Multichannel Raman Spectrometer For The Study Of Dynamical Processes In Analytical Chemistry

Abstract

A Raman polychromator system is described which makes use of a concave grating, two objectives with f-numbers lower than 1, and a multichannel detector. The system provides a very large optical throughput and should be suitable for analysis of gaseous and liquid samples -especially in cases where the concentration of the compounds investigated is rapidly varying. This is demonstrated by measurements at automobile exhaust gases and by an on -line detection of high -pressure liquid chromatography (HPLC)-fractions. Keywords: Raman spectroscopy; linear Raman spectroscopy; multichannel spectrometer; automobile exhaust gases; on -line high-pressure liquid chromatography (HPLC) /Raman. Optical Engineering 22(3), 308 -313 (May /June 1983). Keywords: Raman spectroscopy; linear Raman spectroscopy; multichannel spectrometer; automobile exhaust gases; on-line high-pressure liquid chromatography (HPLQ/Raman. Optical Engineering 22 (3), 308-313 (May/June 1983).

Quantitative Measurements of Composition, Pressure, and Density of Microvolumes of CO2–N2 Gas Mixtures by Raman Spectroscopy

“…The exploration of the Raman effect by C.V Raman in 1928 provided a new way for non-destructive analyses of materials under different phase states (solid, liquid and gaseous) to get qualitative and quantitative information (after establishing calibration data). The sensitivity of Raman spectroscopy covers a wide concentration range, down to very low concentration, 1,2 even to sub-ppm levels 3,4 . Raman spectroscopy has been widely used for gas analysis in various domains of investigation such as monitoring of polluted air 5 or automobile exhaust gases, 1 fuel gas analysis, [6][7][8] diagnosis and monitoring of disease states by human breath analysis, 3,4,9 controlling and monitoring of fruit ripening, 10 analyzing of gas bubbles appearing as defects inside industrial glasses to optimize production process.…”

“…The exploration of the Raman effect by C. V. Raman in 1928 provided a new way for nondestructive analyses of materials under different phase states (solid, liquid, and gas) to get qualitative and quantitative information (after establishing calibration data). The sensitivity of Raman spectroscopy covers a wide concentration range, down to a very low concentration , and even to sub-ppm levels. , Raman spectroscopy has been widely used for gas analysis in various domains of investigation such as monitoring of polluted air or automobile exhaust gases, fuel gas analysis, − diagnosis and monitoring of disease states by human breath analysis, ,, controlling and monitoring of fruit ripening, analyzing of gas bubbles appearing as defects inside industrial glasses to optimize production process . Other applications can also be found in the field of environmental gas sensing, e.g., monitoring of geological storage site of CO 2 , investigation of biological and/or geochemical gas exchange and migration processes within the different compartment (groundwater, subsurface, surface, atmosphere). − All applications mentioned above relate exclusively to the analysis of an immense and/or small volume of gas at relatively low pressure (<few dozen bars).…”

Raman spectroscopy

“…Several new instrumental design features have appeared during the period covered by this review including an apparatus which can be used for luminescence, time-resolved phosphorescence, and Raman measurements (39), a simple homemade microprobe (40), and a commercial microprobe (41). A new spectrograph has been produced with a multichannel optical detector for the Raman characterization of microparticles (42) and the use of multichannel detectors is expanding rapidly (43)(44)(45)(46)(47). New LIDAR systems have been described for environmental and atmospheric probing (48).…”