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Shark

Researchers Demonstrate the World's First White Lasers 118

An anonymous reader writes: Scientists and engineers at Arizona State University, in Tempe, have created the first lasers that can shine light over the full spectrum of visible colors. The device's inventors suggest the laser could find use in video displays, solid-state lighting, and a laser-based version of Wi-Fi. Although previous research has created red, blue, green and other lasers, each of these lasers usually only emitted one color of light. Creating a monolithic structure capable of emitting red, green, and blue all at once has proven difficult because it requires combining very different semiconductors. Growing such mismatched crystals right next to each other often results in fatal defects throughout each of these materials. But now scientists say they've overcome that problem. The heart of the new device is a sheet only nanometers thick made of a semiconducting alloy of zinc, cadmium, sulfur, and selenium. The sheet is divided into different segments. When excited with a pulse of light, the segments rich in cadmium and selenium gave off red light; those rich in cadmium and sulfur emitted green light; and those rich in zinc and sulfur glowed blue.

Comment Re:Scary? (Score 2) 63

Now if only video ads in general caused epileptic seizures, so we could get them banned too.

Sadly, for me, they only trigger an irresistible desire to close that browser tab.

Sure - I understand a website that is providing interesting content for free has to have advertisement to support it - and I am mostly ok with that - I just wish it was static text and pictures, instead of bloody annoyingly intrusive video ads.

Comment Re:It only works without humans (Score 5, Insightful) 503

Greed is infinite, and is ultimately about power and control. If it were possible, I am sure there would be those who would own the entire galaxy, if for no other reason that to say it's theirs.

Even now, you have executives that earn multi-million dollar salaries, with super yachts and homes that they use for a fraction of the year. What's the point? There is little additional benefit from having a 100 ft yacht compared to a 200ft yacht, but there is a huge difference in the money you have to have to pay for them.

All those dollars have been paid to a single executive to afford such things has been done so instead of making goods and services cheaper for the customer, or by paying better salaries to the rest of the company's employees.

Executive salaries in the 60s were typically 25x the average salary.
Now they are more than 200x the average salary. More efficient production is not going to change this.

Comment Re:Cycles are too cheap (Score 1) 56

I sell my excess solar back to the grid at a rate which is a really bad deal for me - only 6c per kWh, which is al any of the utilities will pay for it
I expect selling my 'spare' computing cycles will be a similarly crap deal.
One day I hope there will be an energy storage solution which will allowe me to better usilise this excess solar capacity.
Meanwhile, I switch offwhatever cpu's I don't actually need running, so there aren't really any spare cycles to be had, and if there were, I wouldn't want to burn the electricity needed to spin them.

Comment Re:No, not practically, no. (Score 1) 124

Supermarket and shopping mall car parks are the perfect place for charging. Around here, it gets pretty bloody hot and sunny during the day, and getting back into your car after doing the shopping is a less than pleasant experience.
  Supermarkets are already getting into the fuel business here with shopper docket discounts on petrol, so it would be a logical extension for them to shade car parks with solar panels that charged your car while you were shopping. It would give them an instant competitive advantage over rivals, or alternatively could create a new revenue stream, all while allowing them to rightly claim they were helping "save the planet"

Comment Re:Even simpler (Score 1) 114

I have replaced all my halogen down lights , 50w each, with LED lights that use only 5w, and actually provide better light.
I typically have 15 on, 4 hours a day.
As a proportion of my overall power usage, my lighting has dropped from about 15% to 1.5%
The LED bulbs will last longer (10,000 hours) than halogens, and pay themselves off in terms of saved electricity, in 2 years.
Electricity is $0.26 /kwh here, and each bulb saves 0.045 kwh every hour it is being used.
it will take 777 hours for it to save it's own purchase cost in electricity, or approximately 194 days of typical 4 hours a day use.
Definitely worth while both economically and environmentally.
 

I'm all for computer dating, but I wouldn't want one to marry my sister.

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