Retraction notice to "Effects of organic ligands on fractionation of rare earth elements (REEs) in hydroponic plants: An application to the determination of binding capacities by humic acid for modeling" [Chemosphere 65(11) (2006) 1942-1948].

Reason: This article has been retracted, please see Elsevier Policy on Article Withdrawal:http://www.elsevier.com/locate/withdrawalpolicy This article has been retracted at the request of the editor as the authors have plagiarized part of papers that had already appeared in Chem.

Fractionations of rare earth elements in plants and their conceptive model.

Fractionations of rare earth elements (REEs) and their mechanisms in soybean were studied through application of exogenous mixed REEs under hydroponic conditions. Significant enrichment of middle REEs (MREEs) and heavy REEs (HREEs) was observed in plant roots and leaves respectively, with slight fractionation between light REEs (LREEs) and HREEs in stems. Moreover, the tetrad effect was observed in these organs.

Effects of organic ligands on fractionation of rare earth elements (REEs) in hydroponic plants: an application to the determination of binding capacities by humic acid for modeling.

Previous studies have revealed the fractionation processes of rare earth elements (REEs) in hydroponic plants, with a heavy REE (HREE, the elements from Gd to Lu) enrichment in leaves. In this study, effects on the HREE enrichment in soybean leaves with additions of carboxylic acids (acetate, malate, citrate, NTA, EDTA and DTPA) and two soil humic acids (HAs) were investigated. REE speciation in carboxylic acid and HA solutions was simulated using Visual MINTEQ and Model V, respectively.

[Influence of PO4(3-) and citrate on REE accumulation and fractionation in wheat].

This paper has studied the influence of phosphate (Pi, one of inorganic ligands) and citrate (Cit, one of organic ligands) on accumulation and fractionation of REEs in wheat based on aqueous culture, added with extraneous mixed REEs (MRE) and ICP-MS analysis technology. The results show that initial phosphate (Pi) solution of different levels followed by exposure to fixed-MRE solution has no significant effects on accumulation of the total concentrations of REEs (sigma REE) in the wheat roots, but it decrease the REE dramatically in the wheat leaves. Simultaneous culture of wheat with mixture of MRE and citrate solution caused obvious decreases of the sigma REE both in wheat roots and leaves.

Role of ligands in accumulation and fractionation of rare Earth elements in plants: examples of phosphate and citrate.

Few studies have been carried out on the effects of ligands on rare earth element (REE) bioaccumulation processes. In this study, the effects of phosphate (Pi, an inorganic ligand) and citrate (an organic ligand) on accumulation and fractionation of REEs in wheat were investigated using aqueous culture with extraneous mixed REEs (MRE). The results show that initial Pi solution culture at various levels followed by exposure to a fixed-MRE solution did not significantly change the total concentrations of REEs (SigmaREE) in roots, whereas the SigmaREE in leaves dramatically decreased with increasing levels of Pi applied.

Accumulation and fractionation of rare earth elements (REEs) in wheat: controlled by phosphate precipitation, cell wall absorption and solution complexation.

Previous studies on rare earth element (REE) bioaccumulation have focused on their accumulation rate and fractionation, but the processes involved remain unclear. In this study, the accumulation and fractionation of REEs in wheat (Triticum aestivum L.) were investigated using solution culture with exogenous mixed REEs.