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A flow injection on-line preconcentration system coupled to an electrothermal atomic absorption spectrometer for the determination of trace metals in saline media is described, The filterless, magnetic collection of coprecipitated analytes is based on the tetrahydroborate reductive precipitation of added iron and palladium in alkaline medium at a sample flow rate of 1.7 ml min(-1), The precipitate is dissolved in a 20 mu l volume of mixed acid and transported direct to the graphite furnace, Withthe exception of Cr (33% recovery in seawater), recoveries of Ag, As, Bi, Cd, Co, Cu, Mn, Ni, Pb, Sb and Tl averaged 84% from deionized water and 67% from coastal seawater with a frequency of 12 measurements h(-1), The sensitivity of the graphite furnace technique can be enhanced over 400-fold (for an 11 ml sample volume) compared to a standard 20 mu l injection volume, Detection limits in the low pg (absolute) or pg ml(-1) (relative) range can be reached, Results, presented for the determination of As, Cd, Cr, Cu, Mn and Ni in 1 ml volumes of CASS-3 NRCC Certified Reference Material seawater, are not statistically different (t-test, 95% confidence limit) from the certified values for these elements. 建立了流动注射在线富集系统的电热耦合的盐水中的微量金属决心媒体原子吸收光谱仪介绍，该滤波器，磁收集沉淀分析物的氢化是在碱性介质中还原沉淀补充铁和钯的在一分钟的一点七毫升（-1），采样流速，溶解的沉淀是在一个20亩的混合酸升运数量和直接向石墨炉，Withthe除铬（33％海水回收），银回收率，砷，铋，镉，钴，铜，锰，镍，铅，锑，铊从沿海海水平均为12测量小时（-1），对石墨炉灵敏度频率去离子水84％和67％技术可提高400倍（为11 ml样品量）标准相比，20亩升注射量，在低页码检测限（绝对）或PG毫升（-1）（相对）范围内可以达成，结果，对作为决定提出，镉，铬，铜，锰，镍量在1毫升中国社会科学院- 3共和党国会委员会认证的参考材料海水，没有统计学差异（t检验，95％的信心限制从标准值）这些元素。 |
