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Abstract  

An experiment demonstrated the possibility of developing a zone refining process that would produce the first plutonium metal of extremely high purity. Plutonium rods containing known amounts of impurities were melted inside tantalum boats and passed horizontally through a three-turn, high-frequency coil so as to cause a narrow molten zone to pass through each rod 10 times. The impurity elements cobalt, chromium, iron, nickel, neptunium, and uranium moved in the same direction as the molten zone, as predicted; the elements aluminum, americium, and gallium moved in the opposite direction of the molten zone, as predicted. As the impure alloy was zone refined, δ-phase plutonium metal crystals formed.

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effect of nanoparticles toward asphaltene cracking has to be determined. Our previous studies have provided information on the catalytic effect of transition metal oxide nanoparticles toward asphaltene gasification and oxidation [ 2 , 6 , 7 , 12

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Abstract  

Hydrazinium metal ethylenediaminetetraacetate complexes of molecular formula (N2H5)2[Mg(edta)·H2O], (N2H5)3[Mn(edta)··H2O](NO3)·H2O, N2H5[Fe(edta)·H2O], N2H5[Cu(Hedta)·H2O] and N2H5[Cd(Hedta)·H2O]·H2O have been synthesized and characterized by elemental and chemical analysis, conductivity and magnetic measurements and spectroscopic techniques. The thermal behaviour of these complexes has been studied by thermogravimetry and differential thermal analysis. The data set provided by the simultaneous TG-DTA curves of the complexes shows the occurrence of three or four consecutive steps such as dehydration, ligand pyrolysis and formation of metal oxides. X-ray powder diffraction patterns of copper and cadmium complexes show that they are not isomorphous. These studies suggest seven coordination for Mg,Mn, Fe complexes and six coordination for Cu and Cd derivatives.

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. [20] F.D. Snell , Photometric and Fluorometric Methods of Analysis of Metals , Part I, Interscience , New York, NY , 1978 , p. 08

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Journal of Thermal Analysis and Calorimetry
Authors: Gurdip Singh, A. K. Shrimal, Inder Pal Singh Kapoor, Chandra Prakash Singh, Dinesh Kumar, and Manan S. Mudi

Introduction Metal nitrate and perchlorate complexes fall in the category of energetic metal complexes because of the presence of reducing and oxidizing group in the same molecule. Now a day, keen interest has been increased to

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Journal of Thermal Analysis and Calorimetry
Authors: Luiz K. C. de Souza, Juliana J. R. Pardauil, José R. Zamian, Geraldo N. da Rocha Filho, and Carlos E. F. da Costa

), trivalent (Al, Ga, Cr, Fe, Ce, La), and tetravalent (Ti, V, Mn, Sn, Zr) transition and non-transition metal ions in the silica network with the objective to increase catalysis activity because Si-MCM-41 shows low catalysis activity due to its weak acid

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Abstract  

Ferrites have been used to separate a wide range of substances such as dissolved metal species, particulate matter, and organic and biological materials; they have been used almost exclusively for metal waste treatment applications. However, ferrites can be used to remove and concentrate selected trace metals in a wide variety of feed solutions requiring analysis. A brief overview of ferrite properties and recent applications for trace metal recovery and concentration will be presented.

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Abstract  

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

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Introduction In the recent years, the synthesis of new polymers with unusual thermal, optical, and mechanical properties has gradually gained regards. The branch of the polymer–metal complexes has been developed as an

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polycarboxylates as linkers. This new emerging class of hybrid materials called metal–organic frameworks (MOF) may potentially find many applications in the field of gas storage [ 1 – 6 ], separation [ 7 – 10 ], catalysis [ 11 , 12 ], and luminescence [ 13 – 16

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