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.
Variation of the subharmonic threshold of a Sonazoid microbubble with excitation frequency as predicted by the constant elasticity viscoelastic model. Inset: Variation of the effective surface tension with instantaneous radius for the same contrast agent.
