Complexation of lanthanides, actinides and transition metal cations with a 6-(1,2,4-triazin-3-yl)-2,2’:6’,2’’-terpyridine ligand: implications for actinide(III) /lanthanide(III) partitioning

The quadridentate N-heterocyclic ligand 6-(5,5,8,8-tetramethyl-5,6,7,8-tetrahydro-1,2,4-benzotriazin-3-yl)-2,2’:6’,2’’-terpyridine (CyMe4-hemi-BTBP) has been synthesized and its interactions with Am(III), U(VI), Ln(III) and some transition metal cations have been evaluated by X-ray crystallographic analysis, Am(III)/Eu(III) solvent extraction experiments, UV absorption spectrophotometry, NMR studies and ESI-MS. Structures of the 1:1 complexes with Eu(III), Ce(III) and the linear uranyl (UO22+) ion were obtained by X-ray crystallographic analysis, and showed similar coordination behavior to related BTBP complexes. In methanol, the stability constants of the Ln(III) complexes are slightly lower than those of the analogous quadridentate bis-triazine BTBP ligands, while the stability constant for the Yb(III) complex is higher. 1H NMR titrations and ESI-MS with lanthanide nitrates showed that the ligand forms only 1:1 complexes with Eu(III), Ce(III) and Yb(III), while both 1:1 and 1:2 complexes were formed with La(III) and Y(III) in acetonitrile. A mixture of isomeric chiral 2:2 helical complexes was formed with Cu(I), with a slight preference (1.4:1) for a single directional isomer. In contrast, a 1:1 complex was observed with the larger Ag(I) ion. The ligand was unable to extract Am(III) or Eu(III) from nitric acid solutions into 1-octanol, except in the presence of a synergist at low acidity. The results show that the presence of two outer 1,2,4-triazine rings is required for the efficient extraction and separation of An(III) from Ln(III) by quadridentate N-donor ligand

Michel Schooyans, Destin du Brésil (coll. Sociologie nouvelle - Situations). 1973

Comblin J. Michel Schooyans, Destin du Brésil (coll. Sociologie nouvelle - Situations). 1973. In: Revue théologique de Louvain, 5ᵉ année, fasc. 4, 1974. pp. 502-503

Michel Schooyans, Destin du Brésil (coll. Sociologie nouvelle - Situations). 1973

Comblin J. Michel Schooyans, Destin du Brésil (coll. Sociologie nouvelle - Situations). 1973. In: Revue théologique de Louvain, 5ᵉ année, fasc. 4, 1974. pp. 502-503

OS MINISTÉRIOS NUMA SOCIEDADE EM VIA DE URBANIZÃO

O Concilio Vaticano II prescreve aos bispos no Decreto Christus Dominus, n. 16, § 5, o seguinte: "A fim de poderem cuidar do bem dos fins de maneira mais apropriada a condições de cada um, esforcem-se para conhecer-lhes a fundo as necessidades nas circunstâcias sociais em que vivem. Aproveitem, portanto, os instrumentos técnicos, especialmente, a pesquisa social"

J. Rojas - F. Vanderschueren, Chiesa e golpe chileno. La politica della Chiesa da Frei a Pinochet. Préface de Raniero La Valle. Appendice par l'évêque luthérien Helmut Frenz. 1976

Comblin J. J. Rojas - F. Vanderschueren, Chiesa e golpe chileno. La politica della Chiesa da Frei a Pinochet. Préface de Raniero La Valle. Appendice par l'évêque luthérien Helmut Frenz. 1976. In: Revue théologique de Louvain, 8ᵉ année, fasc. 1, 1977. pp. 92-93

J. Rojas - F. Vanderschueren, Chiesa e golpe chileno. La politica della Chiesa da Frei a Pinochet. Préface de Raniero La Valle. Appendice par l'évêque luthérien Helmut Frenz. 1976

Comblin J. J. Rojas - F. Vanderschueren, Chiesa e golpe chileno. La politica della Chiesa da Frei a Pinochet. Préface de Raniero La Valle. Appendice par l'évêque luthérien Helmut Frenz. 1976. In: Revue théologique de Louvain, 8ᵉ année, fasc. 1, 1977. pp. 92-93

Optics sequence management in PS complex

This note describes how optics definitions are handled by the Proton Synchrotron Complex control system. It presents the functionality of the software developed to support optics management. The optics are stored in LSA database and the associated table structure is outlined