No abstract available

[en] Ruthenium is one of a number of elements that complicates the regeneration of processed nuclear fuel from atomic power stations. Because of its chemical properties, it often acompanies various elements in the extraction process and thus complicates the purification of uranium. In this paper, we decided to investigate the extraction chemistry of nitrosoruthenium trinitrate in order to establish the solvate number and the establish the conditions under which this compound transfers into weakly extracted forms. This is important in controlling and improving the process of purifying uranium from ruthenium

[en] The preparation and reactions of substituted ruthenium carbonyl halides is described. The compounds occur as neutral, cationic or anionic complexes and in most cases the oxidation state of the ruthenium is 2+. The coordination numbers of four, five and six generally correspond to pseudo-tetrahedral, trigonal bipyramidal and octahedral geometries respectively. 274 refs.; 4 figs.; 9 tabs

[en] Published in summary form only

[en] The chemistry of the trinuclear clusters (Ru ₃ O (C H ₃ CO ₂) ₄ L ₃) where L = imidazole, pyridine or pyrazine type of ligands, was investigated based on spectroscopic and electrochemical techniques. These complexes are of great interest from the point of view of their electronic and redox properties, providing multi site species for electron transfer processes. They were isolated in solid state, and characterized by means of elementary analyses and infrared spectra. The electrochemical behaviour in acetonitrile solution was typically reversible; the cyclic voltamograms exhibited a series of four or five mono electronic waves ascribed to the successive Ru ^IV Ru ^III Ru ^III / Ru ^III Ru ^III Ru ^III/ ... Ru ^II Ru ^II Ru ^II redox couples. The differences between the successive redox potentials were about 1 V, indicating strong metal-metal interaction in the trinuclear Ru ₃ O centre. The E values were strongly sensitive to the nature of the N-heterocyclic ligand, increasing with the pi-acceptor properties of the pyridine and pyrazine derivatives, but in a much less pronounced way in the case of the imidazole derivatives. (author)

[en] To increase the limits of detection of ions Au, Ru and others in paper peak chromatography, their concentration is suggested on this very paper due to an increase of the analysed solution volume introduced on the paper. It is shown that deviation from the linear dependence of the peak heights on the determined ion concentration on the primary chromatograph near the limit of detection is explained by sorption of the ion with its precipitate. The concentration by two orders of magnitude enlargeds the concentration ranges of 1^- and Ru(3). The concentration is possible for small amounts of ions for which a nonlinear dependence occurs near the limit of detection

No abstract available

[en] Time-resolved absorption spectroscopy on the femtosecond time scale has been used to monitor the earliest events associated with excited-state relaxation in tris-(2,2'-bi-pyridine) ruthenium(II). The data reveal dynamics associated with the temporal evolution of the Franck-Condon state to the lowest energy excited state of this molecule. The process is essentially complete in ∼ 300 femtoseconds after the initial excitation. This result is discussed with regard to reformulating long-held notions about excited-state relaxation, as well as its implication for the importance of non-equilibrium excited-state processes in understanding and designing molecular-based electron transfer, artificial photosynthetic and photovoltaic assemblies in which compounds of this class are currently playing a key role. 24 refs., 2 figs

No abstract available

[en] Published in summary form only