Membrane single photon ionization mass spectrometry enables real-time monitoring of volatile organic compounds at trace levels, providing important complementary information on aromatics and alkanes in the air.

A miniature reflectron time-of-flight mass spectrometer (TOF MS) with orthogonal extraction coupled with electron impact (EI) ionization source can be used to perform in situ gas composition analysis in a planetary environment. However, performances such as the mass resolution, sensitivity, limit of detection, mass range, and mass accuracy are often decreased because of miniaturization. Herein, a compact instrument for space applications has been developed, and its performance has been evaluated. The mass of the TOF MS is 13.4 kg, with dimensions of 300 mm × 200 mm × 200 mm, and the power consumption is 25 W. In this paper, the design of the ion source, mass analyzer, and detector is discussed in detail. The upper limit of the mass range is greater than 500 amu, and the best resolving power obtained so far on the miniature TOF MS is around 405 at full width half maximum (FWHM); other performance indexes of the instrument are also determined, where the worst case for mass stability is 0.49%, together with a mass accuracy of 0.12% and a sensitivity of 0.6 mV/ppm.

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This paper discusses the design and manufacture of an optical system used in a portable wear metal analyzer (PWMA).The PWMA was developed for the United States Air Force to analyze used aircraft engine oil for wear metal contents in the parts per million range. The PWMA uses the graphite furnace atomic absorption technique to detect nine wear metals simultaneously.The instrument has to perform in the field where environmental conditions are particularly challenging. The operating thermal environment spans 75 degrees C and the instrument must withstand a 30 g shock without degradation in performance afterwards. Weight and volume of this stand -alone analytical instrument are limited to what can be carried by one man.