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Abstract  

Line-broadening due to paramagnetic relaxation was observed in Mössbauer spectra of Eu2+ in glassy frozen solutions; such broadening may be used as an indicator of the state of dispersion of europium. It was demonstrated by the Mössbauer technique that Eu2+ was oxidized to Eu3+ by photoirradiation at >300 nm and that this oxidation reaction was induced by photoexcitation of the 320-nm band of Eu2+.

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Commission, Action plan for the deployment of intelligent transport systems in Europe, COM(2008)886 final, Brussels, 2008. The European Parliament and the Council of the European Union , Directive 2010/40/EU of the

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Journal of Radioanalytical and Nuclear Chemistry
Authors: D. Xu, Q. L. Ning, X. Zhou, C. L. Chen, X. L. Tan, A. D. Wu, and X. Wang

Summary  

Effects of ionic strength and of fulvic acid on the sorption of Eu(III) on alumina were investigated by using a batch technique. The experiments were carried out at T=25±1 °C, pH 4-6 and in the presence of 1M NaCl. The results indicate that sorption isotherms of Eu(III) are linear at low pH values. The sorption-desorption of Eu(III) on alumina at pH 4.4 is reversible, but a sorption-desorption hysteresis is found at pH 5.0. Fulvic acid has an obvious positive effect on the sorption of Eu(III) on alumina at low pH values. The migration of Eu(III) in alumina was studied by using column experiments and 152+154Eu(III) radiotracer at pH 3.8. For column experiments, Eu(III) sorbed on alumina can be desorbed completely from the solid surface at low pH values. The findings are relevant to the evaluation of lanthanide and actinide ions in the environment.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: Y. Suzuki, T. Nankawa, T. Yoshida, T. Ozaki, T. Ohnuki, A. J. Francis, S. Tsushima, Y. Enokida, and I. Yamamoto

Summary  

We have investigated the structure of Eu(III)-citrate complexes in aqueous solution and their degradability by Pseudomonas fluorescens. Analysis of 1:1, 1:2, and 1:5 Eu(III):citrate solutions at pH 7 by electrospray ionization mass spectrometry (ESI-MS) showed that the 2:2 Eu(III)-citrate complex is the predominant complex species at a low citrate/Eu(III) ratio, while at a high ratio, a 1:2 Eu(III)-citrate complex is formed preferably. Studies on the biodegradation of Eu(III)-citrate complex by P. fluorescens have shown that a 2:2 Eu(III)-citrate complex is resistent to degradation while a 1:2 complex transforms to a 2:2 complex with the degradation of excess citric acid.

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capita GDP. The methodology of the study is built on a panel regression analysis of EU countries. Based on the literature review, it was necessary to use more than one model to analyse the impact of spending on different areas on GDP-growth: ordinary

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HCOO) 3 ·2H 2 O (where Ln(III) = Pr, Er), Ln(CCl 3 COO) 3 ·2H 2 O (where Ln(III) = Pr, Nd, Eu, Dy, Yb), [Nd(CCl 2 HCOO) 6 (H 2 O) 3 ] n · m H 2 O and Nd x Ln 1− x (CCl 3 COO) 3 ·2H 2 O. In 2003 year [Tb 2 (CH 3 COO) 6 (H 2 O) 4 ]·4H 2 O and [Tb 2 (CF 3

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Introduction The Framework Programme (FP) is the main policy instrument of the European Union (EU) in the area of research and technological development. Introduced in the early 1980s to support European competitiveness in key

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. http://ec.europa.eu/eurostat/ statistics-explained/index.php/Population_and_social_conditions, accessed 02/04/2016. Friedland , D. – Richard , H. ( 2003 ): Underemployment

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Abstract  

The batch method and the column method were simultaneously employed to study the sorption and desorption of Eu(III) on red earth as a function of pH (4.6–6), the presence of a well-characterized fulvic acid (FA) and the iron oxides content of red earth. The results from both methods were consistent qualitatively. The Eu(III) sorption showed significant dependences on pH and FA, the sorption was increased with increasing pH and by addition of FA to the solutions, while the iron oxides content of the red earth had a negative contribution to the sorption of Eu(III). Additionally, the sorption-desorption hysteresis of Eu(III) on red earth occurred at a pH range of 4.6–6. Therefore, the humic substance and high pH have a great tendency to immobilize Eu(III) on red earth.

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Abstract  

The kinetics of homogeneous electron exchange Eu3+/Eu2+ has been investigated in 1M HClO4, water+dimethylformamide (DMF) mixed solvent by using labeled europium. Non-monotonic variations of the electron exchange rate constants as a function of the solvent composition was observed.

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