Study on copper complexing ligand concentrations in several China's coastal waters

Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regularity and the relationship with other parameters were discussed. The results were as follows： Copper complexing ligand concentrations of the South China Sea were a little higher than those of other sea areas, and they were apparently higher than those of the ocean. Compared with the subsurface layer （SSL） in the sea surface microlayer copper complexing ligand concentrations showed an enrichment phenomenon, of which the mechanism is similar to dissolved organic matter. The metal complexing ligand concentration profiles of the South China Sea showed that the value in the sea surface was the highest, then it decreased with depth accruing, and a higher value appeared at the bottom. Copper complex- ing ligand concentrations were higher than those of cadmium and lead. Ligands in each sea area exhibited a complicated property. In short, the distribution regularity of copper complexing ligand concentrations in China＇s coastal waters was consistent with that of other regions in the world. Meanwhile, the positive relationship between the copper complexing ligand concentrations and biological oxygen demand, chemical oxygen demand, dissolved organic carbon, and viscosity were found clearly.

Determination of copper complexation in surface microlayer of Daya Bay and Jiaozhou Bay

Copper complexing ligands concentration (C C) and conditional stability constant of the sea surface microlayer (SML) and subsurface layer (SSL) samples, collected from Daya Bay of Guangdong Province and Jiaozhou Bay of Shandong Province, were determined by anodic stripping voltammetry (ASV) technique. C C of Daya Bay in the SML ranged from 6.19×10-7 to 3.52×10-7 mol/L. C C of Jiaozhou Bay in the SML ranged from 5.30×10-7 to 3.03×10-7 mol/L in August 1998 and from 3.46×10-7 to 1.36×10-7 mol/L in May 2000. The C C concentrations were higher in all surface microlayer samples, compared with corresponding subsurface samples. The average enrichment factors of copper complexation in the SML observed above were 1.58, 1.41 and 1.56, respectively. The enrichment of C C concentration in the microlayer demonstrated that organic ligands had certain buffer action on the toxicity of the enriched trace metals in the same layer. Conditional stability constants of the SML in Jiaozhou Bay were lower than those of the SSL; however, it showed just opposite for Daya Bay. BOD (biological oxygen demand) and COD (chemical oxygen demand) indicated the organic matter content, also showed enriched in the SML. C C had an obvious relationship with BOD or COD.

Synthesis and Structural Characterization of a Copper Complex with Furaldehyde Salicylylhydrazone

The copper complex Cu（C12H9N2O3）2 has been synthesized by the reaction of furaldehyde salicylylhydrazone （Hfs） and copper acetylacetonate and characterized by X-ray crystal diffraction and spectroscopic studies. The crystal crystallizes in space group P211n with a = 5.9765（3）, b = 15.7196（9）, c = 12.0514（6）A,β= 101.618（3）^o, V = 1109.0（1）A^3, C24H18CuN4O6, Mr = 521.96, Z = 2, Dc = 1.563 g/cm^3, μ = 1.035 mm^-1, F（000） = 534, R = 0.0373 and wR = 0.1058 for 2283 observed reflections （I 〉 2σ（I））. The copper atom has a square-planar CuN2O2 coordination and should be in an octahedral coordination if considering Cu-O （phenol） with distances of 2.796（2）A as weak bonds. The neighboring copper complex molecules are linked together by these weak Cu-O （phenol） bonds, resulting in an extended 1D chain. The title compound exhibits paramagnetic property and fluorescence behavior at room temperature supported by the EPR and fluorescence spectra.

X-ray Crystal Structure of a Mononuclear Copper (Ⅱ) Complex with Unusual Monodentate O-coordination of Carboxylate Group of Isonicotinate

Reaction of Cu(ClO4)2'6H2O with tripodal ligand tri s (2-benzi nd dazol yl methyl ) aInine(ntb) and sodium isonicotinate (Iso) yielded a mononuclear complex lCu(ntb)(lso)]ClO4.3.5H2O. Thestructure has been established by X-ray crystallography The Cu (Ⅱ) atom is in a distorted trigonalbipyranddal environment with three benzimindazole N atoms of ntb defining the equatorial plane, oneandne N atom of ntb, and one O atom of the carboxylate group of isonicotinate occupying the axialpositions.