Coalescent migration

Triacylglycerol has no polar interaction with the membrane phospholipids and is either released into the cytosol as tiny lipid droplets or into the lumen of the ER. In fat cells, oil droplets in the cytosol coalesce, migrate toward and fuse with the large central oil droplets. In the liver and intestine, triacylglycerol is packaged into lipoproteins (VLDL and chylomicrons, respectively), which then are secreted into the circulation (see Fig. 13-11). 

The second class of atomic manipulations, the perpendicular processes, involves transfer of an adsorbate atom or molecule from the STM tip to the surface or vice versa. The tip is moved toward the surface until the adsorption potential wells on the tip and the surface coalesce, with the result that the adsorbate, which was previously bound either to the tip or the surface, may now be considered to be bound to both. For successful transfer, one of the adsorbate bonds (either with the tip or with the surface, depending on the desired direction of transfer) must be broken. The fate of the adsorbate depends on the nature of its interaction with the tip and the surface, and the materials of the tip and surface. Directional adatom transfer is possible with the apphcation of suitable junction biases. Also, thermally-activated field evaporation of positive or negative ions over the Schottky barrier formed by lowering the potential energy outside a conductor (either the surface or the tip) by the apphcation of an electric field is possible. FIectromigration, the migration of minority elements (ie, impurities, defects) through the bulk soHd under the influence of current flow, is another process by which an atom may be moved between the surface and the tip of an STM. 

Pt particle coalescence is due to migration. This mechanism is supported by observations that, upon cycling, Pt particle size distributions are shifted toward larger sizes, indicating that smaller particles are more mobile. It is noted that this observation could also result from the effects of Ostwald ripening. 

The collision of the broken wet segments during spheronization can result in two effects deformation and coalescence. The migration of moisture or soluble binders from the core to the surface of the pellets improves surface... 

Decause modem demulsifiers can readily migrate through oil due to their high surface activity, and can effectively promote coalescence, they perform very well with a minimum of agitation Earlier demulsifiers required significantly more agitation to produce an acceptable performance. 

Parallel-plate interceptor. The first form of plate coalescer was the parallel-plate interceptor (PPI). This involved installing a series of plates parallel to the longitudinal axis of an API separator (a horizontal, rectangular cross-section skimmer). When viewed perpendicular to the axis of flow, the plates form a "V so that the oil sheet migrates up the underside of the coalescing plate and to the sides Sediments migrate toward the middle and down to the bottom of the separator where they are removed. 

A skim pile is a type of disposal pile. As shown in Fig. 9, flow through a scries of baffle plates creates quiescent wines that reduce the distance which a given oil droplet must rise to be separated from the main flow. Once in the quiescent zone, there is ample time for coalescence and gravity separation. Larger droplets then migrate up the underside of the baffle to an oil collection system... 

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