The Li-6400XT (LI-COR Biosciences UK Ltd, www.licor.com) allows automatic measurements of the CO2 and water vapour concentrations in leaf and needles as well as chlorophyll fluorescence. The Li-COR 6400XT has two absolute and non-dispersive infrared analyzers allowing precise real-time measurements.
The infrared radiation passes into the leaf chamber and is twice reflected by mirrors to enhance the signal and to improve the signal-to-noise ratio. Then the infrared beam passes through the filters, that are highly specific for CO2 and H2O. The CO2 and H2O concentrations are continuously measured at both reference and sample compartments. The CO2 concentration in the incoming stream can be set up and controlled within 1 ppm resolution between 50 to 2000 μmol-1. The LI6400XT controls the chamber humidity by automatically varying the flow rate. Gas exchange measuring system was used in the following research papers: Wang J. et al, Front Plant Sci. 2016; 7: 250, 
Location: room B3-38-51