[3dem] Powdered carbon fiber

[Terje Dokland]

We have a user in the materials science who is interested in looking  
at carbon fiber samples in the TEM. My understanding is the sample  
will be carbonized and powdered, then applied it to holey film before  
putting it in the microscope. They are interested in the pore sizes.  
Our F20 TEM is primarily used for cryo-EM of biological samples.  
Should I be concerned about contaminating the column? Carbon powder  
does not seem like something I want inside the column, but perhaps it  
should not be a concern? As long as the powder stays on the grid it  
should not be a problem, I suppose, but just sprinkling the powder on  
the grid does not seem to be such a good idea. Would there be a way  
to ensure that the sample does stick to the grid, such as washing or  
outgassing or pre-treating the grids?