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. However, there are seldom reports about the effect of Te on the catalytic performance of heteropolycompound catalysts for partial oxidation of isobutane [ 15 , 16 ]. It has been reported that molybdenum-based heteropolyacids with Keggin structure

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The medical significance essential biological metals zinc, copper and molybdenum and their nutritional and biochemical significance are rewied.

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The chemical effects of98Mo(n, )99 Mo reaction on molybdenum(II) chloride [(Mo6Cl8)Cl4] have been studied. Retention, thermal and radiolytical annealing were determined. It was found that this molybdenum compound has low retention, a negligible tendency to thermal annealing and a virtual insensitivity to hydrolysis. For practical application in the enrichment of99Mo by the Shilard-Chalmers method, molybdenum(II) chloride [(Mo6Cl8)Cl4] appears to offer good prospects.

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preparation of the pigments and also to determine the influence of growing content of molybdenum, the calcination temperatures and also method of preparation on their colour properties after application into organic matrix and in some cases into a ceramic

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A radiochemical procedure for the consecutive separation of vanadium and molybdenum, copper, manganese, rubidium and potassium is proposed for the analysis of biological materials. Vanadium and molybdenum are extracted together with 0.1% BPHA solution in toluene, copper followed by manganese are extracted as diethyldithio-carbamate complexes with chloroform and rubidium and potassium are precipitated as tetraphenylborates.

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Molybdenite is the main ore mineral for the molybdenum industry and the production of molybdenum. The industrial processing of molybdenite is based on its oxidized roasting to technical grade molybdenum oxide, followed by its purification by distillation or its ammonia leaching.The present work reports a thermal analysis study of the oxidized roasting of Egyptian molybdenite, using a derivatograph. The reaction products were identified microscopically and by using a Siemens Crystalloflex diffractometer.The DTA curves of the roasting of molybdenite show that its oxidation begins at 360–370°C, as indicated by the small exothermic peak at such temperatures. This is followed immediately by a large, wide exothermic peak with maximum at 510–520°C, representing the intensive oxidation of molybdenite. The medium endothermic peak at 795–800°C reflects the melting and sublimation of molybdenum oxide. The vigourous vaporization of molybdenum oxide and its boiling are associated with the large, sharp endothermic peak at 1150°C. This is accompanied by a large loss in mass (TG).The study includes calculation of the thermodynamic constants and the kinetics of the reaction of oxidation of molybdenite.The oxidized roasting of molybdenite results in the production of molybdenum oxide, which is the essential starting material of the molybdenum industry. The molybdenum oxide produced has the molybdite structure and crystallizes in the orthorhombic system in the form of elongated, thin, light-green crystals.

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., Shinmachi, F., Mcgrath, S.P., Abecassis, J., Hawkesford, M.J., Shewry, P.R. 2010. Impacts of sulphur nutrition on selenium and molybdenum concentrations in wheat grain. J. Cereal Sci. 52 : 111–113. Shewry P

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Technetium-99m, separated from fission molybdenum-99, has been studied as a component of liquid-liquid phase distribution equilibria. 5-(4-Pyridyl)nonane in a carrier diluent, benzene, has been used to study the distribution of the nuclide from thermodynamically suitable aqueous phases of electrolytes with and without sterically receptive thiocyanate ions. Efficient extraction of the metal can be accomplished in a variety of aqueous phase compositions. The separation factors with respect to molybdenum, under certain experimental conditions, are fairly high. The data have been utilized to effect clean separations of technetium from molybdenum.

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Introduction The heteropoly compounds containing molybdenum together with vanadium as Keggin polyanion-[PV x Mo 12− x O 40 ] −(3+ x ) (noted PVMo) are very interesting for catalysis due to their simultaneous acidic and redox

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Molybdenum-99 is produced in large quantities as the parent radioisotopes of99mTc, which has been used recently in nuclear medicine. The neutron capture reaction on molybdenum and the nuclear fission of uranium are used for the large scale production of99Mo. The products by these methods are used properly according to the objects of diagnosis. In this paper, the production of99Mo is reviewed and the development of the production in JAERI is outlined.

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