Nickel metavanadate

Nickel Metavanadate, Ni(V03)2, separates as greenish-yellow, transparent prisms when a solution of ammonium metavanadate is boiled with excess of nickel nitrate solution feebly acidified with nitric acid.1... 

Nickel Polyvanadates.—Ni0.2V20B.8H20 is obtained as greenish-brown crystals from the mother-liquor left after crystallisation of nickel metavanadate. The compound 8Ni0.5V205.24H20 has been prepared in two crystalline forms.7... 

At a pH near 6, manganese(II) metavanadate precipitates and does not react further, whereas at a pH near 2, other heteropoly species are formed. Inasmuch as commercial potassium metavanadate is not suitable for the syntheses of the 13-vanadomanganate(IV) and nickelate(IV), directions for the preparation of this compound are included in the syntheses below, which are modified from the method of Flynn and Pope.5 The preparation of the yellow-tinged green reduced form of potassium 13-vanadomanganate(IV) is also included.5... 

Cohen M, Klein C, Costa M (1992) Forward mutations and DNA-protein crosslinks induced by ammonium metavanadate in cultured cells. Mutat Res 269 141-148 Connett PH, Wetterhahn KE (1983) Metabolism of the carcinogenic chromate by cellular constituents. Struct Bond 54 93-124 Conway K, Costa M (1989) Nonrandom chromosomal alterations in nickel-transformed Chinese hamster embryo cells. Cancer Res 49 6032-6038... 

Both potassium nitrate (0.5%) and potassium chromate (0.2%) are very effective in carbon dioxide systems, but not with hydrogen sulfide. Use of metavanadate in hot carbonate systems can passivate steel in a carbonate solution only when the bicarbonate content is low. The addition of oxygen to the system increases passivation of mUd steel, but increases corrosion of copper-nickel alloys. 

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