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The potential of an iron(III) corrole complex for use in the detection of nitric oxide (NO) was investigated. The reversible conversion of an dissolved iron(III) corrole to its corresponding nitrosyl complex using gaseous nitric oxide was monitored by UV/Vis spectroscopy. The spectral differences between both coordination compounds were used to determine photometrically small amounts of nitric oxide in the sub‐parts‐per‐million range. The spectral changes due to NO binding were assigned to charge‐transfer transitions arising upon NO coordination and were analyzed in detail with support from quantum chemical calculations. Finally, films of the iron(III) corrole were deposited on quartz glass. Thus, the great potential of iron(III) corroles for the development of advanced, highly sensitive and low‐energy‐consuming photonic sensing devices was demonstrated.

Abstract. Due to the ban on hydrofluorocarbon and haloalkane refrigerants with a high global warming potential, such as R134a, in the automotive industry, the significance of reliable and precise measuring devices for these refrigerants has risen. We present a photoacoustic gas detector for monitoring the organofluorine-based refrigerants R134a and R1234yf. The idea for this sensor is based on the three-chamber concept (a detection chamber, absorption chamber, and filter chamber). The optimal parameters and dimensions of the photoacoustic sensor components were determined via simulations. The simulation results were the cornerstone of our hardware construction. The first measurements with the newly developed sensor showed a sufficient signal-to-noise ratio for a reliable 0.5 vol. % (0.005 m3 m−3) detection resolution. The influence and importance of the filter chamber were examined and validated.

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A multi-sensor system is a chemical sensor system which quantitatively and qualitatively records gases with a combination of cross-sensitive gas sensor arrays and pattern recognition software. This paper addresses the issue of data analysis for identification of gases in a gas sensor array. We introduce a software tool for gas sensor array configuration and simulation. It concerns thereby about a modular software package for the acquisition of data of different sensors. A signal evaluation algorithm referred to as matrix method was used specifically for the software tool. This matrix method computes the gas concentrations from the signals of a sensor array. The software tool was used for the simulation of an array of five sensors to determine gas concentration of CH 4 , NH 3 , H 2 , CO and C 2 H 5 OH. The results of the present simulated sensor array indicate that the software tool is capable of the following: (a) identify a gas independently of its concentration; (b) estimate the concentration of the gas, even if the system was not previously exposed to this concentration; (c) tell when a gas concentration exceeds a certain value. A gas sensor data base was build for the configuration of the software. With the data base one can create, generate and manage scenarios and source files for the simulation. With the gas sensor data base and the simulation software an on-line Web-based version was developed, with which the user can configure and simulate sensor arrays on-line.