Rapid transport

The energetics and kinetics of film formation appear to be especially important when two or more solutes are present, since now the matter of monolayer penetration or complex formation enters the picture (see Section IV-7). Schul-man and co-workers [77, 78], in particular, noted that especially stable emulsions result when the adsorbed film of surfactant material forms strong penetration complexes with a species present in the oil phase. The stabilizing effect of such mixed films may lie in their slow desorption or elevated viscosity. The dynamic effects of surfactant transport have been investigated by Shah and coworkers [22] who show the correlation between micellar lifetime and droplet size. More stable micelles are unable to rapidly transport surfactant from the bulk to the surface, and hence they support emulsions containing larger droplets. 

If a compact film growing at a parabolic rate breaks down in some way, which results in a non-protective oxide layer, then the rate of reaction dramatically increases to one which is linear. This combination of parabolic and linear oxidation can be tenned paralinear oxidation. If a non-protective, e.g. porous oxide, is fonned from the start of oxidation, then the rate of oxidation will again be linear, as rapid transport of oxygen tlirough the porous oxide layer to the metal surface occurs. Figure C2.8.7 shows the various growth laws. Parabolic behaviour is desirable whereas linear or breakaway oxidation is often catastrophic for high-temperature materials. 

That is, the H-bonded network provides a natural route for rapid transport. This phenomenon of proton jumping thus occurs with little actual movement of the water molecules themselves. Ice has an electrical conductivity close to that of water because such proton jumps also readily occur even when the water molecules are fixed in a crystal lattice. Such conduction of protons via H-bonded networks has been offered as an explanation for a number of rapid proton transfers of biological significance. 

Forced convection can be achieved in a variety of ways, e.g. by agitating the solution (stirring mechanically, sparging with gas bubbles, ultrasonic radiation, etc.) or by moving or rotating the metal electrode, and this will result in more rapid transport of the reacting species to the electrode than when the solution is unagitated. 

Figure 12-14. The creatine phosphate shuttle of heart and skeletal muscle. The shuttle allows rapid transport of high-energy phosphate from the mitochondrial matrix into the cytosol. CKg, creatine kinase concerned with large requirements for ATP, eg, muscular contraction CIC, creatine kinase for maintaining equilibrium between creatine and creatine phosphate and ATP/ADP CKg, creatine kinase coupling glycolysis to creatine phosphate synthesis CK, , mitochondrial creatine kinase mediating creatine phosphate production from ATP formed in oxidative phosphorylation P, pore protein in outer mitochondrial membrane.

Hall PS, Kincaid C (2001) Diapiric Flow at Subduction Zones A Reeipe for Rapid Transport. Science 292 2472-2475... 

When intestinal peristalsis and clearance are intact, the bacteria are rapidly transported aborally, and in the mid jejunum bacterial counts are in general low (normal) despite dense gastric colonization. Considerable evidence indicates that bacteria recovered from small bowel under such conditions are transient rather than resident. 

Recently, the importance of large particle formation and their subsequent rapid transport to abyssal depths of the oceans have been invoked as a mechanism to explain the distribution of several oceanic variables [60]. These studies have shown that there exists a direct transport path between sea surface and sea floor and that the sea floor can no longer be considered remote from the surface. This transport path may become significant for... 

Vessel element of Perforated cell with Rapid transport of water... 

Rapid transportation from sampling sites to laboratory... 

It is the large scale eddies that are responsible for the very rapid transport of momentum, energy and mass across the whole flow field in turbulent flow, while the smallest eddies and their destruction by viscosity are responsible for the uniformity of properties on the fine scale. Although it is the fluctuations in the flow that promote these high transfer rates, it is... 

R. E. Pagano and R. G. Sleight, Defining rapid transport in animal cells, Science 229, 1051-1057 (1985). 

Vermaelen KY. Carro-Muino I. Lambrecht BN. Pauwels RA Specific migratory dendritic cells rapidly transport antigen from the airways to the thoracic lymph nodes. J Exp Med 2001 193 51-60. 

Molecular size. For hydrophilic substances, as molecular weight and molecular size and radius increase, permeability typically diminishes. Small molecular weight perme-ants (MW < 100 Da) are rapidly transported through the buccal mucosa. 

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