Highly Sensitive, Calibration-Free WM-DAS Method for Recovering Absorbance-Part II: Experimental Analysis
Highly Sensitive, Calibration-Free WM-DAS Method for Recovering Absorbance-Part II: Experimental Analysis
复制标题
用于恢复吸光度的高灵敏度、免校准 WM-DAS 方法第二部分：实验分析
DOI：
10.3390/s20030616
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发表时间：
2020
期刊：
影响因子：
3.9
通讯作者：
Yanjun Ding
中科院分区：
文献类型：
--
作者：
Zhimin Peng;Yanjun Du;Yanjun Ding
在第一部分的理论工作之后，在本实验研究中，在高温管式炉中实验验证了所提出的波长调制直接吸收光谱（WM-DAS）方法的鲁棒性、时间分辨率和窄扫描性能。通过提取光强的特征谱，可以有效地消除电磁噪声和其它随机频率噪声。在大气压下，研究了调制频率为0.1 ~ 100 kHz，扫描指数为3.3 ~ 11.1的WM-DAS的性能。所提出的方法产生准确的线轮廓和高信噪比超过500一致，即使在弱吸收。作为真实的应用，测量了CO在4300.6999 cm（-1）处的谱线参数，包括碰撞加宽、迪凯窄化以及它们与温度的关系。此外，高速测量（1 ms）的麦肯纳平火焰的温度和CO浓度的演示。
Following the theoretical work in Part I, in this experimental study, the robustness, temporal resolution, and the narrow scan performance of the proposed wavelength modulation-direct absorption spectroscopy (WM-DAS) method are experimentally validated in a high-temperature tube furnace. The electromagnetic and other random-frequency noises can be effectively eliminated by extracting the characteristic spectra of the light intensity. The performance of WM-DAS with modulation frequencies from 0.1 to 100 kHz and scan indexes from 3.3 to 11.1 are also investigated at atmospheric pressure. The proposed method produces accurate line profile and high SNR over 500 consistently even with a weak absorption. As for real applications, the spectral line parameters of CO at 4300.6999 cm(-1) including the collisional broadening, Dicke narrowing, and their dependence on temperature are measured. Furthermore, the high-speed measurement (1 ms) of the temperature and CO concentration of a McKenna flat flame are demonstrated.