Are all fields created equal?
I’ve always wondered what the variability was in the pore statistics extracted from TEM images of different fields on the same membrane (SC 141). I took a series of ten images from random positions (corners, edges, center) and ran them through the pore processor. Here are the results:
(images taken at 100 kx)
| position | porosity | cutoff [nm] |
| 1 | 6.74% | 19.6 |
| 2 | 6.58% | 19.4 |
| 3 | 6.97% | 19.6 |
| 4 | 6.64% | 19.4 |
| 5 | 6.95% | 19.6 |
| 6 | 7.08% | 19.7 |
| 7 | 7.00% | 19.4 |
| 8 | 6.92% | 19.6 |
| 9 | 6.78% | 19.5 |
| 10 | 6.79% | 19.7 |
| avg | 6.85% | 19.55 |
| std dev | 0.16% | 0.12 |
I think it’s safe to say that statistics from one location on the membrane is representative of the entire film.