Determination of nitrogen dioxide by pulsed thermal lens spectrophotometry

Modern analytical thermooptical spectroscopy

“…61,62,81 Thermooptical spectroscopy methods were used for determining various organic compounds, primarily, those containing nitrogen or sulfur. 32 ± 36, 69, 71, 184, 379 In addition to studies of artificial mixtures serving for comparison of different modes of chromatographic separation, several studies were devoted to analysis of natural substances, 21,26,36,37 in particular, to analysis of industrial and household dyes, 306 and examination of the possibility of controlling products of organic synthesis. 25 Studies dealing with the determination of proteins at a level of 1 ± 100 ng 26,38,66,76,85,304,379 and amino acids at concentrations of y610 715 ± y610 712 mol litre 71 also deserve attention.…”

Thermal lens spectrophotometry using a tunable infrared laser generated by a stimulated Raman effect

“…It is noteworthy that the resolution of the spectrum can be improved by reducing the total pressure of the sample and the line width of the dye laser should be narrowed for further improvement. The sensitivity of pulsed thermal lens spectrophotometry is reported to be independent to the total pressure of the sample (13). Therefore, we expect that the present method is very promising for high-resolution spectrometry of trace molecules in the infrared region.…”

Laser spectroscopy on organic molecules

“…This approach was called thermal lens spectrometry [12]. The relative sensitivity of conventional absorption spectrometry was reported for liquid and gas samples under CW and pulsed laser excitations, indicating that a pulsed laser is useful for trace analysis of gases and a CW laser for liquids [13,14]. Similarly, beam deflection resulting from the refractive index gradient was measured in thermal deflection spectrometry [15], and the beam diffraction resulting from an interference pattern thermally-induced by a crossed beam, was recorded in thermal grating spectrometry [16].…”