摘要
为了实现激光诱导击穿光谱(LIBS)技术对自然水体中痕量铬(Cr)元素的快速检测,实验以蒙脱石为吸附基底,对溶液中的Cr元素富集后进行LIBS测量。通过分析样品的发射光谱特性,确定了425.4 nm的特征谱线为Cr的分析线;并基于不同参数条件下分析线的强度和信噪比,得出最佳激光光斑尺寸为50μm,最优的激光能量为40.8 m J,最佳延迟时间为5μs。在最佳实验参数条件下,建立了水体中Cr元素的定标曲线,拟合结果显示,线性相关系数为0.989,检测限达到0.33 mg/L。研究结果为水体中重金属元素的LIBS测量提供了一种新途径。
In order to achieve rapid and high sensitive detection of chromium in natural water by laser-induced breakdown spectroscopy （LIBS）, the water samples containing chromium was enriched by montmorillonite substrates and then analyzed by laser-induced breakdown spectroscopy technique. According to the emission spectral characteris- tics of chromium adsorbed on the solid matrix, the characteristic spectral line of chromium at 425.4 nm was determined and chose as the analytical line of chromium. Measurement of the intensity and signal to noise ratio of the analytical line in different parameter occasions showed that the optimal laser spot size was 50 μm, the optimal pulse laser energy was 40. 8 mJ, and the optimal delay time was 5 μs. Under the optimized experimental conditions, the calibration curve of chromium in water was established. The linear correlation coefficient with 0. 989 indicated a good linear relationship between the chromium concentration in water and the intensity of the analytical line. The detection limit for chromium in water reached 0. 33 mg/L. This study provided a new method for the LIBS measurement of tracing heavy metal in water
作者
吴青峰
石俊
黄达
郝东元
陈善俊
熊艳
王阳恩
WU Qing-feng SHI Jun HUANG Da HAO Dong-yuan CHEN Shan-jun XIONG Yan WANG Yang-en(School of Physics and Optoelectronic Engineering, Yangtze University, Jingzhou Hubei 434023 ,Chin)
出处
《激光杂志》
北大核心
2017年第4期21-24,共4页
Laser Journal
基金
国家自然科学基金(41403083)
湖北省教育厅科学技术研究项目(D20141305)
关键词
激光诱导击穿光谱
重金属
铬元素
蒙脱石
吸附
laser induced breakdown spectroscopy
heavy metal
chromium element
montmorillonite
adsorption
