The chemical interactions between thorium(IV) and O2- in the LiF-BeF2 (2 : 1 mol%) (FLiBe) LiF-NaF-KF (46.5 11.5 42 (FLiNaK) molten salt systems were studied at 873 K. precipitation-dissolution behavior of Th(IV) oxide/oxyfluoride species, as well speciation law these species their relationship with oxide concentration fluoride melts, clarified. results showed that FLiBe melt would only produce...

Mn(1.5)Co(1.5)O(4) spinel oxide as a cathode or one component of a composite cathode presents no visible reaction with an Y(2)O(3)-stabilized ZrO(2) electrolyte. The low electrode polarization resistances and good performance compared with traditional Sr-doped LaMnO(3)-YSZ composite cathodes imply promising application for the next generation of intermediate-temperature solid oxide fuel cells.

Co-Mn oxide nanosheets with the chemical composition H0.23Co0.23Mn0.77O₂ (C23M77NS) and MnO₂ nanosheets (M100NS) were prepared by exfoliation of layer-structured oxides via chemical processing in an aqueous medium. The optical properties of C23M77NS and M100NS were compared using UV-Vis spectroscopy, and the valence states of Mn and Co and local structures around them were examined using X-ray ...

Escherichia coli growing anaerobically respond to NO, with a 3-fold induction of the iron-containing superoxide dismutase. Mutants lacking nitrate reductase do not show this response. Anaerobically grown cells also contain an inactive form of the manganesecontaining superoxide dismutase (MnSOD) which can be activated by addition of Mn(I1) salts in the presence of acidic guanidinium chloride, fo...

Field measurements in the Arcachon Bay (south-west France) indicated anaerobic production of NOx via nitrification which was coupled to the reduction of Mn-oxides. To provide evidence for the occurrence of this process, laboratory microcosm experiments were set up. A N tracer based approach was used to track if NOx produced through Mn-oxide mediated anaerobic nitrification would be reduced to N...

The structure and electrochemical characteristics of composites based on multi-walled carbon nanotubes (MWCNTs) manganese oxide with the addition rhenium has been studied. It shown that decorating MWCNT surface layers or nanoparticles (Mn(III) + Mn(IV)) provides more than a twofold increase in value specific capacitance at low potential scan rates. However, only exhibit poor behavior decreases ...

Manganese (Mn) oxides are among the most reactive natural minerals and play an important role in elemental cycling in oceanic and terrestrial environments. A large portion of naturally-occurring Mn oxides tend to be poorly-crystalline and/or nanocrystalline, with not fully resolved crystal structures. In this study, the crystal structures of their synthetic analogs including acid birnessite (Ac...

A series of magnetically active ferrite nanoparticles (NPs) are prepared by using Mn oxide NPs as seeds. A Verwey transition is identified in Fe3O4 NPs with an average diameter of 14.5 nm at 96 K, where a sharp drop of magnetic susceptibility occurs. In MnFe2O4 NPs, a spin glass-like state is observed with the decrease in magnetization below the blocking temperature due to the disordered spins ...

Accelerated precipitation of Mn-rich rocks in the early Paleoproterozoic ocean is considered to reflect irreversible rise oxygen atmosphere during Great Oxidation Event (GOE), 2.501–2.220 billion years ago. But conditions, pathways, mechanisms, and linkages redox, broadly remain unresolved. The Lagoa do Riacho Mn deposit Borborema Province, northeastern Brazil, Ceará state, consists mainly mang...

Microbes exert extensive control on redox element cycles. They participate directly or indirectly in the concentration and fractionation of elements by influencing the partitioning between soluble and insoluble species. Putative microbially mediated manganese (Mn) oxides of the birnessite-type, enriched in rare earth elements (REE) + yttrium (Y) were recently found in the Ytterby mine, Sweden. ...