Time-Resolved Broadband Cavity-Enhanced Absorption Spectroscopy behind Shock Wave
Time-Resolved Broadband Cavity-Enhanced Absorption Spectroscopy behind Shock Wave
复制标题
冲击波背后的时间分辨宽带腔增强吸收光谱
DOI：
10.1021/acs.jpca.6b01069
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发表时间：
2016
期刊：
影响因子：
--
通讯作者：
Kazuo Takahashi
中科院分区：
文献类型：
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作者：
Akira Matsugi;Hiroumi Shiina;Tatsuo Oguchi;Kazuo Takahashi
在激波管中应用宽带腔增强吸收光谱技术（BBCEAS），发展了一种快速、灵敏的宽带吸收技术，用于高温化学动力学和光谱测量。该方法在280-420 nm波长范围内，有效吸收路径长度为60-200 cm，腔增强因子为12-40，能够在一次实验中同时记录波长为32 nm的吸收时间曲线，时间分辨率和光谱分辨率分别为5 μs和2 nm。的动力学和光谱测量的准确性进行了检查，通过调查高温反应和吸收光谱的甲醛反射冲击波后使用1，3，5-三恶烷作为前体。得到的1，3，5-三恶烷（生成三个甲醛分子）和甲醛（生成HCO + H）的热分解反应速率常数与文献数据吻合得很好。在955、1265和1708 K的反射冲击后温度下，测定了甲醛在280 ~ 410 nm之间的高温吸收截面。结果表明，BBCEAS技术的适用性，在高温下的时间和波长分辨灵敏的吸收测量。
A fast and sensitive broadband absorption technique for measurements of high-temperature chemical kinetics and spectroscopy has been developed by applying broadband cavity-enhanced absorption spectroscopy (BBCEAS) in a shock tube. The developed method has effective absorption path lengths of 60–200 cm, or cavity enhancement factors of 12–40, over a wavelength range of 280–420 nm, and is capable of simultaneously recording absorption time profiles over an ∼32 nm spectral bandpass in a single experiment with temporal and spectral resolutions of 5 μs and 2 nm, respectively. The accuracy of the kinetic and spectroscopic measurements was examined by investigating high-temperature reactions and absorption spectra of formaldehyde behind reflected shock waves using 1,3,5-trioxane as a precursor. The rate constants obtained for the thermal decomposition reactions of 1,3,5-trioxane (to three formaldehyde molecules) and formaldehyde (to HCO + H) agreed well with the literature data. High-temperature absorption cross sections of formaldehyde between 280 and 410 nm have been determined at the post-reflected-shock temperatures of 955, 1265, and 1708 K. The results demonstrate the applicability of the BBCEAS technique to time- and wavelength-resolved sensitive absorption measurements at high temperatures.