【摘要】 <正> 粉末试样直接引入ICP的分析方法,曾吸引许多人的研究。著者曾设计粉末进样器,解决了稳定、均匀送样进入ICP,而样品在ICP中的蒸发及激发仍是悬而未决的问题。因为它必须解决试样与标样中元素含量与赋存状态的差异,粉末粒度的影响及进样量增大引起ICP放电特性改变等问题。为此,陈学智等采用缓冲剂;Shao和Horlick用NaF作为蒸发改进剂;Elalfy等用NH₄Cl及高功率的ICP光源;吴朝衡更多还原

【Abstract】 This paper describes an ICP-arc dual discharge system for direct powder sample introduction, which consists of an AC arc placed horizontally in an extension tube at 11 mm above the working coil of a conventional torch, and a powder introduction device was described earlier. With this additional arc discharge, the energy can be coupled directly to the plasma for improvement of powder sample evaporation and excitation, and the effects of particle size, the interference of coexisted elements and matrix can be alleviated or eliminated, In comparison with conventional direct powder sample introduction, the net signal and signal-to-background ratio can be improved in a higher observation height. The factors, such as RF power, carrier gas flow rate, observation height as well as parameters for auxiliary arc discharge, affecting the net signal intensity and signal-to-background ratio are optimized. The D. L. and RSD of the tests for ten elements in SiO₂ powder samples are measured in the present work.更多还原