Long path DOAS measurements of atmospheric pollutants concentration

A differential optical absorption spectroscopy gas-analyzer consisted of a coaxial telescope, a spectrometer, an analyzer and retroreflector was successfully tested. A high pressure 150-W Xe arc lamp was employed as a light source. In order to record the spectra, a monochrometer with a grating and photodiode array was used. Gas analyzer spectral data bank includes more than 35 moleculas absorbed in UV spectral region. The measured absorption spectra were evaluated by using a least-squares fit to determine the average mixing ratio of each species in the atmosphere. As a result of experiments time series of concentrations of gases polluting the atmosphere were trace measured. Minimally detected concentration on pathlength 480 m is the unit of ppb at the time of accumulation of 2 min. The results of the field test measurements of pollutants in Tomsk city are presented

Development and implementation of UV absorption gas analysis techniques for ecological monitoring of the atmosphere

Stationary nonlaser gas analyzers have been designed since the 1990s at the Institute of Monitoring of Climatic and Ecological Systems, Siberian Branch, Russian Academy of Sciences, on the basis of the classical differential absorption method for monitoring the content of nitrogen and sulfur oxides in exhaust gases of thermal power plants, which burn natural gas, coal, and fuel oil. The operation of gas analyzers at Russian thermal power plants has shown their high sensitivity, reliability, and ease of maintenance. Based on the differential optical absorption spectroscopy and UV LEDs, a prototype of a portable energy-independent gas analyzer has been designed. It is an effective tool for simultaneous long-path measurements of concentrations of several atmospheric gases. An atomic absorption mercury analyzer has been created, where a capillary lamp with mercury of natural isotopic composition and the transverse Zeeman effect is used as a radiation source. A technique for detecting mercury in different media has been designed; the sensitivity of the analyzer is 14 ng/m(3). Its applicability to multipurpose mercury monitoring is shown

Long path DOAS measurements of atmospheric pollutants concentration

A differential optical absorption spectroscopy gas-analyzer consisted of a coaxial telescope, a spectrometer, an analyzer and retroreflector was successfully tested. A high pressure 150-W Xe arc lamp was employed as a light source. In order to record the spectra, a monochrometer with a grating and photodiode array was used. Gas analyzer spectral data bank includes more than 35 moleculas absorbed in UV spectral region. The measured absorption spectra were evaluated by using a least-squares fit to determine the average mixing ratio of each species in the atmosphere. As a result of experiments time series of concentrations of gases polluting the atmosphere were trace measured. Minimally detected concentration on pathlength 480 m is the unit of ppb at the time of accumulation of 2 min. The results of the field test measurements of pollutants in Tomsk city are presented