Halving Half Lives 406
An anonymous reader writes "PhysicsWeb is reporting that German scientists may have found a way to significantly reduce the radioactive decay time of nuclear waste. This could render the waste harmless in just tens of years and make disposal much less difficult as opposed to current standards. From the article: 'Their proposed technique - which involves slashing the half-life of an alpha emitter by embedding it in a metal and cooling the metal to a few degrees kelvin - could therefore avoid the need to bury nuclear waste in deep repositories, a hugely expensive and politically difficult process. But other researchers are skeptical and believe that the technique contradicts well-established theory as well as experiment.'"
why bury it all? (Score:2, Insightful)
Um (Score:4, Insightful)
In order to get the radiation down to safe levels, you have to out-radiate everything up to that level. Same radiation, doesn't matter if it takes the normal amount of time or less.
Re:Um (Score:3, Insightful)
Re:Um (Score:2, Insightful)
Re:Um (Score:5, Insightful)
It is easy to shield high level waste. Water will work just fine. If you only have to store it for a few years then it really becomes a simple problem.
The sad thing is I doubt that this could work they way the say it will. It really needs to be tested.
I could understand if they used a good neutron emitter like beryllium. When an Alpha particle hits that you get neutrons. The neutrons could then cause an increase in decay type reactions, if it was captured by a nuclei of the the substance that you wanted to degrade. Even that is a big maybe since I am just thinking of ways it could work without doing any math.
Even then it seems like you wouldn't get anything like what this guy is claiming.
Comment removed (Score:3, Insightful)
Energy-balance? (Score:4, Insightful)
Re:Um (Score:4, Insightful)
You're right. But (as other posters have said) it is [probably] a good tradeoff. In my laboratory, we use ozone to purify water (read: kill bad things therein). It's nasty stuff, but it's so reactive (therefore lethal to buggies) that it disappears really fast. We used to use chlorine, which wasn't nearly so nasty, but which stuck around for much, much longer than the ozone. If you can deal with the reactivity during the worst of the reaction (at the very beginning), then you're pretty much home-free. Constant exposure to low-level chemicals (or radioactivity) which you might not know about is most likely much worse than very quick exposure to high levels of the same stuff which you DO know about.
Re:why bury it all? (Score:1, Insightful)
Even if this works, it will be tough. (Score:4, Insightful)
Joules in - Joules Out (Score:3, Insightful)
Nuclear energy is roughly as follows: Ore is mined -> ore is refined -> Energy is extracted from fuel -> Spent fuel is prepared and kept in a single degree kelvin fridge for several years. -> Safe spent fuel is disposed
How many Joules does it take to keep the spent fuel at that low temperature for so long as compared to the energy extracted? Is there an orders-of-magnitude difference?
Re:Kerning (Score:5, Insightful)
Easy: General education level, good science classes in high school, social image/reputation of science and scientists, and an absence of religious bias against science.
Niels Bohr was Danish, FWIW.
Re:Um (Score:2, Insightful)
There is no panacea and I doubt this is one. Any material to shield radioactivity will also become radioactive. Heck, even fusion isn't completely clean, I think one of the project goals of ITER is to find ways to manage the radioactivity of the components for when it is dismantled.
Alpha radiation (Score:1, Insightful)
I'd be more impressed if they found a way to dispose of gamma emiters safely
Re:why bury it all? (Score:3, Insightful)
On the other hand, I think throwing the stuff away is foolish. We need to store it in case we come up with a way to reuse it.
d00d! (Score:5, Insightful)
FYI, radioactive decay isn't caused by thermal energy. Notice the lack of a term for temperature in the relevant equations [wikipedia.org].
> how does some of what passes for scientific papers get accepted, anyway? box tops? there's a lot of stuff that the mass media picks up on and publicizes that just can't stand the smell test.
One might ask a similar question about Slashdot moderation.
Re:Um (Score:5, Insightful)
I just think it's a shame the Integral Fast Reactor project got canned back in Clinton's day. If it hadn't been shut down, maybe nuclear waste wouldn't be nearly as huge a problem now...
Re:why bury it all? (Score:1, Insightful)
Nice troll, but I'll feed you anyway.
You see apart from the sun there's this big gravity well in the centre of the solar system - oh, wait, it IS the sun! So as long as it makes earth orbit (ie we can get it outside _Earth_'s gravity well), and it gets fired directly towards the sun (think slow burn or compressed gases or similar), I doubt it can miss, even if it takes a few years to get there. We know how to do the calculations to handle planetary interference.
And let's face it, we don't care if we miss the Sun and hit Mercury anyway.
Oh, and if you think we can't fire it hard enough to leave orbit, there are some NASA engineers who got Voyager 1 [wikipedia.org], Voyager 2 [wikipedia.org] and their relatives up who'd like to talk to you.
Re:Um (Score:4, Insightful)
another alternative? (Score:2, Insightful)
much harder than you think (Score:3, Insightful)
To really get rid of it by dropping it in the sun will require you to cancel out its orbital velocity relative to the sun, 66,000mph! You could reduce that somewhat by complicated slingshot trajectories but then if you don't get it quite right it could come right back at you. Of course dropping it into Jupiter's atmosphere (or Venus for that matter) would probably be sufficient.
Just do it the easy way and put it on the moon! (www.space1999.net).
Re:why bury it all? (Score:3, Insightful)
Aside from the risks and costs of such a venture, here's an even more important question? How do we know that dumping material into the sun might not somehow affect the sun in some way?
Granted, it seems crazy to imagine it might, but who knows? I don't know if we have a lot of experimental data on the subject. If dumping heavy radioactive elements into the sun *did* have some long-term effect, it seems we'd be about as screwed as we could possibly be.
We might try to pray to Thor to save us, but sometimes I think he's just repeating recorded messages back to us as it is.
Too Expensive to Measure (Score:4, Insightful)
But there's scientific hope for better engineering that could change that. The extra energy more quickly removed from the spent fuel in this process could possibly be harnessed. That would mean that nuclear fuel not only is made safe in manageable durations, like less than a century, but more of its potential energy is available right away, or during the lifetime of its "soft landing". The combination of greater efficiency and closed-ended management does transform at least that part of nuclear's currently unacceptable cost basis.
As long as we're redesigning these reactions, we should do it all in space. There's plenty of microtemperatures out there; microgravity can make operations more energy efficient; security is less fuzzy; accidents have less exposure to vulnerable facilities, ecosystems and organisisms. It's still risky and expensive transporting fuel out of Earth's gravity well, but that's a lot more addressable by failsafe engineering than terrestrial proliferation.
Re:There's way too much waste (Score:1, Insightful)
But we do have the resources to process it into a chemically stable and fairly strong ceramic, encase it in steel, further encase it in concrete, and bury it 1500 feet underground in a guarded mine shaft where it will be safe for 10000+ years. For a definition of safe, see the above post by another reader about the test he witnessed where they launched an inert cask through a concrete wall on a rocket sled.
Unfortunately, quite a few people who generally don't even know the difference between a gamma ray and an alpha particle have declared themselves sufficiently knowledgable to declare that such a solution is not safe, and spend much the energy they have left over from preaching about the horrors of fossil fuels to decry the very thought of a federal nuclear waste repository.
Re:why bury it all? (Score:4, Insightful)
Keep in mind that you aren't going to load up a rocket to full capacity with nuclear waste. You need to contain it somehow, preferably in multiple boxes that will protect it in case of an accident on launch (or at least until it escapes Earth's gravity and the Sun's gravity takes over). Even then you're better off not loading it to capacity anyway, to make very sure you have enough lift and fuel to achieve its mission.
Also keep in mind that as far as I know all of our launch vehicles are designed to carry payloads into orbit, not all the way to the sun. Yes, we launch stuff to Mars and other planets, but not to the Sun. We would have to design and test a launch vehicle (even if just a second stage vehicle that would go from orbit to the Sun) specifically for the task at hand.
Finally, we have a large backlog of waste material that needs to go as well. This means more rockets to get the job done, which means more money. This also assumes we can't recycle some of the waste, which is a very real possibility.
Re:Kerning QWZX (Score:1, Insightful)
"German" is not a race, no matter how nazi your brain.
Sheesh. I know the ignorance of Slashdot knows no bounds, but do a little research [wikipedia.org] before spouting off.
The whole notion of distinct "races" is contrived. Even skin colors aren't that neat, which is what we usually reduce "race" to. Our species family tree is very interwoven, and overall differences are superficial.
What we call "race" is really geographic origin. Yes, there have been some amount of mixing, but not enough (yet) to do away with the genetic difference between people. I mean, obviously, otherwise we'd all be the same shade of light brown. It's pretty obvious you haven't travelled much, otherwise you'd see distinct physical difference between peoples of different areas.
How do you think these differences came about? Why do you think dark skinned people tend to live in bright areas? Why do you think Asian noses have evolved to be small and close to the face? (hint: protection). Why do you think the sickle-cell anemia gene is so prevalent among Africans? (hint: malaria protection). Surprise! Evolution works on isolated human tribes, just like it works in isolated animal groups. Imagine that.
And it's pretty damn amazing how people who lived in African savannas are pretty damn good at running and athletics. Oh, sorry, but that's racist. But Asian noses are not.
And then it's considered racist that maybe, JUST MAYBE, brains might be subject to the same evolutionary pressures. How foolish and arrogant we are to think that we're not subject to nature's laws that we find politically inconvenient.
Re:Kerning QWZX (Score:2, Insightful)
So the rest of your nazi gibberish isn't worth reading, as you pretend to be expert in "race", when all you are is a garden variety racist.
There's nothing "maybe" about your racism. Classing broad related groups of people as races, then ascribing innate behavioral traits to them, is by definition racist, regardless of the "considerations" that wound your denial complex.
What's sad about people like you is that you can't even blame your parents for your stupidity. It's all your own fault, regardless of which continent your ancestors live for the last couple-few thousand years. Even sadder is that evolution has allowed your traits to survive, either out of genetic irrelevance or some kind of species need for self-destruction that we've long ago outgrown.
Anonymous nazi Coward.
Re:why bury it all? (Score:3, Insightful)
Only a person who:
A) Has no idea how heavy uranium is
B) Has no idea how much fuel it takes to put even a pound into orbit
C) Doesn't understand sheer idiocy of strapping a large amount of radioactive matter to a gaint fuel tank
would suggest such an idea.
(It's not that I'm calling the poster stupid. Just his idea. It's like a man who knows nothing about electricity asking why you can't stick a fork in a wall outlet.)
The idea is deeply flawed on many levels.
Re:why bury it all? (Score:1, Insightful)
Re:Kerning QWZX (Score:3, Insightful)
"Eugenics" isn't a theory. It can't be "disproven". It's a political pseudoscience.
Affirmative Action is indeed racism, as its own name implies. It doesn't pretend to ignore race. Instead it engages the racist preferences and denials in their own terms. By looking at the results of recruiting practices, rather than the gamed mechanics.
I see racism all the time. And it's easy to see your yearning for "legitimate racism" in your comment. Those KKK "vocal extremists" numbered in the many thousands when they wore robes. When they burned houses and bombed churches, murdered children. Now that they don't wear the robes, they've got even more power without their repellent image. Your downplaying them, your naive attempt to shock by calling Affirmative Action "racist", all show you're new to the game of coy racism. Give it up now. Before you cheat yourself of the equal opportunity to know, work and play with people without regard to the persistent fictions perpetuated as "racism". You're young enough to quit. And old enough to know better. Give yourself the chance to live life with just humans, rather than letting the racists who set you up steal away the people who make life worth living.
Re:man, that old lie (Score:3, Insightful)
Woah, slow down... competition for silicon??? While it is true that silicon prices are high, it has nothing to do with the computer industry - in fact, silicon prices have dropped tremendously due to the massive scale with which it is produced. If not for consumer electronics, they probably never would have built these multi-billion dollar fabs that produce these new gigantic wafers. You'd still be using the little tiny wafers that they used in the 60's, and solar technology would still be priced out of everyone's range except for NASA. Not only this, but photovoltaic cells can be made with lower-grade silicon than microprocessors need, so they often use cast-offs from the semiconductor industry... further reducing the cost of solar energy.
Silicon is the 2nd most common element on earth - there is zero competition for the element, so what you are talking about is competition for the grown wafer, which is very complicated and expensive. Solar energy is starting to become cost-effective, but it's not like there is some vast conspiracy keeping it from taking off. One of the big problems is distribution of power - if it is cloudy in New York, but New York needs solar electricity, then you need to pipe it in from somewhere sunny. The problem is, the sunny place might be far away, and will almost certainly change all the time. The distribution grid would have to:
Wind energy actually has a similar problem - what if it's not windy where you need the power?
Someday, by piggybacking on cost efficiencies (or perhaps by developing totally new technologies), it will be easy to convince a homeowner to put some solar cells on their roof, especially in warm sunny areas where air conditioning is common. Right now, it is hard to tell someone that they need to spend 10 years worth of electricity bills on a solar panel installation. This is a practical matter, and has nothing to do with people buying graphics cards.
Re:Um (Score:3, Insightful)
I'm not completely sure what you mean, but if you want to extract the radiation energy from the cooled atoms it's impossible. Alpha particles will give off all their kinetic energy within micrometers and there's no way to stop it from heating the alloy. (Which you want to keep cold or the effect will stop).
If it had been neutrons it might have worked - they can often penetrate several meters through the right substances, and it should be possible to set up neutron-stopping elements inside some system where the heat could run a turbine.
Re:Um (Score:3, Insightful)
Problem from Maxwell's Equations (Score:3, Insightful)
Furthermore, charges aren't polarized-- fields are. Aren't you trying to set up some kind of polarized electric (or magnetic-- you say a material is polarizable, which seems to indicate magnetism) field?