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Gold Nanoparticles Turn Trees Into Streetlights
An anonymous reader writes "Street lights are an important part of our urban infrastructure — they light our way home and make the roads safe at night. But what if we could create natural street lights that don't need electricity to power them? A group of scientists in Taiwan recently discovered that placing gold nanoparticles within the leaves of trees causes them to give off a luminous reddish glow. The idea of using trees to replace street lights is an ingenious one — not only would it save on electricity costs and cut CO2 emissions, but it could also greatly reduce light pollution in major cities."
I welcome our reddish glowing leafy overlords.
The world's burning. Moped Jesus spotted on I50. Details at 11.
Make it occur naturally.
Or rather - aren't there some kinds of mushrooms and other flora that glow in the dark? Why not just splice that plant with a tree. I know, I use the term splice like its an easy task.
Yeah because mining gold and refining it and the turning it into nano-particles takes zero energy....
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
I'd be chopping down trees everywhere!!!!
Nah, I know the particles are so small it would make the effort a waste of time. That aside, on a serious note, what happens to the "streetlights" when the Fall comes each year?
StarTrekPhase2 - The Five Year Mission Continues!
The nice thing about street lights, though, is that they don't fall off every autumn.
A group of scientists in Taiwan recently discovered that placing gold nanoparticles within the leaves of trees, causes them to give off a luminous reddish glow.
Even better, a group of US capitalists has discovered that setting fire to the trees produces an even more luminous glow, at no cost to the company, keeping the gold available for executive bonuses.
To summarise the summary of the summary: people are a problem. ~ h2g2
When I was a kid, sprinkling heavy metals around was considered a bad thing.
My, how times change.
-Peter
I can see at least one problem with this idea...
Necron69
So it appears as though the effect requires an outside energy source to be useful. Nothing to see here, move on.
Dog is my co-pilot.
I am speaking strictly out of self-interest here when I say this would be incredibly awesome.
As someone who's family has been in the tree business for a few generations, I would love our products to have a new utility that people actually see as practical. Currently, not many consumers understand that trees are not just for aesthetics, but can provide many practical benefits. Make 'em light up and people (municipalities, really) will be all over 'em.
Someone flopped a steamer in the gene pool.
> but it could also greatly reduce light pollution in major cities.
By replacing street lights with a different kind of street light? One without an apparent "off" switch?
It would seem to make more sense to just reduce the number of lights, or make them smart enough to be on-demand.
Log in or piss off.
The article says:
...A lot of light emitting diode, especially white light emitting diode, uses phosphor powder to stimulate light of different wavelengths. However, phosphor powder is highly toxic and its price is expensive. As a result, Dr. Yen-Hsun Wu had the idea to discover a method that is less toxic to replace phosphor powder. ...
By implanting the gold nanoparticles into the leaves of the Bacopa caroliniana plants, the scientists were able to induce the chlorophyll in the leaves to produce a red emission. Under a high wavelength of ultraviolet light, the gold nanoparticles were able to produce a blue-violet fluorescence to trigger a red emission in the surrounding chlorophyll.
So it sounds like the trees need a "high wavelength of ultraviolet light" to get them to glow. Seems like they are just replacing the phosphor that makes a white LED glow with these gold implanted leaves. But you'd still need a UV light source (which could be an array of UV LED's?).
I'm not sure that this is really an environmental win -- replacing an array of white LED's that last 10 years with an array of UV LED's that point to trees that need their leaves to be impregnated with gold (and replaced annually?) doesn't sound all that environmentally friendly. How bad is the LED phosphor for the environment?
Once again, proof that journalists should just stick to describing the research rather than coming up with groundbreaking applications which, as you'd almost certainly expect, don't work. The nanoparticles don't make the leaves glow "naturally", you have to shine UV light on them. Then they fluoresce red. But if you want to light streets using this technology, can I recommend just coating the UV light with leaves and doing away with the tree (we don't want to waste UV light after all)? In fact, ignore the leaves - just use a fluorophore. Actually, better yet, why not use a fluorophore that doesn't emit red light? How about something more akin to natural light, like yellow? And make it sensitive to blue light rather than UV (because generating UV is harder). And finally, while we're at it, make the light source solid-state.
Congratulations, you've just invented the white LED.
They are shining an ultraviolet light on the trees, with the gold particles they are glowing red by transforming the ultraviolet to red light.
neat, but kinda useless as ultraviolet is dangerous. (not useless on a small scale; but you can't go and light up a neighbourhood with ultraviolet)
But, I also likes savings the electricity
I swear to God...I swear to God! That is NOT how you treat your human!
Valar call prior art!
Ezekiel 23:20
"...not only would it save on electricity costs and cut CO2 emissions, but it could also greatly reduce light pollution in major cities."
What a stupid thing to say. If they provide enough light to replace street lights, then they contribute just as much to light pollution as the street lights do.
Unless and until we switch over to electric cars en masse, street lights are NOT wasting electricity.
One of the two primary purposes of street lights is to consume the power generated by base-load powerplants that mu$t spin 24/7. Without our vast numbers of street lights, night-time voltages would rise above 130 and start frying your appliances.
Ever wondered why the electric company does not charge money, if you ask them to add a street light to the pole near your house? That's the reason.
FATMOUSE + YOU = FATMOUSE
To generate the extra CO2 we could always burn some trees.
Maybe we could use these super-bright trees with some magnifying glasses to start the fires. Then not only does it save billions of dollars per second in electricity costs, but it is also self-sustaining.
Wait a minute. We could use the light from the super-bright trees to grow more trees! Then we'll have so much extra energy... Maybe we could use it to power fusion devices that turn lead into gold. My god... I think we have the makings of a perpetual motion machine here, one that for once doesn't break any laws of thermodynamics.
Everything about this story makes sense!
How does the tree feel about all this?
Seriously, is this healthy for the tree? More to the point, can you get the tree to grow with this feature as a natural part of it's genetic makeup?
Sorry to sound cynical but this sounds like another one of those "news" stories that exist solely to get attention, not because it's about anything really practical.
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
If you tell them the leaves are full of gold nanoparticles, I guarantee you that the leaves won't make it to autumn. Heck this is much easier than stealing copper from a utility pole.
But don't worry, the Bacopa caroliniana plant they mention isn't a tree, it's a little herb no taller than 50cm and oh, it usually only grows underwater. Instead of lighting up cities possibly they can light up your aquarium. Long way to go before showing this can actually work in trees...
Seven puppies were harmed during the making of this post.
We know that silver does this. I've always wondered what gold would do.
The interesting thing about "Infinities", is that they are not all created equal.
Take for instance, these two infinite sets:
All even numbers.
All numbers divisible by 4.
the first one is provably larger than the second, while both are infinite quantities. (In fact, the second is a provable subset of the first.)
This is why "Infinity" is not a "Value".
This is usually where my head starts to wobble, but if you can have two unequal infinities, doesn't that mean that they have different values?
See? Right there. Now there's blood coming out of my left ear. This abstract thought stuff is dangerous for me.
You are welcome on my lawn.
Infinity isn't a number.
Right
If anything, the concept represents a "really really big positive number" in this context, in which case, yes, if you add something greater than 0 to that really really big number, then you will have an even bigger number.
If I remember, and understood, my college math properly:
In mathematics, k+inf. is inf. but you wouldn't represent it that way. It would probably be a limit. So the limit of a+k as a approaches infinity is infinity. Are they the same?
You could consider the limit of (a+k)/a as a approaches infinity, this limit is 1 so it would appear to be the same.
If you consider the limit of (a+k)-a as a approaches infinity then the limit is k so it would appear that they are different.
So I don't think you can say whether they are the same or not but, within some contexts, you could consider them to be the same or different based on that context.
IANAM