Il Nuovo Cimento D

, Volume 16, Issue 8, pp 1091–1101 | Cite as

Depolarized light scattering study of equilibrium sedimentation profiles of colloidal dispersions

  • V. Degiorgio
  • R. Piazza
  • T. Bellini
Article
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Summary

Equilibrium sedimentation profiles of concentrated suspensions of charged optically anisotropic colloids are accurately determined by performing depolarized light scattering measurements. From the data we derive the osmotic pressure πvs. the particle volume fraction Φ. The π(Φ) values obtained with strongly screened colloids are in excellent agreement with the predicted hard-sphere equation of state. The data suggest that, besides gravitation, there is an additional force acting on the particles, probably due to the build-up of an electrostatic sedimentation potential.

PACS 82.70.Dd

Colloids 

PACS 78.35

Brillouin and Rayleigh scattering 

PACS 64.10

General theory of equations of state and phase equilibria 

PACS 01.30.Cc

Conference proceedings 
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Copyright information

© Società Italiana di Fisica 1994

Authors and Affiliations

  • V. Degiorgio
    • 1
  • R. Piazza
    • 1
  • T. Bellini
    • 1
  1. 1.Dipartimento di Elettronica dell'UniversitàPaviaItaly

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