Abstract: A fuel cell system, in particular for a motor vehicle, has a fuel cell stack arranged in a housing and a measure for ventilating this housing by coupling the ventilation stream to another gas stream. The ventilation stream is fed to an air stream which is conducted through a radiator of the fuel cell system. The radiator is an ambient air heat exchanger. If the ventilation stream is fed in upstream of the radiator, a venting opening in the housing can be placed in such a way that the ventilation stream is entrained to the radiator by the inflow air stream. Alternatively, the ventilation stream can be fed to an exhaust gas stream of the fuel cell stack and the latter can be fed to the outflow stream of the radiator. A sensor for determining the hydrogen content in a gas stream downstream of the point where the ventilation stream is fed may be provided.

Abstract: A fuel cell system, in particular for a motor vehicle, has a fuel cell stack arranged in a housing and a measure for ventilating this housing by coupling the ventilation stream to another gas stream. The ventilation stream is fed to an air stream which is conducted through a radiator of the fuel cell system. The radiator is an ambient air heat exchanger. If the ventilation stream is fed in upstream of the radiator, a venting opening in the housing can be placed in such a way that the ventilation stream is entrained to the radiator by the inflow air stream. Alternatively, the ventilation stream can be fed to an exhaust gas stream of the fuel cell stack and the latter can be fed to the outflow stream of the radiator. A sensor for determining the hydrogen content in a gas stream downstream of the point where the ventilation stream is fed may be provided.

Abstract: Superconducting Gamma-ray and fast-neutron spectrometers with very high energy resolution operated at very low temperatures are provided. The sensor consists of a bulk absorber and a superconducting thermometer weakly coupled to a cold reservoir, and determines the energy of the incident particle from the rise in temperature upon absorption. A superconducting film operated at the transition between its superconducting and its normal state is used as the thermometer, and sensor operation at reservoir temperatures around 0.1 K reduces thermal fluctuations and thus enables very high energy resolution. Depending on the choice of absorber material, the spectrometer can be configured either as a Gamma-spectrometer or as a fast-neutron spectrometer.

Abstract: Superconducting Gamma-ray and fast-neutron spectrometers with very high energy resolution operated at very low temperatures are provided. The sensor consists of a bulk absorber and a superconducting thermometer weakly coupled to a cold reservoir, and determines the energy of the incident particle from the rise in temperature upon absorption. A superconducting film operated at the transition between its superconducting and its normal state is used as the thermometer, and sensor operation at reservoir temperatures around 0.1 K reduces thermal fluctuations and thus enables very high energy resolution. Depending on the choice of absorber material, the spectrometer can be configured either as a Gamma-spectrometer or as a fast-neutron spectrometer.