Vanadium belongs to the group of transition metals and is present in the air and soil contaminants in large urban agglomerations due to combustion of fossil fuels. It forms numerous inorganic compounds (vanadyl sulfate, sodium metavanadate, sodium orthovanadate, vanadium pentoxide) as well as complexes with organic compounds (BMOV, BEOV, METVAN). Depending on the research model, vanadium compou...

Some ascidians (sea squirts) accumulate the transitional metal vanadium in their blood cells at concentrations of up to 350 mM, about 10(7) times its concentration found in seawater. There are approximately 10 different types of blood cell in ascidians. The identity of the true vanadium-containing blood cell (vanadocyte) is controversial and little is known about the subcellular distribution of...

Sol-gel process with continuous ultrasonication was used to produce pure and vanadium doped titania powders. The amount of in varied by using different initial concentrations solutions. Scanning electron microscopy particle size analyses showed formation spherical shaped particles diameter ranging from 3 11 nm. average pore volume 0.0248 cm³/g, the surface areas V-doped were 62.9 66.1 m2/g, res...

A series of vanadia catalysts supported on SBA-15 (V/SBA) with a vanadia (V) content ranging from 1% to 11% were prepared by an incipient wetness method. Their catalytic behavior in the dehydrogenation of isobutane to isobutene with CO2 was examined. The catalysts were characterized by N2 adsorption, X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and temperatur...

Vanadyl sulfate and sodium orthovanadate in the concentration range between 5 and 50 microM are shown to be mitogenic for quiescent cultures of Swiss mouse 3T3 and 3T6 cells. The compounds caused a striking shift in the dose-response for the effect of serum on [3H]thymidine incorporation and DNA synthesis. In the absence of serum the effect of vanadium was greatly potentiated by insulin. Vanadi...

Vanadium, V, is a redox-sensitive metal that in solution, under aerobic conditions, prevails as the oxyanion vanadate(V). There is little known regarding vanadium toxicity to soil biota, and the present study was set up to determine the toxicity of added vanadate to soil organisms and to investigate the relationship between toxicity and vanadium sorption in soils. Five soils with contrasting pr...

The catalytic activity of oxide-supported vanadium oxide is improved by the presence of tungsten oxide for the selective catalytic reduction of nitric oxides. We propose a mechanism for V−W synergy through studies of the reduction−oxidation behavior of near-monolayer VOX and WOX species grown by atomic layer deposition on the α-Al2O3 (0001) single crystal surface. In situ X-ray standing wave me...

Two preparation methods (wet saturation impregnation with vanadyl acetylacetonate and ball-milling of γ-Al2O3 with crystalline V2O5) were applied to produce two sets of VOx/γ-Al2O3 catalysts with increasing vanadium loadings. Materials from both sets were characterized by XRD, SEM, Raman, TPR and UV/Vis-DRS to elucidate the influence of the preparation method on the morphology of VOx species an...

A series of vanadium(III) complexes bearing monodentate tertiary phosphine ligands of the type VCl3(PRnPh3-n)2 (n = 0 (1a); n = 1 and R = Me (1b), Et (1c), iPr (1d), Cy (1e); n = 2 and R = Me (1f), Et (1g), Cy (1h)), and VCl3(PR3)2 (R = Cyp (2a), Cy (2b), nPr (2c), tBu (2d)) were synthesized and characterized. In the case of 1c, 1g and 2a single crystals were also obtained and their molecular s...

The tridentate ligand 2,6-bis(3,5-diphenylpyrazol-1-ylmethyl)pyridine, abbreviated as 2,6-[(3,5-ph₂pz-CH₂)₂-py], a new pyridine-pyrazole derivative, was prepared from 2,6-bis(bromomethyl)pyridine and 3,5-diphenylpyrazole. The ligand was characterized by means of elemental analyses, ATR-IR, ¹H- and ¹³C-NMR spectroscopy and single crystal X-ray crystallography. Using this ligand, a new mononuclea...