Zaray G, Broekaert J A, Böhmer R G, Leis F
Institut für Spektrochemie und angewandte Spektroskopie, Postfach 778, D-4600 Dortmund 1, Federal Republic of Germany.
Talanta. 1987 Jul;34(7):629-38. doi: 10.1016/0039-9140(87)80078-4.
The analytical capabilities of high power (2-4 kW) ICPs with argon as inner and intermediate gas and different outer gases (argon, nitrogen, oxygen and air) were studied under optimum and compromise operating conditions. Under the optimum conditions, the lowest detection limits for elements with sensitive atom lines (C, B, Zn) or ion lines (Mg, Mn, Fe, Cr, Ti, V) were achieved with argon as outer gas and an observation height of 13 mm. Under compromise conditions (3 kW, aerosol gas gauge-pressure 3 bar) the lowest detection limits for the atom lines were also found with a pure argon plasma at an observation height of 13 mm. For ion lines, however, the argon/oxygen and argon/nitrogen plasmas and an observation height of 8 mm were better. The detection limits were poorer in the presence of an aluminium matrix; under the optimum operating conditions, the relative increase in detection limit was smaller with the argon/oxygen and argon/air ICPs than with the pure argon or argon/nitrogen ICPs. It was found that the interferences arising from an easily ionizable matrix are lower with a diatomic gas than with argon as outer gas. The interferences when the argon/nitrogen, argon/oxygen and argon/air plasmas are used are similar and practically independent of the nebulizer-gas pressure applied.
研究了以氩气作为内气和中间气，并使用不同外气（氩气、氮气、氧气和空气）的高功率（2 - 4千瓦）电感耦合等离子体（ICP）在最佳和折衷操作条件下的分析能力。在最佳条件下，以氩气作为外气且观测高度为13毫米时，对于具有灵敏原子线（碳、硼、锌）或离子线（镁、锰、铁、铬、钛、钒）的元素可实现最低检测限。在折衷条件下（3千瓦，雾化气表压3巴），在观测高度为13毫米的纯氩等离子体中也发现了原子线的最低检测限。然而，对于离子线，氩气/氧气和氩气/氮气等离子体以及8毫米的观测高度效果更好。在存在铝基体的情况下检测限较差；在最佳操作条件下，氩气/氧气和氩气/空气ICP的检测限相对增加比纯氩或氩气/氮气ICP小。结果发现，与以氩气作为外气相比，使用双原子气体时，由易电离基体产生的干扰更低。使用氩气/氮气、氩气/氧气和氩气/空气等离子体时的干扰相似，并且实际上与所施加的雾化气压力无关。
