identify the large-scale research infrastructure needs critical, not only to advances in the field, but to US competitiveness in IT overall. Read more

Intel Discloses Technologies to Make the Internet More Personal and Mobile

PhysOrg.com, 8 Mar 2006 As consumer and business demand for Internet applications on the go continues, Intel disclosed details of the next-generation Centrino mobile technology-based platform, as well as a single chip Wi-Fi/WiMAX radio and an Intel-branded mobile WiMAX PCMCIA card. They also provided details about the next generation dual-core mobile processor based on Intel’s Core microarchitecture and Intel’s next-generation applications processor for handheld devices. These innovations are designed help make the Internet a more personal and mobile experience for people worldwide. Read more

A Two-Way Street to Science's Future

by Ian Foster Nature, 23 Mar 2006 To view the relationship between computing and science as a one-way street is mostly untrue today, and will be even less true by 2020. Read more

Can Computers Help to Explain Biology?

by Roger Brent & Jehoshua Bruck Nature, 23 Mar 2006 The road leading from computer formalisms to explaining biological function will be difficult, but three hopeful paths could take us closer to this goal. Read more

Everything, Everywhere

by Declan Butler Nature, 23 Mar 2006 Tiny computers that constantly monitor ecosystems, buildings and even human bodies could turn science on its head. Read more

Champing at the Bits

by Philip Ball Nature, 23 Mar 2006 Despite some remaining hurdles, the mind-bending and frankly weird world of quantum computers is surprisingly close. Here's how these unusual machines will earn their keep. Read more

Pipe Network to be Mapped in 3D

by Jonathan Amos BBC News, 22 Mar 2006 The maze of pipes and cables that snake beneath the UK's streets are to be mapped in a £2.2m pilot project. An intimate knowledge of this tubular underworld is expected to help reduce the number of holes that need to be dug by utilities, and cut traffic jams. Read more

New Light Detector Could Allow Broadband in Space

by Ker Than USATODAY.com, 20 Mar 2006 Researchers at the Massachusetts Institute for Technology have developed a tiny light detector that could one day boost interplanetary communications to broadband speeds. The work could permit the transmission of color video between astronauts and satellites and scientists on Earth across interplanetary distances, something that is not practical with current technologies. Read more

Nano Neuro Knitting

by Rutledge G. Ellis-Behnke Proceedings of the National Academy of Sciences, 20 Mar 2006 (online) Nanotechnology is often associated with materials fabrication, microelectronics, and microfluidics. Until now, the use of nanotechnology and molecular self assembly in biomedicine to repair injured brain structures has not been explored. To achieve axonal regeneration after injury in the CNS, several formidable barriers must be overcome, such as scar tissue formation after tissue injury, gaps in nervous tissue formed during phagocytosis of dying cells after injury, and the failure of many adult neurons to initiate axonal extension. Using the mammalian visual system as a model, we report that a designed self-assembling peptide nanofiber scaffold creates a permissive environment for axons not only to regenerate through the site of an acute injury but also to knit the brain tissue together. In experiments using a severed optic tract in the hamster, we show that regenerated axons reconnect to target tissues with sufficient density to promote functional return of vision, as evidenced by visually elicited orienting behavior. The peptide nanofiber scaffold not only represents a previously undiscovered nanobiomedical technology for tissue repair and restoration but also raises the possibility of effective treatment of CNS and other tissue or organ trauma. Read more

Microstructured Optical Fibers as High-Pressure Microfluidic Reactors

by Pier J. A. Sazio et al. Science, 17 Mar 2006 Deposition of semiconductors and metals from chemical precursors onto planar substrates is a well-developed science and technology for microelectronics. Optical fibers are an established platform for both communications technology and fundamental research in photonics. Here, we describe a hybrid technology that integrates key aspects of both engineering disciplines, demonstrating the fabrication of tubes, solid nanowires, coaxial heterojunctions, and longitudinally patterned structures composed of metals, single-crystal semiconductors, and polycrystalline elemental or compound semiconductors within microstructured silica optical fibers. Because the optical fibers are constructed and the functional materials are chemically deposited in distinct and independent steps, the full design flexibilities of both platforms can now be exploited simultaneously for fiber-integrated optoelectronic materials and devices. Read more

Statistics of Pressure Fluctuations in Decaying, Isotropic Turbulence

by Chirag Kalelkar arXiv.org E-print Archive, 20 Mar 2006 We present results from a systematic direct-numerical simulation study of pressure fluctuations in an unforced, incompressible, homogeneous, and isotropic, three-dimensional turbulent fluid. At cascade completion, isosurfaces of low pressure are found to be organised as slender filaments, whereas the predominant isostructures appear sheet-like. We exhibit several new results, including plots of probability distributions of the spatial pressure-difference, the pressure-gradient norm, and the eigenvalues of the pressure-hessian tensor. Plots of the temporal evolution of the mean pressure-gradient norm, and the mean eigenvalues of the pressure-hessian tensor are also exhibited. We find the statistically preferred orientations between the eigenvectors of the pressure-hessian tensor, the pressure-gradient, the eigenvectors of the strain-rate tensor, the vorticity, and the velocity. Statistical properties of the non-local part of the pressure-hessian tensor are also exhibited, for the first time. We present numerical tests of some conjectures of Ohkitani and Kishiba concerning the pressure-hessian and the strain-rate tensors, for the unforced, incompressible, three-dimensional Euler equations. Read more

Vulnerability of Weighted Networks

by Luca Dall'Asta et al. arXiv.org E-print Archive, 20 Mar 2006 In real networks complex topological features are often associated with a diversity of interactions as measured by the weights of the links. Moreover, spatial constraints may as well play an important role, resulting in a complex interplay between topology, weight, and geography. In order to study the vulnerability of such networks to intentional attacks, these attributes must be therefore considered along with the topological quantities. In order to tackle this issue, we consider the case of the world-wide airport network, which is a weighted heterogeneous network whose evolution and structure are influenced by traffic and geographical constraints. We first characterize relevant topological and weighted centrality measures and then use these quantities as selection criteria for the removal of vertices. We consider different attack strategies and different measures of the damage achieved in the network. The analysis of weighted properties shows that centrality driven attacks are capable to shatter the network's communication or transport properties even at very low level of damage in the connectivity pattern. The inclusion of weight and traffic therefore provides evidence for the extreme vulnerability of complex networks to any targeted strategy and need to be considered as key features in the finding and development of defensive strategies. Read more

Design Flaw Led to New Orleans Levee Breach

New Scientist, 18 Mar 2006 We now know how it happened, but whether it could have been prevented is still hotly disputed. The US Army Corps of Engineers has acknowledged for the first time that the New Orleans 17th Street Canal levee was breached during hurricane Katrina because of a failure in the system, rather than because the storm exceeded the levee's design specification. On 10 March, the corps released an interim report saying the levee split in two when its steel-supported concrete walls tilted. That, and a weak layer of clay in the soil near the edge of the levee, caused a 60-metre-long portion of the barrier to slide forward and break away. However, Ivor van Heerden of the Louisiana State University Hurricane Center in Baton Rouge insists that the corps knew about the weak layer of soil, having discovered it in borehole samples taken in 1982. Other scientists say the sliding action of the levee was also documented in the 1980s, after tests carried out by corps's engineers.

Fuel-Powered Artificial Muscles

by Von Howard Ebron et al. Science, 17 Mar 2006 Artificial muscles and electric motors found in autonomous robots and prosthetic limbs are typically battery-powered, which severely restricts the duration of their performance and can necessitate long inactivity during battery recharge. To help solve these problems, we demonstrated two types of artificial muscles that convert the chemical energy of high-energy-density fuels to mechanical energy. The first type stores electrical charge and uses changes in stored charge for mechanical actuation. In contrast with electrically powered electrochemical muscles, only half of the actuator cycle is electrochemical. The second type of fuel-powered muscle provides a demonstrated actuator stroke and power density comparable to those of natural skeletal muscle and generated stresses that are over a hundred times higher. Read more

Remote-Controlled Implants

by Barry Fox NewScientist.com, 21 Mar 2006 Remember Fantastic Voyage, the 1966 sci-fi movie in which a medical team is miniaturised and injected into the body of a dying man aboard a tiny submarine? No one has yet shrunk a surgeon, but Lawrence Livermore National Laboratory has come up with the next best thing -- a way to remotely control implanted components from outside the body. Ear and retinal implants help restore hearing or sight by bypassing damaged cells and directly stimulating nerve ends with tiny electrodes. But the tricky part is getting the implant into place and in contact with the nerve endings. Livermore’s device consists of an implant attached to a silicone tube a few millimetres long. The tube has with gold particles on its tip and a current is passed wirelessly through these to create a patterned magnetic field, which can then be used to manoeuvre the implant remotely. The implants could be injected near the target site and moved around the patient’s head using an external electromagnet. When the implant is in position the gold particles should also work as electrodes to feed signals from the wires into the nerves. But what made Livermore stray away from their bread-and-butter weapons research and towards medicine? The clue in the patent is the reference to using the technology to assemble miniaturised weaponry. Read patent

Pseudowires Maximize Carrier Service Options

by Meghan Fuller fibers.org News, 13 Mar 2006 Pseudowires -- point-to-point virtual connections across a packet-switched network -- enable the transport of legacy services over an IP/Ethernet network. This feature, along with the other benefits of this new transport mechanism, is catching the carriers' attention. Read more

Arbitrary-Bandwidth Brillouin Slow Light in Optical Fibers

by Miguel González Herráez, Kwang Yong Song, & Luc Thévenaz Optics Express, February 2006 Brillouin slow light in optical fibers is a promising technique for the development of all-optical buffers to be used in optical routers. The main drawback of this technique up to now has been its narrow bandwidth, normally restricted to 35 MHz in conventional single-mode optical fibers. In this paper we demonstrate experimentally that Brillouin slow light with an arbitrary large bandwidth can be readily obtained in conventional optical fibers using a simple and inexpensive pump spectral broadening technique. In our experiments, we show the delaying of 2.7 ns pulses over slightly more than one pulse length with only some residual broadening (<25%) of the pulse width. We see no limit to extend this technique to the delaying of GHz-bandwidth signals. Read more

World's First Transparent Integrated Circuit Created

Oregon State University Public Release, 17 Mar 2006 Researchers at Oregon State University have created the world's first completely transparent integrated circuit from inorganic compounds, another major step forward for the rapidly evolving field of transparent electronics. Read more

Propulsion of Ripples on Glass by Ion Bombardment

by P. F. A. Alkemade Physical Review Letters, 17 Mar 2006 The propulsion of surface ripples on SiO₂ by an ion beam was investigated by in situ electron microscopy. The observed propagation of the ripples contradicts existing models for ion-beam-induced ripple development. A new model based on the Navier-Stokes relations for viscous flow in a thin layer is introduced. It includes inhomogeneous viscous flow, driven by spatial variations in the deposition of the energy of the ion beam. The model explains the observed reversed propagation. The hitherto unknown propulsion mechanism is important for understanding nanoscale pattern formation by ion bombardment. Read more

Materials Chemistry for Low-k Materials

by Benjamin D. Hatton et al. Materials Today, March 2006 The microelectronics industry is constantly trying to reinvent itself, to find new technological solutions to keep pace with the trend of increasing device densities in ultra-large-scale integrated circuits. Integral in this development has been the replacement of the conventional Al/SiO₂ metal and dielectric materials in multilevel interconnect structures. Higher-conductivity Cu has now successfully replaced Al interconnects, but there is still a need for new low dielectric constant (k) materials, as an interlayer dielectric. Read more

Flying without Wing Flaps and without a Pilot

University of Leicester Public Release, 21 Mar 2006 A revolutionary model plane has been developed as part of a £6.2m programme, involving engineers from the University of Leicester. The five-year programme is called FLAVIIR -- flapless air vehicle integrated industrial research -- and involves teams from Leicester, Liverpool, Nottingham, Southampton, Swansea, Warwick, York and London. Manchester University's Goldstein Aeronautical Research Laboratory developed the model aircraft and the programme is managed by Cranfield University. Read more

Nanoelectronics Roadmap Aims to Speed Commercialization

by Nicolas Mokhoff EE Times, 21 Mar 2006 The IEEE launched an Nanoelectronics Standards Roadmap initiative March 21 to forge industry standards for nanotechnology. The effort is designed to move nanoelectronics innovations from laboratory to the marketplace for applications ranging from communications, information technology, consumer products and optoelectronics. Read more

Chemists Work on Plastic Promise

by Jonathan Fildes BBC News, 20 Mar 2006 A new plastic that could rival silicon as the material of choice for some electronic devices has been developed. The invention could eventually slash the cost of flat panel screens and bring electronic paper into common use. The new material can also be laid down using simple printing techniques rather than the expensive and elaborate methods used to process silicon. Read more

Virus Used to Make Nanoparticles

BBC News, 19 Mar 2006 UK scientists from Norwich have used a plant virus to create nanotechnology building blocks. The virus, which infects black-eyed peas, was employed as a "scaffold" on to which other chemicals were attached. By linking iron-containing compounds to the virus's surface, the John Innes Centre team was able to create electronically active nanoparticles. Read more

Microprocessor IP Cores Battle Obsolescence

by John McHale Military & Aerospace Electronics, February 2006 Military designers of embedded systems see integrated circuits designed as intellectual-property cores as the solution to the obsolescence issue that has been the bane of users of commercial-off-the-shelf equipment for more than a decade. Read more

High-Speed Single-Cell Analysis on a Microchip

by Hywel Morgan et al. SPIE Newsroom, accessed 15 Mar 2006 A new microchip analyzes thousands of cells per minute in an enclosed microfluidic environment. Read more

Psychiatry's Shocking New Tools

by S. K. Moore IEEE Spectrum, March 2006 Electronic implants and electromagnetic pulses are picking up where psychoactive drugs have failed. Read more

New Microchips Shun Transistors

by John Hudson Wired News, 14 Feb 2006 As transistor-based microchips hit the limits of Moore's Law, a group of electrical engineers at the University of Notre Dame has fabricated a chip that uses nanoscale magnetic "islands" to juggle the ones and zeroes of binary code. Wolfgang Porod and his colleagues turned to the process of magnetic patterning to produce a new chip that uses arrays of separate magnetic domains. Each island maintains its own magnetic field. Because the chip has no wires, its device density and processing power may eventually be much higher than transistor-based devices. And it won't be nearly as power-hungry, which will translate to less heat emission and a cooler future for portable hardware like laptops. Read more

New Gallium Nitride Film Method Beats the Heat

PhysOrg.com, 21 Feb 2006 A team of Los Alamos National Laboratory scientists have developed a method for growing crystalline gallium nitride films at lower temperatures than industry standards. By eliminating the higher temperatures and harsh, reactive environments that currently limit the types of materials used as substrates, the discovery could greatly increase the use of crystalline gallium nitride films in optical-electronic devices, like blue LEDs and laser diodes, high-density optical data storage devices, flat panel displays and solid state lighting. Read more

Unsafe at Any Airspeed?

by Bill Strauss et al. IEEE Spectrum, Marhc 2006 Is it safe to use cell phones on airplanes? Phones, PDAs, laptops, DVD players, and game machines all emit radiation and have the potential to interfere with aircraft instrumentation. Yet a recent study found that passengers are using cell phones, on the average, at least once per flight, and sometimes during the especially critical flight phases of takeoff and landing. Read more

High Performance Architecture Examined

What is the future for processor and parallel computer architecture? The proceedings from the 2006 IEEE 12th International Symposium on High Performance Computer Architecture attempt to answer this question as well as many others. The proceedings cover a variety of the latest computing technological innovations including interconnect and network interface architectures and network processor architectures. Read more

Quantum Computer Solves Problem, Without Running

PhysOrg.com, 22 Feb 2006 By combining quantum computation and quantum interrogation, scientists at the University of Illinois at Urbana-Champaign have found an exotic way of determining an answer to an algorithm -- without ever running the algorithm. Read more

Study Says Chips in ID Tags Are Vulnerable to Viruses

by John Markoff New York Times, 15 Mar 2006 A group of European computer researchers have demonstrated that it is possible to insert a software virus into radio frequency identification tags, part of a microchip-based tracking technology in growing use in commercial and security applications. Read more

NSF Program Solicitation - Research and Evaluation on Education in Science and Engineering

The Division of Research, Evaluation and Communication in the Directorate for Education and Human Resources of the National Science Foundation supports basic and applied research and evaluation that enhances science, technology, engineering and mathematics learning and teaching. This solicitation calls for two types of proposals -- synthesis and empirical. Read more

NSF Program Solicitation - Nanotechnology Undergraduate Education

This solicitation aims at introducing nanoscale science, engineering, and technology through a variety of interdisciplinary approaches into undergraduate education. The focus is on nanoscale engineering education with relevance to devices and systems and/or on the social, economic, and ethical issues that surround nanotechnology.

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Solar Cell Developers Look Beyond Silicon

by Chappell Brown EE Times, 20 Feb 2006 A new slant on compound semiconductors has produced a high-efficiency photovoltaic process that might beat existing technologies in cost of production as well. Read more

Nanofuel Cells Provide Remote Power

by R. Colin Johnson EE Times, 20 Feb 2006 A researcher at Lawrence Berkeley National Laboratories has demonstrated a fuel cell measuring just 200 nanometers across that potentially can be integrated on-chip to supply power from a hydrogen reservoir for decades. Read more

Harvesting Energy into Lithium-Ion Batteries

by Erick O. Torres & Gabriel A. Rincón-Mora Power Management DesignLine, 14 Feb 2006 Modern portable micro-systems like biomedical implants and ad-hoc wireless transceiver micro-sensors continue to integrate more functions into smaller devices, which result in low energy levels and short operational lives. Researchers and industry alike are therefore considering harvesting energy from the surrounding environment as a means of offsetting this energy deficit. Read more

Call for Papers: Rural Electric Power Conference

The 2007 IEEE Rural Electric Power Conference is seeking papers submissions about the planning, design, construction, operation and analysis of electrical distribution systems, authors are encouraged to submit papers on topics such as computer application for utilities, power quality and reliability, and other related topics. The conference, geared toward the practicing utility engineer working for an electric utility, is scheduled to take place in Rapid City, South Dakota, USA from 6 to 8 May 2007. Paper submissions are due 15 September 2006. Read more

Good Computer Interfaces Respect the Real World

PhysOrg.com, 22 Feb 2006 Every time a person uses a computer -- a desktop, a cell phone or even a chip-enabled coffee maker -- the interaction is specified by an interface designer. These interfaces often fall short or even fail because designers overlook the physical nature of human beings and the real world. As computers become ubiquitous, designers must take everyday users into account from the beginning, prototyping extensively to stay attuned to human needs and capabilities. Read more

IEEE Wireless Communications Tackles VoWLAN

The February 2006 issue of IEEE Wireless Communications takes an in-depth look at voice over wireless local area networks (VoWLAN). The special issue aims to disseminate the state-of-the-art R&D results on VoWLAN, facilitate the deployment of VoWLAN, and bring together researchers from both academia and industry in networking, wireless communications, and mobile computing, with the goal of fostering interaction. Read more

Call for Papers: Intelligent Sensors

The editors of IEEE Sensors Journal need paper submissions for a special issue on intelligent sensors. The issue will focus on accuracy, adaptability, reliability, recalibration, information processing, data fusion and integration. Authors are encouraged to submit papers on all aspects of modeling, design, development, implementation, characterization, operation and application of intelligent sensors and sensor networks. The deadline for submission is 15 June 2006. Read more

Intelligent Transportation Papers Needed

The IEEE Pervasive Computing Magazine has announced a call for papers for a special issue on intelligent transportation. Authors are asked to submit articles describing the application of pervasive computing technologies, systems, and applications to vehicles, roads, and other transportation systems. Also encouraged are articles that discuss the security, privacy, social, and human-related issues of intelligent transportation, and case studies of experiences with existing pervasive technologies in use in transportation. Deadline for submission is 31 May 2006. Read more

Bacteria Turn Styrofoam into Biodegradable Plastic

by David Biello ScientificAmerican.com, 27 Feb 2006 Biologists at the University College Dublin in Ireland have found that a strain of Pseudomonas putida bacteria can exist quite happily on a diet of pure styrene oil -- the oil remnant of superheated Styrofoam -- and, in the process, turn the environmental problem into a useful, biodegradable plastic. Read more

Rebirth of the 1553 Databus

by John Keller Military & Aerospace Electronics, February 2006 The MIL-STD-1553 databus has been a reliable constant in a quickly changing landscape of military technology. Its proponents praise the ageing databus as one of the most reliable networks ever created. At the same time, however, the 1553's limited throughput-just 1 megabit per second-is widely seen as an information-flow bottleneck in an increasingly data-hungry world. Read more

Special Forces Demand Smaller, Lighter Electronics

by Ben Ames Military & Aerospace Electronics, February 2006 Commandos in the field, who scorn traditional military standards, are setting the bar high for night-vision devices, handheld radios, and batteries that must perform in far more demanding conditions than conventional military gear. Read more

Quality vs. Quantity in Engineering

by David Epstein Inside Higher Ed, 3 Mar 2006 Every spring, Jitendra Malik, chair of electrical engineering and computer science at the University of California at Berkeley, has a sitdown with students who have been accepted to the College of Engineering and are mulling over whether to attend. Malik has noticed a recent theme in the questions he gets from students, and especially from their parents. They want to know if they’re entering careers destined to be outsourced. Why might students admitted to one of the nation’s top engineering programs be worried about being getting a good job? And if students with enough ability to get into Berkeley engineering are afraid of enrolling, is the debate over increasing the number of engineering graduates nationwide missing the point? Read more

Metric State Space Reinforcement Learning for a Vision-Capable Mobile Robot

by Viktor Zhumatiy et al arXiv.org E-print Archive, 7 Mar 2006 We address the problem of autonomously learning controllers for vision-capable mobile robots. We extend McCallum's Nearest-Sequence Memory algorithm to allow for general metrics over state-action trajectories. We demonstrate the feasibility of our approach by successfully running our algorithm on a real mobile robot. The algorithm is novel and unique in that it (a) explores the environment and learns directly on a mobile robot without using a hand-made computer model as an intermediate step, (b) does not require manual discretization of the sensor input space, (c) works in piecewise continuous perceptual spaces, and (d) copes with partial observability. Together this allows learning from much less experience compared to previous methods. Read more

Wi-Fi Promises Internet Shake-Up

by Mark Ward BBC News, 8 March 2006 There is a good reason why the biggest wi-fi zones in the UK are in the City of London and Canary Wharf, with widespread wireless access being touted as the force behind the net's next wave of innovation. The first wave centred around the dotcom boom of the late 1990s when lucrative domains were snapped up, fledgling web businesses were established and everyone got dizzy on the potential of this new medium. Some of that potential is starting to be seen now in what is being called Web 2.0. Read more

Hybrids, We Never Knew Ya

by John Gartner Wired News, 7 Mar 2006 Marketers are jumping on the green-car movement and the gears are audibly grinding over what counts as a "hybrid vehicle." First applied to small sedans emphasizing fuel economy, the term is now blithely used to encompass a vast array of trucks, SUVs and luxury cars that in some cases offer only modest fuel savings over traditional vehicles, some critics charge. Read more

Optimization of Ionic Conductivity in Coped Ceria

by David A. Andersson et al. Proceedings of the National Academy of Sciences, 7 Mar 2006 Oxides with the cubic fluorite structure, e.g., ceria, are known to be good solid electrolytes when they are doped with cations of lower valence than the host cations. The high ionic conductivity of doped ceria makes it an attractive electrolyte for solid oxide fuel cells, whose prospects as an environmentally friendly power source are very promising. In these electrolytes, the current is carried by oxygen ions that are transported by oxygen vacancies, present to compensate for the lower charge of the dopant cations. Ionic conductivity in ceria is closely related to oxygen-vacancy formation and migration properties. A clear physical picture of the connection between the choice of a dopant and the improvement of ionic conductivity in ceria is still lacking. Here we present a quantum-mechanical first-principles study of the influence of different trivalent impurities on these properties. Our results reveal a remarkable correspondence between vacancy properties at the atomic level and the macroscopic ionic conductivity. The key parameters comprise migration barriers for bulk diffusion and vacancy-dopant interactions, represented by association (binding) energies of vacancy-dopant clusters. The interactions can be divided into repulsive elastic and attractive electronic parts. In the optimal electrolyte, these parts should balance. This finding offers a simple and clear way to narrow the search for superior dopants and combinations of dopants. The ideal dopant should have an effective atomic number between 61 (Pm) and 62 (Sm), and we elaborate that combinations of Nd/Sm and Pr/Gd show enhanced ionic conductivity, as compared with that for each element separately. Read more

Giant Electrocaloric Effect in Thin-Film PbZr0.95Ti0.05O3

by A. S. Mischenko et al. Science, 3 Mar 2006 An applied electric field can reversibly change the temperature of an electrocaloric material under adiabatic conditions, and the effect is strongest near phase transitions. We demonstrate a giant electrocaloric effect (0.48 kelvin per volt) in 350-nanometer PbZr_0.95Ti_0.05O₃ films near the ferroelectric Curie temperature of 222°C. A large electrocaloric effect may find application in electrical refrigeration. Read more

All-Optical Ultrafast Switching of Si Woodpile Photonic Band Gap Crystals

by Tijmen G. Euser et al. arXiv.org E-print Archive, 6 Mar 2006 We present ultrafast all-optical switching measurements of Si woodpile photonic band gap crystals at telecom frequencies. The crystals are homogeneously excited by a two-photon process. We probe the switching by measuring reflectivity over broad frequency ranges as a function of time. At short delay times, we observe that the photonic gap becomes narrower than in the unswitched case. After 1 ps, the complete gap has shifted to higher frequencies. This intricate behavior is the result of competing refractive index changes due to the electronic Kerr effect and to optically excited free carriers. The frequency shift of the band gap as a function of pump intensity agrees well with Fourier modal method calculations with no freely adjustable parameters. Read more

Multifunctional Chip to Meld Memory, Logic and Communications Functions

PhysOrg.com, 8 Mar 2006 The Department of Defense has awarded up to $5 million over five years for a multi-university research initiative to develop a chip that can independently process electronic, magnetic, and optical information and convert from any one type to any other type of information. Read more

Renault Concept Car Uses Novel Lighting Technology

optics.org News, 24 Feb 2006 Renault's new Altica concept car, described as a "sporty estate", features advanced LED-based front lighting. In what is described by Renault as a world first, the LED headlamps are covered with a "veil of light," which operates when the headlamps act as daytime running lights or sidelights. Read more

Demonstration of Quantum Telecloning of Optical Coherent States

by Satoshi Koike Physical Review Letters, 16 Feb 2006 A team of physicists in Japan and the UK has demonstrated "quantum telecloning" for the first time. Telecloning, which combines quantum cloning and teleportation into a single step, involves sending quantum information to more than one receiver. Read more

EAM-Based All-Optical Converter Runs at 40 Gbit/s

by Tami Freeman optics.org News, 2 Mar 2006 All-optical wavelength conversion -- the transfer of data streams from one wavelength carrier to another -- could play a central role in the management and routing of signals in next-generation optical networks. Importantly, say its advocates, it can help to decrease the number of optical-electrical-optical conversions. Read more

Hang on to the Bumps for a Smoother Flight

by Amarendra Swarup New Scientist, 4 Mar 2006 The performance-sapping turbulence of air passing over aircraft wings can be suppressed by carefully designed roughness in the surfaces. So says a team at KTH, the Royal Institute of Technology, Stockholm, Sweden, in defiance of the conventional wisdom that roughness inevitably promotes turbulence. The team's experiments could have far-reaching consequences for the aerospace industry, which spends vast amounts to reduce this costly effect. Read more

Hot Claims for Solar Power Future

New Scientist, 4 Mar 2006 Developed countries could be generating more electricity from sunlight than from nuclear power within the next 20 years. Writing in the latest issue of Nature Materials, Keith Barnham, a physicist and expert in solar cells at Imperial College London, claims that Germany is capable of increasing its solar-cell power output from less than a gigawatt at the moment to 12 gigawatts by 2012. Japan is planning to expand its output from 1.1 gigawatt in 2004 to 100 gigawatts by 2030. If the UK were similarly ambitious, it could replace its 12 gigawatts of nuclear power with solar power by 2023, the year by which all but one of its nuclear reactors could have closed. The US solar contribution meanwhile could expand well beyond 28 gigawatts by 2020, Barnham says.

Robotic 'Pack Mule' Displays Stunning Reflexes

by David Hambling NewScientist.com, 3 Mar 2006 A nimble, four-legged robot is so surefooted it can recover its balance even after being given a hefty kick. The machine, which moves like a cross between a goat and a pantomime horse, is being developed as a robotic pack mule for the US military. Read more

Aligned Carbon Nanotube-Polymer Hybrid Architectures for Diverse Flexible Electronic Applications

by Yung Joon Jung et al. Nano Letters, 1 Feb 2006 We present the fabrication and electrical characterization of a flexible hybrid composite structure using aligned multiwall carbon nanotube arrays in a poly(dimethylsiloxane) (PDMS) matrix. Using lithographically patterned nanotube arrays, one can make these structures at any length scale from submicrometer levels to bulk quantities. The PDMS matrix undergoes excellent conformal filling within the dense nanotube network, giving rise to extremely flexible conducting structures with unique electromechanical properties. We demonstrate its robustness against high stress conditions, under which the composite is found to retain its conducting nature. We also demonstrate that these structures can be utilized directly as flexible field-emission devices. Our devices show some of the best field-enhancement factors and turn-on electric fields reported so far. Read more

Long-Distance Lovers Can Still Drink Together

New Scientist, 8 Mar 2006 Could glowing, Wi-Fi wine glasses let people in long-distance relationships feel more in touch with their other half? Don't scoff: researchers in Boston at MIT's Media Lab -- that citadel of outside-the-box thinking -- believe so. When you and your partner both raise the high-tech glasses they will glow warmly, no matter how far apart you are. The idea is to give the feeling of a shared drinking experience. Read more

Watering Crops in the Wireless Age

New Scientist, 25 Feb 2006 A wireless sensor network to help farmers give their plants enough water -- but not too much -- will begin field trials next month. The network, being developed at info-tech firm National ICT Australia in Melbourne, consists of a few hundred wireless nodes distributed around a 10-hectare field of stone fruit in northern Victoria. Each node contains a computer chip and a Wi-Fi transmitter, linked with multiple sensors to measure soil moisture, leaf temperature and evaporation. The measurements are relayed to a central server, which adjusts the water supply to different areas via wirelessly controlled irrigation pumps. The team ultimately plans to create a system that can fine-tune irrigation to individual plants, and has already developed the necessary algorithms.

Nanomotor Rotates Microscale Objects

by Rienk Eelkema et al. Nature, 9 Mar 2006 Nanomachines of the future will require molecular-scale motors that can perform work and collectively induce controlled motion of much larger objects. We have designed a synthetic, light-driven molecular motor that is embedded in a liquid-crystal film and can rotate objects placed on the film that exceed the size of the motor molecule by a factor of 10,000. The changes in shape of the motor during the rotary steps cause a remarkable rotational reorganization of the liquid-crystal film and its surface relief, which ultimately causes the rotation of submillimetre-sized particles on the film. Read more

Initiation of Shape-Memory Effect by Inductive Heating of Magnetic Nanoparticles in Thermoplastic Polymers

by R. Mohr et al. Proceedings of the National Academy of Sciences, 7 Mar 2006 Researchers at the Institute of Polymer Research in Germany and DKI German Institute for Polymers have incorporated magnetic nanoparticles in thermoplastic polymers to create shape-memory materials. Applying a magnetic field to a temporarily deformed piece of the material causes it to change back to its original shape, a phenomenon that could be exploited in medical applications. Read more

Self-Assembled Nanofold Network Formation on Layered Crystal Surfaces during Metal Intercalation

by E. Spiecker et al. Physical Review Letters, 27 Feb 2006 Researchers at Lawrence Berkeley National Laboratory, US, and the Christian Albrechts University of Kiel, Germany, have solved the mystery of how nanostructured networks form when transition metal dichalcogenide crystals are bombarded with metal atoms. It turns out that the structures self-assemble when the top layer of the crystal deforms to relieve compressive stress. Read more

Improved Fidelity of Triggered Entangled Photons from Single Quantum Dots

by Robert J Young et al. New Journal of Physics, 23 Feb 2006 Scientists in the UK have been able to generate pairs of entangled photons from a nanoscale crystal of semiconductor known as a "quantum dot" far more efficiently than was possible before. The breakthrough was made by Andrew Shields at Toshiba and colleagues at the University of Cambridge, who produced entangled photons with an efficiency of 70% -- compared to a previous best figure of 49%. The improved performance approaches that required for useful applications, which means that devices emitting entangled light could one day be as common as lasers and light-emitting diodes. Read more

Carbon Fiber Cars Could Put US on Highway to Efficiency

DOE/Oak Ridge National Laboratory Public Release, 6 Mar 2006 Highways of tomorrow might be filled with lighter, cleaner and more fuel-efficient automobiles made in part from recycled plastics, lignin from wood pulp and cellulose. Read more

Enhancement of the Critical Current Density of YBa2Cu3Ox Superconductors under Hydrostatic Pressure

by T. Tomita & J. S. Schilling Physical Review Letters, 22 Feb 2006 Nobody completely understands superconductors. So fathom how James S. Schilling led a team that makes the phenomenon work better. Read more

Exceptional H2 Saturation Uptake in Microporous Metal-Organic Frameworks

by Antek G. Wong-Foy, Adam J. Matzger, & Omar M. Yaghi Journal of the American Chemical Society, 1 Mar 2006 (online) Chemists at UCLA and the University of Michigan report an advance toward the goal of cars that run on hydrogen rather than gasoline. While the U.S. Department of Energy estimates that practical hydrogen fuel will require concentrations of at least 6.5 percent, the chemists have achieved concentrations of 7.5 percent -- nearly three times as much as has been reported previously -- but at a very low temperature. Read more

Intel Tips New, Revamped Microarchitecture

by Mark LaPedus EE Times, 7 Mar 2006 Hoping to regain lost momentum in the microprocessor market, Intel Corp. moved to renew its x86-based chip line by disclosing details of its new and long-awaited microarchitecture technology. Read more

On Non-Coherent MIMO Channels in the Wideband Regime

by Siddharth Ray, Muriel Medard, & Lizhong Zheng arXiv.org E-pring Archive, 3 Mar 2006 We consider a multiple-input, multiple-output wideband Rayleigh block fading channel where the channel state is unknown to both the transmitter and the receiver and there is only an average power constraint on the input. We compute the capacity and analyze its dependence on coherence length, number of antennas and receive signal-to-noise ratio per degree of freedom. We establish conditions on the coherence length and number of antennas for the non-coherent channel to have a "near coherent" performance in the wideband regime. We also propose a signaling scheme that is near-capacity achieving in this regime. Read more