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Abstract: Coordination polymers [Hg(L 2 )Cl2] n (1) and {[Hg2(L 2 )Cl4](DMF)} n (2) have been assembled from Hg(II) chloride and a novel tripyridyltriazole tecton 3,4-bis(2-pyridyl)-5-(4-pyridyl)-1,2,4-triazole (L 2 ) in different solvent media. Both complexes have been characterized by IR, microanalysis, powder X-ray diffraction, and thermogravimetric analysis. Single crystal X-ray diffraction indicates that the L 2 ligands take the (η3, μ2) and (η4, μ3) binding modes in 1 and 2, respectively, which connect the Hg(II) centers to afford linear and ladder-like 1D arrays. Interestingly, complex 1 exhibits strong solid state fluorescent emission at room temperature due to the intraligand transitions, whereas complex 2 is non-fluorescent. [ABSTRACT FROM AUTHOR]

Abstract: This work firstly presents detailed evidence of the fcc-type miscibility gap in the Cu–Ni–V system at temperatures between 1000°C and 1100°C. The phase equilibria, phase transformation behavior and microhardness of the (Cu0.5Ni0.5)100−xVx (at.%) (x=2, 4, 6, 8, 10, 12) alloys have been investigated by electron probe microanalysis, X-ray diffraction, differential scanning calorimetry and Vickers hardness tester, confirming that the fcc-type miscibility gap exists in the Cu–Ni–V system at temperatures between 1000°C and 1100°C. The obtained results will not only help to well understand the strengthening mechanisms in the Cu–Ni–V alloys at high temperatures, but also to effectively develop new high-temperature spinodal-hardened Cu–Ni–V base alloys in the future. [ABSTRACT FROM AUTHOR]

Abstract: The phase equilibria in the Co–W–V ternary system were experimentally investigated by optical microscopy (OM), electron probe microanalysis (EPMA) and X-ray diffraction (XRD) on the equilibrated alloys. Three isothermal sections of the Co–W–V ternary system at 1100°C, 1200°C and 1300°C were determined, and no ternary compound was found in this system. In addition, a novel phenomena induced by the liquid phase separation in the Co–W–V alloys was firstly discovered, suggesting that a stable liquid miscibility gap exists in the Co–W–V ternary system. The newly determined phase equilibria and firstly discovered phase separation phenomena in the Co–W–V system will provide important information for the development of Co–W based alloys. [Copyright &y& Elsevier]

The influence of Gd element and solution treatment on the microstructure of AZ31 alloy was investigated in this paper. The microstructure and phase composition were characterized by OM, SEM, EDS and XRD. The results indicate that Mg 17 Al 12 eutectic phase, scattered along the grain boundary, is suppressed effectively with Gd addition and the acicular Al 2 Gd superlattice with lamellar distribution is formed. Furthermore, the grain size of AZ31 alloy is also refined with Gd addition. In the subsequent process of solution, the migration and growth of Al 2 Gd phase conforms to Ostwald Ripening Theory. The morphology of Al 2 Gd phase becomes granular and scatterd in matrix uniformly after solution for 16 h at 813 K. [ABSTRACT FROM AUTHOR]

Abstract: Micrometer Li1.05Mn1.95O4 has been synthesized by solid state reactions with the nano-Mn3O4 as a precursor. X-ray diffraction, scanning electron microscopy and laser particle sizer are employed to investigate the structures, morphologies and particle size distributions of the powder. The micrometer Li1.05Mn1.95O4 exhibits good rate performance at room temperature with a specific capacity of 98.4mAhg−1 at 5C. The Li1.05Mn1.95O4/Li half cell also shows good cycling performance at elevated temperature with 90.5% of its initial capacity retained after 100 cycles at 1C. At −20°C, the Li1.05Mn1.95O4 delivers a stable cycling performance with a specific capacity of 84.5mAhg−1, being 84.1% of the capacity at room temperature. The cyclic voltammetry (CV) and rate performance measurements illustrate an increasing polarization with decreasing the temperature. In addition, the diffusion coefficients of lithium ions in Li1.05Mn1.95O4 at various temperatures (25, 0, −10 and −20°C) are determined to be in the magnitude of 10−10 to 10−12 cm2 s−1 by cyclic voltammetry (CV) method. [Copyright &y& Elsevier]