Soft cylinder between

Consider the electrostatic interaction between two parallel dissimilar cylindrical soft particles 1 and 2. We denote by di and d2 the thicknesses of the surface charge layers of cylinders 1 and 2, respectively. Let the radius of the core of soft cylinder 1 be fli and that for soft cylinder 2 be U2- We imagine that each surface layer is uniformly charged. Let Z and N, respectively, be the valence and the density of fixed-charge layer of cylinder 1, and Z2 and N2 for cylinder 2. 

FIGURE 15.7 Interaction between two parallel soft cylinders 1 and 2 at separation H. Cylinders 1 and 2 are covered with surface charge layers of thicknesses di and d2, respectively. The core radii of cylinders 1 and 2 are ai and 2> respectively. 

The interaction force Pcy//(H) acting between two soft cylinders per unit length is given by P yz/iH) = —dVcy// H)ldH, which gives [9]... 

Cortex—The root cortex is a relatively soft tissue that occurs between the epidermis and the internal, vascular tissues. Functions primarily in storage and in movement of water into the vascular cylinder. 

Fig. 13.15), so as to resemble the surface of a latex particle. The two rubber cylinders, A and B, were mounted vertically, one above the other. The upper cylinder was held fixed during the experiment whereas the position of the lower cylinder could be moved up and down by a micrometer drive unit (D). Moving the cylinder A up towards B, after polymer had been adsorbed onto the poly(methyl methacrylate) surfaces, distorted the soft, elastic surfaces in the centi region, resulting in flat discs in the zone of interaction. The distance of separation between the surfaces was measured by multiple beam interferometry. The applied pressure caused an equilibrium contact area to be formed, the magnitude of which could also be determined interferometrically. The relationship between contact area and the equilibrium pressure was established by direct calibration. In this fashion, the equilibrium pressure could be measured for a given distance of separation. 

The cups are small plastic cylinders that are used to investigate the release of ammo acids from cortical structures m acute and chronic experiments. For acute experiments, Clark and Collins (1976) used a Perspex cup, 4 mm id, that was placed on the surface of the visual cortex. The junction between the brain and cup was sealed with soft white paraffin The cup contained 50 jjlL Ringer solution and was exchanged every 10 mm see Fig. 4) The ion composition of the solution could be changed to study effects on the release The ammo acids in the "exchanged" solution were determined and the temperature in the cup and the electrocorti-cogram of the surface in the cup were monitored. A bipolar platinum electrode was inserted 0.5 mm below the surface of the cortex either within or outside the cup for electrical stimulation During these experiments the animal was anesthetized... 

Figure 46 Chemical structures of PAA96-6-PS49 and PAEAi28-6-PS4o, and cartoon representation of the self-assembled spheres and cylinders and the hierarchical assembly between them. TEM images of spheres, cylinders, and cylinder-templated assembly of spheres. Reproduced with permission Zhang, K. Fang, H. Li, Z. etal. Soft Matter zm, 5(19), 3585-3589. ...

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