Rapid, direct determination of strontium in natural waters by laser-induced breakdown spectroscopyстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 29 августа 2018 г.
Аннотация:We report a LIBS technique of Sr determination in different types of natural waters, which provides sufficient sensitivity for strontium quantifying in marine studies, and for the safety control of drinking waters. The technique provides rapid measurements, not longer than 1 min per sample, without any preconcentration or dilution of waters. We demonstrated that the ionic line Sr II 407.77 nm was preferable for strontium quantification in natural waters than atomic line Sr I 460.73 nm, since the ratio between them equaled to ~30. One of the obstacles is a variability of total content of salts in waters from 0.01% to 5%. We found that the salinity had a strong influence on electron density (Ne): Ne grew up dramatically in case of low salinity (0 to 100 mg L-1), and it did not change essentially for the salinity above 150 mg L-1. At the same time, plasma temperature (~1.1×104 K) was independent from salinity. Since an increase of salinity suppressed ionic signal of strontium, the addition of NaCl as an ionization buffer diminishes considerably the matrix effects on analytical results. LODs of Sr varied from 25 μg L-1 for pure or fresh waters to 200 μg L-1 for salty waters. We have shown that the suggested technique provided the accurate determination of strontium in samples of the Laptev Sea water and four types of mineral waters within the concentration range from 1 to 20 mg L-1.