METHOD OF MEASURING TRACE ELEMENTS IN AIR STREAM Russian patent published in 2012 - IPC G01N15/00 

FIELD: physics.

SUBSTANCE: invention relates to analytical methods of measuring impurities in a gas, which is based on converting impurity molecules into aerosol particles and subsequent detection of the aerosol, and can be used in high-sensitivity gas analysers used to solve environmental problems, as well as in diagnosis of diseases by analysing exhaled air. The method of measuring trace elements in an air stream involves converting impurity molecules into a condensation nucleus. The nuclei undergo two-step enlargement to size of aerosol particles in supersaturated vapour of the detecting substances in thermodiffusion-type condensation devices and light-scattering of the obtained aerosol is measured. To perform conversion, the stream is heated to 200-600°C, and the detecting substance used at the first enlargement step is semi-volatile organic acids with ionisation constant in water of 4·10^-2-2·10^-1.

EFFECT: high sensitivity and selectivity of detecting ammonia and organic amines in atmospheric air.

1 tbl, 6 dwg