Kääriäinen Teemu, Richmond Craig A, Manninen Albert
VTT Technical Research Centre of Finland Ltd., Vuorimiehentie 3, 02150 Espoo, Finland.
Sensors (Basel). 2018 Feb 7;18(2):496. doi: 10.3390/s18020496.
A tunable laser absorption spectrometer (TLAS) was developed for the simultaneous measurement of C and D values of methane (CH₄). A mid-infrared interband cascade laser (ICL) emitting around 3.27 µm was used to measure the absorption of the three most abundant isotopologues in CH₄ with a single, mode-hop free current sweep. The instrument was validated against methane samples of fossil and biogenic origin with known isotopic composition. Three blended mixtures with varied biogenic content were prepared volumetrically, and their C and D values were determined. Analysis demonstrated that, provided the isotopic composition of the source materials was known, the C and D values alone were sufficient to determine the biogenic content of the blended samples to within 1.5%.
开发了一种可调谐激光吸收光谱仪（TLAS），用于同时测量甲烷（CH₄）的碳和氘值。使用发射波长约为3.27 µm的中红外带间级联激光器（ICL），通过单次无跳模电流扫描来测量CH₄中三种最丰富的同位素异构体的吸收。该仪器针对具有已知同位素组成的化石源和生物源甲烷样品进行了验证。通过体积法制备了三种生物源含量不同的混合混合物，并测定了它们的碳和氘值。分析表明，如果源材料的同位素组成已知，仅碳和氘值就足以将混合样品的生物源含量确定在1.5%以内。
