P. Pakalns

TL;DR: In this paper, a comprehensive investigation of the spcctrophotometric determination of aluminium with chrome azurol S is described, and a molar absorptivity of 21,500 at 567.5 mμ was found for the aluminium-chrome azurols S lake, with a relative standard deviation of ± 0.4% at the 20 μg Al level.

TL;DR: Uranium can be separated from fresh waters on Chelex-100 resin by careful control of the resin pH at 4.9-4.7 after addition of 1,2-diaminocyclohexanetetraacetic acid.

TL;DR: In this article, the same authors show that the total metal present in natural waters is not adsorbed by Chelex-100 unless metal ions are first released from colloids or strong complexes, and that low recoveries can be attributed to incomplete metal elution rather than to blockage of adsorption sites.

TL;DR: In this article, a general method for the spectrophotometric determination of phosphorus at trace levels is presented, which involves extraction of the yellow molybdophosphoric acid with isobutyl acetate and subsequent reduction to heteropoly blue.

TL;DR: In this paper, a general method for the spectrophotometric determination of silicon at trace levels is presented, which involves the extraction of the yellow silicomolybdate with isoamyl alcohol and subsequent reduction to silicomeric blue.