Vanadium K-edge x-ray absorption spectroscopy (XAS) was used to examine whole blood preparations from the tunicates Ascidia nigra and Ascidia ceratodes. Each XAS spectrum exhibits a rising edge inflection near 5480 eV characteristic of vanadium(III) and an intensity maximum at 5484.0 eV. In A. ceratodes blood cells, intrinsic aquo-VSO4+ complex ion is indicated by an inflection feature at 5476 ...

The ubiquity of vanadium oxo complexes in the V+ and IV+ oxidation states has contributed to a comprehensive understanding of their electronic structure and reactivity. However, despite being predicted to be stable by ligand-field theory, the isolation and characterization of a well-defined terminal mononuclear vanadium(III) oxo complex has remained elusive. We present the synthesis and charact...

Microorganisms can enzymatically reduce a variety of metals in metabolic processes that are not related to metal assimilation. Some microorganisms can conserve energy to support growth by coupling the oxidation of simple organic acids and alcohols, H2, or aromatic compounds to the reduction of Fe(III) or Mn(IV). This dissimilatory Fe(III) and Mn(IV) reduction influences the organic as well as t...

Giant magnetocaloric (GMC) materials constitute a requirement for near room temperature magnetic refrigeration. (Fe,Mn)$_2$(P,Si) is GMC compound with strong magnetoelastic coupling. The main hindrance towards application of this material comparably large hysteresis, which can be reduced by metal site substitution nonmagnetic element. However, the has two equally populated sites, tetrahedrally ...

A catalytic, enzyme-initiated (aza-) Achmatowicz reaction is presented. The involvement of a robust vanadium-dependent peroxidase from Curvularia inaequalis allows the simple use of H2O2 and catalytic amounts of bromide.

An enantioselective epoxidation of tryptophols followed by an intramolecular epoxide opening reaction was realized by chiral vanadium catalysts derived from C2 symmetric bis-hydroxamic acid (BHA) ligands. 3a-Hydroxyfuroindoline derivatives with up to 89% yield and 90% ee were obtained under mild reaction conditions.

fuel oil used in power plants contain metal impurities like vanadium. after combustion, this metal remains in boiler fuel ash in the form of oxide. in this research, extraction of vanadium oxide from fuel ash has been investigated. two processes were used for this purpose. a pyro- hydrometallurgy and a hydrometallurgy process. in the pyro-hydrometallurgy process, using sodium carbonate, salt ro...