About a year and a half ago, the person started getting interested in aerogel and bought some despite its expense. They received a pressure chamber from Ben of Applied Science and experimented with making carbon dioxide go supercritical. They observed the transition from solid to gas, noted a broken pressure gauge, and saw how silica beads behaved in the supercritical fluid. When the chamber was emptied, the beads behaved differently, confirming the presence of a supercritical fluid.
Here are the key facts extracted from the text:
1. The author became interested in aerogel about a year and a half ago.
2. The author obtained a small square of aerogel.
3. Supercritical fluids, specifically supercritical CO2, are commonly used in aerogel production.
4. The author contacted Ben from Applied Science for help with a pressure chamber.
5. Ben sent the author a pressure chamber for free.
6. The author attempted to make CO2 go supercritical multiple times.
7. The pressure gauge didn't work properly.
8. The author monitored temperature with a thermocouple.
9. The author successfully made CO2 go supercritical.
10. Liquid CO2 can be turned back into gas by cooling it.
11. Silica beads were placed in the supercritical CO2, and their behavior was observed.
12. The presence of supercritical CO2 prevented the beads from moving freely.
13. The author conducted tests to demonstrate the fluid-like behavior of supercritical CO2.
These facts provide an overview of the author's experiments and observations related to supercritical CO2 and aerogel.