Particle video microscopy,

Particles can be manipulated in suspension using strongly focused laser beams ( optical tweezers ) [25] or magnetic fields [26] and by collecting statistics on tire particle movements using video microscopy, infonnation on the particle interactions can be obtained. 

In addition to the patent literature available on the production of BR in the gas-phase there is some scientific literature which mainly refers to the modeling of reaction kinetics. Details on the experimental procedure for the determination of the macroscopic kinetics of the Nd-mediated gas-phase polymerization of BD in a stirred-tank reactor are reported [568,569]. Special emphasis is given to video microscopy of individual supported catalyst particles, individual particle growth and particle size distribution (PSD). These studies reveal that individual particles differ in polymerization activity [536,537,570,571]. Reactor performance and PSD are modeled on the... 

Fig. 27 Video microscopy kinetics polymerization rate-time profiles for several particles...

V.A. Tolpekin, M.H.G. Duits, D.V.D. Ende, J. Mellema, Aggregation and breakup of colloidal particle aggregates in shear flow, studied with video microscopy. Langmuir 20(7), 2614-2627 (2004). doi 10.1021/la0357581... 

Bigioni et al. [616] have used video microscopy to study the process of assembly of Au nanocrystals into extended two-dimensional arrays. They suggest that the morphology of the drop-deposited nanocrystal films is controlled by evaporation kinetics and particle interactions with the liquid-air interface. In the presence of an attractive particle-interface interaction, rapid early-stage evaporation dynamically produces a two-dimensional solution of nanocrystals at the liquid air interface, from which nanocrystal islands nucleate and grow upon further evaporation. 

A. Kasper, E. Bartsch, and H. Sillescu. Self-diffusion in concentrated colloid suspensions studied by digital video microscopy of core-shell tracer particles. Langmuir, 14 (1998), 5004-5010. 

The selection of the optimum bead size is a compromise. On the one hand, the particles should be as small as possible to minimize force due to Brownian motion. On the other hand, optical video microscopy is used for position tracking and the magnetic force scales with the particle volume (Eq. (3.36)). Typical head diameters are 0.5-5 pm. 

The position of the particle in the x-y-direction is also determined by video microscopy. A tracking algorithm, usually coded by last Fourier transform-based couelation techniques, allows for a resolution of 1 nm Hz for high frequencies, where the miao-... 

Synergism caused by the addition of Group C particles was found from both SEM microscopy and video macroscopy (Xia and Kwauk, 1985) to be associated with adhesion of these line particles on the coarse particle. Nevertheless, more appropriate analytical, or even theoretical, ground needs to be found to account for the initial rise and later fall in the value of the dimensionless time 0 as the mass fraction of fines increases from zero to unity. 

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