October 1, 2006 Researchers at the ETH Chair for Power Electronics have developed an electrical generator that spins at a world record 500,000 revolutions per minute (RPM) and scientists are hopeful they can achieve twice this speed to touch the magical million rpm. The matchbox-sized motor generates the equivalent of 100 watts, including the power electronics interface, and has an efficiency of close to 95 percent. Powered by a gas turbine, one tankful of fuel drives the generator for about 10 hours at peak 100 watt performance. These ultra small gas turbines could replace conventional batteries as a mobile power source and have a range of potential applications, from dentistry where ever smaller holes could be drilled with ever higher rotation speed through to energy supply for mobile applications, such as portable heart-lung machines or artificial hearts. The little motors could also be used in turbo compressors, which condense gas mixtures or air.
A US state is to enlist web users in its fight against illegal immigration by offering live surveillance footage of the Mexican border on the internet. The plan will allow web users worldwide to watch Texas' border with Mexico and phone the authorities if they spot any apparently illegal crossings. Texas Governor Rick Perry said the cameras would focus on "hot-spots and common routes" used to enter the US. US lawmakers have been debating a divisive new illegal immigration bill. The Senate has approved a law that grants millions of illegal immigrants US citizenship and calls for the creation of a guest-worker programme, while beefing up border security. But in order to come into effect, the plan must be reconciled with tougher anti-immigration measures backed by the House of Representatives, that insist all illegal immigration should be criminalised. The issue has polarised politics and US society. Right-wing groups have protested against illegal immigrants, while ...
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