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This run features an aqueous solution that is approximately 15.5 wt.% Na2SO4. Initially, the pressure was about 54 MPa. 12/01/12 12:00:12: The run started around 290 K. There were some mirabilite crystals still left in the bottom of the cell from the previous run. As the system cooled, those mirabilite crystals grew into the field of view. 12/01/12 15:20:12: At T = 262, much of the remaining liquid starts freezing quickly. The connecting tubing is at least partially frozen at this point, so the pressure and volume readings likely do not fully reflect the conditions inside the cell. The pressure is likely much higher. Next, the system will be warmed up to eventually reach the eutectic temperature. At these higher pressures, we see some early melting and softening of material. As the material softens in the connecting tubing, the pressure inside the cell lessens a bit. 12/01/16 17:30:12: At T = 267.13 we see rapid melting; the pressure and the voltage also drop quite quickly, indicating that the connecting tubing is sufficiently melted that the pressure and voltage readings are meangingful again. 12/01/16 20:10:12: Start cooling again to try to repeat that melting process. Again get rapid melting at the same temperature. 12/01/18 21:50:12: Cooling to slightly below 267 causes regrowth of the crystals at the top of the screen. 12/01/19 15:45:09: Start cycling temperature one more time. 12/01/23 07:40:09: Again get rapid melting at about the same temperature and pressure. 12/01/23 12:28:09: Continued warming starts us along the liquidus curve, but in this experiment we warmed too quickly to observe the liquidus transition carefully.
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