The fluorine and bromine limits of detection (LoDs), based on emission from CaF and CaBr, using Microwave-assisted Laser Induced Breakdown Spectroscopy (MW-LIBS) have been determined. The molecular emission bands of CaF and CaBr in the spectral range of 605 nm and 627.1 nm are utilised for quantitative fluorine and bromine detection. The optimum gating has been established for CaF, at 603.3 nm and 605 nm, following 1.5 ms long microwave pulses. The MW-LIBS plasma temperature and electron density against laser energy have been demonstrated at constant microwave power coupling to optimise laser energy using Ca I lines. A linear relationship between the CaF signal strength and fluorine concentration, and CaBr signal strength and bromine in cement has been validated. The recorded limits of fluorine and bromine detection were 106 ± 6 μg g⁻¹ and 0.2 ± 0.04%, respectively. The results represent an improved detection limit at low laser energy and 4-fold improved detection limit for bromine.

中文翻译：

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通过分子发射在环境条件下定量检测氟和溴

基于微波和激光诱导击穿光谱法（MW-LIBS）的CaF和CaBr发射，已经确定了氟和溴的检出限（LoDs）。CaF和CaBr的分子发射带在605 nm和627.1 nm的光谱范围内用于定量检测氟和溴。在1.5 ms长的微波脉冲之后，已经确定了CaF的最佳门控频率为603.3 nm和605 nm。在恒定的微波功率耦合条件下，已经证明了MW-LIBS等离子体温度和电子密度相对于激光能量的影响，可以使用Ca I线优化激光能量。已经验证了水泥中CaF信号强度和氟浓度以及CaBr信号强度和溴之间的线性关系。记录的氟和溴检出限为106±6μgg^-1和0.2±0.04％。结果表明在低激光能量下检测限提高了，溴检测限提高了4倍。