Posted on 03/02/2002 4:54:40 PM PST by aculeus
NUCLEAR scientists will this week announce they may have achieved a controlled form of cold fusion, a technology that potentially offers humanity a limitless source of clean energy.
The researchers are to publish evidence suggesting they have successfully fused the nuclei of hydrogen atoms, so recreating the processes that take place within the sun.
Until now the only way to achieve fusion has been through nuclear weapons or in vast experimental machines that cost billions of pounds. Both depend on generating extremely high temperatures.
However, the latest research, by scientists at the American governments Oak Ridge National Laboratory and the University of Michigan, was done on a laboratory bench using relatively simple and cheap equipment at room temperature.
The study echoes the work of Professor Martin Fleischmann and Stanley Pons who, in 1989, announced they had achieved cold fusion at Southampton University but were ridiculed when no one could repeat their work.
Fleischmann and Pons made what many now see as a fatal mistake when they released their results at a press conference rather than having them scrutinised by other scientists before publication in an academic journal.
It is understood that Rusi Taleyarkhan from Oak Ridge, Fred Becchetti from the University of Michigan and their collaborator, Robert Nigmatulin, of the Russian Academy of Sciences, have repeated their work and subjected it to extensive peer review.
If confirmed, the discovery could rank among the most important since the dawn of the nuclear age. The scientists are, however, extremely cautious at this stage, saying only that they have detected all the signs of fusion rather than categorically confirming it.
Their technique uses pressure waves to generate tiny bubbles in a solution of acetone that has been infused with deuterium, a heavy form of hydrogen extracted from sea water.
At the heart of most hydrogen atoms is a nucleus comprising a single proton. Deuterium atoms, however, have an additional particle, a neutron. This makes them roughly twice as heavy and slightly unstable.
Physicists have long known that smashing two deuterium atoms together can fuse them into tritium, a third form of hydrogen with a proton and two neutrons. This fusion releases vast amounts of energy. This was the principle used to create the hydrogen bomb in 1945, but ever since then scientists have been struggling to find a way to control the process.
In the latest technique, the sound waves create bubbles that expand with explosive force. As the wave passes, the bubbles implode, generating extremely high temperatures. This process is known as sono-luminescence after the flashes of light emitted.
Until recently scientists could generate only temperatures of tens of thousands of degrees, far short of the suns 10m Celsius. This appears to have been solved by hitting the bubbles with another sound wave that compresses them so rapidly that temperatures soar and the deuterium fuses.
An insider said the researchers had detected promising signs of fusion including the creation of tritium and, crucially, the emission of neutrons. The researchers believe the neutrons have energy levels consistent with those that would be emitted by deuterium fusion.
This would enable them to escape the fate of Fleischmann and Pons, whose readings of neutrons enabled them to claim they had achieved fusion. It later emerged that these neutrons could have been the results of contamination.
Neil Turok, professor of theoretical physics at Cambridge University, said the results, if confirmed, were extremely exciting: Cold fusion has a bad history but these laboratories are among the best in the world and they will have taken every precaution to get it right.
The research has major implications for other fusion projects. Britain already hosts the Jet project at Culham in Oxford, where a machine has been built to research sustainable nuclear fusion reactions.
This weekend it emerged that Culham had scrapped its own research into sono-luminescence and other low-tech forms of fusion after a report from Thornton Greenland, a former senior scientist, suggesting it was unlikely ever to work.
Greenland said: I thought there was too little evidence to show it would work, but this suggests I was wrong.
Recently, Lord Sainsbury, the science minister, committed Britain to joining an international project to build a £2 billion fusion machine called Iter, Latin for the Way.
Even this, however, will be able to sustain fusion reactions for only 16 minutes. A proper fusion reactor capable of producing power is thought to be 30-50 years away.
Fleischmann, who now lives near Salisbury, still believes his results were correct although he regrets allowing colleagues to press him into publicising them before he was ready.
He said: I hope they have achieved it. If they have, I hope people are ready for it this time.
And I'll finish up my cold fusion reactor, shortly after I perfect my "Infinite Improbability Drive," which, interestingly enough, seems to be required to get the cold fusion reactor to work...
Mark
You'll find that repeatability and predictability
are characteristics that distinguish science from
the I'll-believe-anything-you-tell-me-if-you-
say-Jesus-said-it standard of proof that passes
for you and your ilk, KC.
So where did you find enough unobtanium required to fuel it? :)
I have one of those things lying around my la-BOR-a-tory, somewhere. Or I did have. Or will have. (Durned time machine, always mixing me up!)
Gerry Yonas passed along your inquiry re: Z. We are continuing to make progress. Most recently, we completed the project to move the Beamlet laser from LLNL (Beamlet was the prototype laser for the national ignition facility). We were successful in reconstructing the laser next to Z and then synchronizing it within 3 ns to the peak radiation output from Z. We then were able, for the first time, to image imploding capsules with a backlighter. We have done some nice symmetry measurements of imploding capsules. We also have been working to refurbish the facility. This year, Congress supplied $10M (the first installment in what we hope to be a $60M total) to begin the refurbishment. When completed, we should have 26 MA into a z pinch (18 MA today) and 350 TW of x-ray power with 2.7 MJ of x-ray energy (200 TW and 1.8 MJ today). This will provide a significant improvement in precision, capacity and capability.
Finally, we are also using the Z facility to generate very high magnetic fields for materials studies. We have achieved 2 Mbar isentropic compression in Al and have launched flyer plates to greater than 26 km/s velocities. All in all a very versatile and useful machine.
Hope this answers your questions. We have a Web site http://www.sandia.gov/pulspowr/PPT.html that is a bit out of date but over the next few months we hope to bring it up to snuff.
Regards,
Jeff Quintenz
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