Resistazone Stream Counters

When interpreting the data from a stream method, one must be concerned about the fact that the physical properties of the interrogation zone may not be isotropic. For example, in the literature on the Coulter Counter, a well-known resistazone stream counter, it was assumed for a long time that the signal generated in the instrument was independent of the location of the fineparticle within the zone. More recent work, however, has established that, if the fineparticle is close to the wall of the cylinder of... 

Figure 6.3. Hydrodynamic focusing is used in the Coulter Counter TF resistazone stream counter to ensure that fineparticles travel down the centre of the interrogation zone, a) Hydro-dynamic focusing as used in the Telefimken system, b) Size distribution of whole blood by the Coultet TF system, c) Size distribution of standard 2.02 mm latex spheres.

Figure 7.11. Comparison of results obtained by Palmer, using laser diffraction and resistazone stream counter for fineparticles of various shapes, a) Results for spherical latex fineparticles. b) Results for spherical diamond dust with some cubic fineparticles. c) Results for plate-like fineparticles. d) Results for rod-shaped particles. (Micrographs and data used by permission of American Laboratory and, J. Cowley, T. Palmer and P. J. Logiudice [4l].)...

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