Figure 4.
High-performance Liquid Chromatography chromatograms of coumarin after heating at 200 °C. Phenol was used as the internal standard.
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.