That Old-Fashioned Electron Microscopy
Yesterday I finished an SEM prep. Normally that would not be particularly remarkable, but it should be emphasised that I was the one that did the critical-point drying, and not the EM tech. This meant dealing with an amazingly old-school critical point dryer. The last one that I used, at UBC, had its own heater and various flow control systems; this one was just a cylinder with a water jacket and a window and three valves and two gauges. Hot and cold water was used as a temperature system, and gas flow was just a matter of fiddling with the valves. The window was the hardest part; because there was a risk of it blowing out, it was viewed through a mirror, which made the liquid level very hard to determine. I lost it several times, but I am fairly certain that my samples are all right, as I generally added too much liquid rather than too little. Of course, midway through, we started running out of carbon dioxide, which meant that the tech had to finish the job, but even still, it was a fun learning experience.