Fresh Greens: Better LEDs from Salmon (yep, the fish), Vegetarian Killer Robots, and More Green Oddities
Each week we're bringing you some of our favorite posts from our friends over at TreeHugger. Enjoy!
Fish are the Secret Sauce for Better LEDs
What happens when you mix fluorescent dyes with salmon DNA? Awesome lighting!
Killer (Veggie) Robots for the Military
It can drive and feed itself, but veggie style. We aren't that ready to go Terminator yet.
Australians + Bikes + Hip-Hop Videos = Hilarity
Would you ditch the car and hop on a fixie after seeing this video?
Ginormous Solar Flowers with Free Wi-Fi Taking Over US Cities
Six lucky cities will get some ridiculous looking solar flowers for a little free wi-fi and rest time. Is your city on the list??
the latest
latest episodes
manshonjaggers? Fighting Trees ought to be a priority.
and those wifi antennae should be silvered, a sort of Tnuctipun inspired anti-litter measure.
Other than in the post title, i don't see a reference to salmon anywhere in the article... Maybe my crtl+F isn't working.
The latest breakthrough comes from the University of Connecticut, and it uses salmon DNA to create very long-lasting white LEDs (though they can be tuned to other colors). Read on for more details.
slashdot
"Researchers from the University of Connecticut have created a new light-emitting material by doping spun strands of salmon DNA with fluorescent dyes. The material, which is robust because DNA is such a strong polymer, absorbs energy from ultraviolet light and gives off different colors depending on the amounts of dye it contains. A team led by chemistry professor Gregory Sotzing created the new material by mixing salmon DNA with two types of dye, then pumping the solution from a fine needle while a voltage is applied between the needle tip and a grounded copper plate covered with a glass slide. As the liquid jet comes out, it dries and forms long nanofibers that are deposited on the glass slide as a mat. The researchers then spin this nanofiber mat directly on the surface of an ultraviolet LED to make a white-light emitter. The color-tunable DNA material relies on an energy-transfer mechanism between two different fluorescent dyes, and the DNA keeps the dye molecules separated at a distance of 2 to 10 nanometers from each other."
"Researcher and scientists all over the world talk about eco-friendly, biodegradable materials, etc, and a new invention we can proud is LED from salmon sperm. What is salmon sperm and why they used it? Salmon sperm is considered a waste product of the fishing industry. It’s thrown away by the ton,” says Prof. Steckl, a leading expert in light-emitting diodes, is intensifying the properties of LEDs by introducing biological materials, specifically salmon DNA. Electrons move constantly — think of tiny particles with a negative charge and attention deficit disorder. It is through the movement of these electrons that electric current flows and light is created.
He thinks that besides salmon DNA, other animal or plant sources might be equally useful. Biological materials have many technologically important qualities — electronic, optical, structural, magnetic,” says Steckl. “But certain materials are hard for to duplicate, such as DNA and proteins.”
So began Steckl’s work with BioLEDs, devices that incorporate DNA thin films as electron blocking layers. Most of the devices existing today are based on inorganic materials, such as silicon. In the last decade, researchers have been exploring using naturally occurring materials in devices like diodes and transistors. “The driving force, of course, is cost: cost to the producer, cost to the consumer and cost to the environment” Steckl points out, “but performance has to follow.”
“The story continues,” says Steckl, again smiling. “I’m receiving salmon sperm from researchers around the world wanting to see if their sperm is good enough.” The next step is to now replace some other materials that go into an LED with biomaterials. The long-term goal is be able to make “green” devices that use only natural, renewable and biodegradable materials.
Can we imagine their long term goal, be able to make "green" devices that use only natural, renewable and biodegradable materials? So, if we can understand like I do what they mean, almost all gadgets do not need a batery to operate its which what they will do are manipulate proton to interact with photons.
Source : Cincinnati
Somebody apparently thought it was cool that technology was going to Ma Nature for help, but the real useful content in this article is actually pretty thin.
This might be a good time to point out that the idea of LEDs for illumination is still kind of wrongheaded.
Despite years of research and some well-publicized developments, white LEDs are just now reaching and, in the laboratory, now and then even bettering the efficiency of a good fluorescent light. None of them can yet come close to matching fluorescents for cost per lumen and it's going to be many years before they can.
LEDs are great for brightness, not so much for actual light output. (They're not the same thing; look it up.) So they excel as indicators - the LEDs on your computer, in car taillights, and in traffic lights.
They're also a good choice for dim lighting (night lights and such), because in low wattages, ballast losses dominate with fluorescents. And they're good for use on batteries because they *like* low voltage, whereas fluorescents don't.
The problem is that unlike fluorescents and incandescents, you can't make LEDs big. So to get useful amounts of illumination from them, you have use lots of them, and increase each one's output to perilous levels. This is kind of like replacing your car's battery with a bunch of 9 volt transistor batteries. You might be able to make it work, but it's going to be awkward and inefficient.
Take an LED headlight, for example. In order to get enough light from a small package, they really pack in the emitters. That makes heat a problem. Or rather it makes *getting rid* of the heat a problem.
If you're thinking that LEDs are supposed to be efficient so heat SHOULDN'T be a problem, you're thinking along the right lines. Many people have the idea that LEDs don't produce any heat at all, but of course they do. The tiny ones don't produce perceptable heat, but then their light output is tiny. When you're trying to match the output of a 50 watt incandescent, you're going to have substantial amounts of waste heat.
Don Klipstein has a webpage that explains much of this in more technical detail. Read it.
http://members.misty.com/don/lede.html
Someday we may see LED lighting that's truly practical and efficient. But not yet.
And somehow I suspect that if this were the breakthrough that we've all been waiting for, the researchers would be shouting about its efficiency instead of staying mum.
BTW, for the record, I do *not* work in the lighting industry. I'm just interested in efficient lighting and I follow this stuff closely. In my home LEDs are night lights and indicators, and all the room lighting (yes, ALL) is fluorescent. LEDs there too? Someday, I hope, but I'm thinking decades, not years.
Why do hippies make bike culture look so shit? On a similar note why does all nearly all Aussie hip-hop suck quite so hard?
Who wants to start a hip-hop crew in Melbourne? I can't rap but I'll pop out some fresh hip-hop beats bass guitar/loop pedal style..