Kitamura et al. have been working on gas loaded Pd and Ni for some time,
originally in a replication of Arata's Zr+Pd alloy.

Kitamura's experiment looks much better to me than it did last year. They
finally made a precision flowmeter. It holds a much larger sample of
powder. It is about time they scaled up the sample size. It can be run at
high temperature with reasonable accuracy. I think they are now getting
more heat from the Ni alloys than Pd. They get 20 to 30 W from Ni. It only
works at high temperatures, as I recall around 300 deg C. One lesson from
the last few years is that if you want to make Ni work, you need a high
temperature.

I have a few concerns about the calorimetry, but that is probably because I
am unfamiliar with some aspects of it, to wit:

They are using oil instead of water as the working fluid. It is a good
choice for such high temperatures, but I have not used it myself so I can't
judge. I am a little concerned about a curve they showed from the
manufacturer of heat capacity and viscosity at different temperatures. It
varies a great deal. You have to trust the manufacturer on this.

The flow rate is only 20 ml/min. That would be too slow with water. I don't
know about oil.

They measure the temperature on the outside of a small copper pipe. I guess
that should work but I don't see why they did not use a T. Again . . .
maybe that is not a good idea with oil? I have heard the stuff leaks out of
seals, pumps and Ts.

On the plus side:

They used several other temperature sensors on the cell wall. They were
well calibrated and they all agree on the power levels.

The recovery rate is 88% as I recall. That's high. The whole thing is
insulated in a vacuum jacket (like a giant Dewar).

The calibration seems rock steady, and the calibration curve is linear.

These people have been dealing with this for a while so they have probably
answered all concerns. McKubre asked Kitamura to estimate the error as a
percent of input but Kitamura could not. Perhaps he misunderstood the
question. McKubre said it was a "good job" despite this.

U. Missouri intends to upload the slides from this conference, with
permission from the authors. I expect Kitamura will grant permission. This
is one you should look at.

- Jed

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