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April 26, 2006, 6:59 PM CT

Water and Nanoelectronics Will Mix to Create Ultra-Dense Memory Storage Devices

Water and Nanoelectronics Will Mix to Create Ultra-Dense Memory Storage Devices
Excessive moisture can typically wreak havoc on electronic devices, but now researchers have demonstrated that a little water can help create ultra-dense storage systems for computers and electronics.

A team of experimentalists and theorists at the University of Pennsylvania, Drexel University and Harvard University has proposed a new and surprisingly effective means of stabilizing and controlling ferroelectricity in nanostructures: terminating their surfaces with fragments of water. Ferroelectrics are technologically important "smart" materials for many applications because they have local dipoles, which can switch up and down to encode and store information. The team's work is reported in the recent issue of Nano Letters.

"It is astonishing to see that a single wire of even a few atoms across can act as a stable and switchable dipole memory element," Jonathan Spanier, assistant professor of materials science and engineering at Drexel, said.

Spanier and his colleagues successfully demonstrated the benefits of using water to stabilize memory bits in segments of oxide nanowires that are only about 3 billionths of a meter wide.

"We have been interested in how water sticks to oxides," Alexie Kolpak, Penn graduate student in theoretical physical chemistry, said. "We are particularly excited that water is the key ingredient in making these wires 'remember' their state".........

Posted by: John      Permalink         Source


April 25, 2006, 8:11 PM CT

Nanedi Valles Valley System On Mars

Nanedi Valles Valley System On Mars

These images, taken by the High Resolution Stereo Camera (HRSC) on board ESA's Mars Express spacecraft, show the Nanedi Valles valley system, a steep-sided feature that may have been formed in part by free-flowing water.

The HRSC obtained these images on 3 October 2004 during orbit 905 at a ground resolution of approximately 18 metres per pixel. The images have been rotated 90 degrees clockwise, so that north is to the right.

They show the region of Nanedi Valles, a roughly 800-kilometre valley extending southwest-northeast and lying at approximately 6.0 degree North and 312 degree East in the region of Xanthe Terra, southwest of Chryse Planitia.

In the colour image, Nanedi Valles ranges from approximately 0.8- to 5.0-kilometre wide and extends to a maximum of about 500 metres below the surrounding plains. This valley is relatively flat-floored and steep-sloped, and exhibits meanders and a merging of two branches in the north.

The origin of these striking features remains heavily debated.

Some scientists point to sapping (erosion caused by ground-water outflow), while others suggest that flow of liquid beneath an ice cover or collapse of the surface in association with liquid flow is responsible for the valley's formation.

While the debate continues, it seems likely that some sort of continuous flow rather than a single flooding event created these features.........

Posted by: Edwin      Permalink         Source


April 25, 2006, 8:06 PM CT

Prototype For Revolutionary One-metre Wide Vehicle

Prototype For Revolutionary One-metre Wide Vehicle
The prototype of a revolutionary new type of vehicle only one metre wide specially designed for cities has been developed by a team of European scientists. The vehicle combines the safety of a micro-car and the manoeuvrability of a motorbike, while being more fuel-efficient and less polluting than other vehicles.

The CLEVER (Compact Low Emission Vehicle for Urban Transport) vehicle is a £1.5 million collaborative project which has involved nine European partners from industry and research, including the University of Bath.

The three-year international project has produced a tilting three-wheeled vehicle that is fully enclosed and has seats for the driver and a passenger. Its strengthened frame protects the driver in a crash and the vehicle has a top speed of approximately 60 mph (about 100 kph) and an acceleration of 0-40 mph (60 kph) in seven seconds.

At just over three feet (1 metre) wide, it is 20 inches (0.5 metres) narrower than a micro-car, and three feet narrower than a medium sized conventional car. This reduced width means more efficient parking bays, and the possibility of narrower lanes for such vehicles.

The vehicle is different from prior attempts to create a small urban vehicle in that it is fully enclosed in a metal framework, is stylishly designed and is much safer. Its roof is as high as conventional cars, and it carries one passenger, who sits behind the driver.........

Posted by: John      Permalink         Source


April 25, 2006, 7:27 PM CT

Black Holes Are "Green"

Black Holes Are
Black holes are the most fuel efficient engines in the Universe, as per a new study using NASA's Chandra X-ray Observatory. By making the first direct estimate of how efficient or "green" black holes are, this work gives insight into how black holes generate energy and affect their environment.

The new Chandra finding shows that most of the energy released by matter falling toward a supermassive black hole is in the form of high-energy jets traveling at near the speed of light away from the black hole. This is an important step in understanding how such jets can be launched from magnetized disks of gas near the event horizon of a black hole.

"Just as with cars, it's critical to know the fuel efficiency of black holes," said lead author Steve Allen of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University, and the Stanford Linear Accelerator Center. "Without this information, we cannot figure out what is going on under the hood, so to speak, or what the engine can do".

Allen and his team used Chandra to study nine supermassive black holes at the centers of elliptical galaxies. These black holes are relatively old and generate much less radiation than quasars, rapidly growing supermassive black holes seen in the early Universe. The surprise came when the Chandra results showed that these "quiet" black holes are all producing much more energy in jets of high-energy particles than in visible light or X-rays. These jets create huge bubbles, or cavities, in the hot gas in the galaxies.........

Posted by: Edwin      Permalink         Source


April 24, 2006, 7:32 PM CT

Brown Dwarfs Weighed Directly for First Time

Brown Dwarfs Weighed Directly for First Time
Astronomers have made the first direct mass measurements of brown dwarfs by following a pair of the "failed" stars in their cosmic dance around one another. The breakthrough could allow other suspected brown dwarfs to be positively identified.

Brown dwarfs are intermediate objects - too large to be planets, yet too small to be stars. They are sometimes defined as having between 13 and 75 times the mass of Jupiter.........

Posted by: Edwin      Permalink         Source


April 24, 2006, 7:20 PM CT

Harvesting Daylight And Saving Energy

Harvesting Daylight And Saving Energy
Scientists at Rensselaer Polytechnic Institute's Lighting Research Center (LRC) have developed a simple, cost-effective, energy-saving device designed to harvest daylight automatically. The DaySwitch was designed as an alternative to traditional dimming ballast systems that adjust light levels by reducing the lamp current.

"The DaySwitch is designed to build end-use efficiency by reducing light energy usage in commercial buildings and maintaining occupant satisfaction," said Peter Morante, director of energy programs at the LRC. "It is estimated that the DaySwitch will be able to reduce lighting energy consumption by 30 percent in buildings with significant daylight contribution through windows or skylights, allowing for a payback period of approximately three years".

Typical dimming systems have several drawbacks, including high initial cost and difficult photosensor programming and installation. As a result, dimming systems have not permeated the market, according to Morante.

The DaySwitch development team, led by Morante and Richard Pysar, an electronic design engineer at the LRC, created a low-cost prototype to control individual light fixtures, unlike traditional systems where one sensor controls numerous lamps. Individual control provides flexibility for on/off control and simple installation.........

Posted by: John      Permalink         Source


April 24, 2006, 6:50 PM CT

Nanotechnology May Find Disease Before It Starts

Nanotechnology May Find Disease Before It Starts
Nanotechnology may one day help physicians detect the very earliest stages of serious diseases like cancer, a new study suggests.

It would do so by improving the quality of images produced by one of the most common diagnostic tools used in doctors' offices - the ultrasound machine.

In laboratory experiments on mice, scientists found that nano-sized particles injected into the animals improved the resulting images. This study is one of the first reports showing that ultrasound can detect these tiny particles when they are inside the body, said Thomas Rosol, a study co-author and dean of the college of veterinary medicine at Ohio State University.

"Given their tiny size, nobody thought it would be possible for ultrasound to detect nanoparticles," he said.

It turns out that not only can ultrasound waves sense nanoparticles, but the particles can brighten the resulting image. One day, those bright spots may indicate that a few cells in the area may be on the verge of mutating and growing out of control.

"The long-term goal is to use this technology to improve our ability to identify very early cancers and other diseases," said Jun Liu, a study co-author and an assistant professor of biomedical engineering at Ohio State University. "We ultimately want to identify disease at its cellular level, at its very earliest stage".........

Posted by: John      Permalink         Source


April 24, 2006, 6:47 AM CT

Next Generation Fuel Cells

Next Generation Fuel Cells
The pressure to develop cleaner, more efficient single sources of heat and electrical energy is the driving force behind the development of solid oxide fuel cells (SOFCs) at NRC and elsewhere. However, if SOFCs are to become commercially viable, production costs must be lower and the reliability, as well as durability of these systems needs improvement.

NRC Institute for Chemical Process and Environmental Technology (NRC-ICPET) researchers, Drs. Pamela Whitfield, Gisele Amow and Isobel Davidson, teamed up with Dr. Stephen Skinner (Department of Materials, Imperial College, U.K.) to collaborate on a project that tackled these challenges.

The research was funded by the NRC-British Council Joint S&T Fund and involved comparing methods to synthesize novel cathode materials using a conventional Pechini process and a non-conventional production method - microwave-assisted synthesis. The novel cathode materials produced by both methods were then evaluated for their potential use in intermediate temperature SOFCs.

The two teams worked together on developing new cathode compositions in a family of oxides known to be hyperstoichiometric in oxygen. In this class of materials the ionic transport of oxygen is augmented by interstitial oxide ions within the structure's crystal lattice. Led by Dr. Skinner, the British team provided expertise on measuring oxide ion mobility using a technique of isotopic exchange and secondary ion mass spectroscopy. The research led to new cathode compositions with greater ionic conductivity, thereby decreasing the amount of energy necessary for oxygen ion mobility and enabling the fuel cell to operate at lower temperatures. Lower operating temperatures can increase the durability of SOFCs and makes smaller-scale applications, such as portable power units, more feasible.........

Posted by: John      Permalink         Source


April 22, 2006, 6:26 PM CT

The Giant Magellan Telescope Group Grows

The Giant Magellan Telescope Group Grows
The Giant Magellan Telescope (GMT), the first extremely large new-generation telescope to begin production, has gained a new partner-the Australian National University (ANU) http://www.anu.edu.au/. The announcement made today comes from the Giant Magellan Telescope consortium. Other consortium members include the Carnegie Observatories, Harvard University, Smithsonian Astrophysical Observatory, University of Arizona, University of Michigan, Massachusetts Institute of Technology, University of Texas at Austin, and Texas A&M University.

"The addition of the Australian National University to the GMT consortium is the most recent indication of the momentum that the project is generating," commented Wendy Freedman, chair of the GMT board and the Crawford H. Greenewalt director of the Carnegie Observatories. "We couldn't be more pleased with ANU's participation. We all share a common goal of probing the most important questions in astronomy facing us over the next generation-the mysteries of dark energy, dark matter, and black holes; the birth of stars and planetary systems in our Milky Way; the genesis of galaxies; and much more".

"The GMT represents a new epoch for astronomy," stated Richard Meserve, president of the Carnegie Institution. "Now, with a group of nine, the consortium is well on its way to accomplishing its goals," he added.........

Posted by: Edwin      Permalink         Source


April 22, 2006, 6:01 PM CT

Magnetic Nanotechnology Cancer And Computing

Magnetic Nanotechnology  Cancer And Computing
Detecting cancer and reinventing computing are two challenges that seemingly have little, if anything, to do with each other. That is, unless you are a nanotechnologist like Shan Wang, an associate professor of materials science and engineering and of electrical engineering at Stanford. To him, the problems are two sides of the same coin, or more aptly, opposite poles of the same magnet.

"We have known for a long time that magnetism is a fundamental property of all materials and it has found wide applications in electronics and biology, like hard disk drives and magnetic resonance imaging, but there is also great potential to now apply magnetism at the nanoscale," Wang said in an interview in his office at the Geballe Laboratory for Advanced Materials.

There Wang is tuning the characteristics of tiny magnets-on the scale of a billionth of a meter-to help address both cancer and computing. One part of his research group is developing an ultrasensitive detector of DNA and proteins, including proteins associated with cancer. With some of his students, Wang also is making key advances in "spintronics," a new computing technology that could augment or replace silicon microelectronics when progress there is no longer possible because of physical limitations.

Wang's expertise and promising results have made him an important member of two research centers announced this year. On Feb. 27, the National Cancer Institute awarded Stanford $20 million over five years to establish a Center of Cancer Nanotechnology Excellence Wang co-directs with radiology Professor Sanjiv Gambhir. Then on March 9, the university joined with three University of California campuses to announce the Western Institute of Nanoelectronics, a center headquartered at UCLA and dedicated to spintronics research.........

Posted by: John      Permalink         Source


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