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Old 08-30-2007, 09:59 PM   #21
Beest
Adapt and Survive
 
Join Date: Jan 2007
Location: Ann Arbor, Mi
Posts: 957
I usually try and do this at least once each winter, personally I'm going for catching a falling flake, and imaging it without any prep. All that freezing with liquid nitrogen and bombarding with ions might change the structure.
Then again I haven't been successful yet.


Quote:
Originally Posted by Scriveyn View Post
I had been wondering how they did it, beacause electron microscopes can only image objects whose surface is electrically conductive. -
Modern (for at least the last ten years) electron microscopes can image non conducting objects by using a low gas pressure in the chamber, incoming beam ionizes the gas around the beam providing a conducting path to dispel charge.

Low beam currents, and accelerating voltages, also help reduce sample charging in the Field emission type SEMs.

I bet you're sorry you asked now
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