Confocal microscopy of colloidal dispersions in shear flow using a counter-rotating cone–plate shear cell

Autor:	Didi Derks, Hans Wisman, Arnout Imhof, Alfons van Blaaderen
Přispěvatelé:	Soft Condensed Matter and Biophysics, Universiteit Utrecht, Dep Natuurkunde
Rok vydání:	2004
Předmět:	Materials science business.industry Velocity gradient Condensed Matter Physics Physics::Fluid Dynamics Condensed Matter::Soft Condensed Matter Shear rate Colloid Optics Shear (geology) General Materials Science SPHERES Composite material business Shear flow Shear band Refractive index
Zdroj:	Journal of Physics: Condensed Matter. 16:S3917-S3927
ISSN:	1361-648X 0953-8984
DOI:	10.1088/0953-8984/16/38/010
Popis:	We report on novel possibilities for studying colloidal suspensions in a steady shear field in real space. Fluorescence confocal microscopy is combined with the use of a counter-rotating cone?plate shear cell. This allows imaging of individual particles in the bulk of a sheared suspension in a stationary plane. Moreover, this plane of zero velocity can be moved in the velocity gradient direction while keeping the shear rate constant. The colloidal system under study consists of rhodamine labelled PMMA spheres in a nearly density and refractive index matched mixture of cyclohexylbromide and cis-decalin. We show measured flow profiles in both the fluid and the crystalline phase and find indications for shear banding in the case of a sheared crystal. Furthermore, we show that, thanks to the counter-rotating principle of the cone?plate shear cell, a layer of particles in the bulk of a sheared crystalline suspension can be imaged for a prolonged time, with the result that their positions can be tracked.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::b9609b7fb7d3441050f438a271ea8a3f https://doi.org/10.1088/0953-8984/16/38/010 Zobrazit plný text záznamu