Diffusion oxygen transport

Slime is a network of secreted strands (extracellular polymers) intermixed with bacteria, water, gases, and extraneous matter. Slime layers occlude surfaces—the biological mat tends to form on and stick to surfaces. Surface shielding is further accelerated by the gathering of dirt, silt, sand, and other materials into the layer. Slime layers produce a stagnant zone next to surfaces that retards convective oxygen transport and increases diffusion distances. These properties naturally promote oxygen concentration cell formation. 

We would like to point out that an order parameter indicates the static property of the lipid bilayer, whereas the rotational motion, the oxygen transport parameter (Section 4.1), and the chain bending (Section 4.4) characterize membrane dynamics (membrane fluidity) that report on rotational diffusion of alkyl chains, translational diffusion of oxygen molecules, and frequency of alkyl chain bending, respectively. The EPR spin-labeling approach also makes it possible to monitor another bulk property of lipid bilayer membranes, namely local membrane hydrophobicity. 

The nature of oxygen transport within minerals in the presence of hydrothermal water and the role of diffusion. Chem. Geol. 53, 197-206. 

A typical PEFC, shown schematically in Fig. 1, consists of the anode and cathode compartments, separated by a proton conducting polymeric membrane. The anode and cathode sides each comprises of gas channel, gas diffusion layer (GDL) and catalyst layer (CL). Despite tremendous recent progress in enhancing the overall cell performance, a pivotal performance/durability limitation in PEFCs centers on liquid water transport and resulting flooding in the constituent components.1,2 Liquid water blocks the porous pathways in the CL and GDL thus causing hindered oxygen transport to the... 

Figure 11.1 Schematic examples of passive diffusion, facilitated transport and coupled transport. The facilitated transport example shows permeation of oxygen across a membrane using hemoglobin as the carrier agent. The coupled transport example shows permeation of copper and hydrogen ions across a membrane using a reactive oxime as the carrier agent...

Merchuk et al. [276] investigated the dynamics of oxygen electrodes when analyzing mass transfer, and they reported whether and when an instantaneous response occurs. A semiempirical description of diffusion coefficients was provided by Ju and Ho [198]. Bacillus subtilis cultures change the product concentration ratio between acetoin and butanediol rapidly in the range of p02 =80-90 ppb [286]. This fact could be used for the characterization of the oxygen transport capabilities of bioreactors. 

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