Posted on 09/04/2001 2:02:26 PM PDT by blam
Cold fusion experiment produces mysterious results
15:10 04 September 01
Jeff Hecht
A "cold fusion" experiment in California has produced tantalising results - but critics say they may not indicate that cold fusion has actually taken place.
Most physicists treat claims of cold fusion with derision. However, an underground of enthusiasts has continued performing experiments which, they say, demonstrate that deuterium nuclei can fuse to produce tritium and helium isotopes during the electrolysis of heavy water with palladium electrodes. The few outsiders who have tried to repeat the experiments have failed, and claims for cold fusion have not survived peer review to appear in mainstream journals.
Now Brian Clarke of McMaster University in Ontario, Canada, has found something that is not easily explained away.
Researchers at SRI International, a private laboratory in California, carried out a cold fusion experiment - passing a current through heavy water using palladium electrodes - and claimed to see more heat produced than could be explained by the electric power used. They then sent their electrodes to Clarke for analysis. He discovered that they contained more than 1015 atoms of tritium, a heavy radioactive isotope of hydrogen.
"There's no question of the tritium being real," Clarke told New Scientist.
"No explanation"
Although this is more tritium than you would expect to find in a palladium electrode, it is still about 20,000 times less than the amount that would have been produced if the excess heat observed in the SRI experiments had been produced by the fusion of deuterium nuclei, as cold fusion advocates predict. They also predict that helium should be produced in these fusion reactions, but Clarke saw no evidence of helium in the electrodes.
"I have no explanation of how the tritium was produced," Clarke told New Scientist.
Michael McKubre, who performed the SRI experiments, says: "I am not convinced it's a fusion process, but it's definitely a nuclear process."
A spokesman for the UK Atomic Energy Authority's Culham Laboratory who has seen Clarke's analysis said the small amount of tritium "indicates it's an electrochemical effect"--that the heat is produced by the making or breaking of chemical bonds rather than the fusing of nuclei.
Clarke also investigated similar experiments led by Yoshiaki Arata of Osaka University, Japan. Arata's team claimed to have detected an excess of helium-3 and helium-4 isotopes following the heavy water electrolysis. But Clarke's analysis revealed no excess.
Journal reference : Fusion Science and Technology (Vol 40, p 147, 152)
prisoner6
I still keep newspaper clippings of the original reports from the U. of Utah experiments. It hasn't been explained away...(in my book).
Ashland, Missouri
No doubt, but how well did they rid the heavy water of tritium in the first place? And did they repeat this experiment with light water, which cold fusion advocates contend should not show a positive result? How much tritium did they see in that control experiment?
What is the distribution of tritium measurements from a series of trials with heavy and light water, and how do they compare to the tritium found in a series of "new" palladium rods?
How much tritium is found when a different metal is used? What should we expect?
The only thing that's clear from this article is that the nuclear processes they are claiming to have seen are not responsible for the excess heat they are claiming to have seen.
I'm sure he means the excess heat was generated electrochemically. As for the "excess" tritium -- being off by a factor of 20,000 is, in my humble opion, being off by a significant amount. I'm going to keep my connection to the power grid for a while.
Careless calorimetry seems to be the most likely explanation. In any case, Pons and Fleischman apparently still buy their power from the power company.
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This statement is entirely incorrect.
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Yes.
The "15" should be superscripted -- that's 1 quadrillion (thousand billion if you're a Brit) atoms. Not enough to explain the claimed heat production, but still mighty peculiar. The number should have been a lot closer to zero.
The Pons and Fleischman paper is worth reading. The guys didn't just stumble into their "finding." Rather, they predicted on the basis of hydrogen's coulomb barrier and how tightly hydrogen packs into palladium that probability of fusion might be significant.
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