or making the Zente insole is complicated and costly and the result is less than optimum since the desired cushion effect is diminished by the presence of multiple plastic layers between the liquid and the foot.

1. Technical Field
The present invention relates generally to reactors, and more particularly to fabricating substrates that may be used in reactors.
2. Description of Related Art
Many reactions involving fluids (e.g., gases, liquids, and the like) use reactors. Many reactions are temperature dependent, and so a reactor (or zone within a reactor) may be required to have certain chemical, mechanical, thermal, and other properties at a temperature of interest to the reaction. Some reactions are performed at high temperatures (e.g., above 100 C, above 400 C, above 800 C, above 1100 C, or even above 1500 C), and so may require reactors having appropriate properties at the temperature of interest. Some reactions entail a heterogeneous reaction (e.g., involving a fluid and a surface).
Abatement of exhaust streams (e.g., from engines, turbines, power plants, refineries, chemical reactions, solar panel manufacturing, electronics fabrication, and the like) may include heterogeneous reactions. In some cases, the period of time during which a fluid interacts with a surface may affect the efficacy of a reaction. Certain reactions may benefit from increased contact times between a fluid and a substrate. Certain reactions may benefit from reduced contact times between a fluid and a substrate.
Some reactions proceed at practical rates at high temperatures. In some cases, an exhaust stream may provide heat that may heat a reactor (e.g., as in a catalytic converter on an automobile). Controlling both contact time (e.g., between a fluid and a reactor) and a temperature at which the reaction occurs may be challenging with typical reactor designs, particularly when heat transfer and mass transfer are not independently controlled.
Effective reaction (e.g., mitigation of a pollutant) may require a reactor design that maintain