Pinning effect

Agitator discs are available is several forms smooth, perforated, eccentric, and pinned. Effect of disc design has received limited study, but pinned discs are usually reserved for highly viscous materials. 

As shown in Fig. 1, chain sliding diffusion becomes difficult due to pinning effect within the interface between a nucleus and the melt. Since Jo is proportional to the topological diffusion constant D, D is related to ve from Eq. 62,... 

An electrical plug has three connections (or pins ) live , neutral and earth . The earth pin is necessary for safety considerations. The potential of the earth pin is the same as that of the ground, so there is no potential difference if we stand on the ground and accidentally touch the earth pin in a plug or electrical appliance. We will not be electrocuted. Conversely, the potentials of the other pins are different from that of the earth - in fact, we sometimes cite their potentials with respect to the earth pin, effectively delining the potential of the ground as being zero. 

A. Tanguy, M. Gounelle and S. Roux, From Individual to Collective Pinning Effect of Long-range Elastic Interactions, Phys. Rev., E58, 1577 (1998). 

A drastic decrease of photovoltage in UHV is obtained by introduction of surface states at the semiconductor surface. Particle bombardement of cleaved (0001) faces leads to preferential sputtering of the chalcogenide. The metal is reduced and new electronic bandgap states are formed at the surface. As a consequence a Fermi level pinning effect occurs which results in a smaller shift of EB due to halogen adsorption and decreased photovoltages and consequently an increased double layer potential drop (Fig. 4). 

Lower surface state densities will, of course, produce less of a Fermi level pinning effect. This will result in an increased sensitivity of Vbi to changes in A quantitative measure of the degree of ideality of a junction can be obtained by plotting changes in Vpi (or [Pg.4351]

As far as the orientation of the central block is concerned, a slower relaxation is also observed for the star as shown in Figure 12. At long times, the central block of the star remains more oriented than that of the linear chain. The differences are significant and cannot be explained by simple differences between length of chains and blocks. This effect must therefore be attributed to the "pinning" effect of the centre of the chain and subsequent suppression of the reptation motion. 

Magnetic flux pinning effect of impurities in copper oxide superconductors... 

Figure 8. TEM micrograph of Zr modified 2014 aluminum alloy torsion strained at 250 °C, 10 1 s 1 showing the grain boundary pinning effect of Al3Zr precipitates.

Experimental data presented here indicate that the wear behaviour of PTFE, as well as linear polythenes, is quite different from that expected on the basis of the simple thin film transfer mechanism described earlier. The results are unambiguous but at first sight difficult to explain. In the search for an explanation of the unusual wear behaviour shown by PTFE and linear polythenes, an analysis of the relative motions in "vertical" pin-to-disc configuration was carried out. There was a strong indication that this unusual wear behaviour of PTFE, HDPE and UHMPE arises from a pecularity in the pin-on-disc method (10). Since the fixed pin describes a circular path, the motion is complex. To a good approximation it may be considered to be comprised of a linear vector V, combined with a pin effectively rotating about its axis with an... 

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