Comments for Nanotech Marketplace

Comment on Helios propulsion system (using 0.1KT nukes as space propulsion system)? by Cloudff7yaoi

Cloudff7yaoi — Fri, 04 Jun 2010 15:36:16 +0000

Helium 3 fusion is the future of space travel. There are huge amounts buried in the moon. Its flowing over our magnetic shield right this moment. Small bursts over time could build up to about half the speed of light. Its actually what nasa s working on right now. Mouse dude if we had carbon nanotube technology that actually functioned as effectively as it could nuclear propulsion would be feasible. I realize they haven’t succesfully performed a fusion reaction that didn’t require more energy than it produced. I just think that fusion is more feasible.

Comment on Helios propulsion system (using 0.1KT nukes as space propulsion system)? by Andrew S

Andrew S — Fri, 04 Jun 2010 15:03:30 +0000

It is still not doable. Carbon fibre is completely unsuitable for this purpose. There is a mainstream perception that carbon fibre is some kind of engineering miracle and it is variously cited for being incredibly strong, rigid or whatever when in reality it has very specific properties that make is suitable for a certain class of problems and nothing else.

This kind of combustion chamber is not one of them. Carbon fibre has very poor shock/impact resistance which is what you need here. You can see this by watching a few motor races and seeing how easily carbon fibre shatters in relatively minor shunts.

Carbon nanotubes are the next “miracle material” that are perceived as the ultimate material for any challenging problem. However, that is even easier to dismiss because right now despite millions having been spent on research we have no way of manufacturing large components from them.

Comment on Helios propulsion system (using 0.1KT nukes as space propulsion system)? by eelfins

eelfins — Fri, 04 Jun 2010 14:06:33 +0000

As the article says, it was a precursor concept to the Orion project, which uses a pusher plate instead of a reaction chamber. They also found a way to increase the usefulness of the nuclear explosions by using shaped nuclear explosions that would direct more force against the plate. The designs were in fact very advanced, and most feel it could have actually been built. I think I can find where I read about it, it was an Amazon.com book preview, written by the son of the person who led the project.

Here it is, just click the book to read the first couple chapters:
http://www.amazon.com/Project-Orion-Story-Atomic-Spaceship/dp/0805059857

Comment on any help would be great an easy ten points? by Eric Arthur Blair

Eric Arthur Blair — Fri, 04 Jun 2010 13:30:46 +0000

http://images.google.com/

I’m going to pull up a couple leads on the toughest ones so you can see how it works.

Fullerene

http://images.google.com/images?hl=en&q=fullerene&gbv=2&aq=0&oq=fulleren

Nanotubes

http://images.google.com/images?hl=en&q=nanotubes+structure&gbv=2&aq=0&oq=nanotubes

Comment on some CNT questions…? by drutazo

drutazo — Fri, 04 Jun 2010 12:11:29 +0000

Ouch I don’t know the average yahoo answers will be able to help you much.

When you get access to your journals, look up his jacs one Effect of Acid Treatment on Carbon Nanotube-Based Flexible Transparent Conducting Films by Hong-Zhang Geng, Ki Kang Kim, Kang Pyo So,§ Young Sil Lee, Youngkyu Chang, and Young Hee Lee,

Sorry I don’t have the full ref as it was an advance article I downloaded back in may. But they report that after HNO3 and H2SO4 acid treatment there SWCN films have a increase in conductivity, and that there is a minor doping effect the acid used and that an acid wash helps remove the present of materials that are a hindrance to conductivity. I Guess it is down to the conditions of the acid wash, and a pay off of the removal of impurities that hindrance the conductivity vs add functional groups that could hindare conductivity.

Also there are several methods report out today about synthesis CNs, SWCN, MWCN and even double-barrow MW in which there is 2 SWCNs inside a larger SWCN, but I can’t reminder the jounrals refs.

Comment on Space Elevator,how to solve the problem of material strong enough to withstand its own weight? by Adam D

Adam D — Fri, 04 Jun 2010 11:38:26 +0000

How much helium? While helium is lighter than air, it can only create so much buoyancy in air, and that effect won’t help as much as the atmosphere thins. Think about how little a balloon can lift compared to its volume.

There are many carbon nanotubes designs that would work in theory but are not economically feasible. The whole idea of a space elevator doesn’t seem like a practical area of research at this point, we should be looking at alternative fuel that could be used to power space shuttles instead.

Comment on Space Elevator,how to solve the problem of material strong enough to withstand its own weight? by mrbungle3825

mrbungle3825 — Fri, 04 Jun 2010 11:23:51 +0000

The idea behind the space elevator is to get a weight at the end far enough from the surface that it creates tension on the cable, like swinging a ball on rope. I think what will have to happen is a high altitude helicopter will have to be made that can support the nano tube cable until this mass is attached to the end of it, and then it will support itself through centripetal force.

Comment on Space Elevator,how to solve the problem of material strong enough to withstand its own weight? by ?Mac?

?Mac? — Fri, 04 Jun 2010 11:18:27 +0000

Problem, the center of mass for the elevator has to be in the Clarke belt, some 22,000 miles. Even if the first 22 miles of the atmosphere were dense enough to create lift with your device that accounts for only .1 percent of the total length from ground to C.O.G. and does not factor in the counterweight.

Comment on Do CNT’s represent a potential environmental super-disaster? by yp_armando_uvalde

yp_armando_uvalde — Fri, 04 Jun 2010 10:30:42 +0000

No Philip, I do not know the answer. But I will do research. It is very important to me as it should be to others. There are so many unknowns and variables concerting this problem.
Thxs.

Comment on Do CNT’s represent a potential environmental super-disaster? by jorganos

jorganos — Fri, 04 Jun 2010 10:06:17 +0000

The same case can be made for any kind of nano-particle. From a purely chemical point of view, the carbon nanotubes are considered inert.

The is a similarity with asbestos – the material forms needles which are not broken down by organic processes. Asbestos causes the same problems as other silicates ground to dust, permanent damage of lung tissue when inhaled. Yes, short strands of carbon nanotubes could do that, too – it’s a mechanical rather than chemical process.

Like with asbestos, the most dangerous form is aerosol, not watery solution. If you drink water with a thimbleful of asbestos, the adverse effects are a lot smaller than when inhaling asbestos dust.

Combinatory effects with other substances cannot be tested. Carbon nanotubes have the potential to capture ions or small molecules inside, creating rather different chemical properties. There is no scientific way to prove that they are safe.

The expected threat to water ecology is several orders of magnitude lesser than that of standard waste water production, with heavy metals, drug metabolites, pesticides etc. invading.

The EPA should take immediate steps to reduce climate influencing gases, too. Has anyone managed to get this issue past the oil industry lobbyists in Washington (starting with the President)?