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Team Confirms UCLA Tabletop Fusion
An anonymous reader writes "A team of New York physicists has confirmed that a tabletop contraption made at UCLA does in fact generate nuclear fusion at room temperatures, using pairs of crystals and a small tank of deuterium. But unlike less reliable reports back in the 1980s, there's no talk this time of producing endless supplies of power. Rather, the technology could lead to ultra-portable x-ray machines and even a wearable device that could provide safe, continuous cancer treatment."
From TFA: I'm surprised that the article didn't go into more depth on the explosives detection angle, as a neutron generator is an excellent method for detecting fissionable material, and I'm sure the folks over at Homeland Security would like a better way to guard against nuclear devices being smuggled into our country.
For more info on neutron generators and their possible application in fissionable materials detection, please look here (PDF warning).
____
~ |rip/\/\aster /\/\onkey
Crystals and holy water?
...will be for mood rings that give you finger cancer.
It's quite an accomplishment. However, as the article noted, they don't mention even the remote future possibility of creating a self-sustaining reaction. So I'm assuming that there is no way even in principle this technology could be scaled to yield more power than it uses.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
"Our device uses two crystals instead of one, which doubles the acceleration potential," says Jeffrey Geuther
Yeah well, now I'm going to use three!
Although the device as a whole may be at room temperature, the region where the fusion reactions occur is at a much higher temperature (10^6K or similar) - as it is needed for fusion.
Speedy particles smashing into each other have a lot of kinetic energy in the center of mass inertial system. This is nothing different than 'heat'.
"application may come in the form of a battery-operated, portable neutron generator"
Wait, what? We finally got cold fusion, but 'batteries not included'?
Unpleasantries.
Also overlooked is the forthcoming businesses selling crystal pendants and key chains which "fight" cancer and provide other beneficial effects.
I will now take bids on licensing my screenname.
I hope this works out as a decent power source
Sorry to disappoint, but it's just not going to happen. These types of methods of fusion are always going to require more energy input than output. Efficient artificial reactors may be possible in the future, but for now they remain a pipe dream--especially 'cold fusion' ones.
Take off every sig. For great justice.
IANAP (I am not a physicist), but I do know that nuclear fusion doesn't create fallout like nuclear fission does. Perhaps this is what you are thinking of. I ought to also remind you that radiation plays a huge part in medical treatments of all sorts. So while you might have been sarcastic when you said 'tremendous idea,' I'd have to agree with you there.
Take off every sig. For great justice.
Its amazingly clear that not only have few of you RTFA, most have not even gotten past the title before you threw out a post.
Its a whole 4 sentences which make it clear that this is NOT a power source, and half the posts are talking about its potential as a power source.
Now if I could just find a way to bottle the power of human stupidity...
Darn, now I have to go sell my palladium stash that I have put away just in case someone actually made it work the old fashioned way.
"It's the height of ridiculousness to say for those 9 lines you get hundreds of millions."
Yeah beacuse everyone knows being continuously bombarded with X-Rays is safe.
But can it crank out 1.21 gigawatts?
Government's view of the economy: If it moves, tax it. If it keeps moving,regulate it. If it stops moving, subsidize it.
Now THAT would be a keychain toy worth buying.
Is it just me, or did this article make the Renselaar folks seem like smug jerks? As in, "Yes, not only did we prove that it works, but we proved that we can do it a lot better than those toking, surfing, hippies!"
The paper.
IANAP (I am not a physicist), but I do know that nuclear fusion doesn't create fallout like nuclear fission does.
Fallout is caused by one of two events:
1. Excess nuclear materials not consumed in the reaction are left behind.
2. The neutron radiation from the event interacted with nearby materials (such as the dirt on the ground) to create new radioactive materials.
Nuclear fusion is "clean" in that there are no radioactive materials left over from the reaction. However, it does produce an incredibly strong neutron flux which can easily create radioactive fallout in nearby materials.
http://en.wikipedia.org/wiki/Nuclear_fallout
Given how destructive neutron radiation is, I'm somewhat surprised that they'd be talking about strapping a reasonably strong source to someone's person.
Javascript + Nintendo DSi = DSiCade
The difficulty with small scale fusion isn't making it happen. That's been done many, many times. The difficulty with small scale fusion (and all fusion) is making it produce power (more power extracted from the reaction than put into the reaction).
That's where Pons and Fleishman got hosed. They claimed a 300% power surplus without experimental verification. This announcement is different from that for several reasons.
1) These guys are specifically not claiming excess power.
2) They're claiming to have lots of high-energy neutrons.
3) This is actually the announcement of a second group of scientists repeating the experiment and successfully verifying the results of the first group.
In short, this announcement is nothing like the cold fusion debacle of the late '80s.
Regards,
Ross
Ahem... or out of the country. Keeping tabs on one of the worlds largest nuclear stockpiles is a major, fulltime job and not one to be taken lightly.
Time flies like an arrow. Fruit flies like a banana.
Tabletop fusion has been in use for quite some time. This device looks like it's a little bit simpler than the Farnsworth fusor, but it's an incremental improvement, not a radical breakthrough.
The breakthrough would come should anybody ever figure out how to break even energetically in a tabletop fusion device, and I think it's quite possible that that will happen sooner or later.
mod parent down, the movie sucked
To Hell with the Queen of England!
What if the crystal cracked?
http://www.imdb.com/title/tt0083791/
Bury me in mashed potatoes.
I never let science get in the way of a snarky comment.
Proud member of the American Non Sequitur Society. We might not make much sense, but boy do we love pizza!
Indeed, it's different from all of those, read TFA. Here's a basic explanation of the device from RPI.
Tabletop fusion is hard. You have to be rolling 20's to get it started.
That is fusion. Moving neutrons from one atom to another increases the atomic weight of the recipient atom. You don't necessarily need to fuse atoms together to call something "fusion."
Given how destructive neutron radiation is, I'm somewhat surprised that they'd be talking about strapping a reasonably strong source to someone's person.
I think that's kind of the idea, if you were trying to kill a tumor with it.
At any rate, I get the feeling that the 'cancer treatment' idea was probably just something that whoever gave the interview to the article's author pulled out of their ass when they were asked about 'possible uses.' It sounds good, and who knows, it might even be true.
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
Erm, producing neutrons implies some sort of nuclear activity. Either fission or fusion of some sort of decay process (spontaneous neutron emission). By ruling out fission and neutron emission via decay, which are possible to do by knowing the inputs, you're pretty much stuck with fusion as an explanation for the output.
You make it sound like shuffling some neutrons around is easy. It's not. Producing a source of neutrons is a pretty nice feat by itself. However there's a very, very large difference between producing neutrons via fusion, and plonking down a SimCity 2000-esque, pollution-free, "Fusion Power Plant."
"Ladies and gentlemen, my killbot features Lotus Notes and a machine gun. It is the finest available."
And what are neutrons? Oh yeah, just one of the most penetrating and dangerous forms of radiation. Why else do you think that when they had to find a form of radiation that could kill tank crews inside their vehicles, the viable choice was the neutron bomb?
Pure fusion bombs create huge numbers of neutrons. If the explosion is near the ground, these neutrons can activate the debris that gets sucked into the mushroom cloud and create plenty of fallout. (Not to mention, most bombs use a natural uranium case to get a cheap energy boost when it's fissioned by the extra fusion neutrons. Most of total the energy output is often still fission.)
And any amount of emissions that's intense enough to kill cancer tumors isn't exactly "small".
Also: Nowhere in the article does it mention anything about breaking apart massive atoms and leaving behind radioactive isotopes that are chemically reactive in the human body; Which, I assume, is what you're so worried about.
Instead, you add neutrons to the the elements already inside your body, thereby turning them into dangerous radioactive isotopes where they sit.
> Are we talking x-ray laser sort of technology? Is 200,000 electron volts enough to do significant damage? Surface burns and radiation poisoning?
That's why we mount them on sharks' heads.
Sheesh, evil *and* a jerk. -- Jade
Another big difference is this team is announcing their results in a technical journal, not in a press conference.
It'll be interesting to see what comes of this.
http://lkml.org/lkml/2005/8/20/95
Bottle the power of human stupidity? Sorry, you are too late. Look no further than the Vatican, Al Qaeda, or any other religions institution. Superstition, fear of death, and the promise of eternal life are all their tools, and with proper respect of their un-verifiable claims (faith), lack of reason, and willingness to submit you too can be their servant.
~Religion is O.K., as long as it gets you laid.
"Now if I could just find a way to bottle the power of human stupidity..."
it's called 'Beer'
The Kruger Dunning explains most post on
Right you are.....
Although the figure is somewhat disputed by the US Customs, who claim they inspect a larger percentage of what they deem "high risk" containers, apparently about 2% of all containers entering the US are actually inspected (i.e. opened and the contents examined).
None of them can see the clouds; The polished wings don't care.
Dr Ray Stantz: You know, it just occurred to me that we really haven't had a successful test of this equipment.
Dr. Egon Spengler: I blame myself.
Dr. Peter Venkman: So do I.
Dr Ray Stantz: Well, no sense in worrying about it now.
Dr. Peter Venkman: Why worry? Each one of us is carrying an unlicensed nuclear accelerator on his back.
That's where Pons and Fleishman got hosed. They claimed a 300% power surplus without experimental verification.
I think the more important difference between this and Pons and Fleishman's cold fusion is that this is clearly fusion, and P&F wasn't. The effects P&F observed were probably the result of a chemical reaction and/or bad experimental design. They didn't observe any of the characteristic radiation or products.
FYI, this isn't the first tabletop deuterium fusion discovered. See bubble fusion.
If you can read this sig, you're too close.
I was a plasma physicist, and did some research on topics related to fusion before quiting to become a programmer.
Basically, you're right. The nice things about fusion (or some of them at least) are that there's no scope for a Chernobyl-style meltdown and the reaction products and reactants are safe.
The problem, as you say, is that it's an excellent source of neutrons. The generator and its housing have to be designed to absorb as much of that neutron flux as possible. This inevitably produces radioactive isotopes in these materials, which will eventually break down to the point that they must be replaced.
The nuclear waste associated with a fusion power plant isn't as bad as that for a fission one, but it still exists and still needs to be dealt with.
It's official. Most of you are morons.
What I'm wondering is whether this could be used to create a hybrid device that blast fissionable material with reaction initiating neutrons, rather than balance the fissionable material on the knife's edge of criticality. If so then fission reaction would stop immediately upon loss of initiating neutrons from the fusion source and you have a much safer nuclear reactor design. Could this also be used to burn our existing stockpiles of waste, and if not practical with these neutron sources, could future more efficient fusion reactors be used to extract additional energy from nuclear waste while consuming and disposing of it at the same time?
Letter To Iran
CLICK HERE for a portable fusion device that can help you Add Inches!!!
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I've never heard of deuterium fission. At the low end of the periodic table, it's far more energetically favorable for thing to fuse. I'm no expert, but D fission might even be endothermic.
You can think of their experiment like the classic Rutherford experiment, except they've got D+ ions being shot at a sheet of D. The two D+D fusion reactions happen with equal probability:
D + D -> T (1 MeV) + p (3 MeV)
D + D -> He3 (0.8 MeV) + n (2.5 MeV)
What they did in the experiment was to look for 2.5 MeV neutrons, because that reaction will _always_ produce a 2.5 MeV neutron. They also looked at associated X-rays. (If it was a fission neutron, it would probably be a different energy, and again, I can't find any reference to such a phenomenon.) Then they correlated their results to a computer simulation. I don't know why they didn't bother to look for the H and T. They may not have had the equipment, or they considered it outside the scope of the experiment's purpose as a neutron source.
The caveat to this experiment is that neutron and x-ray detection is something of an art, and must be done correctly; I'm not qualified to comment on their setup. This experiment makes sense according to normal physics, though.
I think you missed the point (but perhaps not). A bale of cocaine would be summarily removed to the evidence locker... probably in downtown *major metro area*. No one would go carving into the thing to check to see whether there was a nuke inside (they'd want to weigh it for the inevitable press release)... A simple remote detonation... bingo! You flatten at least one *major metro area* precinct. If it were a big enough 'bale' it may go into the federal building, too.
I'm actually quite clueless about what they do in cases of large seizures, but I don't think it matters. It (likely) goes somewhere inland, and the cops/agents wouldn't likely look for a 'second' offense when they find a bale of cocaine.
I guess the beauty of that plan is that if it gets through, you could pay for the costs of the nuke with the proceeds of selling a bale of coke to the plastic surgeons in said *major metro area* before you detonate the bomb...
FWIW, The OP's point (joke) is well-made and scientific sniping isn't really necessary, although your knowledge does add to the discussion... Perhaps it was a bit mis-placed, though? I'm not trying to be a dick, just giving a little constructive criticism...