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.
(a) Images of CDs and SFCDs in water. CDs are highly immiscible in water. Bare CDs get slightly dispersed on vigorous stirring, while SFCDs settle at the bottom of the vial; Emission spectra for carbon dots immersed in water for (b) bare CDs λex = 350 nm (c), SFCDs λex = 250 nm, and (d) SFCDs λex = 350 nm.
