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SEM micrographs of: pristine (A) paper towel, (D) waxed paper, (G) Parafilm M®; SPEs onto (B) paper towel, (E) waxed paper, (H) Parafilm M®; CB modified SPEs onto (C) paper towel, (F) waxed paper, (I) Parafilm M®. Acceleration voltage: 5 keV, magnification 10 kx.
