In today's edition:
- Plumbing the oceans could bring limitless clean energy
- First superconducting transistor promises PC revolution
- New Technology Could Power Laptop For Days
- First light for US 'laser jumbo'
Plumbing the oceans could bring limitless clean energy
- 19 November 2008 by Phil McKenna
Commercial Ocean Thermal Energy Conversion (OTEC) plants exploit the difference in temperature in seawater
In September, the Department of Energy awarded its first grant for ocean thermal energy in more than a decade, giving Lockheed Martin $600,000 to develop a new generation of cold water pipes.
Cohen believes this could eventually lead to 500 MW OTEC plants on floating offshore platforms sending electricity to onshore grids via submarine cables, and factory ships "grazing" the open ocean for power.
While Lockheed gears up for its test facility in Hawaii, a plant for the US military could come online even sooner. OCEES International, based in Honolulu, is finishing designs for an ocean thermal facility to be built off the island of Diego Garcia in the Indian Ocean, which is home to a major US military base. source
My comment: Funny how much love there is between Lockheed Martin and the US government. But in the case, I think it's not so bad. After all a working OTEC will make many people very happy. Not to mention that no matter how successful the project is, it is an investment in the science. Whatever they discover, we'll profit all.
First superconducting transistor promises PC revolution
- 03 December 2008 by Paul Marks
Last year Andrea Caviglia and his colleagues at the University of Geneva in Switzerland grew a single crystal containing two metal oxides, strontium titanate and lanthanum aluminate, as separate segments. At the interface of these materials, the team found a layer of free electrons called an electron gas (Science, vol 317, p 1196) that are superconducting at 0.3 kelvin.
Now the same group says it can switch this superconductivity on and off by applying a voltage to the interface. The result is a superconducting version of the field effect transistor (FET).
The speed at which a FET can switch is limited by the resistance of the channel, which creates heat. Higher speeds create more heat until eventually the device burns out. That's why a superconducting FET could run much faster.
Caviglia's team made such a transistor by using the lanthanum aluminate side of its crystal as a source-drain channel and the strontium titanate layer as the gate (Nature, vol 456, p 624). Applying an electric field to the strontium titanate, the dense electron gas gets shifted away from the interface and the lanthanum aluminate stops conducting current.
Caviglia said that computers using such transistors would be "much faster than the gigahertz speeds currently available". source
My comment: Cool. Literally :) Seriously, if that gets practical, it will do miracles for computers. But if we must be realists, 0.3K isn't a temperature you'd enjoy having in your room. It's very very cold. Until they get the effect in room temperature, it won't do much good to pc users.
New Technology Could Power Laptop For DaysSIOUX FALLS, S.D., Dec. 1, 2008
(AP) Laptop, cell phone and iPod owners tired of having their devices run out of charge after a few hours have been patiently waiting for the next portable power source to arrive.
Tiny fuel cells, powered by combustible liquids or gasses, have long been touted as the eventual solution. Potentially, they could power a laptop for days between refills.
But fuel cells have perennially remained a year or two away from reaching the market as companies have worked on making them small, cheap and long-lasting, while making sure they don't overheat.
The U.S. government removed a key roadblock this year when the Department of Transportation amended its hazardous materials regulations to allow cells with methanol, butane or formic acid to be carried on airplanes. Methanol and butane are flammable, and formic acid is corrosive.
Fuel cells, in which a tiny amount of fuel flows into a small chip to generate electricity without combustion, would allow users to skip the wall plug and simply swap out a fuel cartridge to continue listening to music or check e-mail.
Bradford thinks products are now truly a year or two away, as electronics manufacturers show more interest and fuel cell makers move beyond trade-show prototypes.
Lilliputian Systems Inc., a Wilmington, Mass., firm founded by former Massachusetts Institute of Technology researchers, plans to introduce a portable fuel cell cigarette-pack-size late next year for any device that can be charged via a USB port.
The charging system would likely sell for $100 to $150 with refill cartridges retailing for $1 to $3, he said. source
My comment: Nice. But until I see it hitting the market, I won't believe it's done. Let's face it- there are many obstacles to the commercial realisation. Not to mention how unsufficient 20 hours actually are. But it's a step forward, of course. Currently, on full CPU speed, my notebook lasts for 40 minutes. I don't mind expanding a lot this time!
First light for US 'laser jumbo'
The US military has carried out the first test-firing of a laser weapon system housed aboard a 747 plane.
The Airborne Laser (ABL) was conceived to shoot down enemy ballistic missiles in the early stages of their flight.
Engineers conducted the test on the ground, firing the laser out through a turret mounted on the nose of the plane at a simulated target.
An airborne intercept of an in-flight ballistic missile is planned for 2009.
The multi-billion dollar ABL programme has been running for more than 12 years.
Scientists are reported to be working out other uses for the flying weapon - which could help secure continued funding. These extra missions include shooting down surface-to-air missiles, cruise missiles and even enemy aircraft.
The latest ground test was carried out by the US Missile Defence Agency at Edwards Air Force Base in California.
A laser beam travelled the length of the aircraft at one billion km/h (670 million mph).
It raced from the aft (back) section that houses the laser, through the beam control and fire control system, and out through the nose-mounted turret.
When the laser beam emerged from the aircraft, it was captured by a diagnostic system which also provides simulated targets for the laser.
The next step is to carry out some long duration firings of the laser.
The ABL is designed to illuminate an enemy missile with a laser tracking beam, while computers measure its distance and calculate its course and direction.
After acquiring and locking on to the target, a second, high-power laser fires a three-to-five-second burst from the turret in the 747's nose.
The beam heats up the pressurised fuel tank of the outbound missile and causes it to rupture, destroying the missile.
The high-energy weapon is a Chemical Oxygen Iodine Laser (COIL) capable of producing megawatts of power.
Built by defence giant Northrop Grumman, it is designed to destroy "all classes" of ballistic missiles, including tactical ballistic missiles (TBMs) and intercontinental ballistic missiles (ICBMs).
Destroying ballistic missiles during their boost phase - while their rockets are firing - carries several advantages- due to the exhaust heat, they are easily detectable, it is much more difficult to use countermeasures, such as decoys, during this phase of flight and the wreckage will usually land in enemy territory.
The range for a typical liquid-fuel intercontinental ballistic missile (ICBM) is up to 600km away, but for solid-fuel ICBMsis about 300km.
This would be too short to defend against solid-fuel intercontinental ballistic missiles launched from Iran or North Korea, the US report explained. source
My comment: Great news for the crazy for fights people. Not so great for those who will stand on the way of the laser. But in any case, it will be pretty useful for space fights and for clearing up stuff in vacuum-which could have a peaceful use also.