Conduit capacities

The mesopores make some contribution to the adsorptive capacity, but thek main role is as conduits to provide access to the smaller micropores. Diffusion ia the mesopores may occur by several different mechanisms, as discussed below. The macropores make very Htde contribution to the adsorptive capacity, but they commonly provide a major contribution to the kinetics. Thek role is thus analogous to that of a super highway, aHowkig the adsorbate molecules to diffuse far kito a particle with a minimum of diffusional resistance. 

Electric Tracing An electric tracing system (see Fig. 10-178) consists of an electric heater placed against the pipe under the thermal insulation, the supply of electricity to the tracer, and any control or monitoring system that may be used (optional). The supply of electricity to the tracer usually consists of an electrical panel and electrical conduit or cable trays. Depending on the size or the tracing system and the capacity of the existing electrical system, an additional transformer may be required. 

If the laboratory lacks the right tool for a one-time highly specialized application, it would be impractical to buy it. There are tool rental firms which have just about anything that might be needed heavy duty Sanders, large capacity drills, power saws, electrical conduit benders—the list goes on and on. Best of all, the prices are quite reasonable. Such services should certainly be considered. 

Whereas solid microneedle arrays present the opportunity to create conduits through the restrictive skin barrier layer, the application of the formulation into the channel through drycoating the microneedle array or coadministration of a solution, suspension, emulsion, or gel containing the medicament generally relies on passive delivery mechanisms. The capacity to microfabricate hollow microneedles, however, allows a controlled quantity of the medicament to be actively delivered from the tip of the inserted microneedle at a defined rate. In addition, hollow microneedles provide the opportunity to not only deliver substances but also to withdraw material from the skin for analysis, monitoring, and responsive purposes. 

The thickness of the aerated zone and the nature of its soil and rocks have to be established in terms of the lithologies, prevalence of conduit flow or porous flow, and absorption capacity. 

In a large-scale distribution system, the pipelines provide a large volume continent-spanning storage reservoir in addition to their primary function as a conduit. In other applications, where modest capacity is required and cost is not a major consideration, gas can be stored in high-pressure bottles as is done with welding gas. 

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