延迟时间对灰岩中镍元素激光诱导击穿光谱强度的影响

为了提高激光诱导击穿光谱的信噪比，从理论上讨论了激光诱导击穿光谱信号与延迟时间之间的关系。利用激光诱导击穿光谱仪对GBW07716合成灰岩标准样品进行了测试，并分析了NiI305.432nm、NiI313.411nm、NiI351.505nm等3条谱线强度随延迟时间的变化特征。结果表明，谱线随延迟时间的变化趋势主要与能级的寿命有关，而不是跃迁几率A_ij。当延迟时间大于2μs时，从同一高能级辐射出来的谱线随延迟时间的变化趋势相同，而从不同高能级跃迁到同一低能级的谱线随延迟时间的变化趋势不相同。

Influence of delay time on laser-induced breakdown spectroscopy intensity of nickel in limestone

To improve the signal to noise ratio of laser-induced breakdown spectroscopy,a relation between the signals of laser-induced breakdown spectroscopy and the delay time was discussed in theory. The tests on the GBW07716 synthetic limestone certified reference samples with laser-induced breakdown spectrometerwere conductedand the changes in such lines as Ni I 305.432 nm,Ni I 313.411 nm and Ni I 351.505 nm with the delay time were analyzed. The results showed that the changes of spectral lines with delay time were mainly closely related with the life of energy level instead of the transition probability A_ij. When delay time surpassed 2 μs,the spectral lines emitted from the same high level exhibited the same trend along delay time,while the spectral line transited from different energy levels to the same lower energy level showed discrepancy in their changes with delay time.