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with Tegra 2 introduce the world’s fastest dual-core smartphone with amazing video features and multitasking capabilities. It contains dual-core Tegra2  1GHz processor,it is fully capable of recording videos in crisp 1080p with its 8-megapixel rear camera unit. There’s also a front-facing one at 1.3 megapixels for the video-calling.

Dual-core technology is the next leap forward in mobile technology so this is no small achievement to be the first to offer a smartphone utilizing this technology,” said Dr. Jong-seok Park, CEO and President of LG Electronics Mobile Communications Company. “With unique features such as HDMI (High Definition Multimedia Interface) mirroring and exceptional graphics performance, the LG Optimus 2X is proof of LG’s commitment to high-end smartphones in 2011.”

Developed by graphics processor powerhouse NVIDIA?, the dual-core Tegra 2 system-on-a-chip found in the LG Optimus 2X runs at a clock speed of 1GHz and boasts low power consumption and high performance for playing video and audio. Users will experience faster web browsing and smoother gameplay compared with single-core processors running at the same speed as well as instantaneous touch response and seamless multitasking between applications.

The LG Optimus 2X offers 1080p HD video playback and recording with HDMI mirroring that expands content on external displays to full HD quality. The LG Optimus 2X can connect wirelessly to any DLNA (Digital Living Network Alliance) compatible digital device such as HD TVs for a console-like gaming experience taking full advantage of the phone’s HDMI mirroring, accelerometer and gyro sensor. The smartphone also includes both rear- and front-facing cameras, microSD memory expandability, Micro-USB port and a hefty 1500mAh battery.

The LG Optimus 2X will be available in Korea next month with countries in Europe and Asia to follow. The phone will initially be released with Android 2.2 (Froyo) and will be upgradeable to Android 2.3 (Gingerbread). The upgrade schedule will be announced in local markets in due course.

Key specifications:

– 1Ghz Dual-core Processor (NVIDIA Tegra 2)
– 4-inch WVGA screen
– 8GB memory (up to 32GB via microSD)
– 1,500 mAh battery
– 8 megapixel rear camera and 1.3 megapixel front camera
– HDMI mirroring
– 1080p MPEG-4/H.264 playback and recording

Research by TU Delft shows that Dutch power stations are able to cope at any time in the future with variations in demand for electricity and supply of wind power, as long as use is made of up-to-date wind forecasts. PhD candidate Bart Ummels also demonstrates that there is no need for energy storage facilities. Ummels will receive his PhD on this topic on Thursday 26 February.

Wind is variable and can only partially be predicted. The large-scale use of wind power in the electricity system is therefore tricky. PhD candidate Bart Ummels MSc. investigated the consequences of using a substantial amount of wind power within the Dutch electricity system. He used simulation models, such as those developed by transmission system operator TenneT, to pinpoint potential problems (and solutions).

His results indicate that wind power requires greater flexibility from existing power stations. Sometimes larger reserves are needed, but more frequently power stations will have to decrease production in order to make room for wind-generated power. It is therefore essential to continually recalculate the commitment of power stations using the latest wind forecasts. This reduces potential forecast errors and enables wind power to be integrated more efficiently.

Ummels looked at wind power up to 12 GW, 8 GW of which at sea, which is enough to meet about one third of the Netherlands’ demand for electricity. Dutch power stations are able to cope at any time in the future with variations in demand for electricity and supply of wind power, as long as use is made of up-to-date, improved wind forecasts. It is TenneT’s task to integrate large-scale wind power into the electricity grid. Lex Hartman, TenneT’s Director of Corporate Development:  “in a joint effort, TU Delft and TenneT further developed the simulation model that can be used to study the integration of large-scale wind power. The results show that in the Netherlands we can integrate between 4 GW and 10 GW into the grid without needing any additional measures.

Surpluses

Ummels: ‘Instead of the common question ‘What do we do when the wind isn’t blowing?’, the more relevant question is ‘Where do we put all the electricity if it is very windy at night?’. This is because, for instance, a coal-fired power station cannot simply be turned off. One solution is provided by the international trade in electricity, because other countries often can use the surplus. Moreover, a broadening of the ‘opening hours’ of the international electricity market benefits wind power. At the moment, utilities determine one day ahead how much electricity they intend to purchase or sell abroad. Wind power can be better used if the time difference between the trade and the wind forecast is smaller.’

No energy storage

Ummels’ research also demonstrates that energy storage is not required. The results indicate that the international electricity market is a promising and cheaper solution for the use of wind power.

Making power stations more flexible is also better than storage. The use of heating boilers, for instance, means that combined heat and power plants operate more flexibly, which can consequently free up capacity for wind power at night.

The use of wind power in the Dutch electricity system could lead to a reduction in production costs of EUR1.5 billion annually and a reduction in CO₂ emissions of 19 million tons a year.

Story Source:

The above story is reprinted from materials provided by Delft University of Technology.

Researchers have developed a new technique for powering nanometer-scale devices without the need for bulky energy sources such as batteries.
By converting mechanical energy from body movement, muscle stretching or water flow into electricity, these “nanogenerators” could make possible a new class of self-powered implantable medical devices, sensors and portable electronics.
Described in the April 14th issue of the journal Science, the nanogenerators produce current by bending and then releasing zinc oxide nanowires — which are both piezoelectric and semiconducting. The research was sponsored by the National Science Foundation (NSF), the NASA Vehicle Systems Program and the Defense Advanced Research Projects Agency (DARPA).
“There is a lot of mechanical energy available in our environment,” said Zhong Lin Wang, a Regents Professor in the School of Materials Science and Engineering at the Georgia Institute of Technology. “Our nanogenerators can convert this mechanical energy to electrical energy. This could potentially open up a lot of possibilities for the future of nanotechnology.”
Nanotechnology researchers have proposed and developed a broad range of nanoscale devices, but their use has been limited by the sources of energy available to power them. Conventional batteries make the nanoscale systems too large, and the toxic contents of batteries limit their use in the body. Other potential power sources also suffer from significant drawbacks.
“We can build nanodevices that are very small, but if the complete integrated system must include a large power source, that defeats the purpose,” added Wang, who also holds affiliated faculty positions at Peking University and the National Center for Nanoscience and Technology of China.
The nanogenerators developed by Wang and graduate student Jinhui Song use the very small piezoelectric discharges created when zinc oxide nanowires are bent and then released. By building interconnected arrays containing millions of such wires, Wang believes he can produce enough current to power nanoscale devices.
To study the effect, the researchers grew arrays of zinc oxide nanowires, then used an atomic-force microscope tip to deflect individual wires. As a wire was contacted and deflected by the tip, stretching on one side of the structure and compression on the other side created a charge separation — positive on the stretched side and negative on the compressed side — due to the piezoelectric effect.
The charges were preserved in the nanowire because a Schottky barrier was formed between the AFM tip and the nanowire. The coupling between semiconducting and piezoelectric properties resulted in the charging and discharging process when the tip scanned across the nanowire, Wang explained.
When the tip lost contact with the wire, the strain was released — and the researchers measured an electrical current. After the strain release, the nanowire vibrated through many cycles, but the electrical discharge was measured only at the instant when the strain was released.
To rule out other potential sources of the current, the researchers conducted similar tests using structures that were not piezoelectric or semiconducting. “After a variety of tests, we are confident that what we are seeing is a piezoelectric-induced discharge process,” Wang said.
The researchers grew the nanowire arrays using a standard vapor-liquid-solid process in a small tube furnace. First, gold nanoparticles were deposited onto a sapphire substrate placed in one end of the furnace. An argon carrier gas was then flowed into the furnace as zinc oxide powder was heated. The nanowires grew beneath the gold nanoparticles, which serve as catalysts.
The resulting arrays contained vertically-aligned nanowires that ranged from 200 to 500 nanometers in length and 20 to 40 nanometers in diameter. The wires grew approximately 100 nanometers apart, as determined by the placement of the gold nanoparticles.
A film of zinc oxide also grew between the wires on the substrate surface, creating an electrical connection between the wires. To that conductive substrate, the researchers attached an electrode for measuring current flow.
Though attractive for use inside the body because zinc oxide is non-toxic, the nanogenerators could also be used wherever mechanical energy — hydraulic motion of seawater, wind or the motion of a foot inside a shoe — is available. The nanowires can be grown not only on crystal substrates, but also on polymer-based films. Use of flexible polymer substrates could one day allow portable devices to be powered by the movement of their users.
“You could envision having these nanogenerators in your shoes to produce electricity as you walk,” Wang said. “This could be beneficial to soldiers in the field, who now depend on batteries to power their electrical equipment. As long as the soldiers were moving, they could generate electricity.”
Current could also be produced by placing the nanowire arrays into fields of acoustic or ultrasonic energy. Though they are ceramic materials, the nanowires can bend as much as 50 degrees without breaking.
The next step in the research will be to maximize the power produced by an array of the new nanogenerators. Wang estimates that they can convert as much as 30 percent of the input mechanical energy into electrical energy for a single cycle of vibration. That could allow a nanowire array just 10 microns square to power a single nanoscale device — if all the power generated by the nanowire array can be successfully collected.
“Our bodies are good at converting chemical energy from glucose into the mechanical energy of our muscles,” Wang noted. “These nanogenerators can take that mechanical energy and convert it to electrical energy for powering devices inside the body. This could open up tremendous possibilities for self-powered implantable medical devices.”

Story Source:
The above story is reprinted from materials provided by Georgia Institute of Technology.

Blinking numbers on a liquid-crystal display (LCD) often indicate that a device’s clock needs resetting. But in the laboratory of Zhong Lin Wang at Georgia Tech, the blinking number on a small LCD signals the success of a five-year effort to power conventional electronic devices with nanoscale generators that harvest mechanical energy from the environment using an array of tiny nanowires.

In this case, the mechanical energy comes from compressing a nanogenerator between two fingers, but it could also come from a heartbeat, the pounding of a hiker’s shoe on a trail, the rustling of a shirt, or the vibration of a heavy machine. While these nanogenerators will never produce large amounts of electricity for conventional purposes, they could be used to power nanoscale and microscale devices — and even to recharge pacemakers or iPods.

Wang’s nanogenerators rely on the piezoelectric effect seen in crystalline materials such as zinc oxide, in which an electric charge potential is created when structures made from the material are flexed or compressed. By capturing and combining the charges from millions of these nanoscale zinc oxide wires, Wang and his research team can produce as much as three volts — and up to 300 nanoamps.

“By simplifying our design, making it more robust and integrating the contributions from many more nanowires, we have successfully boosted the output of our nanogenerator enough to drive devices such as commercial liquid-crystal displays, light-emitting diodes and laser diodes,” said Wang, a Regents’ professor in Georgia Tech’s School of Materials Science and Engineering. “If we can sustain this rate of improvement, we will reach some true applications in healthcare devices, personal electronics, or environmental monitoring.”

Recent improvements in the nanogenerators, including a simpler fabrication technique, were reported online last week in the journal Nano Letters. Earlier papers in the same journal and in Nature Communications reported other advances for the work, which has been supported by the Defense Advanced Research Projects Agency (DARPA), the U.S. Department of Energy, the U.S. Air Force, and the National Science Foundation.

“We are interested in very small devices that can be used in applications such as health care, environmental monitoring and personal electronics,” said Wang. “How to power these devices is a critical issue.”

The earliest zinc oxide nanogenerators used arrays of nanowires grown on a rigid substrate and topped with a metal electrode. Later versions embedded both ends of the nanowires in polymer and produced power by simple flexing. Regardless of the configuration, the devices required careful growth of the nanowire arrays and painstaking assembly.

In the latest paper, Wang and his group members Youfan Hu, Yan Zhang, Chen Xu, Guang Zhu and Zetang Li reported on much simpler fabrication techniques. First, they grew arrays of a new type of nanowire that has a conical shape. These wires were cut from their growth substrate and placed into an alcohol solution.

The solution containing the nanowires was then dripped onto a thin metal electrode and a sheet of flexible polymer film. After the alcohol was allowed to dry, another layer was created. Multiple nanowire/polymer layers were built up into a kind of composite, using a process that Wang believes could be scaled up to industrial production.

When flexed, these nanowire sandwiches — which are about two centimeters by 1.5 centimeters — generated enough power to drive a commercial display borrowed from a pocket calculator.

Wang says the nanogenerators are now close to producing enough current for a self-powered system that might monitor the environment for a toxic gas, for instance, then broadcast a warning. The system would include capacitors able to store up the small charges until enough power was available to send out a burst of data.

While even the current nanogenerator output remains below the level required for such devices as iPods or cardiac pacemakers, Wang believes those levels will be reached within three to five years. The current nanogenerator, he notes, is nearly 100 times more powerful than what his group had developed just a year ago.

Writing in a separate paper published in October in the journal Nature Communications, group members Sheng Xu, Benjamin J. Hansen and Wang reported on a new technique for fabricating piezoelectric nanowires from lead zirconate titanate — also known as PZT. The material is already used industrially, but is difficult to grow because it requires temperatures of 650 degrees Celsius.

In the paper, Wang’s team reported the first chemical epitaxial growth of vertically-aligned single-crystal nanowire arrays of PZT on a variety of conductive and non-conductive substrates. They used a process known as hydrothermal decomposition, which took place at just 230 degrees Celsius.

With a rectifying circuit to convert alternating current to direct current, the researchers used the PZT nanogenerators to power a commercial laser diode, demonstrating an alternative materials system for Wang’s nanogenerator family. “This allows us the flexibility of choosing the best material and process for the given need, although the performance of PZT is not as good as zinc oxide for power generation,” he explained.

And in another paper published in Nano Letters, Wang and group members Guang Zhu, Rusen Yang and Sihong Wang reported on yet another advance boosting nanogenerator output. Their approach, called “scalable sweeping printing,” includes a two-step process of (1) transferring vertically-aligned zinc oxide nanowires to a polymer receiving substrate to form horizontal arrays and (2) applying parallel strip electrodes to connect all of the nanowires together.

Using a single layer of this structure, the researchers produced an open-circuit voltage of 2.03 volts and a peak output power density of approximately 11 milliwatts per cubic centimeter.

“From when we got started in 2005 until today, we have dramatically improved the output of our nanogenerators,” Wang noted. “We are within the range of what’s needed. If we can drive these small components, I believe we will be able to power small systems in the near future. In the next five years, I hope to see this move into application.”

Story Source:

The above story is reprinted from materials provided by Georgia Institute of Technology Research News. The original article was written by John Toon.