1.
Phys Rev Lett
; 90(12): 126104, 2003 Mar 28.
Artigo
em Inglês
| MEDLINE
| ID: mdl-12688889
RESUMO
We have measured the shear viscosity in the liquid phase of several Langmuir monolayers with an accuracy better than 30%. The method is based on the optical monitoring of the Brownian diffusion of submicron latex spheres floating at the air-water interface. The values are between 1 and 11x10(-10) N s m(-1), which is 10 to 100 times lower than previous data on similar systems. For N-palmitoyl-6-n-penicillanic acid and L-alpha-dipalmitoylphosphatidylcholine, the variation of the shear viscosity with surface density agrees with a classical free area model, whereas for pentadecanoic acid we observe a compensation effect.