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This run features an aqueous solution that is approximately 15.5 wt.% Na2SO4. Initially, the pressure was about 176 MPa. 11/06/30 11:08:43: The system starts all liquid at about 303 K and 176 MPa. Upon cooling, the liquid undergoes thermal contraction and the volume and pressure decrease slightly. 11/06/30 13:27:50: After supercooling to 280 K, mirabilite crystals quickly grow and fill in from the bottom. There was some condensation on the optics lenses, so the image is dimmer than normal. Increasing the bulb brightness helps. 11/06/30 15:27:50: A sudden increase in volume and pressure indicate the formation of Ice Ih, which is visible in the window two frames later. 11/07/01 16:41:50: Slow warming leads to significant melting around 250 K, much cooler than the expected eutectic temperature of 254 K. The transition is reversible. 11/07/02 10:07:50: Further warming about 259 K starts dissolving the remaining mirabilite until the liquidus temperature is reached. 11/07/02 21:27:50: Once all the solids are dissolved, the fluid undergoes thermal expansion as the sample warms further.
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