Search Results

You are looking at 31 - 40 of 4,141 items for :

  • All content x
Clear All

Introduction Association of a metal ion with an organic ligand through a chemical bond, changes drastically the properties of ligand and metal. It stabilizes the system and changes the solubility and reactivity. Metal complexes

Restricted access

Abstract  

We introduce the effective Lagrangian with spontaneously broken density in the Sethna-Sachdev-Nelson formula, and propose one explanation for the increase of the positron diffusion lengthL + in the liquid metal phase with temperature. It is shown that the effective mass of the positron in the liquid metal phase will decrease due to the restoration of the spontaneously broken density around the positron, when temperature increases.

Restricted access

additions on heavy metal availability in light textured soils: implications for crop yields and metal uptakes. Environ. Pollut. , 121 , 413–423. Shepherd M. A. Effects of past

Restricted access

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.

Restricted access

Adriano, D. C., 1986. Trace Element in the Terrestrial Environment. Springer-Verlag. New York. Alapi, K. & Győri, Z., 2003. Investigations on mud on heavy metal

Restricted access

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.

Restricted access
Interventional Medicine and Applied Science
Authors: Alexey Tymoshenko, Gennadii Tkach, Vitalii Sikora, Valentina Bumeister, Ihor Shpetnyi, Mykola Lyndin, Olena Maksymova, and Anna Maslenko

effect on all biological species [1] . Direct or indirect intake of different contaminants can cause a disease or become a reason for the development of related disorders [2, 3] . Heavy metals are considered to be terribly dangerous for their

Open access

azolidene carbenes to function as ligands in transition-metal complexes is well-established [ 10 , 11 ]. Consequently, biologically relevant molecules containing azoles are candidates as carbine sources for metal complexation. We consider the utilization of

Restricted access

172 287 291 García-Domínguez, M., Lopez-Maury, L., Florencio, F. J., Reyes, J. C. (2000) A gene cluster involved in metal homeostasis in the

Restricted access

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

Restricted access