Calorimetry in cold fusion experiments

Calorimetry in cold fusion experiments

Calorimetry is an essential part of cold fusion experiments.

Cold fusion researchers use different types of calorimeters: isoperibolic, flow, Seebeck. [harvnb|Storms] The accuracy of the calorimetry has been critiqued by Lewis,cited in harvnb|Browne|1989|loc=para. 16.] Wilson, harvnb|Wilson|1992] Shkedi,harvnb|Shkedi et al.|1995|Ref=Shkedi1995.] Jones,harvnb|Jones et al.|1995|Ref=Jones1995|p=1] and Shanahan [harvnb|Shanahan|2002] [harvnb|Shanahan|2005] [harvnb|Shanahan|2002] .

Cold fusion researchers find these critique unconvincing, and not applicable to other experimental design.harvnb|Fleischmann|1992|Ref=Fleischmann1992] [harvnb|Will|1997|p=177.] harvnb|Storms|2007|p=195.] [harvnb|Storms|2006.]

Critique

hkedi and Jones

In some electrolysis cells running at low voltage, internal recombination of hydrogen and oxygen can create the appearance of excess heat. This is called the "Faraday-efficiency effect".

In 1991-1993, a group of investigatorsharvnb|Shkedi et al.|1995|Ref=Shkedi1995|pp=1720-1731.] [harvnb|Shkedi|1996|Ref=Shkedi1996|p=133.] led by Zvi Shkedi built well-insulated light-water electrolysis cells and calorimeters which included the capability to measure the actual Faraday efficiency in real time. The average Faraday efficiency measured in these experiments was 78%. With this taken into account, the calculated excess heat was 0.13% +/- 0.48% of input power. If instead a Faraday efficiency of 100% was assumed, the apparent excess heat was 21%. The investigators concluded "All reports claiming the observation of excess heat should be accompanied by simultaneous measurements of the actual Faraday efficiency."harvnb|Shkedi et al.|1995|Ref=Shkedi1995.]

Jones et al. confirmed the Shkedi et al. findings and concluded: "Faradaic efficiencies less than 100% during electrolysis of water can account for reports of excess heat in 'cold fusion' cells."harvnb|Jones et al.|1995|Ref=Jones1995|p=1.]

Fritz Will, former president of the Electrochemical Society, noted in his review of Jones' paper that " [the] fraction of O2 recombining with H2 decreases significantly with increasing current density. [...] On the basis of their results at low current densities, a group of researchers recently concluded that H2 + O2 recombination is the source for the "excess heat' reported by other groups and attributed by some to 'cold fusion'. However, reported excess heat values, ranging from a low of 23% at 14 mA/cm2 to a high of 3700% at 6 mA/cm2, are much larger than can be explained by recombination. Whatever the explanation for the large amounts of excess heat reported by various groups, H2 + O2 recombination must be rejected as a tenable explanation." [harvnb|Will|1997|p=177.]

Edmund Storms labeled Jones' conclusions "a good example of biased reasoning", observing that " [Jones et. al.] measured the recombination fraction at very low currents, where [uncertainty] is high, and used these values to dismiss all measurements using open cells, without acknowledging that most successful studies used much higher currents or closed cells where this correction is unnecessary."harvnb|Storms|2007|p=195.]

Fleischmann measured Faraday efficiency in his cold fusion experiments and found it to be better than 99%.harvnb|Fleischmann et al.|1990|Ref=Fleischmann1990|p=301.]

hanahan

In 2002, Shanahan speculated the apparent excess heat signals were arising from a systematic error he called the calibration constant shift (CCS). [harvnb|Shanahan|2002.]

Shanahan reanalyzed calorimetric data provided by E. Storms under the assumption that no excess power was in fact present, and found that a minor (1-3%) change in the calorimeter calibration constants was all that was required to explain the apparent excess power. [harvnb|Shanahan|2002.] Shanahan also proposed that the cause of the shift was a redistribution of heat in the apparatus, which is similar to one of the earlier complaints against Fleischmann-Pons type of calorimetry (single point temperature measurement being suceptible to hot spots). Shanahan further speculated that such a redistribution might arise from unexpected hydrogen-oxygen recombination at the electrode.

In July 2003, Szpak, in a paper co-authored with Fleischmann, said that such recombination reaction is not supported by experimental results. [harvnb|Szpak|2004|Ref=Szpak2004.] Shanahan replied that the recombination Szpak and Fleishmann were discussing was not what Shanahan was discussing, and was therefore irrelevant. [harvnb|Shanahan|2005.] Three years later, Storms said that even when a large change in where a large amount of heat is generated within the cell is made on purpose in a flow calorimeter, little or no effect on the calibration constant is observed. [harvnb|Storms|2006.] Shanahan responded to Storms in a back-to-back publication that Storms' own data displayed just such effects and that such effects were capable of explaining Storms' excess heat signals. [harvnb|Shanahan|2006.] His response included a breakdown of the 10 experimental runs into 4 sequential sets based on what seemed to be a clear time-dependent shift or reset in the calibration constants. This time dependence suggests a chemical aging effect that was reversed by in-cell processing, further emphasizing the non-nuclear nature proposed by Shanahan. He concluded that the chemical explanation he presented deserves an honest experimental test.

In his book, Storms said that the 1.2 % variation of the calibration constants he measured proves that the calibration errors proposed by Shanahan are absent.harvnb|Storms|2007|p=41.] He also said that Seebeck and flow calorimeters are immune to these potential errors, although the isoperibolic method can be affected.harvnb|Storms|2007|p=172.] However Storms' book did not analyze Shanahan's final latest publication, which refuted these same points. [harvnb|Shanahan|2006.]

His final conclusion is that the conventional explanation for apparent excess heat must be tested along with the unconventional, 'cold fusion' explanation.

References

Bibliography

*citation|last=Browne|first=M.|title=Physicists Debunk Claim Of a New Kind of Fusion| journal=New York Times| date=May 3, 1989 |year=1989| url=http://partners.nytimes.com/library/national/science/050399sci-cold-fusion.html| accessdate = 2008-05-25.

*citation|ref=Fleischmann1990|last=Fleischmann|first=Martin|last2=Pons|first2=Stanley|last3=Anderson|first3=Mark W.|last4=Li|first4=Lian Jun|last5=Hawkins|first5=Marvin|title=Calorimetry of the palladium-deuterium-heavy water system|journal=Journal of Electroanalytical Chemistry|volume=287|year=1990|pages=293-348

*citation|ref=Fleischmann1992|last=Fleischmann|first=Martin|last2=Pons|first2=Stanley|title=Some Comments on The Paper 'Analysis of Experiments on The Calorimetry of Liod-D2O Electrochemical Cells,' R.H. Wilson et al., Journal of Electroanalytical Chemistry, Vol. 332, (1992)",|journal=Journal of Electroanalytical Chemistry|volume=332|year=1992|pages=33

*citation|ref=Jones1995|last=Jones|first=J. E.|last2=Hansen|first2=L. D.|last3=Jones|first3=S. E.|last4=Shelton|first4=D. S.|last5=Thorne|first5=J. M.|title=Faradaic efficiencies less than 100% during electrolysis of water can account for reports of excess heat in`cold fusion` cells|year=1995|journal=Journal of Physical Chemistry|volume=99|issue=18|pages=6973-6979

*citation|last=Shanahan|first=Kirk|title=A systematic error in mass flow calorimetry demonstrated|journal=Thermochimica Acta|volume=382|issue=2|year=2002|pages=95-101.

*citation|last=Shanahan|first=Kirk|title=Comments on "Thermal behavior of polarized Pd/D electrodes prepared by co-deposition"|journal=Thermochimica Acta|volume=428|year=2005|pages=207-212.

*citation|last=Shanahan|first=Kirk|title=Reply to “Comment on papers by K. Shanahan that propose to explain anomalous heat generated by cold fusion”, E. Storms, Thermochim. Acta, 2006|journal=Thermochimica Acta|volume=441|issue=2|year=2006|pages=210-214.

*citation|ref=Shkedi1995|last=Shkedi|first=Zvi|first2=R.C.|last2=McDonald|first3=J.J.|last3=Breen|first4=S.J.|last4=Maguire|first5=J.|last5=Veranth
title=Calorimetry, Excess Heat, and Faraday Efficiency in Ni-H2O Electrolytic Cells.|journal=Fusion Technology|volume=28|issue=4|year=1995|pages=1720-1731
.

*citation|ref=Shkedi1996|last=Shkedi|first=Zvi|title=Response to Comments on 'Calorimetry, Excess Heat, and Faraday Efficiency in Ni-H2O Electrolytic Cells'|journal=Fusion Technology|volume=30|issue=???|year=1996|page=133.

*

*citation|last=Storms|first=Edmund|title=Comment on papers by K. Shanahan that propose to explain anomalous heat generated by cold fusion|journal=Thermochimica Acta|volume=441|issue=2|year=2006|pages=207.

*citation|last=Storms|first=Edmund|title=Science of Low Energy Nuclear Reaction: A Comprehensive Compilation of Evidence and Explanations|location=Singapore|publisher=World Scientific|year=2007|ISBN=9-8127062-0-8.

*citation|last=Will|first=F. G.|title=Hydrogen + oxygen recombination and related heat generation in undivided electrolysis cells|journal=Journal of Electroanalytical Chemistry|volume=426|issue=1|year=1997|pages=177-184.

*citation|last=Wilson|first=R. H.|title=Analysis of experiments on the calorimetry of LiOD-D2O electrochemical cells|journal=Journal of Electroanalytical Chemistry|year=1992|volume=332|pages=1–31.


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