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Palladium and nuclear fusion

  1. Mar 3, 2007 #1
    Pons and Fleischman used a palladium cathode in their cold fusion experiment of 1989 (cathode immersed in heavy water,D20) and they said that excess energy was released from the system.
    Since 1989 lots of experiments have been done and some researchers have agreed with the findings of Pons and Fleischman.
    I have seen many explanations of why cold fusion can't take place according to known physics but here is one suggestion I have as to why it can!
    Palladium metal is very resistant to fracturing.This means that
    impurity atoms or ions face a high energy barrier to get into the crystal lattice and distort the face-centred cubic arrangement,and
    that it is difficult for defects to grow larger to cause fracturing.
    But when an electric current flows through palladium metal (which has hydrogen gas on its surface and inside it - palladium absorbs 900 times its own volume of hydrogen) hydrogen molecules and hydrogen ions (which are present in the heavy water) are given the energy to distort the metal structure and remain in situ.As time passes the number of distortions and hence the potential energy of the palladium cathode increases.At some critical point, the face-centred cubic arrangement of palladium atoms is quickly restored and the hydrogen molecules and ions are expelled from the palladium cathode as potential energy is released like a mini-earthquake.In a cylindrical-shaped cathode the released energy could be focused at its end or in the centre of the rod.In particular,at some locations in the rod where deuterium molecules are located, the focused energy could be sufficient to raise the temperature and pressure and cause helium 4 to form.The formation of helium inside the cathode would explain why nuclear products have rarely been detected in the heavy water, in experiments of this type.And the energy yield from fusion would be low because few deuterium atoms would get to the centre of the cathode by diffusion - most would be at or near the surface - the place where energy is least likely to be concentrated in order to raise the temperature and pressure enough for helium formation.
  2. jcsd
  3. Mar 3, 2007 #2


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    If we are talking He-4 produced in a "D-T" reaction; that is fusion of Deuterium and Tritium:

    D + T --> He4 + n + 17.6 MeV

    What happened to the neutron? The neutron gets 14.1 MeV of that 17.6 MeV of energy
    liberated. A 14.1 MeV neutron has a LONG mean free path because its interaction cross-
    section is so low.

    That 14.1 MeV neutron is going to escape. You can't compress the material enough to
    contain that 14.1 MeV neutron. Since the 14.1 MeV neutrons will escape; they should
    be streaming out of the electrolytic cell if there really is nuclear fusion underway. We
    don't see the neutrons - so there's no fusion underway.

    Additionally, it doesn't matter where the energy ends up - "inside" or "on the surface" as
    you point out above. Either way - we can detect the energy - be it the temperature of the
    material inside, or the temperature of the material on the surface, or energy escaping as
    radiation, for example.; from the surface - we should see it and measure it. We don't see it.

    The absence of both the energy and neutrons that one expects to see from the "D-T"
    reaction leads one to an inescapable conclusion - "D-T" fusion ISN'T happening.

    Dr. Gregory Greenman
  4. Mar 5, 2007 #3
    My fusion prof back in university (also a physicist) would get livid if anyone ever brought up Pons & Fleischman. As Dr. Greenman pointed out, the most obvious signs one would expect from the reaction those men, and others who follow in trying to replicate their experiments are trying to induce, are missing, thus leading to the obvious conclusion that the apparatus is not achieving what they claim it is.

    The last I heard of cold fusion was Dr. Rusi Taleyarkhan @ Purdue. This is bothersome to me because the circumstances surrounding his work have been tarnishing the reputation of an otherwise well-regarded nuclear engineering program.
  5. Mar 8, 2007 #4
    There is currently cold fusion research being undertaken in the UK at one of its well renowned technical & engineering universities, based on Taleyarkhan's work (sonofusion). One of the problems they are anticipating is distinction between the possible fusion-generated neutrons and the incident neutrons required. It will be good to enventually have the idea independently corroborated or refuted.
  6. Mar 9, 2007 #5
    It's Exothermic but not Fusion.

    By Occam's razor, one had to conclude that Pons and Fleschmann had to be either deceptive, or clumsy. We can't blame the established research infrastructure for not believing them.

    Strangely though, through more careful and duplicatable experimentation, it can now be seen that there is an exothermic reaction, and tracks recorded on CR-39 detectors indicate leptons at about 10MeV energies.

    Please point your seach engines toward "Widom and Larsen" and "Ultra Low Momentum neutrons" being generated on metallic hydride Surfaces; There really is a reaction, that may be very interesting to future research associates. I believe it is an excellent explanation of much of the phenonomon of "Cold Fusion" whereby Columb repulsion is not a barrier; although the Pauli principle is not addressed..... Check it out!
  7. Mar 9, 2007 #6


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    However, whatever the reaction is; it's NOT nuclear fusion.

    There may be some reactions via the electro-weak force.

    Lest one forget, the goal is to produce the large amount of
    energy freed when reactions involving the strong [nuclear] force
    are produced.

    Dr. Gregory Greenman
    Last edited: Mar 9, 2007
  8. Mar 11, 2007 #7
    You might find this interesting regarding "sonofusion".

    http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=PRLTAO000096000003034301000001&idtype=cvips&gifs=yes [Broken]

    Last edited by a moderator: May 2, 2017
  9. Mar 11, 2007 #8


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    Yes - I assisted a collegue, Dr. William Moss; in an analysis of "sonoluminescene" or

    The conlusion was that it was NOT inducing nuclear fusion.

    In fact, Dr. Moss twice REJECTED one of the papers on "sonofusion"
    when he was called upon to review it for the journals:

    http://www.asa.aip.org/vol12no2.pdf [Broken]

    From the American Institute of Physics website, Dr Moss makes
    the following evaluation:

    http://www.aip.org/pnu/2002/split/579-2.html [Broken]

    However, according to leading sonoluminescence theorist William Moss
    of Lawrence Livermore National Laboratory, "We are all pretty sure that
    normal SL conditions are nowhere near fusion temperatures--typical SL
    temperatures don't exceed 11,000 degrees Kelvin or so, at least from
    theoretical estimates"---as opposed to the millions of degrees that
    nuclear fusion would typically require.

    Sonofusion misses the temperatures required for nuclear fusion by
    two to three orders of magnitude.

    The thermonuclear fusion reaction D + T -> He4 + n has a very characteristic
    signature - the 14.1 MeV neutrons.

    Sonofusion doesn't produce 14.1 MeV neutrons; so it is NOT nuclear fusion occuring.

    "Sonufusion" is NOT nuclear fusion.

    Dr. Gregory Greenman
    Last edited by a moderator: May 2, 2017
  10. Mar 12, 2007 #9
    Taleyarkhin(how ever its spelled) idea was fascinating though. To bad it never worked in reality.:frown: But then again Sonoluminescence is fascinating on its own without the need for any fusion going on.
    Last edited by a moderator: May 2, 2017
  11. Mar 12, 2007 #10


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    Yes - it's a fascinating field of study.

    Unfortunately, it is "hyped" as a potential solution for energy production.

    It's also interesting how the "Cold Fusion" crowd has morphed over the years. They are
    mainly saying that "Cold Fusion" phenomenon may be due to some interaction via the
    "electro-weak" force. There may be something there. However, the "electro-weak" force
    is the same one that is responsible for regular chemical reactions.

    So any "Cold Fusion" reactions will have the same order of magnitude in terms of
    energy production, as chemical reactions.

    The big promise for energy production is something based on the nuclear force; because
    that yields, pound for pound; a MILLION times as much energy as derived from reactions
    based on the "electro-weak" force.

    Dr. Gregory Greenman
  12. Mar 12, 2007 #11
    Thanks. The Imperial College group are definitely using external neutrons, derived from a D-T generator somewhat ironically! I'll do some digging to see what the basis of their research is. Hopefully they are not flogging the proverbial dead horse.
    Last edited by a moderator: May 2, 2017
  13. Mar 31, 2007 #12
    Low Energy Nuclear Reactions are not "cold fusion"

    Dear Dr. Gregory and other participants:

    We wholeheartedly agree; "it's NOT nuclear fusion." In particular, and contrary to most of the existing “cold fusion” scientists, Prof. Widom and I believe that certain well-established anomalous experimental results (e.g. He-4 production, excess heat, transmutations) that have frequently been reported by researchers in the field since 1989 are best explained by invoking the weak interaction, not strong interaction fusion or fission. Our theoretical model of Low Energy Nuclear Reactions is outlined in four readily available papers listed below. No “new physics” is involved --- merely an extension of collective effects to electroweak theory within the context of the Standard Model. Thus, the phenomenon is not really “cold fusion” and never was.

    Please note that the weak interaction is not necessarily "weak" energetically speaking. Energy released by ultra low momentum neutron (ULMN) catalyzed nuclear reactions can be quite substantial. For example, see Eqs. 30 and 31 in our EPJC paper; these particular reactions release > 26 MeV. There are known beta decays that are > 20 MeV. So by choosing the right "targets" for ULMN neutron absorption, you can achieve net energy releases that approach those of the D-D and D-T fusion reactions. However, there are no large releases of energetic neutrons (ULMNs are almost all captured locally before they can thermalize) or hard gamma radiation (gammas between ~1 MeV and 10 MeV are directly absorbed by mass-renormalized SPP electrons and reradiated as mostly infrared photons).

    Lastly, ULM neutrons have huge DeBroglie wavelengths because they are formed collectively in many-body surface "patches" of protons or deuterons. Depending on the size of a particular "patch", ULMN wavelengths can be as large as 50,000 to 100,000 Angstroms. No joke. By comparison, a free neutron passing through condensed matter would typically have a wavelength of ~ 2 Angstroms. So the capture cross sections for ULM neutrons on many "target" isotopes is orders of magnitude larger than for neutrons at thermal energies. This is why large fluxes of much more energetic (thermal to MeV+) neutrons have never been seen in 18 years of experimental work on LENR systems. The absence of substantial external emissions of hard photon radiation produced in conjunction with local neutron captures and some (not all) beta decays is explained by local direct conversion of gammas by mass-renormalized "heavy" surface plasmon polariton (SPP) electrons.

    The main problem for most researchers in the "cold fusion" field is that for 18 years they have been working with a D-D fusion paradigm locked firmly in their minds. Unfortunately, in our view, that conceptual paradigm was wrong. So much effort was misdirected and many otherwise good experimental results were misinterpreted --- this contributed to the "wheel spinning" and terrible frustration that has characterized the field since 1989.

    Hope that this helps clarify a few points. For further details, please read our papers if you have time.

    "Ultra low momentum neutron catalyzed nuclear reactions on metallic hydride surfaces"
    Eur. Phys. J. C 46, 107-111 (2006)

    "Absorption of Nuclear Gamma Radiation by Heavy Electrons on Metallic Hydride Surfaces"

    "Nuclear Abundances in Metallic Hydride Electrodes of Electrolytic Chemical Cells"

    "Theoretical standard model rates of proton to neutron conversions near metallic hydride surfaces"
  14. Mar 31, 2007 #13


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    I would agree with your assessment. Ever since the early days of "cold fusion"; I've always
    contended it was probably a chemical [Coulomb] or "weak" interaction.

    It always seemed that the chemists exploring this phenomenon cited it as being a
    nuclear reaction by "default".

    In essence; "I did this experiment which yielded results that I can't explain via my
    knowledge of chemistry; so the reactions must be nuclear, which is a field I don't know
    anything about."

    It didn't look "nuclear" to me; and I know what nuclear looks like. I figured sooner or
    later it would turn out to be some interesting, and heretofore unknown, or unexplored;
    chemical or "weak" interaction - and we have learned something.

    Dr. Gregory Greenman
  15. Apr 24, 2007 #14
    The term "cold fusion" was not a wise choice of words for this research in 1989, nor is it now. The hypothesis of a fusion reaction is still speculative, there are numerous anomalies reported in the research that clearly are not fusion, and then there is the Widom-Larsen Not-Fusion theory.

    New Energy Times has been reporting on the Widom-Larsen theory for several years. Our comprehensive ongoing analysis of this theory can be found at http://newenergytimes.com/wltheory [Broken].

    Steve Krivit
    Editor, New Energy Times
    Last edited by a moderator: May 2, 2017
  16. May 16, 2007 #15


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    Granted the absence of the 14MeV N. demands skepticism. But, given the many reports of the presence of He from the beginning, it seems to me that neither can the idea of some kind of non-chemical reaction occurring be dismissed. "Well its not uniformly repeatable". Again, that warrants skepticism not dismissal. In my field (EE) the early development of doping for semiconductors and integrated circuits produced frustratingly non repeatable results. If everyone had followed the banner of 'scam, run them out of town' we'd still be using tubes.

  17. May 17, 2007 #16


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    Although one may not be able to dismiss some kind of "non-chemical" reaction occurring;
    I believe we CAN DISMISS this as a "nuclear reaction" - that is "nuclear" as in relating
    to the "strong force".

    The observed reactions just don't look like "nuclear reactions".

    Something along the lines of a reaction from the "electro-weak" force as suggested by
    Larsen, above is plausible.

    As Larsen states above, "..it's NOT nuclear fusion"; and I concur.

    Dr. Gregory Greenman
  18. Sep 2, 2007 #17
    Here is a web site with numerous reports of LENR (low energy nuclear reactions):

    http://www.lenr-canr.org/index.html [Broken]
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  19. Sep 4, 2007 #18


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    I'm familiar with this work. However, even those scientists don't claim the effect is a nuclear
    reaction - in the sense that the reaction is due to the strong nuclear force.

    Instead, they claim it is a manifestation of the "electro-weak" force - the unification between the
    Coulomb force and the weak force.

    The difference is important in terms of energy production. Reactions based on the "electro-weak"
    force give approximately 1 eV of energy per amu of reactant - the same as any other chemical

    Fusion reactions via the strong nuclear force result in energies of 3 Million eV per amu of reactant.

    The whole reason for wanting a nuclear reaction is that MILLION+ factor of energy release; which
    one doesn't get from ANY claimed "cold fusion" mechanism.

    Dr. Gregory Greenman
  20. Feb 10, 2008 #19
    energy release

    Dr. Greenman:

    Larsen writes: "not necessarily 'weak' energetically speaking"

    You write: "I figured sooner or later it would turn out to be some interesting, and heretofore unknown, or unexplored; chemical or 'weak' interaction."

    There was a time when I accepted - as it was told to me - the assertion/speculation that a fusion mechanism was responsible for the observed anomalies in what I now call LENR research. Eight years of journalistic investigation later, I am less willing to accept that hypothesis.

    I understand that chemical energy is on the order of a million times less than nuclear fusion energy. From my investigations, I remain convinced that the numerous experimental reports I have come across which show energy release on the order of a thousand times more than you would expect from a chemical process remain rigorous.

    I would like to know your perspective on Larsen's assertion that this "weak interaction" idea is a potentially significant energy-releasing process.

    Thank you,
    Steve Krivit
    Editor, New Energy Times
    Last edited by a moderator: Feb 13, 2008
  21. Feb 10, 2008 #20


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    Sbkrivit: that indeed seems to be prevailing opinion. If you are current on the state of investigation could explain why? (ie why it can't fusion) http://www.lenr-canr.org/acrobat/SchwingerJcoldfusionb.pdf" [Broken] in the 90's. Has Schwinger's hypothesis been shown to be wrong? -

    1st he suggests the reaction may be p + D -> He3 + 5MeV gamma. Therefore no neutrons required. As for the gamma he suggests it may be absorbed by the Pa lattice.:
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