The removal of color and chemical oxygen demand (COD) from simulated dye wastewater containing Acid Orange II was experimentally investigated using coagulation-electrooxidation. Two kinds of coagulation methods, ferrous-mediated coagulation and electrocoagulation were tested as pretreatment. The electrooxidation was carried out in a cell with a three-phase three-dimensional electrode using granular activated carbon as particle electrodes. Particular attention was paid to probe the effect of cell voltage, airflow rate, solution conductivity and treatment time on the electrochemical treatment efficiency. The experimental results showed that the coagulation-electrooxidation process could efficiently remove the color and the COD from the simulated dye wastewater. The overall COD and color removal efficiencies reached as high as 99% and 87%, respectively, by ferrous coagulation (molar rate of Fe(II)/dye: 0.5) and 30-min electrolysis (cell voltage: 20.0V and airflow: 0.1m3 h-1).

A platinised TiO2/ITO film, Pt-TiO2/ITO, was prepared by a dip-coating and subsequent photodeposition procedure. Compared with bare TiO2/ITO film, Pt-TiO2/ITO film not only possesses a relative high photocatalytic activity but also shows a rather non-photocatalytic activity towards HCOOH degradation at room temperature and atmosphere pressure. The non-photocatalytic effect of platinised TiO2 was partly responsible for degradation of formic acid in the photocatalytic process. The non-photocatalytic activity of Pt-TiO2/ITO film is very dependent on its preparation method.

A dimethoate-degrading enzyme from Aspergillus niger ZHY256 was purified to homogeneity with a specific activity of 227.6 U/mg of protein. The molecular mass of the purified enzyme was estimated to be 66 kDa by gel filtration and 67 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point was found to be 5.4, and the enzyme activity was optimal at 50℃ and pH 7.0. The activity was inhibited by most of the metal ions and reagents, while it was induced by Cu21. The Michaelis constant (Km) and Vmax for dimethoate were 1.25 mM and 292 mmol min21 mg of protein21, respectively.

The aim of this paper is to report the recent laboratory work on the synthesis of novel Ru(Ⅱ) polypyridine complexes and the studies of their interaction with DNA. The first part describes the syntheses and crystal structures of several novel polypyridine ligands containing imidazole or Schiff base moiety and their Ru(Ⅱ) complexes. The second part focuses on the influences of the shape, size and substitute groups of intercalative ligands and co-ligands on the binding modes, intensities and enantioselectivities of the complexes to DNA. The interactions of Ru(Ⅱ) complexes to different native DNAs are also compared. Certain regularity between the selection of a particular binding mode and the structure of complexes and:or DNA was observed. The final part of the paper reports the preliminary studies on a new DNA-mediated luminescence quenching assembly. The experimental results seem to support the notion that the p-stacked bases of DNA polymer maybe offer a pathway for electron transfer.

2-(2-Chlorophenyl)imidazo[4,5-f ]1,10-phenanthroline (CIP) or 2-(2-nitrophenyl)imidazo[4,5-f ]1,10-phenanthroline (NIP) and their complexes [Ru(bpy)2(CIP)]21 and [Ru(bpy)2(NIP)]21 (bpy=2,29-bipyridine) have been synthesized and characterized. The binding of the two complexes to calf thymus DNA has been investigated with spectrophotometric methods and viscosity measurements. The experimental results indicate that the two complexes bind to DNA through a partial intercalative mode that is different from the bonding mode for their parent compound, [Ru(bpy)2(PIP)]21 (PIP=2-phenylimidazo[4, 5-f ]1, 10-phenanthroline). The crystal structure of [Ru(bpy)2(CIP)]-[ClO4]2?2H2O was determined by X-ray diffraction analysis; the imidazo[4, 5-f ]1, 10-phenanthroline moiety is not coplanar with the 2-chlorophenyl ring, having a dihedral angle of 44.58 in the CIP.