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Bismuth oxide/titania, one interfacial composite semiconductor with high photocatalytic activity under solar light, was prepared at low temperature. The structure was characterized by X-ray diffractometry (XRD), scanning electron microscopy (SEM), brunauer-emmett-teller (BET), X-ray photoelectron spectroscopy (XPS) and diffuse reflection spectra (DRS). The results indicate that deposited titania nanoparticles on bismuth oxide surface have micro-nano structure, and this composite material exhibits porosity and increased surface hydroxyl groups. Furthermore, the as-prepared photocatalyst shows higher photocatalytic activity to the degradation of 4-chlorophenol than pure titania or P25 under sunlight.

Dendrofullerene (C60DF) is a novel fullerene derivative with potential and promising biomedical applications. In this work, electrochemical/contact angle behavior of C60DF in the cellular system has been explored by in-situ electrochemical contact angle measurement. This measuring system is a newly developed technique which can provide electrochemical and contact angle detection simultaneously. The electrochemical results indicate that dendrofullerene may effectively bind and permeate the tumor cell membrane and then distribute into the cancer cells. Our observations of in-situ electrochemical contact angle measurement also illustrate that the permeation and interaction of C60DF with target cancer cells may lead to some variation of the configurational structure of the relative cell membrane and thus result in the change of hydrophilic/hydrophobic properties of target cellular system. Furthermore, through confocus fluorescence microscopy study we found that, upon application of C60DF, the intracellular accumulation of anticancer drug daunorubicin in leukemia K562 cells could be remarkably enhanced by C60DF. Therefore fullerene derivatives were demonstrated to be a good candidate that can play an important role in improving the intracellular drug uptake in the target cancer cells.

A novel molecular-based magnet of three-dimensional (3-D) cyanide-bridged bimetallic assembly, [[Ni(tn)2]5[FeII(CN)6]3]n(ClO4)n.2.5nH2O where tn = trimethylenediamine, was synthesized and structurally characterized. The compound with an asymmetric unit of C24H52.5Cl0.5Fe1.5N19Ni2.5O3.255 crystallized in the monoclinic system of the space group P2(1)/n with a = 10.173(3) A, b = 16.053(2) A, c = 26.309(3) A, beta = 91.30(2) degrees, and Z = 4. The assembly has a 3-D network structure extended by three different types of FeIII-CN-NiII-NC-FeIII linkages. The iron (FeIII) atoms are located in two different chemical environments, which were confirmed by Mössbauer experimental results. The nickel (NiII) atoms have three different coordination environments. Cryomagnetic properties revealed that 3-D magnetic ordering occurs over the lattice below the Curie temperature around 10 K.

The synthesis, crystal structure and magnetic properties of the imidazolate-bridged dinuclear copper(II) complex [LCu 2 (Im)(DMSO) 2 ](ClO 4 ) 3 (DMSO), where ImH is imidazole, and L is 3, 6, 9, 17, 20, 23-hexaazatricyclo[23.3.1.1 11,13 ]triaconta-1(29), 11(30), 12, 14, 25(26), 27-hexaene, have been studied. Single crystal X-ray diffraction determination reveals the distorted tetragonal pyramid geometries of the imidazolate bridged dicopper(II) center are incorporated within the binucleating macrocycle. Both copper atoms are five-coordinated by four basal nitrogen atoms (three from the macrocycle and one from the imidazolate) and one oxygen atom from the DMSO molecule. Two coordinated DMSO molecules are situated at the same side of the macrocycle. The Cu–Cu separation in the complex is 5.93 A. Magnetic measurements and ESR spectroscopy studies exibit an antiferromagnetic exchange interaction with a coupling constant of J = − 26.94 cm −1 . Investigations on the pH-dependent ESR of the title compound in frozen 50% aqueous DMSO solution confirm the existence of the bridged cation [LCu 2 (Im)] 3+ as a major species in solution mainly in the range 5.2⩽pH⩽11.5. The imidazolate bridge is broken in the pH range of 5.2–3.3, which is close to that for the native enzyme.

Three different metal ions doped TiO2 photocatalysts, which were prepared by the sol-gel method, were immobilized to porous nickel mesh by coating. The photocatalytic degradation activity of the supported photocatalyst on formaldehyde and volatile organic compounds (VOCs) was investigated. The results show that the nanometer TiO2 has an anatase structure. The photocatalytic degradation rate of formaldehyde and VOCs of 1.5% La3+ doped TiO2 coated on porous nickel mesh at 90 min are: 94% and 87%, higher than undoped TiO2: 83% and 72%, Fe3+ doped TiO2: 62% and 62%, Ag+ doped TiO2: 86% [Chinese character: see text] 81%. The orders of photocatalytic degradation rate on formaldehyde and VOCs with different content of La3+ doped TiO2 are as follows: 1.5%1%2%undoped, 1.5% is the optimum La3+ doped content. Decreasing circular wind speed and using 254 nm or 365 nm ultraviolet wavelength will not influence the photocatalytic degradation rate of formaldehyde and VOCs.

To identify and determine the congener and level of microcystins in the source water of Taihu Lake.Improved method of SPE combined with HPLC was employed to detect the concentration and varieties of microcystins in source water and bloom samples collected from Meiliang Bay, Taihu Lake.The contents of two predominant microcystin components, MC-RR, and MC-LR, were relatively high in samples during warm months and correlated with the phase of algae growth. The maximum concentrations of MC-RR and MC-LR in water sample reached 3.09 +/- 0.53 microg/L and 2.39 +/- 0.41 microg/L during the period of water bloom in September 2004, respectively. Even without waterbloom, the concentration of MC-LR in source water sample was still higher than the guideline value.The status of microcystin pollution in this region is serious and measures to monitor and control the growth of cyanobacteria are urgently needed.