An official website of the United States government
Here's how you know
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.
Fig. 4. FE-SEM micrographs at different scales of balsa (a), (b) and (c) and birch (d), (e) and (f), respectively. The green arrows point at cell wall/middle lamella interfaces, the red arrows indicate the cell wall/lumen interfaces.