Thursday, 16 August 2001,  11:00 am 

Link Building Seminar Room

Dr David Williams
Dept. of Applied Mathematics

Particle Interactions in Biology and Soft Matter:
Why Onsager and Landau are wrong

ABSTRACT:

Colloid "science" should underly a great many important systems – from biology to minerals extraction. However, it has not contributed as it should.
The reason is that the theory which underlies much of colloid science is inadequate, and in many cases incorrect. In particular, ubiquitous specific ion effects are not accounted for by traditional theories, and the traditional theories have almost no predictive value.
In this talk I will outline the defects of two current theories. These are
(i) The Onsager-Samaris theory of the surface tension of salt solutions
(ii) The Deryaguin-Landau-Verwey-Overbeek (DLVO) theory of colloidal interactions.
It will be shown how the current theories fail for biological systems and how these theories can be corrected by proper inclusion of all the forces acting on the particles.
Ref: Bostrom, Williams, Ninham: Langmuir (in press).
Bostrom, Williams, Ninham: PRL (to appear)