We investigated the influence of permeated oxygen on recovering from carbon monoxide (CO) poisoning when polymer electrolyte fuel cells start or stop. Anode oxygen concentration was measured and single cell tests in the hydrogen circulation system were conducted at two different gas atmospheres while the fuel cell was stopping. When the anode becomes an air atmosphere while the cell is being stopped, the voltage after restart fully recovered due to the CO electrochemical oxidation by increased anode overpotential. The voltage after restart was partly recovered compared to the voltage before even when the anode remains hydrogen atmosphere under stopping conditions. These results clearly demonstrate that the permeated oxygen mitigates the performance decrease caused by CO poisoning.

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An epidemiological study of automobile emission gas concentration was conducted. This paper reports a detailed automobile emission data construction and a methodology for calculating diffusion. The target area is Katsushika Ward, Tokyo. Calculated emission data are composed of (1) running exhaust emission (on trunk and narrow roads), (2) road dust and tire wear, and (3) start exhaust emission. AIST-ADMER is used for calculating diffusion with a grid size of 100m. Observed and estimated SPM concentration almost matched after correction of background concentration, which includes concentration caused by non-vehicular emission and flow from the surrounding target area. However, to improve accuracy, higher resolution and consideration of road overpasses are required.

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[in Japanese]

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[in Japanese]

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[in Japanese]

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