Slashdot Mirror
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 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
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.
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
How do these Germans know so much about the atomic nucleus? Did Neils Bohr leave them a working model or something?
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.
thegodmovie.com - watch it
Correct me if I'm wrong and it's been a while since I did high school physics but isn't alpha radiation pretty harmless?
I'd be more impressed if they found a way to dispose of gamma emiters safely
> 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
If you're going to dump the stuff, why not just dump it into one of the readily available (and very deep) trenches that feed various tectonic subduction zones? The earth literally will swallow it up in a short (in geological terms) period of time. That seems a bit safer than blasting it off into space or trying to make it orders of magnitude more radioactive in the short run to "bleed the nasties out."
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.
--
make install -not war
Funny that question doesn't get addressed. Getting even small amounts of matter within a few degrees of absolute zero takes a lot of energy. I'd be willing to bet the answer is no.
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.
"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 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.
You're a nazi clown. The Wikipedia entry you're citing for the nonsense that "German" is a race has only an "external link" to "race (historical definitions)" at the very end of the article. In other words, you're so demented in your committment to one of the 20th Century's worst bad ideas that you see documentation that you're wrong as proof that you're right.
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.
--
make install -not war
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.
--
make install -not war
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.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
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?