Paraphrasing Rayleigh, if the thermal expansion occurs while the pressure is high and the thermal contraction
while the pressure is low, the gas does net work on the wave surrounding it during every cycle of the oscillation.
The solidification of plastics typically results in a reduction in their volume (shrinkage) followed by further thermal contraction
as temperature decreases below their solidification temperature.
In addition, the difference between thermal contraction
coefficient of the Al-Cu-Fe-Mn compounds and the matrix resulted in an interface with a high density of dislocations.
The TSB deemed that the fracture was caused by incremental stresses to the pipeline, which may have been the result of weakened soil support from maintenance activities over the years; record low temperatures that winter; recent work near the valve site that may have driven frost deeper into the ground; and thermal contraction
as the pipeline cooled during a 20-day shutdown.
The other would be the methods used to join pipe, including early electric arc welds, acetylene welds, couplings and threaded collars, all of which could have strength or ductility properties that limit tolerance for loadings induced by frost heave or thermal contraction
The thermal stresses and birefringence are generated due to the interactions between nonhomogeneous thermal contraction
and changes in the polymer viscoelastic and optical properties during cooling.
When poured into a permanent mold, however, A206 has a tendency for hot tearing, which is caused by thermal contraction
in the late stages of solidification.
Smaller polygon-shaped bodies are found elsewhere on Mars, but these are best explained by thermal contraction
processes similar to those in terrestrial permafrost environments and not likely to form larger polygons.
Because this shift is in the opposite direction from what would occur with thermal contraction
of the tube assembly, I attribute it to thermal changes within the objective--something I've encountered with other triplets as well.
The contraction observed after the light source was removed may be attributed to progressive cross-linking reactions that occur after photoactivation was concluded (post-cure), and to thermal contraction
due to loss of radiant heat.
Recent research on these so-called negative thermal expansion (NTE) materials has led to the discovery of alloys exhibiting unexpectedly large thermal contraction
would not only drop its surface below sea level, but the density increase might also sink it altogether into the deep mantle.