The DF laser's capabilities for monitoring natural gas and petroleum products in pipeline areas are considered. The absorption coefficients of methane, ethane, and propane were determined experimentally for 11 spectral lines in the 3.55-3.75 mu m range of the DF laser output.The criteria were formulated for selecting analytic and reference lines suitable for measuring atmospheric hydrocarbons by means of the differential absorption technique. Combinations of analytic and reference lines were chosen according to these criteria. The laboratory mock-up of hydrocarbon analyzer implemented around a DF Laser was tested.

A report is given of the methodology and of the results of measurements of the relative spectral reflection coefficients for separate emission lines of a DF laser in the range lambda = 3.6-4 mu m reflected by five typical topographic objects. Estimates are given of possible errors in the measurement of hydrocarbon concentrations in air by a lidar system based on a DF laser and utilising topographic objects as retroreflectors.

A study was made of a possible use of a DF laser as a radiation source in the analysis of atmospheric hydrocarbons. The absorption coefficients of methane, ethane, and propane were determined at various emission wavelengths of the DF laser. Criteria were formulated for selecting the analytic and reference emission lines to be used in the monitoring of atmospheric hydrocarbons by the differential absorption method. The methane monitoring sensitivity was ∼ 2 × 10-3 bar m and the propane sensitivity was 10-3 bar m.

Performance has been investigated of a broadband chemical laser utilizing chain and nonchain reactions and emitting simultaneously from excited HF* and DF* molecules. Simultaneous stimulated emission of radiation in the spectral ranges of 2.7-3.0 mu m and 3.7-4.1 mu m has been obtained. Theoretical dependencies are presented of laser energy characteristics on the ratio of initial H-2 and D-2 concentrations in a working mixture.

An experimental investigation was made of the influence of the replacement of the working mixture and of the mixture composition on the output characteristics of a pulse-periodic electric-discharge chemical DF laser. The laser had an open gas-flow channel and its operation was based on chain and nonchain reactions. The investigation was carried out at pulse repetition frequencies from 10 to 50 Hz.

The second harmonic generation of DF laser radiation is realized for the first time. Using monocrystals of ZnGeP2 10.1 and 13.6 mm long we obtained total scheme efficiency of 4 and 6.2 %, inner crystall efficiency being 7.6 and 11.8 % respectively.

The operation was studied of a wide-band chemical laser utilizing chain and nonchain reactions and emitting due to both HF* and DF* excited molecules. Radiation was emitted simultaneously in the 2.7–3.0 μm and 3.7–4.1 μm spectral ranges. The dependences of the laser energy characteristics on the ratio of the initial H2 and D2 concentrations in the active mixture were calculated.