Diameter image-shearing

Fig. 2.1 Methods of estimating d, the projected area diameter (a) image shearing method [after Heywood (H6)] (b) statistical intercept method [after Martin et al. (Ml)].

The image shearing diameter IS refers to an optical microscope technique in which two images of the same particle are obtained and displaced so that they are just touthing. The length of the displacement is the image shearing diameter of the particle. 

Determining fiiament diameter using a Watson image shearing eyepiece... 

The process leading to monodisperse emulsions was initially described by Mason and Bibette [ 1,24,26-28]. For that purpose, they first prepare a crude mother emulsion obtained by progressively incorporating oil into the surfactant-water phase. In a second step, they apply a simple and well-controlled shear to this crude emulsion that becomes monodisperse after no more than a few seconds. Figure 1 shows microscope images before and after application of a shear under the same conditions used by Mason and Bibette. The shear has the effect of reducing both the average diameter and the distribution width of the mother emulsion. 

Fig. 7 Reprinted with permission from [111], copyright (2004), Institute of Physics Publishing. Confocal images (yz, 75p.mx56gm, 512x512 pixels-) of a colloidal fluid at various shear conditions taken in a counter-rotating cone-plate shear cell [111] see Sect. 2.3. The applied shear rates are 1.67,3.36 and 8.39 s (fop to bottom)-, the ratios ofthe applied cone to plate rotation speeds are 84, 129 and 175 (left to right). Graphs (a) and (b) show displacement profiles, y(z). measured from these images via cross-correlation of scanned lines. The appropriate profile is overlaid on each image (white curves). The velocity profiles (dy/dz) calculated from these displacement profiles are shown in the graphs (c) and (d). The particle diameter is 1.50 pm...

Fig. 14 Reprinted with permission from [111], copyright (2004), Institute of Physics Publishing, (a) Superposition of particle tracks in the zero-velocity plane plus one adjacent plane in a sheared colloidal crystal, showing zig-zag motion. The image size is 18.75 pm x 18.75 pm (256 x 256 pixels). The colloids have a diameter of 1.50 pm. (b) Measured shear rate vs applied shear rate for the colloidal crystal (points), the continuous line shows equahty of these two rates...

Fig. 15 Reprinted with permission from [103], copyright 2004 by the American Physical Society. Structure of a sheared suspension (diameter 1.42 pm) with strain amplitude /o = 0.38, frequency / = 30Hz and

In a wide-gap Couette rheometer, migration of spheres was followed by nuclear magnetic resonance imaging [Abbott et al, 1991]. Migration to the low shear rate region was found to be determined by the total strain, proportional to the shear rate and square of the particle diameter, but independent of the (Newtonian) viscosity of the matrix liquid. More recently, similar studies were undertaken for suspensions of rods with... 

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