Line strengths of some selected transitions in the 2900-cm-1 region of H2CO

摘要

Abstract: Formaldehyde has been known as an air pollutant for some time. Most measurement techniques have been based upon wet chemistry. With the improvement of diode lasers, fast high-precision measurements can now be made using selected rotation-vibrational transitions in the IR region. It is very important to accurately measure the line intensity if you want to make reliable concentration measurements. Line strengths of several rotation- vibrational transitions of formaldehyde in the 2900 CM$+$MIN@1$/ region have been measured with a tunable diode laser spectrometer system. The resulting line strengths are compared with the corresponding values in the 1992 version of HITRAN and are found to be a factor of 1.10$POM@0.03 larger. Measurements of the self- broadening constant of several transitions are also made with an average measured value of 6.6$POM@0.1 CM$+$MIN@1$/ MPa$+$MIN@1$/ (0.67$POM@0.01 CM$+$MIN@1$/atm$+$MIN@1$/). Intensities of multiple assigned formaldehyde transitions in the HITRAN compilation is also presented. Initial studies of permeation devices to deliver known concentration of formaldehyde is also investigated. The stability of these devices is presented. !17