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Em cám ơn anh nhiều ạ.

Nhờ anh down giúp em mấy bài báo trên trang Science Direct:
1. Simultaneous determination of propacetamol and paracetamol by derivative spectrophotometry
2. Simultaneous determination of Sb(III) and Sb(V) by partial least squares regression
3.Simultaneous spectrofluorimetric determination of (acetyl)salicylic acid, codeine and pyridoxine in pharmaceutical preparations using partial least-squares multivariate calibration
4. Simultaneous determination of methylxanthines in coffees and teas by UV-Vis spectrophotometry and partial least squares
5.Simultaneous determination of antimony(III) and antimony(V) by UV–vis spectroscopy and partial least squares method (PLS)
6.Simultaneous spectrophotometric determination of chromium(VI) and iron(III) with chromogenic mixed reagents by H-point standard addition method and partial least squares regression
7.Simultaneous determination of Fe(II) and Fe(III) in pharmaceutical formulations with chromogenic mixed reagent by using principal component artificial neural network and multivariate calibration
8. Simultaneous determination of Zn(II), Cd(II) and Hg(II) in water