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What is graphene? Here’s what you need to know about a material that could be the next silicon

What is graphene? Here’s what you need to know about a material that could be the next silicon
Graphene, an emerging material that could change the way electronic components are made and help computing performance continue to grow, is everywhere in the research world these days. This month alone, advancements suggested it could boost internet speeds, serve as a touch sensitive coating and extend the lives of computers. It is stronger than diamond and conducts electricity and heat better than any material ever discovered, and it will likely play an important role in many products and processes in the future. What is graphene? Graphene is made of a single layer of carbon atoms that are bonded together in a repeating pattern of hexagons. Carbon is an incredibly versatile element. These single layers of carbon atoms provide the foundation for other important materials. How was it discovered? Chances are good that you have made graphene many times in your life. Graphene was first studied theoretically in the 1940s. Why is it unusual? What can it be used for? What are the critiques? Related:  EnergyTechnology and Web

Nuclear Fusion Reactions See Net Gain in Energy Using controlled nuclear fusion for a source of virtually unlimited power that is pollution-free has been a dream of physicists since Einstein’s day - but many had written the process off as science fiction. Though it is still a long way off, a new breakthrough has occurred where researchers actually saw a net gain in energy following a fusion reaction. The announcement comes from lead author Omar Hurricane from the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory and was published in Nature. Nuclear fusion happens naturally in the cores of stars. As atoms from lighter elements smash into one another, the nuclei fuse to create a heavier element and energy is released. If this happens in large enough of quantities it starts a process called ‘ignition’ which is a chain reaction of more atoms fusing and releasing more energy until there is a self-sustaining energy source.

Researchers make magnetic graphene -- ScienceDaily Graphene, a one-atom thick sheet of carbon atoms arranged in a hexagonal lattice, has many desirable properties. Magnetism alas is not one of them. Magnetism can be induced in graphene by doping it with magnetic impurities, but this doping tends to disrupt graphene's electronic properties. Now a team of physicists at the University of California, Riverside has found an ingenious way to induce magnetism in graphene while also preserving graphene's electronic properties. "This is the first time that graphene has been made magnetic this way," said Jing Shi, a professor of physics and astronomy, whose lab led the research. The finding has the potential to increase graphene's use in computers, as in computer chips that use electronic spin to store data. Study results appeared online earlier this month in Physical Review Letters. The magnetic insulator Shi and his team used was yttrium iron garnet grown by laser molecular beam epitaxy in his lab.

Technology and Education La pile du futur est née, ultra-puissante et biodégradable Charger un téléphone en 30 secondes, une voiture électrique en l’espace de quelques minutes, c’est pour bientôt ! Deux scientifiques de l’université de Californie à Los Angeles ont créé par hasard une pile super-puissante et biodégradable lors de leurs travaux sur le graphène, rapporte le site Co.Design. Les résultats de leur recherche ont été publiés dans la revue Nature. Le graphène est un matériau révolutionnaire découvert en 2004 qui a permis à ses inventeurs de remporter le Nobel de physique en 2010. C’est en cherchant une manière plus pratique de fabriquer du graphène que Richard Kaner et Maher El-Kady ont mis au point le «super-condensateur»: une nouvelle pile flexible, superpuissante et biodégradable qui pourrait bien être la potentielle alimentation des gadgets ou systèmes électroniques de nouvelle génération. Les scientifiques expliquent leur découverte dans la vidéo ci-dessus de présentation. Ce super-condensateur combine les avantages de la pile classique et du condensateur.

Graphene's love affair with water: Water filters allow precise and fast sieving of salts and organic molecules -- ScienceDaily Graphene has proven itself as a wonder material with a vast range of unique properties. Among the least-known marvels of graphene is its strange love affair with water. Graphene is hydrophobic -- it repels water -- but narrow capillaries made from graphene vigorously suck in water allowing its rapid permeation, if the water layer is only one atom thick -- that is, as thin as graphene itself. This bizarre property has attracted intense academic and industrial interest with intent to develop new water filtration and desalination technologies. One-atom-wide graphene capillaries can now be made easily and cheaply by piling layers of graphene oxide -- a derivative of graphene -- on top of each other. Two years ago, University of Manchester researchers discovered that thin membranes made from such laminates were impermeable to all gases and vapours, except for water. Small salts with a size of less than nine Angstroms can flow along but larger ions or molecules are blocked.

FDA approves a life-like prosthetic arm from the man who invented the Segway After years of testing, the FDA today approved a new type of prosthetic arm that its makers claim will bring a whole new level of control to amputees. Known as the "Luke" arm or DEKA Arm System, Segway inventor Dean Kamen has been involved in its development and unlike existing prosthetics, it can understand multiple commands at once, giving its wearers "near-natural" control of the limb. As demonstrated in the videos embedded after the break, tests show wearers can get back to easily performing tasks like using keys and locks, brushing their hair, removing papers from an envelope, or picking up an egg without breaking it. While we've seen demos using other mind control techniques, the one approved for sale does its magic with electromyogram (EMG) sensors activated by the wearer contracting muscles close to where the prosthesis is attached or on their feet, which an embedded computer translates into movement. Another triumph here is the (relative) speed of its approval. Comments

New Battery Biodegrades Inside The Human Body When medical devices are implanted, there is often an issue with providing the device with power. There are wireless power sources available, but they are relatively bulky and are often too large for devices that are deep in the body and obstructed by muscle and bone. Putting a battery in with the implanted device is ideal, but there are some safety considerations involved. However, a new battery developed by John Rogers of the University of Illinois at Urbana-Champaign is biodegradable and dissolves completely . The anodes of the battery are made out of magnesium foil, while the cathode can either be iron, tungsten, or molybdenum. There are other batteries in development seeking to achieve biocompatibility, including one by Christopher Bettinger from Carnegie Mellon which is a sodium-ion battery with electrodes generated from cuttlefish ink. Aside from biological implants, these batteries could be used for environmental purposes, like after oil spills.

'Soft' approach leads to revolutionary energy storage: Graphene-based supercapacitors Monash University researchers have brought next generation energy storage closer with an engineering first -- a graphene-based device that is compact, yet lasts as long as a conventional battery. Published today in Science, a research team led by Professor Dan Li of the Department of Materials Engineering has developed a completely new strategy to engineer graphene-based supercapacitors (SC), making them viable for widespread use in renewable energy storage, portable electronics and electric vehicles. SCs are generally made of highly porous carbon impregnated with a liquid electrolyte to transport the electrical charge. Known for their almost indefinite lifespan and the ability to re-charge in seconds, the drawback of existing SCs is their low energy-storage-to-volume ratio -- known as energy density. Low energy density of five to eight Watt-hours per litre, means SCs are unfeasibly large or must be re-charged frequently.

Why Apple vs. Google Is the Most Important Battle in Tech In the 1990s, Microsoft Internet Explorer battled Netscape Navigator in the great Web-browser wars. In the 2000s, Google and Yahoo locked horns over Internet search — and we know how that turned out. Today, the latest high-stakes tech conflict is between Apple’s iPhone and Google’s Android mobile operating system for supremacy in the smart-phone market. Each of these clashes defined an era of Internet history. Apple and Google realize how huge the stakes are in this fight. (MORE: Google Chairman Eric Schmidt Raps Apple on iPhone Maps, Floats Yahoo! This smart-phone showdown is important because Apple and Google are advancing radically different business models to the fight. Each company has been successful with its respective strategy: Apple makes $1 billion per month on iPhone sales, and the device is considered the gold standard for smart-phone design. (MORE: Patent Peace: Apple’s Tim Cook, Google’s Larry Page in CEO Talks)

How A Drop of Seawater on Graphene Generates Electricity Ever since the early 19th century, scientists have known that an electric potential can be generated by simply driving an ionic liquid -- fluids with charged ions in it, like water or sodium chloride solution -- through channels or holes under a pressure gradient. The latest in hydroelectric power involves generating voltage by immersing carbon nanotubes in flowing liquids. But scientists have never quite figured out exactly how this happens -- and generating electricity without a pressure gradient remains a challenge. They experimented with a wide range of various parameters, and they found that the resulting electric potential is proportional to the velocity (of the dragged droplet) and the number of droplets. Other factors they took into account: concentration and ionic species of the drop, as well as the number of graphene layers. To demonstrate the potential of this electrokinetic phenomenon, they scaled it up and created an energy-harvesting device.

Graphene supercapacitor breaks storage record Researchers in the US have made a graphene-based supercapacitor that can store as much energy per unit mass as nickel metal hydride batteries – but unlike batteries, it can be charged or discharged in just minutes or even seconds. The new device has a specific energy density of 85.6 Wh/kg at room temperature and 136 Wh/kg at 80 °C. These are the highest ever values for "electric double layer" supercapacitors based on carbon nanomaterials. Supercapacitors, more accurately known as electric double-layer capacitors or electrochemical capacitors, can store much more charge than conventional capacitors. The new device was made by Bor Jang of US-based Nanotek Instruments and colleagues. The researchers coat the resulting slurry onto the surface of a current collector and assemble coin-sized capacitors in a glove box. Fast charging We believe that this is truly a breakthrough in energy technology Bor Jang, Nanotek Instruments The work was reported in Nano Letters.

Education Week's Digital Directions: 'Second Life' Struggles to Catch On With Educators Published Online: June 15, 2011 Published in Print: June 15, 2011, as Avatars Wanted Features During an informal “campfire chat” on the ISTE Second Life Island, participants discuss the themes from a series of virtual speaker presentations. —Courtesy of ISTE Teachers from around the country are gathering together to visit the Alamo in San Antonio, the Holocaust Memorial Museum in Washington, and the Louvre in France in the span of a few hours without shelling out a dime. Those are the kinds of virtual experiences, made possible by a computer and a high-speed Internet connection, that first attracted educators to Second Life, technology experts say. Initially, there was a lot of excitement about the possibilities of using Second Life as a professional-development tool for educators. But, for a number of reasons, those expectations have largely fallen short, offering cautionary lessons about using technology for professional development. Hosting Virtual Events ‘Friends in Real Life’ 1. 2. 3. 4.

New Dual Carbon Battery Charges 20x Faster Than Lithium Ion Power Japan Plus has announced an innovative new battery that charges up to twenty times faster and lasts longer than high-end lithium ion batteries. The company boasts that electric vehicles with the ability to drive 300 miles (480 km) on a single charge may soon be a reality. The Ryden dual carbon new battery is cheaper, safer, and 100% recyclable, making it an attractive option that could bring high-performance electric cars to market more quickly. “Power Japan Plus is a materials engineer for a new class of carbon material that balances economics, performance and sustainability in a world of constrained resources,” said Dou Kani, CEO of Power Japan Plus in a press release. “The Ryden dual carbon battery is the energy storage breakthrough needed to bring green technology like electric vehicles to mass market.” The battery was developed in partnership with Kyushu University in Japan.

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