Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
SEM images displaying the cross sections of the following membranes: (a) cylindrical channels in PI; (b) conical channels in PI; (c) cigar-shaped channels in PET, (d) cylindrical channels with rhombohedral cross section in mica. (a,b) Adapted with permission from [26] – Copyright 1996 Elsevier; (c) adapted with permission from [42] – Copyright 2007 IOP Publishing Ltd; (d) adapted with permission from [43] – Copyright 2012 American Physical Society.
