On March 23, 1989, they announced at a news conference at the University of Utah that they had discovered a tabletop process for producing nuclear fusion at room temperatures. This so-called cold fusion, they said, would provide a clean, renewable, limitless source of cheap energy that could free the United States from its dependence on foreign oil.
The pair garnered headlines around the world, and literally hundreds of scientists, both professional and amateur, tried to replicate what appeared to be a simple process.
But no one could. The mainstream scientific world echoed the conclusion of physicist Steven E. Koonin of Caltech, who called the initial report the result of "the incompetence and delusion of Pons and Fleischmann."
After attempting — and failing — to reproduce the results for several years, Fleischmann retired to his home in England, where he died Aug. 3 of Parkinson's disease and diabetes, his son Nicholas told the Associated Press. He was 85.
Nuclear power is now produced in plants powered by fission, in which atoms of uranium or plutonium decay naturally to produce heat that drives steam generators. Producing energy through nuclear fusion, the same process that occurs in the sun, remains an elusive goal.
In fusion, two or more atomic nuclei join to produce a heavier element, releasing energy in the process. In most research efforts, physicists have tried to fuse an atom of deuterium — heavy hydrogen — with one of tritium to produce helium. Because deuterium and tritium are abundant in the world's oceans, albeit at low levels, fusion could provide a limitless source of energy.
But forcing the nuclei to combine requires high temperatures and pressures, and experimental fusion reactors typically produce less energy than is required to fuse the atoms.
Pons and Fleischmann thought they had found a much simpler way, using what chemists call electrolysis. It's simple in concept: Two electrodes are immersed in a conductive solution and electricity is passed between them. In a simple electrolysis cell, the reaction splits water to form hydrogen at one electrode and oxygen at the other.
The team became convinced that if they used the right electrodes and immersed them in deuterium oxide instead of plain water, the freed deuterium atoms would become packed into an electrode, where they would fuse. At the news conference, they reported that their simple cells released more energy than was put into them — in other words, that fusion had occurred.
Others immediately saw problems. If deuterium-deuterium fusion was occurring, the process should release energetic neutrons. Nobody was ever able to detect such neutrons. The process should also produce helium by the fusing of the deuterium atoms. The team was never able to show excess quantities of helium beyond what was in the background air.
And, perhaps most important, other scientists concluded that Fleischmann and Pons had botched their energy calculations and that no excess energy was being produced.
The men always claimed that they were rushed into a premature announcement of their findings, without scientific publication, by University of Utah President Chase N. Peterson, in large part because a rival team at Brigham Young University was working on a similar project. Peterson became a cheerleader for their work and helped persuade the Utah Legislature to grant them $5 million for research. The university spent more than $1 million in legal fees to patent the research.
But within two years, cold fusion was dismissed by the scientific community, Peterson had resigned and Pons and Fleischmann had left Salt Lake City for France, where they had less notoriety.
They continued their work at Techova Corp., a subsidiary of Toyota, with more than $30 million in research funds but never replicated their earlier findings. They parted ways under less than amiable conditions in 1995 when Fleischmann retired.
Pons has essentially disappeared from sight.
A near cult has arisen around cold fusion, and many amateur scientists still claim to have produced the effect. Their research has been dismissed by the scientific community.
Martin Fleischmann was born March 29, 1927, in Karlovy Vary, Czechoslovakia, and moved to England in 1938 with his family to escape the Nazis. He received a doctorate in chemistry from Imperial College London in 1950, the year he married Sheila Flinn, a painter and potter. The couple had three children.
He taught at the University of Newcastle upon Tyne and the University of Southampton, where he was a respected electrochemist. He played a crucial role in the development of a spectroscopy technique called surface enhanced Raman scattering and was the developer of the ultramicroelectrode.
When he retired from teaching in 1983, he moved to Salt Lake City to work with his former student, Pons.
Twitter/@LATMaugh
No hay comentarios:
Publicar un comentario