J.R. Engel's scientific contributions

... Otherwise, concern for CO toxicity would prevent crew occupancy of the greenhouse. As shown in the figure, the system comprises the following process steps: 1) Capture CO2-laden gas from a simulated Mars atmosphere, 2) remove dust particulates with a two-stage filtration unit, 3) compress the gas flow, 4) selectively permeate 150 g CO2/day through the temperature-controlled SILM to the sweep gas, 5) collect and store the exhaust gases from the process stream, 6) control the CO2-laden sweep gas stream to the greenhouse, 7) plants take up CO2 and produce O2 along with ethylene, 8) a blower circulates the gas flow, 9) condense, separate and collect water vapor from the sweep gas stream leaving the plant growth chamber, 10) remove ethylene and catalytically oxidize carbon monoxide and other volatiles toxic either to plants or the crew, 11) separate excess O2 from the sweep gas flow, and 12) return the sweep gas to the SILM for replenishment of CO2. ...