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.
(Control: no oil, E1: 1 µL L−1, E2: 5 µL L−1, E3: 25 µL L−1.) Error bars represent the standard errors.
