Near Infrared Absorption of Ethylene between 8200 cm 1 and 9500 cm " 1 to High Pressures and Temperatures
نویسنده
چکیده
The near infrared absorption of pure ethylene in the region of the second overtone of the C-H stretching fundamentals (8200 c m 1 to 9500 c m J ) was measured at supercritical temperatures {Tc = 9.5 °C) between 22 °C and 200 °C from 0.7 bar to 3000 bar. The density and temperature dependence of bandshape, maximum frequency and absorption intensity are reported and discussed. The bands observed within a wide range of experimental conditions are assigned to combination and overtone modes. The molar integrated intensity determined between the wavelength of maximum absorption and the high frequency absorption boundary was observed to be independent of pressure and temperature. This enables spectroscopic concentration determinations on ethylene in high pressure — high temperature phase equilibria and reactions.
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