A Low-Cost NDIR-Based NO Gas Detection Device for Agricultural Soils: Assembly, Calibration Model Validation, and Laboratory Testing.

This research presents a low-cost, easy-to-assemble nondispersive infrared (NDIR) device for monitoring NO gas concentration in agricultural soils during field and laboratory experiments. The study aimed to develop a cost-effective instrument with a simple optic structure suitable for detecting a wide range of soil NO gas concentrations with a submerged silicone diffusion cell. A commercially available, 59 cm path-length gas cell, microelectromechanical systems (MEMS)-based infrared emitter, pyroelectric detector, two anti-reflective (AR) coated optical windows, and one convex lens were assembled into a simple instrument with secure preciseness and responsivity.