Thermal behavior of polarized Pd/D electrodes prepared by co-deposition
S. Szpak · P. A. Mosier-Boss · M. H. Miles · M. Fleischmann
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In one page
Stanislaw Szpak and Pamela Mosier-Boss of the US Navy’s SPAWAR laboratory, with Melvin Miles and Martin Fleischmann, ran a palladium and deuterium electrode built by co-deposition — the metal and the deuterium plated down together onto a copper rod, so the film arrives already loaded — inside a Dewar calorimeter, and measured its heat. They report that the cell released more heat than the electrical input accounts for: about 75 kilojoules integrated over the run, at rates somewhat higher than solid palladium electrodes give and with no incubation period before the effect appears. Two further behaviours make the paper interesting. Switch a small calibration heater on and off, and the cell sometimes fails to relax to the temperature it should, while the excess climbs — positive feedback. Step the current down, and heat keeps arriving for hours afterwards — heat after death. The team sets gas recombination aside, because the gas they collected matched the electrical prediction to within one per cent.
Why it matters hereChapter 12 follows lattice confinement fusion and the calorimetry every claim in it rests on, and chapter 1 is the evidence ladder. This is the measurement the whole Thermochimica Acta exchange turns on, and it is where positive feedback and heat-after-death enter the record as things a calorimeter can be asked about directly.
What it claims
01A palladium and deuterium electrode prepared by co-deposition generates excess enthalpy both during and after the co-deposition process, at rates somewhat higher than solid palladium wires or other palladium electrode forms give, and without the incubation period those electrodes need.Abstract, points (i) and (ii); Section 4, opening
Published and peer-reviewed02The eleven-point average of the excess enthalpy generation integrated over the duration of the experiment comes to 75 kilojoules, computed from the Dewar cell equation with a heat transfer coefficient of 0.85065 × 10⁻⁹ watts per kelvin to the fourth power and a water equivalent of 450 joules per kelvin, both fixed for that cell in advance.Section 4.1 and Fig. 3; parameters in Section 3.2
Published and peer-reviewed03Applying a 0.2500 watt calibration pulse produces two different responses in the same run: in one the temperature rises exponentially and relaxes back to the sloping line at a constant excess rate of 0.24 watts, and in the other the temperature does not relax to the expected value at all, with the cell voltage falling and the excess rising from 0.05 to 0.14 watts — which the authors read as positive feedback.Section 4.2 and Fig. 4a, 4b
Published and peer-reviewed04After the charging current is stepped down from 0.2 amperes to 0.05 and then to 0.02 amperes, the excess enthalpy decays over the following period rather than stopping, which the authors call heat-after-death; in constructing that decay they take the upper bound of any parasitic excess from recombination to be 0.009 watts, the last value of the averaged excess at 24 hours, so the plotted values are lower bounds.Section 4.3 and Fig. 5
Published and peer-reviewed05The authors set aside recombination of the evolving deuterium and oxygen as the heat source on two grounds: collected gas volumes were within 1.0 per cent of those calculated for 100 per cent Faradaic efficiency, with total heavy-water consumption of 7.7 cubic centimetres against 7.2 computed; and Fleischmann and Pons had estimated that short-lived hot spots of the kind their infrared camera records would carry about 6 nanowatts, too faint for such a camera to see.Section 2.3; Section 4.1, recombination paragraph
Published and peer-reviewed06The calorimeter itself is the quantity the dispute turns on: the authors cite Hansen and Melich’s independent evaluation that Dewar cells of this type are easily capable of 1.0 per cent accuracy, with radiation dominating heat transfer from 20 to 60 degrees Celsius, radial mixing in 3 seconds and axial in 20, and a single heat transfer coefficient carried across runs — while the comment sheet stm-190538cb53 argues that a calorimeter with two regions of different heat-capture efficiency shifts that constant when heat moves between them, so the named next measurements are the calorimeter’s true noise level and an independent replication of the positive-feedback and heat-after-death runs.Section 2.5, characteristics (i) to (ix); Section 5, Concluding remarks
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https://doi.org/10.1016/s0040-6031(03)00401-5Thermochimica Acta 410 (2004) 101–107, received 16 December 2002, accepted 16 July 2003, carrying the line ‘© 2003 Elsevier B.V. All rights reserved.’ The copy read for this sheet is the one at lenr-canr.org, which is headed ‘Reprinted with permission from Elsevier.’ Permission to host a copy is not a redistribution licence, so no text of the paper is reproduced here; the summary and the claims below were written from that full published text. Three companion sheets are read with this one: Kirk Shanahan’s 2005 comment on this paper is stm-190538cb53, his 2002 mass-flow calorimetry paper is stm-bc8d23c500, and his 2006 reply to Edmund Storms is stm-89fb30b1b3. Szpak’s own account of the co-deposition method is stm-344232fcb0.
How to cite it
S. Szpak, P. A. Mosier-Boss, M. H. Miles, M. Fleischmann (2004) Thermal behavior of polarized Pd/D electrodes prepared by co-deposition. doi:10.1016/s0040-6031(03)00401-5
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