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A one-dimensional two-phase model of an adsorptive catalytic monolith reactor is used to analyze the Lean NOx Trap (LNT). The model simulates the features of NOx storage and reduction (NSR), a periodic process involving the sequential trapping on a storage component and conversion of NOx to nitrogen on a precious metal catalyst under lean conditions found in the exhaust of lean burn and diesel vehicles. A detailed storage kinetic model is used for the simulations. The NOx storage phase on Pt/BaO/Alumina catalyst has been studied in detail with particular attention to the effect of fluid velocity, storage time and storage component loading. The reductive phase is also analyzed. The simulated results are compared with our lab experimental data. The model predictions are in good agreement with the experimental observations and trends reported in the literature.

Membranes are highly desirable for separating gases in life-support applications. They are small, light, efficient, selective and require little operational or physical maintenance. Facilitated transport membranes have particularly high flux and selectivity. We created enzyme-based facilitated transport membranes using isozymes and mutants as immobilized arrays alone and in conjunction with polymeric membranes. The enzyme operates efficiently at the low CO2 concentrations encountered in respiratory gases and can bring CO2 to near ambient levels. CO2 flux is greatly enhanced and selectivities for CO2 over O2 of 200:1 or greater are possible. The enzymes are robust and stable for long periods under a variety of storage and use conditions.

In preparation for the 21st Century, NASA Johnson Space Center is designing and building a habitat (Bio-Plex) intended for use in long duration missions where all life support systems will be recycled and reused. Crops grown on-board will be used for air and water recycling and also serve as a food source. Space food development for Bio-Plex marks a departure from previous NASA missions yet some basic principles still apply. The differences and similarities will be discussed. The United States space food program has progressed from tubes and cubes in the earlier years to eating familiar food from open containers using normal utensils. All space food development problems include weight and volume restrictions, nutrition, crew acceptability and consumption, and management of food generated waste. To date, food for spaceflight has been carried onboard or delivered in space. Preparation has been limited to rehydration and heating to serving temperature.