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Preliminary Data for Sodium Sulfate Solutions

We made numerous runs at concentrations of 15.5 wt%, which is well above the eutectic composition. Here are some annotated examples, along with brief summaries of each run.

Initial
Pressure
Label Summary Description
50 MPa 15NaS_50MPa_19Oct05 A straightforward run at a nominal pressure of 50 MPa. The solid phase includes Ice Ih.
250 MPa 15NaS_250MPa_03Oct05 A straightforward run at a nominal pressure of 250 MPa in the high-pressure Ice regime.
0.4 MPa 15NaS_0.4MPa_19Sep05 A run at low pressure.
50 MPa 15NaS_050MPa_12Jan12 A longer, more complex, run at 50 MPa.
75 MPa 15NaS_075MPa_07Aug11 A longer run with multiple passes through the eutectic transition.
100 MPa 15NaS_100MPa_11Oct05 A run at 100 MPa
150 MPa 15NaS_150MPa_20Aug08 A run at 150 MPa. Condensation on the lenses obscured the view during most of the run.
150 MPa 15NaS_150MPa_14Jul11 A run at 150 MPa with an unexpectedly low temperature transition.
175 MPa 15NaS_175MPa_30Jun11 A run at 175 MPa with an unexpectedly low temperature transition.
230 MPa 15NaS_230MPa_08Sep11 A run at pressure 230 MPa. This run initially freezes to a low-density Ice Ih phase, but after a slight increase in pressure, switches to a high-density ice phase.
230 MPa 15NaS_230MPa_23Sep11 A run starting at pressure 230 MPa. This run appears to include both low-density and high-density ice phases. The pressure was slowly increased during the run until the ice phase changed.
250 MPa 15NaS_250MPa_08Feb10 A run at pressure 250 MPa in the Ice III regime.
250 MPa 15NaS_250MPa_14May10 A run at pressure 250 MPa in the Ice III regime.
250 MPa 15NaS_250MPa_17Feb06 A run at pressure 250 MPa in the Ice III regime.
250 MPa 15NaS_250MPa_17Oct11 A run starting at a pressure of 250 MPa. The pressure was gradually increased to 270 MPa to see how stable the initial ice phase was, and then gradually decreased to 230 MPa,.
250 MPa 15NaS_250MPa_26Oct11 A run starting at a pressure of 250 MPa. The pressure was gradually increased to around 310 MPa.
260 MPa 15NaS_260MPa_17Nov11 A run starting at a pressure of 260 MPa. The pressure was gradually increased to around 320 MPa.
265 MPa 15NaS_265MPa_31Jul10 A run starting at a pressure of 265 MPa. The pressure was gradually increased to around 320 MPa.
280 MPa 15NaS_280MPa_17Feb10 A run at a pressure of 280 MPa.
280 MPa 15NaS_280MPa_24May10 A simple run at pressure 280 MPa.
300 MPa 15NaS_300MPa_01Jun10 A simple run at pressure 300 MPa
300 MPa 15NaS_300MPa_07Jun10 A long run starting at a pressure of 300 MPa, but with the pressure systematically lowered to 220 MPa and then raised back up to 260 MPa to monitor various transitions.
300 MPa 15NaS_300MPa_26Sep05 A run at pressure 300 MPa
320 MPa 15NaS_320MPa_04Dec11 A run at pressure 320 MPa
320 MPa 15NaS_320MPa_24Feb10 A run at pressure 320 MPa
325 MPa 15NaS_325MPa_07Jul10 A run at pressure 325 MPa
325 MPa 15NaS_325MPa_15Jul10 A run at pressure 325 MPa
325 MPa 15NaS_325MPa_28Feb06 A run at pressure 325 MPa
350 MPa 15NaS_350MPa_03Mar10 A run at pressure 350 MPa
350 MPa 15NaS_350MPa_19Dec11 A run at pressure 350 MPa
350 MPa 15NaS_350MPa_23Jun10 A run at pressure 350 MPa
385 MPa 15NaS_385MPa_09Mar10 A run at pressure 385 MPa

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