My final report on the pressure is now available at
http://tinyurl.com/pdrd224
It includes corrections for thermal expansion and the van der Waals
effect. Your comments and suggestions will be welcome as always.
AlanG
On 2/20/2015 8:28 AM, Bob Higgins wrote:
Yes Bob, Thanks.
The effect due to thermal expansion has been evaluated by Alan
Goldwater to be a fraction of a percent. This pales in comparison to
the ~40% effect of the 2-volume 2-temperature calculation, the ~12%
effect of van der Walls vs. ideal gas, and the uncertainties in the
actual mass of LiAlH4. But, it should be a part of the calculation.
Another effect that could be at least as large is the mechanical
expansion of the alumina tube under the forces of the high pressure.
Thermal expansion increases the size of both the displacement rod and
the tube, but mechanical strain would only increase the tube diameter,
causing a bigger change in the dead volume.
Bob Higgins
