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.
Authors:Nashaat N. Nassar, Azfar Hassan, and Pedro Pereira-Almao
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
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
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.
Authors:Gurdip Singh, A. K. Shrimal, Inder Pal Singh Kapoor, Chandra Prakash Singh, Dinesh Kumar, and Manan S. Mudi
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
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
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.
Authors:Nahid Nishat, Sumaiya Hasnain, Tansir Ahmad, and Asma Parveen
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
Authors:Chun-Hong Jiang, Li-Fang Song, Cheng-Li Jiao, Jian Zhang, Li-Xian Sun, Fen Xu, Yong Du, and Zhong Cao
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