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Halving Half Lives
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.'"
What's wrong with just launching it into the sun?
/* oops I accidentally made a comment, sorry */
Is this wise? Decreasing the half-life means increasing the radioactivity. Given the option of living near a nuclear waste site and living near the lab where this is performed, I'd choose the former....
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.
I'm so glad I'll be able to life in Prypiat in only 3280 years...
"A door is what a dog is perpetually on the wrong side of" - Ogden Nash
How do these Germans know so much about the atomic nucleus? Did Neils Bohr leave them a working model or something? The German contribution to nuclear physics seems really disproprtionate to their actual population. Is there something unusually German about the model they committed us all to when they kicked off the science in the 1800s?
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"How do you power your cooling process?"
"With that nulcear power plant in the next town over."
A feeling of having made the same mistake before: Deja Foobar
Ok, so all you have to do is cool it to near absolute zero. How long do you have to do that for and how much energy does it take to maintain it?
-matthew
"THERE IS NO JUSTICE, THERE IS ONLY ME." -Death
When you double the halve life the radiation is halve.
And also, first we need to build a fusion reactor to have energy to cool that shit.
If you mod this up, your slashdot background will turn into a beautiful sunset!
I haven't read the article, but doesn't cooling things to a few K consume a sizeable amount of energy?
Windows 2000 - from the guys who brought us edlin
There are lots of different kinds of nuclear waste - the worst excesses are things like uranium mines and the US's Hanford Washington and Rocky Flats compounds, plus wherever the Russian and Chinese nuclear weapons development work was done, with huge volumes of fairly high-level waste and even huger volumes of low-level waste. Leave aside the risks of rocket failure, we simply don't have the payload capacity to haul significant quantities of it into Earth orbit, much less out of the gravity well to take it on a sundive.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Insulators block electricity, not radiation. An insulator might help keep in beta-particles as they're just electrons, but not alpha. Remember, an alpha-particle is just a helium nucleus and (if memory serves) can be stopped by tissue paper. Gammas, of course, are the real nasty ones and need lead or something similar.
Good, inexpensive web hosting
How much power is going to be needed to cool the material to 4K? I imagine you'd be creating quite a bit of waste (some of which would be nuclear) by doing this, thus negating some of its usefulness.
Even if this works, it will be tough to use. You'll have to cool something that emits heat down to near absolute zero. The energy required for that refrigeration job will be greater than the heat energy the radioactive material will emit over its remaining decay life.
It all makes sense now, this is why we are only getting episodes!
*runs*
I wonder what this process would do to the thermodynamic equation for the entire lifecycle of nuclear energy. I am not teh Smrt, so bear with me
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?
Somewhere, something incredible is waiting to be known. -- Carl Sagan
Why is this modded informative? Has the poster or the moderator actually done this experiment? Have they even Read the Fine Article?
Counterintuitive, maybe. But then so is most of Quantum ElectroDynamics.
"It doesn't cost enough, and it makes too much sense."
We can achieve the same goal by allowing the reprocessing of nuclear "waste". PBS had a good interview on the subject, which mentions that power generating reactors are only permitted to extract less than 1 percent of the energy. This is what leaves the "waste" highly radioactive.
I keep putting the word waste in quotes, because it's more like a nuclear fuel reserve than an unusable energy source. Use all the energy, and the half-life of what's left is a few decades.
Can You Say Linux? I Knew That You Could.
I just read an article in from a few months ago in Scientific American about fast reactors that can use the "spent" fuel from thermal reactors. Their waste is 95% smaller than thermal reactors and dangerous for only 10s of years, not 10s of thousands of years. _That_ technology has proven in prototype reactors.
Prove this process and in less than a year the anti-evolutionists will be using it to discredit carbon dating.
> you slow down an atom to near absolute zero, you would be lengthening the half-life, say from 200,000 years to 400,000 or whatever, because the binding energy would stay the same, just the ability of the particles to break free would be reduced because of the slowed movements between the particles. you might even generate a spike in atomic activity when it warms up.
FYI, radioactive decay isn't caused by thermal energy. Notice the lack of a term for temperature in the relevant equations.
> 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.
Sheesh, evil *and* a jerk. -- Jade
Well, it's currently illegal to dump waste at sea due to the London Convention, so don't expect this solution any time soon.
Also, subduction zones aren't particularly stable and predictable, so the waste would likely spew about rather than being neatly sucked away. There was an article on New Scientist about this.
let's see..
nuclear scientists say this works and can happen, and have done experiments.
but Slashdot user swchrad (312009) disagrees! Well shit, guess we can abandon that idea then.
I love the "informative" mod, btw. Nice touch.
Quidquid latine dictum sit, altum sonatur.
Unfortunately it is much worse than just getting it into LEO or even Geo sync. First you need to put it on an escape trajectory to get it out of earth's gravity well. The problem then is it's floating around in a near Earth orbit (like those pesky asteroids we keep worrying about). After a few years/decades/millenia it could find its way back down.
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).
This development is encouraging, though of course not immediately useful. Because storing radioactive masses in even more metallic mass down near 0K for a century or more sounds like it consumes a vast amount of energy. Maybe more energy than the fuel produces while it's useful in reactors. Add the cost of building, securing and maintaining the nuke plant and its "detox" coolers, and nuke power still looks like a loser.
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.
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make install -not war
it might be, except that isn't true about the solar cells.
http://www.nrel.gov/ncpv/energy_payback.html
That is an older reference, some newer techniques are even more efficient, and there's at least one solar "breeder' facility out there that uses solar PV to manufacture solar PV. One of the more unfortunate aspects of solar cell production is competition for silicon. Our society is choosing "spend it now, who gives a fuck about our future, our kids and grandkids can go screw themselves" frivolity like throw away obsolete graphics cards good for 6 months and throw away ipods obsolete every year and throw away cell phones obsolete every other month it appears and so on. Why, you just *must* upgrade to the next 5% better CPU and mother board combo because "work" demands it, or a videogame addiction, etc., and etc. If we had a slightly saner set of priorities solar PV would be a lot cheaper right (cheaper as in money and cheaper as in resources needed) now with the tech already developed.
But, slashdot group think is, it is much better to make billionaires into trillionaires, so by all means dis solar, support the corrupt (highly corrupt) overly expensive nuclear industry (despite solar being practical fusion power and actually more high tech than fission power and certainly deserving of MORE R and D than dirty fission power) never get any at all because "it's not cost effective yet", keep spreading that lie (that's been a lie for over 25 years now)that it costs more in energy than it ever will put out, and just complain about things while you improve your scores in the latest first person shooter.
Note that beta electron emitters actually get a longer half-life out of this process, not a shorter one. It only shortens the half-life of alpha emitters and beta positron emitters. On the plus side, the main hazardous electron beta emitter that we care about is Tritium, which already has a very short half-life.
In fact, the effect on beta electron emitters could turn out to be even more useful. Using this effect to dispose of alpha emitters is a problem because the decay process emits heat, but you could use the same phenomenon to preserve your 12-year-half-life tritium, since you're suppressing the process that would be heating it up.
There's no failure quite as dissatisfying as a complete and total solution to the wrong problem.
You do not have to use lead for all gamma. Just the high energy. IIRC, similar material is used on the genesis module to lower the amount of radiation that will be affecting it.
I prefer the "u" in honour as it seems to be missing these days.
- fission
- alpha emission
- electron emission
- positron emission
- electron capture
(I don't include gamma emission, because, although it does occur frequently in the aftermath of one of the types of decay above, it generally has a very short half-life, so it typically doesn't affect the time it takes for an entire decay chain to go.) Processes 1-4 are all purely nuclear, and don't depend in any way on the surrounding electrons. Process 5 does depend on the surrounding electrons, and, e.g., can't occur in an atom that's been completely ionized down to the bare nucleus. However, when it does occur, the electron that gets captured, with extremely high probability, is one of the ones in the innermost electron shells (known as the K shell in nuclear physics). That's because the K-shell electrons are the ones whose wavefunctions overlap the nucleus the most strongly. If you embed the atom in metal, or cool the substance it's embedded in, it has very, very little effect on the K-shell electrons. The electrons in the surrounding substance aren't going to get into the act, either, basically because of the Pauli exclusion principle.Find free books.
This would ultimately have the effect of focusing more and more electric charge into a smaller area -- sort of analogous to the principle behind hydraulic brakes.
I don't think anybody's ever thought of radially polarizing a molecule before (probably because before fullerenes, no molecule had an inside and outside) -- hmm, could I get a patent on that idea?
Anyway, with all that unprecedented free electron charge at the interior of the nanotube, then perhaps it could more strongly accelerate that electroweak decay (IF their research is correct)
The sickle-cell genetics that allow a single gene, expressing a single protein, lacking in collapsed red blood cells, are far from the complexity in behavior. Certainly the complexity of behavior claimed by racists. This example is the kind of talk-the-talk, can't walk-the-walk argument from genetic ignorance that racists favor. Because so many people have learned only the buzzwords that they can't see through the BS.
"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.
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make install -not war
The solution to the radioactive waste problem already exists: breeder reactors. The reason they aren't being used is politics, not technology.
Even if we could dispose of the current high-level radioactive waste using this technique, it would still be irresponsible. Non-breeder reactors use only a tiny fraction of the energy stored in the nuclear fuel and throw away the rest, and that's an unacceptable waste.
alpha particles are not harmless, they just don't travel very far. You probably remember being told in highschool physics that a tissue paper could stop them, but you need lots of lead to stop gamma rays. What's important is how much energy they have, and what stopped the energy - the piece of tissue paper or lead atoms or your skin cells, and what byproducts there might be.
The three posts above yours talk about breeder reactors. That is, reactors that can can turn some isotopes into useful fuel as they create energy.
Your post talks about prefab reactors, like the French have been using for years and are improved further (it seems) with pebble-bed designs. These are not breeder reactors.
Also, the US has used breeder reactors. Fermi 1 even operated for a short time as a commercial breeder reactor.
Why do you turn one thing into another?
Toshiba's design uses liquid sodium as a coolant. These designs have been problematic in the past, for example Fermi 1 or Soviet nuclear subs.
I do agree with you that nuclear power is very misunderstood.
http://lkml.org/lkml/2005/8/20/95
The biggest political problem is the possibility of weaponization. From http://en.wikipedia.org/wiki/Breeder_reactor
"Use of a breeder reactor assumes nuclear reprocessing of the breeder blanket at least, without which the concept is meaningless. In practice, all proposed breeder reactor programs involve reprocessing of the fuel elements as well. This is important due to nuclear weapons proliferation concerns, as any nation conducting reprocessing using the traditional aqueous-based PUREX family of reprocessing techniques could potentially divert plutonium towards weapons building. In practice, commercial plutonium from reactors with significant burnup would require sophisticated weapon designs, but the possibility must be considered. To address this concern, modified aqueous reprocessing systems are proposed which add extra reagents which force minor actinide "impurities" such as curium and neptunium to commingle with the plutonium. Such impurities matter little in a fast spectrum reactor, but make weaponizing the plutonium extraordinarily difficult, such that even very sophisticated weapon designs are likely to fail to fire properly. Such systems as the TRUEX and SANEX are meant to address this. [8]"
-- Too lazy to get a lower UID.
Hrm. But since Gauss' Law says that there can be no electric field on the inside of a conductor, whatever is on or in the inside layers won't feel any affect from a charge placed on an outside shell. Since there's no net charge on the inside layers, there's no field either.
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?