Particle tracking rotational motion

Parker, D., Dijkstra, A., Martin,T., and Seville, J. (1997), Positron emission particle tracking studies of spherical particle motion in rotating drums, Chem. Eng. Sci., 52, 2011-2022. 

D. J. Parker, A. E. Dijkstra, T. W. Martin, and J. P. K. Seville. "Positron emission particle tracking studies of spherical particle motion in rotating dmms," Chem. Eng. Set, 52(13), 2011-2022, 1997. 

Particle tracking can also be used to monitor particle orientation. Cheng and Mason studied rotational motion of micron-size a-eicosane microdiscs in 900 kDa polyethylene oxide(92). Hill and Soane examined the rotation of collagen molecules in aqueous 4 MDa polyethylene oxide using the electro-optic Kerr effect(93). 

Here we examine the literature on diffusion of probes through polymer solutions. Nearly 200 probe size polymer molecular weight combinations have been examined at a range of polymer concentrations. There is a solid but not extremely extensive body of work on the temperature dependence of probe diffusion in polymer solutions. A half-dozen studies of probe rotational motion and more than a dozen reports based on particle tracking are noted, along with a half-dozen sets of true microrheological measurements, in which mesoscopic objects perform driven motion in polymer solutions. 

Features of PEPT of particular benefit to engineering studies include the fact that the actual particles of interest may be used as tracers, rather than dissimilar materials of unknown behaviour, and that y-rays are sufficiently penetrating that location is unimpaired by the presence of metal walls, for example. In recent developments, the minimum size of particles which can be tracked has been reduced to approximately 60 pm. It is now possible to track multiple particles, to determine particle rotation and to track motion within real industrial equipment by use of a mobile modular positron camera. These developments are described later. 

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