Perpendicular motion

Of course, for time t = rtube the perpendicular displacement is of the order of D and, hence, the tube constraint is strongly felt. For t > rtube the perpendicular motions are essentially equilibrated and the dynamics is determined by individual motions along the tube ... 

McConnell, H. M. Coupling between lateral and perpendicular motion in biological membranes. In "Functional Linkage in Biomolecular Systems" F. 0. Schmitt, D. M. Crothers, D. M. Schneider, Eds. Raven Press New York, 1975 pp. 123-131. 

All the sand exterior to the inverted cone had a component of perpendicular motion which appeared to be downward for all the sand exterior to the 45-deg lines drawn downward and outward from the edge of the plate, and upward for the sand exterior to these lines. 

Figure 3. Energy changes of PdH2 through the shifts from a linear head-on structure to a side-on (near C2v) geometry. To the right another sector of the three dimensional PdH2 potential energy surface, related to perpendicular motions of the Pd and the H moieties, is given.

Fig. 13D Motion of the liquid at the surface of an RDE. (o) tangential motion in the plane of the electrode, (b) perpendicular motion towards the electrode.

The translational motion is easily analysed. The motion of the polymer parallel to the tube axis, which is nearly parallel to u, is not hindered by the tube, so that the parallel component will be nearly equal to the diffusion constant in dilute solution Z> o-t On the other hand, the perpendicular motion is limited to within the distance a, so that the perpendicular component can be regarded as zero provided the small-scale motion of order a is neglected. Thus... 

The perpendicular motion of the two adjoining grains creates a stress concentration at the grain boundaries which must be relaxed in order for the deformation to proceed. This is equivalent to a nonconservative motion, and it is associated with the diffusional fluxes of the components to/from or along the interfaces, or to the dislocation motion, these being the main accommodation processes and the ratecontrolling process associated with GBS. 

Charged particles move quite differently in a magnetized plasma than in a not magnetized medium. This is because they can only move freely along the field lines of the magnetic field. In the perpendicular direction, they gyrate around the field lines and no net perpendicular motion is present in zero order. Their motion can be described as follows. 

The other possible motion under the topological constraints is that the blob moves along the confining tube surrounding it without large perpendicular motion. The movement is similar to that of snakes or earthworms, and is hence called reptation [25] (Figure 2.24). 

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