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A new Zn(II) mononuclear complex with tris(benzimidazol-2-yl-methyl)amine (NTB) was synthesized with stoichiometry of [Zn(NTB)NO3]NO3 · DIPY · DMF (DIPY : 4,4′-dipyridyl). The complex was characterized by elemental analysis, UV and IR spectra. The crystal structure was determined by using X-ray diffraction analysis. The crystal structure indicates that four N atoms and one O atom coordinate to zinc ion to construct a distorted trigonal-dipyramid configuration. Three nonprotonated N atoms from imidazole groups are in the equatorial plane, one alkylamino N atom and one O atom from NO3−- in the axial directions. The biological activity assay shows that this complex presents certain biological activity by means of pyrogallol autoxidation and it can be called a model compound of superoxide dismutase (SOD).

Effect of NaAc on the anodic growth of TiO2 nanotube arrays is described. NaAc-added approach yields longer nanotubes relative to samples grown from NaAc-free electrolyte. And the growth rate of TiO2 nanotubes has pH independency in NaAc-added electrolytes. The key to achieve a high aspect ratio TiO2 nanotube arrays is to decrease the chemical dissolution rate at the mouth of the tube by adding NaAc as protective coating. Adsorption of Ac- species on the TiO2 surface is shown to markedly decrease the chemical dissolution rate of the tube mouth, resulting in longer nanotube length.