"...an approximately equal chance that Pat Buchanan will be nominated as the Democrat candidate..."
True, but there is also a non-zero probablity that (given enough time and energy) an LHC event may spontaneosly generate a democratic candidate worth voting for...
It seems like in this day and age it's far more of a "who you know" vs. a "what you know" world... (an opinion, I *could* be wrong...). I think a sci-fi story that really speaks to this notion and the absolute apparent unfairness of life is Niven's story, "A Gift From Earth." This is one I'd REALLY like to see put on film. It has the advantage of being from his popular "Known Space" series but stands alone rather nicely.
> the Bremsstrahlung losses absolutely kill you.
Gotta admit, I forgot about Bremsstrahlung... however I didn't think that inertial confinement relied on magnetic fields... just a big evacuated chamber... or does it? If there is no need for magnetic confinement then there ought not to be much in the way of Brem losses. But you're definatly right about the fact that it is harder to touch off a D-He3 reaction.
>Which you soak up with lithium, generating more tritium.
True enough, however, if you put a layer of Li thick enough to capture all of the neutrons, you'll fill the reactor vessel with lithium... (Ok I'm exaggerating) You won't be able to catch them all... the mean free path of neutrons in lithium might be pretty big, but I don't know what the cross section of lithium is. It probably isn't as big as Halfnium or other "conventional" neutron absorbers. You'll still have a brittle pile of hot steel to replace.... are you going to want to shut down a power plant for 20 odd years while the vessel cools to the point where it can be removed? I doubt our electricity producers would want that.
You use D-T because it is by far the easiest reaction to set off... and I sure as heck am not against using it but people should be aware of the downside...
The main problem with Deuterium-Tritium fusion, even IF you get to breakeven and beyond is that the energy released has a very substantial neutron component. Unlike gamma or beta radiation, neutrons stick to atomic nucleii and change the atoms of say, the reaction chamber walls into radioactive isotopes which in most cases, are actually far "hotter" than the low-level nuclear waste from fission power plants. Now, you say that you don't change the reactor vessel very often, but with most steel or other possible chamber materials, this bombardment of neutrons also makes the chamber very, very brittle. Now you are faced with the problem of changing and disposing of a very hot pile of material. Much better if you use Deuterium and Helium-3.
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How would the article explain the success of Steve Ballmer??? :-o
Captain's log, stardate 5431.4. For 15 hours and 20 minutes, we have been following the ion trail of the spaceship that has Spock's brain. ...
"...an approximately equal chance that Pat Buchanan will be nominated as the Democrat candidate..." True, but there is also a non-zero probablity that (given enough time and energy) an LHC event may spontaneosly generate a democratic candidate worth voting for...
My Firefox didn't open any popups but it alerted me that it blocked *7 popups* in total!
It seems like in this day and age it's far more of a "who you know" vs. a "what you know" world... (an opinion, I *could* be wrong...). I think a sci-fi story that really speaks to this notion and the absolute apparent unfairness of life is Niven's story, "A Gift From Earth." This is one I'd REALLY like to see put on film. It has the advantage of being from his popular "Known Space" series but stands alone rather nicely.
the high level of quality of many commercial software products...
> the Bremsstrahlung losses absolutely kill you. Gotta admit, I forgot about Bremsstrahlung... however I didn't think that inertial confinement relied on magnetic fields... just a big evacuated chamber... or does it? If there is no need for magnetic confinement then there ought not to be much in the way of Brem losses. But you're definatly right about the fact that it is harder to touch off a D-He3 reaction.
>Which you soak up with lithium, generating more tritium. True enough, however, if you put a layer of Li thick enough to capture all of the neutrons, you'll fill the reactor vessel with lithium... (Ok I'm exaggerating) You won't be able to catch them all... the mean free path of neutrons in lithium might be pretty big, but I don't know what the cross section of lithium is. It probably isn't as big as Halfnium or other "conventional" neutron absorbers. You'll still have a brittle pile of hot steel to replace.... are you going to want to shut down a power plant for 20 odd years while the vessel cools to the point where it can be removed? I doubt our electricity producers would want that. You use D-T because it is by far the easiest reaction to set off... and I sure as heck am not against using it but people should be aware of the downside...
The main problem with Deuterium-Tritium fusion, even IF you get to breakeven and beyond is that the energy released has a very substantial neutron component. Unlike gamma or beta radiation, neutrons stick to atomic nucleii and change the atoms of say, the reaction chamber walls into radioactive isotopes which in most cases, are actually far "hotter" than the low-level nuclear waste from fission power plants. Now, you say that you don't change the reactor vessel very often, but with most steel or other possible chamber materials, this bombardment of neutrons also makes the chamber very, very brittle. Now you are faced with the problem of changing and disposing of a very hot pile of material. Much better if you use Deuterium and Helium-3.