title: AC reflectometry: a sensitive method of measuring smoke or reactive gas in air.
mesh_terms: D000397:Air Pollution / Q000032:analysis*; D002621:Chemistry / Q000295:instrumentation*; D003124:Colorimetry; D005374:Filtration; D005740:Gases / Q000032:analysis*; D006862:Hydrogen Sulfide / Q000032:analysis; D008722:Methods; D012906:Smoke / Q000032:analysis*
chemical_list: D005740:Gases; D012906:Smoke; D006862:Hydrogen Sulfide