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Graphene Aerogel Takes World's Lightest Material Crown
cylonlover writes "Not even a year after it claimed the title of the world's lightest material, aerographite has been knocked off its crown by a new aerogel made from graphene. Created by a research team from China's Zhejiang University in the Department of Polymer Science and Engineering lab headed by Professor Gao Chao, the ultra-light aerogel has a density of just 0.16 mg/cm3, which is lower than that of helium and just twice that of hydrogen."
Otherwise I think hydrogen still wins
I'm assuming that the 'density' figure given is a 'weight of graphene in a given volume' one, rather than one that includes the gasses occupying the pores/cells of the material?
It would be quite shocking indeed if something largely saturated in nitrogen and oxygen were less dense than helium...
I still remember the first time I learned about aerogel. The picture had a column of Aerogel about the size of a double-height coke can on one side of a balance and 3 M&Ms on the other side that weighed more.
Make a bag around it. Remove the air. We have an airship with the lift somewhere between H and He.
So how strong is the aerogel? How big a bag can we make and have it support atmospheric pressure on the other side? That will really determine the lift efficiency.
Obviously not 'lightest', but 'least dense'. Sheesh, editors - do your JOB! The /. title should be "Silly folk at Gizmag confuse mass with density when describing world's least dense solid.'
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
" the ultra-light aerogel has a density of just 0.16 mg/cm3, which is lower than that of helium and just twice that of hydrogen."
Picture in the article shows a chunk of the stuff being supported by a blade of grass. If the density's lower than that of helium, why isn't it floating away instead of sitting there like a thing that's denser than the atmosphere around it?
If the substance's density could be altered, it would be possible to have one membrane of gel that was more dense than helium and hydrogen, but less dense than every other element. Then have this gel, which is less dense than helium and more dense than hydrogen. Helium and Hydrogen would flow through the first membrane leaving everything else behind, and then only Hydrogen would pass though the second membrane leaving only helium trapped in between. Given the state of the world's current Helium reserves, this might be a very handy technology.
anti-China bashers go? the ones who keep saying China is a copycat while they weren't born in the70's and 80's when Japan was doing the exact same thing.
How is it made? The problem with the previous aerogel was it was rather expensive to make. It was also fairly fragile. So its applications for insulation made it a pain as it took lots of extra prep to make it is decent insulator. Is this any different? What sort of structural integrity does it have? Being light and probably a lattice which can 'absorb oil spills' I suspect not very good.
Insulating a house with this sort of thing would be amazing. However, the cost is also quite amazing. For example a guy I know built a house recently. It was cheaper to make the walls 1 inch thicker and stack up rigid foam with blown in insulation than to use some of these newer materials for the same R level.
Can be used to make the hardest or lightest stuff on the planet.
Carbon's reputation is however spoiled by a couple of Oxygen a-holes that like to latch on to it, stupid no good Oxygen.
I haven't thought of anything clever to put here, but then again most of you haven't either.
This stuff is lighter than helium (presumably at standard pressure and temperature) and yet not buoyant in air. That presumably means it's air-permeable in much the same way that a cellulose sponge is water permeable? In that case, in what sense is it lighter than helium? If you enclosed a volume of this stuff in a gas-tight membrane it would presumably be buoyant in air, but that - it seems to me - would surely be because vacuum is lighter than air?
I'm old enough to remember when discussions on Slashdot were well informed.
Graphene Aerogel Takes World's Lightest Material Crown
A crown should weigh heavy on a ruler's brow, lest he forget the weight of his responsibility.
What makes this so different from, say, creating a hollow cube with some very fine polymer for the vertices, with the faces and interior remaining empty? If something's full of holes, is its density still measurable in a meaningful way? A battleship is less dense than water in this sense, but the material it's made from isn't.
systemd is Roko's Basilisk.
But it will take years to figure out the dynamics of this matrix.
You sir, really need to get laid massively. Get a job and cut your hosts bullshit out. Nobody cares about your posts.
Here's my stupid question: if it's less dense than helium, and about 1/10 that of nitrogen (1.6 mg/cm3)...why is it pictured *sitting* on anything? Why doesn't it float away?
If, as I suspect, it's porous and it's being measured as 'less dense' than He only because they are taking the actual mass/OUTER VOLUME...well, that's not actual density is it? If so, then by this method my portable dog kennel (made of STEEL) is only an order of magnitude more dense than oxygen.
-Styopa
This thing seems to consist mainly of air. Doesn't that stretch the definition of "material" quite a bit? If I create a 10-foot wireframe cube consisting of just 12 thin aluminium stiffeners, and define the whole interior of the thing as part of the "material", that's gonna have a pretty low density too.
Since graphene is carbon and hence burns in oxygen, it might be interesting to saturate the matrix with oxygen instead of hydrogen.
It would then probably burn very nicely when ignited, the combustion spreading into the volume quite quickly from the surface. And if a detonator is used to shatter the fragile graphene then the mix would quite likely explode like a well-dispersed fuel-air bomb.
You replied to an impostor, dumbass. You can tell by the lack of formatting. He just copy/pasted.
I can change the density of hydrogen or helium by heating it up, or compressing it.
If I wanted hydrogen to be less dense than whatever aerogel, I just need to move the hydrogen to a bigger bottle.
The convention in the United States for decades has been to places periods inside the quotation marks. All others are based on the actual quote. The Chicago Manual of Style, as one of many, recommends this, but most guides point out that the British style placing anything not part of the quote outside of the quotation marks is acceptable but may be seen as unusual to American readers--of all ages.
Although putting periods inside quotation marks is recommended by various manuals of style and others recommend putting them outside, I believe that both approaches are misguided
Clarity should be the primary concern in language. Quotation marks are used to indicate that the current passage is repeating something verbatim from another source. It is most accurate to include punctuation inside quotation marks if that punctuation is repeated verbatim. In that case, they are punctuating the original. If they are not from the original source, they should be used outside.
http://yetanotherpoliticalrant.blogspot.com
The second problem is actually the main problem, IMHO. It is not like this kind of lifting agent is going to leak out if the hull is damaged by bad weather, or expand uncontrollably if ship ascends too abruptly.
The hull is damaged, air might leak in and make the structure heavier. The is short of design makes airship rather similar to ships and submarines that move through water. In the event of damage the worry isn't that the contained material (air in the case of ships and submarines) will leak out. The problems is that the outside material (water in the case of ships/submarines, air in the case of a aerogel filled airships) will leak in.
You are also assuming that the outside air pressure wouldn't crush it down to a density that would make it sink.
I would be really surprised if you could just evacuate the stuff and make it float. Some day we'll use evacuated carbon nanostructures for lighter than air, but I don't think we're there yet.
Actually it's funnier than that. It looks like a spam bot that uses the most popular words in forums to spam ads, this case it is "Mycleanyouknowwhat". Let's call it the Vitriol Spam Bot 1.0!
"If Natalie Portman is not measurable, hot grits are Fictitious." - My new signature !
It is a parody of a few people, but in particular one person, APK, who will argue near indefinitely with trolls using massive posts and links of lists to prove his "points." Some of the trolls may not have a life, but it is hard to beat the original, e.g. this story where over 200 of the 250 comments are him arguing with trolls, or possible with himself given many posts are within a few seconds of each other in a thread, sometimes involving sappy apologies from "those he's defeated."
This is why they say someone who eats a healthy diet "eats healthy" instead of "eats healthily".
"I like to eat Italian." => "I like to eat Italian food."
"I like to eat healthy." => "I like to eat healthy food."
So could you please clarify your claim that "to eat healthy" is not valid English?
when you have a bicycle frame made of it