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A new multicomponent exhaust gas analyzer has been applied to investigate the time-resolved concentrations of the aromatic hydrocarbon exhaust components benzene, toluene, xylene, trimethyl benzene under dynamic engine operation, such as sudden change of speed and load, misfiring and switching off the fuel mixture control. The analyzer consisting of a compact laser mass spectrometer is capable of measuring the concentrations of the individual aromatic hydrocarbon compounds simultaneously with 1 ppm sensitivity at a sampling rate of 50 Hz corresponding to a sampling period of 20 ms. High concentration peaks are observed for these substances at instationary motor operation. However, whereas the real-time concentrations of toluene, xylene, and trimethyl benzene show equal dependence on motor speed and load a different behavior has been observed for benzene even during the emission phase of single combustion cycles.

A sensitive laser mass spectrometer has been developed for fast multicomponent automotive exhaust analyses. The system is particularly appropriate for working at dynamic motor test stands and provides the following features: Detection of all individual organic and inorganic exhaust constituents with 1 ppm sensitivity Simultaneous detection of up to 12 selectable exhaust compounds with a measurement rate of up to 100 Hz 2 ms time precision relative to the motor phase - Ruggedness for operation at engine test facilities This system has been used at a motor test facility to investigate the emissions of aromatic hydrocarbons benzene, toluene, xylene, and of nitrogen oxide in stationary and dynamic engine operation. These measurements demonstrate some of the capabilities of the analysis system to obtain fundamental information about the combustion processes and about processes in the exhaust pipe.

A sensitive laser mass spectrometer is being developed for fast multicomponent engine exhaust analyses. The features of the system meet the requirements of the analysis problems at dynamic motor test stands: detection of all organic and inorganic exhaust constituents of concentrations higher than 1 ppm simultaneous detection of up to 12 selectable exhaust compounds with 100 Hz repetition rate 2 millisecond time precision relative to the motor phase. precise sampling location everywhere in the exhaust pipe system, e.g. single valve or cylinder exhaust gas analysis ruggedness for operation at engine test facilities The time and space resolution allows the tracking of the different exhaust components during one and more motor cycle in static and transient engine operations. This information is essential for an understanding of the combustion processes, which is necessary for the development of the engine and engine control and other efforts to reduce emission of pollutants.

The COLUMBUS pressurized modules APM and PM2 are designed for a useful lifetime of 30 years. The APM, which forms part of the International Space Station, will be permanently manned with a 3-men-crew. The PM2, which is the pressurized module of the Men-Tended-Free-Flyer (MTFF) will be manned for the servicing period of 10 days followed by a 180-day unmanned period. In order to protect the crew from contamination by hazardous substances, which may be present in the cabin air, effective contamination management is required. This consists of a contamination monitoring system to detect and measure trace gases in the cabin atmosphere, and a contamination control system to be able to maintain the concentration of each potential contaminant below the maximum allowable concentration.