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Self-healing material can build itself from carbon in the air

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Re: Self-healing material can build itself from carbon in the air

#41

Post by shoo »

mcbits wrote: post #38
cialowicz wrote: post #10

Earlier quoted context omitted.

Skyscrapers are mostly empty space inside. The Great Pyramid of Giza weighs about 6 million tons, so we’d be producing about 7000 of them annually. Maybe we could just plop them all in the ocean? ;)

I'd probably mess up the arithmetic, but I wonder how many skyscrapers or Great Pyramids could be packed in a volume of 1 cubic mile. That's how much oil we use per year.[0] (All sources combined are equivalent to about 3 cubic miles of oil.) It would be nice to find a way to bump that up a couple orders of magnitude without actually pulling that much oil/equivalent out of the ground, since there literally isn't enou…

Start with a Great Pyramid of Giza, or locally sourced substitute following the traditional recipe [1]:

  * 5.5 million tonnes of limestone
  * 8,000 tonnes of granite
  * 500,000 tonnes of mortar
For a simple approximation, we ignore ingredients that are not limestone.

mass of limestone in great pyramid of giza

  = 5.5 * 1e8 kg of limestone
Volume of limestone in one great pyramid of giza, assuming medium-high density limestone at 2500 kg / m^3 [2]

  = 5.5 * 1e8 kg / (2500 kg / m^3)
  = 2.2 * 1e5 m^3
allegedly there are 4.168e+9 m^3 cubic metres per cubic mile. That gives about 19,000 great pyramids of giza per cubic mile.

[1] https://en.wikipedia.org/wiki/Great_Pyramid_of_Giza#Material... [2] http://www.natural-stone.com/limestone.html

edit: when i try to estimate by geometry from the pyramid dimensions, instead of by density, i end up with about 2,000 great pyramids of giza, but that's without trying to understand what the volume of a pyramid actually is, because i am not clever enough to do that.

Re: Self-healing material can build itself from carbon in the air

#42

Post by Scriptor »

agumonkey wrote: post #39
rosshemsley wrote: post #31

The cynic in me expects to click this and find an article about trees. https://www.youtube.com/watch?v=ifk6iuLQk28

The more I know about biology the less I enjoy (applied and commercial) science because .. well biology does much of it right now.

I bought some houseplants a bit back and it's been fascinating to see how quickly they grow. The vast majority of that new mass literally comes from thin air.

Re: Self-healing material can build itself from carbon in the air

#43

Post by pvaldes »

The ultimate war in misted battlefields (trumpet sound):

Fancy polymer made of delicious sugar!!!...

... against lichens and bacteria from the badass planet earth!!!.

Guess who of both will release chemicals, distroy their opponent and feed on their guts after being trained for millions of years in extreme survival (colonizing lava fields and sun scorched areas)?

Re: Self-healing material can build itself from carbon in the air

#45

Post by agumonkey »

Scriptor wrote: post #42
agumonkey wrote: post #39

Earlier quoted context omitted.

The more I know about biology the less I enjoy (applied and commercial) science because .. well biology does much of it right now.

I bought some houseplants a bit back and it's been fascinating to see how quickly they grow. The vast majority of that new mass literally comes from thin air.

Then think about the internals, the subtleties of cellular matrices. It's as beautiful as processor manufacturing, if not more, and right before your eyes all around.

I laugh yellow~ when people dream of robotics.. when I see an annoying mosquito, I look at how thin all this is and yet it lives, flies, perceive the world quite a bit ...

To an extent I think the future will just be the same old past except we'll now understand nature a bit more. I hope so.

Re: Self-healing material can build itself from carbon in the air

#46

Post by s_kilk »

agumonkey wrote: post #39
rosshemsley wrote: post #31

The cynic in me expects to click this and find an article about trees. https://www.youtube.com/watch?v=ifk6iuLQk28

The more I know about biology the less I enjoy (applied and commercial) science because .. well biology does much of it right now.

There's a certain fetish for technology that blinds us to the obvious power of biological systems. We end up chasing pipe dreams of self-assembling materials while ignoring the already-existing self-assembling materials right in front of us.

Re: Self-healing material can build itself from carbon in the air

#47

Post by PopeDotNinja »

agumonkey wrote: post #39
rosshemsley wrote: post #31

The cynic in me expects to click this and find an article about trees. https://www.youtube.com/watch?v=ifk6iuLQk28

The more I know about biology the less I enjoy (applied and commercial) science because .. well biology does much of it right now.

I remember listening to a AI researcher talk about how his quest to develop an advanced intelligence led him to realize he could do that by having a child.

Re: Self-healing material can build itself from carbon in the air

#48

Post by pvaldes »

gigatexal wrote: post #4

Could you “clean the air” by creating many such breaks and having it pull co2 out of the air?

Pass 1: culture a huge amount of spinachs that pull co2 out of the air

Pass 2: distroy this plants releasing co2 again in the air to obtain chloroplasts from the upper half of the creature. Set free again the co2 saved in roots. (Alternatively pick only leaves from the spinach).

Pass 3: use this chloroplasts to recover a part of the co2 released in the pass 2

Pass 4: ... D'oh!

Re: Self-healing material can build itself from carbon in the air

#49

Post by taf2 »

s_kilk wrote: post #46
agumonkey wrote: post #39

Earlier quoted context omitted.

The more I know about biology the less I enjoy (applied and commercial) science because .. well biology does much of it right now.

There's a certain fetish for technology that blinds us to the obvious power of biological systems. We end up chasing pipe dreams of self-assembling materials while ignoring the already-existing self-assembling materials right in front of us.

It’s called a god complex? But the pragmatic reasoning is that what we build we can control more so than what nature has evolved. If for example, I can build a robot to pick up my trash can and walk it down to the street once a week and it’ll self heal all the wear and tear that is pretty nice.
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