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The Amazing Properties of Aerogel
RideMax writes "We all know NASA is using a substance called 'aerogel' in the Stardust spacecraft to catch pieces of the Wild-2 comet. The NYT is running an article about some other amazing aerogel properties. My favorite quote: 'It's the lowest density of any solid, and it has the highest thermoinsulation properties. Though it would be very expensive, you could take a two- or three-bedroom house, insulate it with aerogel, and you could heat the house with a candle. But eventually the house would become too hot.'" We've looked at Aerogel before.
I think Mr. Kelley has done a masterful job describing modern day industrial design in terms and examples we can all relate to. He makes it clear why innovation in our high tech world is as much art as science. And why his company delivers 'marketable products' for their clients and not 'products looking for a market'. I think there are lessons here for a wide spectrum of engineers, marketeers, and anybody responsible for a (successful!) product or service coming to market. The book is interesting and fun to read.
Though it would be very expensive, you could take a two- or three-bedroom house, insulate it with aerogel, and you could heat the house with a candle.
Seems to me that in this case, having a few lights left on or PC with a hot CPU left running would quickly make things uncomfortable
What if it was only used to certain walls where leakage was most common?
- It is 99.8% Air
- Provides 39 times more insulating than the best fiberglass insulation
- Is 1,000 times less dense than glass
- Was used on the Mars Pathfinder rover
And a cool picture of aerogel in somebody's hand.--
For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.
Seems like quite a few successes are discovered by mistake.. in this instance, finding a rejected material from nuclear testing.
It also has incredible compressive strength. "It can take 2,000 times its body weight without damage," Dr. Tsou said. NASA's Web site shows a 2-gram cube of aerogel (less than 0.1 ounce) supporting a 2.5-kilogram brick (about 5.5 pounds).
That particular example doesn't seem that impressive, I used to build balsa wood structures that would hold over 600 lbs(~270kg), with only 15 grams of balsa wood and glue, with strict rules on how it could be built. The world record is somewhere in the 1500 lb mark with a similar weight of wood.
Nobody cares about your Odyssey of the Mind days. That ratio is actually pretty impressive for a solid material...imagine what it could hold if it used physics such as trusses and lamination, like you did.
I heard of Aerogel long ago, but I assume the issue is the same as then - price. Is it getting better, or is it still for those really really extreme projects only? It's cool in the same way superconductors are, but you don't get to play around with them...
Kjella
Live today, because you never know what tomorrow brings
Not sure if all Aerogels are created equally, but this is from 1999 NASA article on Aerogel:
"A single one-inch thick windowpane of silica aerogel is equivalent to the insulation provided by 20 windowpanes of glass (R-20 insulation factor)."
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For news, status, updates, scientific info, images, video, and more, check out:
(AXCH) 2004 Mars Exploration Rovers - News, Status, Technical Info, History.
let me get this straight....virtually unbelieveable insulation at the coldest of temperatures...creating super greenhouses/habitats and so forth...
improves the desalination of seawater plants a thousand fold...
my god....all we have to do is find a cheap or easier way to produce (like we do with virtually everything in the world in the free enterprise system) and we can offer virtually energy free habitats (excess heat can be channelled into electronics and solar can pick up the rest) - as well as a cheap water supply for the world...
christ...someone get me some chemists and a few venture capitalists.....this is incredible... - and it's real and now...not like those carbon nanofibers people want to use to create space elevators...
pax
RB
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ah honey, we're all resplendent - Bill Mallonee
The article doesn't touch on it, but the NASA FAQ mentions this unique property...
Q: What happens if I touch it?
A: Silica aerogel is semi-elastic because it returns to its original form if slightly deformed. If further deformed, a dimple will be created. However, if the elastic limit is exceeded, it will shatter catastrophically, like glass.
Some cool shots.
Here's a nerdy factiod about aerogel that might help your processor speed.
There has been some close research into using substances like aerogel to improve processor speeds. Apparently the substances can be used as very efficient insulators between traces and components. This is because aerogel and substances like it are mostly made of air, which has a very high dielectric constant so aerogel itself is a very good insulator.
It's better described here
While I'm sure aerogel has many pracitcal uses (trying not to fall asleep here), the "cool" factor is also very high. I've seen some of her samples, and everything the article says is correct. It's so light it feels like the wind could take it; in fact, if you drop it in water, I think it dissolves. Since the material is so expensive, it's obviously something you don't want to do, since every last piece is precious.
As you might imagine, a material that's ultra-light and 'holographic' has artistic applications, too. The "brain" image made it onto the cover of Nature neuroscience, and wouldn't look out of place in a design magazine. When you see it up close, the image seems to be 'embedded' in the material, even though it's so light you could easily crush it with your hand. The airiness and delicacy of the material makes the image that much more striking.While we're all attuned to the utilitarian value of materials like this, it's always neat to see what people outside of engineering can do with them.
For those of you who like stupid science tricks/supercheap climate control, here's a trick for how to heat and cool a house without using any energy (outside of what's free from the Sun):
/ blackbody/bbody.html), which gives 300-500W/m^2 at typical Earth temperatures (over 400W/m^2 heat loss at typical room temperature).
First, some background on black body radiation. All matter radiates some light, based on its temperature. By basic thermodynamics, the amount of radiation that a color of matter absorbs in a given frequency range (as opposed to reflects) is directly proportional to how much it radiates (as compared to a perfect black body of the same temperature).
The sun only radiates on a fairly small set of frequencies, and that set is very different from the frequencies at which a black body at room temperature radiates. If you build a panel of a material that is perfectly absorbent in the frequencies on which the Sun radiates (perfect black body), but reflects in the remaining frequencies (perfectly white on the blackbody frequencies of room temperature), it will lose very little heat to radiation, but absorb a lot from the sun, and it'll get very hot. If you take a body that reflects radiation in the colors the sun emits (white), but absorbs/radiates elsewhere (black), it'll get very, very cool, even in bright sunlight. You can get pretty close to the full 1000W/m^2 of heating (level of Sun's radiation hitting the earth). In cooling, you get pretty close to the ideal from Stefan's Law (http://www.egglescliffe.org.uk/physics/astronomy
This means that you can theoretically heat or cool a house with just a painted square on the roof a few square meters in area, if you could just create a material of the right color.
Problem is the guy who came up with this (and showed it to me) was a physicist and not a chemist, and had no idea how one would go about creating a material whose color was that well controlled.
Still a nifty concept, eh? If you could make this, it would save a ton of energy, since you'd no longer need to burn gas to heat and use electricity to cool -- just flip a panel on your roof, and the temperature changes (although for heating, the house would need to be well enough insulated to last the night).
Ref: The Third Industrial Revolution by G. Harry Stine.
See CDT Water for one practical, functional application of aerogel.
In short, they push contaminated water through aerogel and use electrodes to pull ionic molecules apart. The ions get caught in the aerogel mesh, and the purified water flows through. At least, that's my layman's understanding of it.
Cheers
-b
If I wanted a sig I would have filled in that stupid box.
Maybe I'm missing something, but elsewhere they said "But, Dr. Tsou said, the material was not used much, except in powdered form as a nontoxic anti-caking agent for food."
If it's so expensive, what kind of food exactly were they using it on? Caviar?
This Space Intentionally Left Blank
It might not be flexible, but it's very light. If it can catch dust flying at 14,000mph, surely this would be the perfect material for a bulletproof vest.
I ran a benchmark on my quantum computer, now I can't find it anywhere!
A few years later, Kistler left the College of the Pacific and took a position with Monsanto Corp. Shortly thereafter, Monsanto began marketing a product known simply as "aerogel". Monsanto's Aerogel was a granular silica material. Little is known about the processing conditions used to make this material, but it is assumed that its production followed Kistler's procedures. Monsanto's Aerogel was used as an additive or a thixotropic agent in cosmetics and toothpastes. Very little new work on aerogels occurred throughout the next three decades. Eventually, in the 1960s, the development of inexpensive "fumed" silica undercut the market for aerogel, and Monsanto ceased production.
--- source
Oooh ahhhh, I'm so leet. A friend at work had a few samples of the stuff a couple years ago. I recall that although it was extremely light, it fell quickly when I dropped it from hand to the other. These were small pieces, about an inch on a side, so they had little frontal area for their mass. I suspect that a typical birthday balloon weighs even less than the same volume of aerogel. Another thing was that they were quite fragile, and absolutely rigid. I did not break any, but it was obvious that I could crush it into dust if I squeezed just a little too hard. After handling it, I had some miniscule crunchy particles on my skin, and probably a lot more I couldn't see, and I got the sense that going without a respirator if you worked with the stuff would not be a good idea. If I'd had a blowtorch handy and a big enough chunk of aerogel, I'd have been unable to resist doing the blowtorch-against-the-hand trick.
IR-invisibility cloak. Just wear it and be hidden from all IR eyes in the sky... neat.
Could aerogel be formed with some other gas other than air, like pure hydrogen? Would it become lighter than air then and float around?
Just a thought, maybe some slashdotter knows, I've read the aerogel facts from the JPL page but it doesn't mention anything about this.
~~~Please pass the salt, I hate unsalted MD5s
For several years at Disneyland, they've had a sample of it in FutureLand or TomorrowLand or whatever it's called. Sort of across the path from Star Tours, there is a whole exhibit about the US Space Program. Inside a glass case, they have a square of Aerogel held up. Unfortunately, they don't let you touch it or anything. But it is interesting to look at - it's hard to find the edges of the material, even when you are concentrating.
-If
Run a pencil-and-paper RPG campaign with your far-off friends: Gametable!
You forgot to mention the reason for using Aerogels as Cherenkov detectors: they present very little mass, so low-mass particles will not interact and/or deposit much energy in them (e.g., for electrons the Aerogel will act only as a Cherenkov detector and not a calorimeter). The only other real alternative for getting indices of refraction barely over 1.0 is to use pressurized gases, which present a whole series of their own problems.
Diatomaceous earth is 100% natural microscopic glass shards. Being microscopic glass shards they are an excellent insecticide. The shards pierce the insect's shell and through capilarry action, they suck out all the internal fluids drying the bug to a corpse. However, the shards are so small that humans can ingest them without fear of harm.
So if you have a garden, or some veggies or other food you want to protect from insect pests without using a substance toxic to humans and pets, sprinkle on a little diatomaceous earth. Better yet mix up some garlic powder, water and diatomaceous earth in a bottle and spray it on. Garlic kills bugz too w/o being dangerous for ppl.
Eat at Joe's.
This means that you can theoretically heat or cool a house with just a painted square on the roof a few square meters in area, if you could just create a material of the right color.
:-)
Ummmmm... I'm afraid that at least with respect to heating, it's been done: glass is transparent in visible light but opaque at room-temperature black body radiation frequencies, aka infrared. It's called the greenhouse effect, and it heats my wintergarden just fine.
Another great patent idea lost to public-domain prior art - doh!
- nic
Be faithful to your obsessions. Identify them and be faithful to them, let them guide you like a sleepwalker. JG Ballard
On a more serious note, I wonder if this stuff has any radiation shielding properties? When they fired particles into the gel, they were very quickly stopped. And placing the gel against a bunsen burner doesn't even phase it. If it protects against radiation just as well, its light weight may make it the perfect space ship shielding material.
Javascript + Nintendo DSi = DSiCade
I believe that the density is measured by the volume of the cube divided by the mass of the cube. (In many cases it's also motioned that 98.8% of an aerogel is empty space.) But keep in mind that the truly remarkable feature about this is the scale at which this occurs.
The framework that makes up an aerogel is so fine that the individual components are around 3-5 nanometers in thickness. (An atom is about 0.1nm).
In your aluminum example the average density of the space defined by the cube would be less dense. But the foil that makes up its walls is easily discernable from the air. It might be easier to think of an aerogel like a sponge, or angel food cake where there are tunnels of air (or empty space if you'd rather) in the material. But in the case of the aeogel the tunnel are microscopically small complex in shape.
..of ships and shoes and sealing wax, of cabbages and kings.