On-line Detection Of Atmospheric Sulfides Based On Laser Spectroscopy

On-line detection of pollutants has always been a hot topic concerned by domestic and foreign research teams.With the outbreak of smog,smoke,acid rain,etc.,more and more attention has been paid to the air pollution problem from around.Among them,one of the major hazards to health and the natural environment is atmospheric sulfide.Atmospheric sulfides mainly exist in the atmosphere in two states,gaseous and aerosol.Atmospheric sulfides also participate in the atmospheric and water cycles and causes water pollution.Therefore,it is extremely important to develop an in-situ online detection method for atmospheric sulfides.Laser-induced breakdown spectroscopy(LIBS)has obvious advantages in in-situ online detection of atmospheric pollutants.In this paper,a high-sensitivity LIBS spectral detection system was built.In the atmospheric environment,the on-line detection of sulfur-containing compounds in both gaseous and aerosol states was carried out.For the first time,the LIBS ion spectrum of sulfur element in the visible light band was detected in the atmospheric environment,the spectrum was calibrated,and the temperature of the CN molecular spectrum was simulated.In addition,through quantitative experiments,the calibration curve of gaseous sulfide was obtained,and the detection limit of the detection system was calculated.At the same time,single particle aerosol mass spectrometry(SPAMS)technology was applied in the detection of atmospheric sulfide in aerosol state.Not only important data such as aerosol particle size were measured,but also online detection of atmospheric sulfide isotopes was realized.Finally,in view of the shortcomings of the existing detection system,the direction and technical scheme of improvement and expansion were proposed.In order to make up for the shortcomings of LIBS in molecular spectroscopy detection and material structure analysis.And realize on-line detection of liquid sulfide.A laser Raman spectroscopy detection system was built.The experimental results of Raman spectroscopy were combined with density functional theory(DFT).The Raman spectra of common sulfides were marked,and the molecular vibration modes of some spectral characteristic peaks were studied in depth.Raman spectroscopy is also used in the identification and detection of isomers,which is an important supplement to the LIBS detection of atmospheric sulfides.The above work not only meets the major strategic needs of our country,but also is an important development direction for the optoelectronic industry.It provides a reliable theoretical basis and technical support for the monitoring and control of atmospheric sulfides.