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Updated: Aug 29, 2026

In Situ Measurement of Vacuum Window Birefringence using 25Mg+ Fluorescence
Published on: June 13, 2020
[Schiff base type onno spectrophotometric determination of magnesium]
Gladiola Tântaru1, Nela Bibire, V Dorneanu
1Disciplina Chimie analitică şi Analiză instrumentală, Facultatea de Farmacie, Universitatea de Medicină şi Farmacie Gr.T. Popa Iaşi.
Abstract:
By condensing hydrazide salicylic acid with o-hydroxy carbonilic compounds it was obtained 2--hydroxy acetophenon--salicyl hidrazina, Schiff base--type ONNO. These Schiff bis bases present a good capacity of complexing the Mg (II) ions. The above mentioned Schiff base forms complex with Mg (II) cation, with maximum absorbance at 386 nm, and molar absorbtivity (epsilon) = 6.27 x 10(4) mol-1.L.cm-1. The complex with Mg (II) presents a maximum stability at pH = 9.6 - 10.0. The calculated apparent stability constant is K = 3.18 x 10(3). The absorbance is proportional to Mg (II) concentration in the range of 10-60 mg/mL. In this range, the Lambert--Beer law is respected, the linearity coefficient being 0.9818, SD = 0.83, RSD = 0.84 (n = 6). The results obtained for spectrophotometric determination of Mg (II) using this Schiff base as reagent were successfully applied to pharmaceutical products containing Mg (II) cation.
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