Particle-surface adhesive forces and their role in resuspension phenomena

Benefitting from complementary expertise in colloid science and aerosols at the universities of
Bath and Bristol, the student will apply a variety of techniques to explore the physicochemical
factors controlling resuspension of primary particles from surfaces. The project will progress
through stepwise increases in experimental complexity coupled with mechanistic model
development and validation, exploring different types and morphology of surface, both substrate
and particle.

Specific objectives will include:
1. Develop a range of model surfaces with controlled morphology, hydrophobicity and
surface energy, using a combination of techniques such as 3D printing and thin film
coating.
2. Measure adhesive force distributions between these surfaces and salt and sugar particles
of controlled morphology using colloidal probe atomic force microscopy (AFM).
3. Investigate the effect of environmental humidity on these adhesive force distributions.
4. Implement the measured adhesive force distributions into the mechanistic Adaptive Biasi
Rock-and-Roll Model.
5. Assess a subset of identified surfaces and particles in the resuspension wind tunnel. This
will validate approaches and relate the single particle interactions investigated by AFM to
the complexities of wind tunnel resuspension.
If initial work with model surfaces and particles is successful, the approach will be extended to
include a range of realistic surfaces and particles of interest (e.g. concrete, bacteriological media).