Morales-Rodriguez Marissa E, McFarlane Joanna, Kidder Michelle K
Oak Ridge National Laboratory, USA.
The Bredesen Center at the University of Tennessee Knoxville, USA.
Int J Anal Chem. 2018 Sep 23;2018:7896903. doi: 10.1155/2018/7896903. eCollection 2018.
We describe a new approach for high sensitivity and real-time online measurements to monitor the kinetics in the processing of nuclear materials and other chemical reactions. Mid infrared (Mid-IR) quantum cascade laser (QCL) high-resolution spectroscopy was used for rapid and continuous sampling of nitrates in aqueous and organic reactive systems, using pattern recognition analysis and high sensitivity to detect and identify chemical species. In this standoff or off-set method, the collection of a sample for analysis is not required. To perform the analysis, a flow cell was used for in situ sampling of a liquid slipstream. A prototype was designed based on attenuated total reflection (ATR) coupled with the QCL beam to detect and identify chemical changes and be deployed in hostile environments, either radiological or chemical. The limit of detection (LOD) and the limit of quantification (LOQ) at 3 for hydroxylamine nitrate ranged from 0.3 to 3 and from 3.5 to 10 g·L, respectively, for the nitrate system at three peaks with wavelengths between 3.8 and 9.8 m.
我们描述了一种用于高灵敏度实时在线测量的新方法，以监测核材料处理及其他化学反应中的动力学过程。中红外（Mid-IR）量子级联激光器（QCL）高分辨率光谱法用于在水性和有机反应体系中对硝酸盐进行快速连续采样，利用模式识别分析和高灵敏度来检测和识别化学物质。在这种远距离或非接触式方法中，无需采集样品进行分析。为进行分析，使用流通池对液体分流进行原位采样。基于衰减全反射（ATR）与QCL光束耦合设计了一个原型，以检测和识别化学变化，并可部署在放射性或化学性的恶劣环境中。对于硝酸羟胺，在波长介于3.8至9.8μm的三个峰处，硝酸盐体系的检测限（LOD）和定量限（LOQ）分别为0.3至3 g·L和3.5至10 g·L。
