High ozone probably would be extremely hazardous. I remember from organic chemistry that O3 cleaves double bounds into carbonyl groups. This would be great and all to kill insects: alkenes are vital to biological systems and cleaving them would obviously wreck havoc. Unfortunately, this cleaving is unselective. If the O3 would be absorbed into our body, it would attack our double bonds as well.
Actually, that reminds me a story an old chemistry professor told me about a doctor who was practicing a new method to cure cancer. The doctor would pump O3 into the patient and then feed them a reduction catalyst (such as platinum) and claim that it would kill cancer cells. What my chem prof was quick to point out (he was consulted by insurance companies in regards to this doctor) was that double bonds are Everywhere in our body, and while it probably would cleave the ones located in carcinogenic cells, it would also take out any others it could find.
In short, while O3 in the upper atmosphere is quite lovable, I anticipate that large concentrations on the ground (that would result from using it as a pesticide) would be quite toxic.
The above post makes an excellent point, there is currently no material that can sustain the enormous stress that would be required to construct a space elevator.
While there is no current material that yields the necessary strength/mass required in order to built a space elevator, realistic possibilities are on the horizon. Quite simply, with the advent of nanotechnology, we are nearing the technological feasibility of creating a material composed of intertwined nanotubes. This is theoretically the strongest material that can ever be created. Carbon-Carbon bonds are extremely strong and would be extremely densely packed in a nanotube pole. It would be an order of magnitude stronger than steel, as well as significantly lighter.
While nanotubes can already be readily produced (Dr. Smalley of buckyball fame operates a production facility), strong nanotubes rods have yet to be produced. This is due to a variety of technical hurdles that must still be overcome. Perhaps the foremost obstacle is getting the produced nanotubes to lie parallel to each other. The current production method has the nanotubes forming from a catalyst and then becoming intertwined in a jumbled mess. When tension is applies to the mesh, the rope breaks not within the nanotubes (which would require a great deal of energy), but between the nanotubes, unraveling them from each other. Attempts to get the nanotubes to align properly have failed. Nanotubes are not an easy molecule to work with. They have extremely strong cohesion forces and are very difficult to pull apart from one another. The obvious approach of functionalizing each nanotube in order to orient it correctly doesn't work as doing so causes the nanotube to lose much of its mechanical and electrical promising properties.
In addition, when nanotubes are put under extreme mechanical stress, the bonds within the nanotube shift. For example, I've seen simulations where the bonds separating two polygons disappears, creating what appears to be a bonding who in the nanotube. The hole then resonates through the nanotube causing significant weakening in the structure.
At a talk I attended, the most promising idea I heard discussed was a steel/nanotube alloy. The nanotubes would run vertically through the steel, reinforcing the structure in the same way steel rods are often used to reinforce concrete. This would alleviate the risk of the nanotubes becoming unraveled intermolecular while at the same time using their large intermolecular strength to reinforce the structure.
Of course, without any physical models, this is mere speculation. However, it suffices to say that a there are real possibilities of breakthroughs that would allow for the construction of such a space elevator.
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High ozone probably would be extremely hazardous. I remember from organic chemistry that O3 cleaves double bounds into carbonyl groups. This would be great and all to kill insects: alkenes are vital to biological systems and cleaving them would obviously wreck havoc. Unfortunately, this cleaving is unselective. If the O3 would be absorbed into our body, it would attack our double bonds as well.
Actually, that reminds me a story an old chemistry professor told me about a doctor who was practicing a new method to cure cancer. The doctor would pump O3 into the patient and then feed them a reduction catalyst (such as platinum) and claim that it would kill cancer cells. What my chem prof was quick to point out (he was consulted by insurance companies in regards to this doctor) was that double bonds are Everywhere in our body, and while it probably would cleave the ones located in carcinogenic cells, it would also take out any others it could find.
In short, while O3 in the upper atmosphere is quite lovable, I anticipate that large concentrations on the ground (that would result from using it as a pesticide) would be quite toxic.
The above post makes an excellent point, there is currently no material that can sustain the enormous stress that would be required to construct a space elevator.
While there is no current material that yields the necessary strength/mass required in order to built a space elevator, realistic possibilities are on the horizon. Quite simply, with the advent of nanotechnology, we are nearing the technological feasibility of creating a material composed of intertwined nanotubes. This is theoretically the strongest material that can ever be created. Carbon-Carbon bonds are extremely strong and would be extremely densely packed in a nanotube pole. It would be an order of magnitude stronger than steel, as well as significantly lighter.
While nanotubes can already be readily produced (Dr. Smalley of buckyball fame operates a production facility), strong nanotubes rods have yet to be produced. This is due to a variety of technical hurdles that must still be overcome. Perhaps the foremost obstacle is getting the produced nanotubes to lie parallel to each other. The current production method has the nanotubes forming from a catalyst and then becoming intertwined in a jumbled mess. When tension is applies to the mesh, the rope breaks not within the nanotubes (which would require a great deal of energy), but between the nanotubes, unraveling them from each other. Attempts to get the nanotubes to align properly have failed. Nanotubes are not an easy molecule to work with. They have extremely strong cohesion forces and are very difficult to pull apart from one another. The obvious approach of functionalizing each nanotube in order to orient it correctly doesn't work as doing so causes the nanotube to lose much of its mechanical and electrical promising properties.
In addition, when nanotubes are put under extreme mechanical stress, the bonds within the nanotube shift. For example, I've seen simulations where the bonds separating two polygons disappears, creating what appears to be a bonding who in the nanotube. The hole then resonates through the nanotube causing significant weakening in the structure.
At a talk I attended, the most promising idea I heard discussed was a steel/nanotube alloy. The nanotubes would run vertically through the steel, reinforcing the structure in the same way steel rods are often used to reinforce concrete. This would alleviate the risk of the nanotubes becoming unraveled intermolecular while at the same time using their large intermolecular strength to reinforce the structure.
Of course, without any physical models, this is mere speculation. However, it suffices to say that a there are real possibilities of breakthroughs that would allow for the construction of such a space elevator.