Posted on 04/27/2005 12:18:08 PM PDT by AntiGuv
LOS ANGELES - A tabletop experiment created nuclear fusion — long seen as a possible clean energy solution — under lab conditions, scientists reported.
But the amount of energy produced was too little to be seen as a breakthrough in solving the world's energy needs
For years, scientists have sought to harness controllable nuclear fusion, the same power that lights the sun and stars. This latest experiment relied on a tiny crystal to generate a strong electric field. While falling short as a way to produce energy, the method could have potential uses in the oil-drilling industry and homeland security, said Seth Putterman, one of the physicists who did the experiment at the University of California, Los Angeles.
The experiment's results appear in Thursday's issue of the journal Nature.
Previous claims of tabletop fusion have been met with skepticism and even derision by physicists. In 1989, Dr. B. Stanley Pons of the University of Utah and Martin Fleischmann of Southampton University in England shocked the world when they announced that they had achieved so-called cold fusion at room temperature. Their work was discredited after repeated attempts to reproduce it failed.
Fusion experts noted that the UCLA experiment was credible because, unlike the 1989 work, it didn't violate basic principles of physics.
"This doesn't have any controversy in it because they're using a tried and true method," said David Ruzic, professor of nuclear and plasma engineering at the University of Illinois at Urbana-Champaign. "There's no mystery in terms of the physics."
Fusion power has been touted as the ultimate energy source and a cleaner alternative to fossil fuels like coal and oil. Fossil fuels are expected to run short in about 50 years.
In fusion, light atoms are joined in a high-temperature process that frees large amounts of energy.
It is considered environment-friendly because it produces virtually no air pollution and does not pose the safety and long-term radioactive waste concerns associated with modern nuclear power plants, where heavy uranium atoms are split to create energy in a process known as fission.
In the UCLA experiment, scientists placed a tiny crystal that can generate a strong electric field into a vacuum chamber filled with deuterium gas, a form of hydrogen capable of fusion. Then the researchers activated the crystal by heating it.
The resulting electric field created a beam of charged deuterium atoms that struck a nearby target, which was embedded with yet more deuterium. When some of the deuterium atoms in the beam collided with their counterparts in the target, they fused.
The reaction gave off an isotope of helium along with subatomic particles known as neutrons, a characteristic of fusion. The experiment did not, however, produce more energy than the amount put in — an achievement that would be a huge breakthrough.
UCLA's Putterman said future experiments will focus on refining the technique for potential commercial uses, including designing portable neutron generators that could be used for oil well drilling or scanning luggage and cargo at airports.
No, it isn't! The point is, there is nothing new in the physics of this process! It's been around a long time. We know how it works. This reaction isn't going to be the one used, if fusion is ever developed on a practical scale, to produce usable energy. Look at the Q for this reaction, the cross-sections involved, and what is being produced, versus more practical reactions.
The thing that was significant about the Wright Brothers was their use of a relatively compact, high-power engine, combined with lightweight materials and somewhat revolutionary flight controls. We're going to need to solve a different breed of problem to make fusion practical.
Can it be done? Well, hell, I don't know. As the famous philosopher Yogi Berra once said, predictions are always hard, especially about the future. But the thing I am skeptical about, as others have noted, is that "break-even" fusion has been 20 years away, for the last 50 years.
"you want some souvenirs?"
Well, if you're gonna be up that way sure.
There is an international effort but I don't know the status of it. Check www.iter.org for more information. It's all just paperwork right now (i.e., "design studies"). This country seems to have given up on it (fusion) except as an international partner.
And don't get me started on what the brutal combine of candle-makers did to poor ol' Thomas Edison.
That sure is a strange looking lava lamp there in your living room.
Ahem...The "Incredible" Curta Type 1 "took out" the slide ruler... :))
You may have been producing neutrons, but you certainly were not generating them via a fusion process.
You were likely making unstable heavy isotopes by firing light elements into heavier ones; said unstable isotope then decays to lighter isotope of element x with the ejection of a neutron.
BTDT; Ion implantion was my game for 30 years.
And we have to find the He-3. Not quite as abundant as H-2, is it?
He-3 is rarer than hen's teeth! He itself is not that abundant, but He-3 constitutes only 0.00013% of all He.
H, of course is very abundant and H2, though rare, amounts to 0.015% of all H. That makes its relative isotopic fraction 3 orders of magnitude greater than He-3.
Above info is from my old (40+ years) chart of the nuclides, but I doubt the data have changed significantly.
In theory the fusor is perhaps the most promising form of fusion reactor studied. Energy is added to the fuel directly through acceleration, as opposed to the various indirect means required in a Tokamak or similar magnetically confined systems. Better yet, since the fusor is accelerating the ions (or electrons) directly, the range of velocities (or temperatures) is quite narrow. This means that most of the ions have enough energy to undergo fusion, whereas in a magnetically confined system it is typically only the "hottest" ions that can. Finally, failed collisions scatter inside the reaction area, heating other ions around them, thereby returning some of the energy to the reaction.Another advantage to the fusor is that any ion can be accelerated easily, not just the "low temperature" mixes like D-T. This makes the fusor particularly useful when running on other potential fusion fuels with much higher threshold temperatures. One of the most attractive such combinations is the proton - boron-11 reaction, which uses cheap natural isotopes, produces only helium, and produces neither neutrons nor gamma rays. This is a very clean reaction that would dramatically reduce waste when decommissioning a plant, and there is considerable interest in such aneutronic fuels.
Nothing in fusion is ever easy however. In the fusor a number of problems conspire to rob energy from the ions as they move towards the reaction area. One problem is the presence of "cooler" unionized particles of gas in the system, which can collide with the ions and cool them. Another problem is the presence of the inner electrodes, since ions often hit them and spray the reaction area with high-mass ions which soak up considerable energy from the surrounding fuel through collisions and then radiate the heat away as X-rays. This problem plagues traditional fusion designs as well, where it is known as sputtering.
A more serious concern was first outlined in 1994. In his doctoral thesis for MIT, Todd Rider did a theoretical study of all non-equilibrium fusion systems, of which the fusor is one of many. He demonstrated that all such systems will leak energy at a rapid rate due to Bremsstrahlung, radiation produced when electrons in the plasma hit other electrons or ions at a cooler temperature and suddenly decelerate. The problem is not as pronounced in a hot plasma because the range of temperatures, and thus the magnitude of the deceleration, is much less.
In most of the systems that he studied, the energy radiated away from the system was greater than the energy of the fusion itself. Unless a significant amount of energy from this radiation, namely X-rays, was captured, the system would never "break even". The problem is dependent on the mass of the fuel ions, so D-T and D-D fuels still provide net energy, but many of the more interesting aneutronic fuels appear to be impossible to use as an energy source.
Actually, if it produced a reasonable amount of net energy, you could just gang a potload of them together and you'd have your large quantities. It looks to me like the apparatus could be made by some sort of micro machining, similar to semiconductor manufacturing processes, which would allow you to make lots of little "reactors" fairly easily. You could probably just recycle the container, and the "fusion chips" as well when the container got brittle.
the chile i ate two or three years ago and left in the back of my refrigerator has definitely begun to undergo nuclear fusion...
Rumor has it that they are in Hanger Thirteen, but I have it on good authority that they were moved to the basement of the "Foreign Aerospace Science and Technology Center" (FASTC) HQ, building 828 when it was constructed in 1956. When I was there in the mid 80s, it was known as the Foreign Technology Division (FTD), but earlier, during the UFO era it was called the Air Technical Intelligence Center(ATIC) The information was on a bulletin board inside the highly secure facility. The ATIC was the home of Project Bluebook, the official Air Force investigation of UFOs. Did I mention that the ATIC/FTD/FASTC building is built on a slab? Hmmmm!
Building 828 circa 1965
(It was little changed externally in the mid 1980s)
What we really need to speed things up is a worthy adversary(s) and eminent demise! Near death concentrates the mind wonderfully.
Fission power went from first controlled chain reaction (Fermi's pile at Univ of Chicago in late '42) to viable controlled power production in the prototype submarine reactor at the Idaho National engineering lab in early 1953. That's just slightly over 10 years from first 'proof of concept' to useful device.
Ah well, maybe when oil hits $1,000/bbl we'll feel a bit more pressure to get off out collective duffs and get serious.
Tut, tut! The Farnsworth fusor is a hot fusion device. It works by getting the nuclei to move fast enough to overcome their electrostatic repulsion.
The only working cold fusion method I know of is muon-catalyzed fusion. That approach uses muons to cancel out the electrical charges of the nuclei, which allows the (slow) nuclei to snuggle up really close together, so close that the Yukawa potential takes over, and they fuse.
"The Secret History of the Candle Cartel" -- coming to an Art Bell show soon!
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