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C19H20O8, triclinic, P 1 ‾ $P\overline{1}$ (no. 2), a = 7.0708(4) Å, b = 8.1261(4) Å, c = 16.1067(6) Å, α = 81.252(4)°, β = 81.500(4)°, γ = 77.890(4)°, V = 887.88(8) Å3, Z = 2, R gt (F) = 0.0418, wR ref(F 2) = 0.1158, T = 150 K.

A novel and high efficient PbO2 electrode has been fabricated in the present study for refractory wastewater treatment. The traditional Ti plate is made into honeycomb by electronic corrosion to be used as electrode basement. The novel surface topography improves the specific surface area of the electrode material and enhances the adhesion of surface coating. SnO2-Sb layer is deposited between basement and PbO2 layer which reduces the thermal stress and improve electrode life. Rare earth element La is doping into PbO2 layer to improve the lattice structure and the catalytic performance. Finally, F ion is adding into the catalytic layer to improve the smoothness of the material surface. Characterized by SEM and XRD, results showed that the electrode prepared has novel surface morphology. Pollutants degradation results and electrode life test showed that the PbO2 electrode investigated in the present study has great advantage compared with traditional electrodes and has good application prospect.

The automotive emission has become the main source of the air pollution in cities. How to remove NOx effectively is the key and difficult point in the control of automobile exhaust. In this work, sol-gel was applied to prepare NOx purification catalyst, LaCoO3 which was doped with strontium (Sr) and iron (Fe). The average particle size was less than 25 nm. The optimum composition of doped LaCoO3 was determined as La0.8Sr0.2Co0.95Fe0.05O3 with a minimum particle size, 14.3nm. The denitrification rate of La0.8Sr0.2Co0.95Fe0.05O3 increased by 27.9% compared with that of LaCoO3. It was noted that the sample powder would agglomerate when doped LaCoO3 was calcinated at 800°C, the calcination temperature of LaCoO3. Therefore the calcination temperature for double doped LaCoO3 was optimized. According to results of XRD and BET, the optimum calcination temperature of La0.8Sr0.2Co0.95Fe0.05O3 is 575°C, which not only overcame the agglomeration but also reduced the particle size to 11.2nm. The denitrification rate of La0.8Sr0.2Co0.95Fe0.05O3 calcinated at 575°C is up to 95.8% which is higher 38.7% than that of it calcinated at 800 °C.

A major challenge in chemical engineering is the separation and purification of materials, especially of rare earth compounds. It has been reported that a dielectrophoretic (DEP) apparatus can be used for separating rare earth oxides. The DEP capture of REOs on screen electrode was observed with microscope. The concentration of ROEs was determined using a nephelometer and ICP-OES before and after injection into the DEP apparatus. The results show that three types of REOs, La2O3, CeO2 and Dy2O3, generate nDEP in the DEP capture apparatus. There are two factors: voltage and suspension concentration, that affect the capture rate. The capture rate increases as voltage rises within certain limits. The capture rate also increases with increase in the original suspension concentration. Different REOs show marked differences in the DEP capture conditions. Consequently, factors such as voltage and flow rate can be controlled to achieve separation of different REOs.

Hydrogen zeolite was modified with CeO2 by impregnation - filtration - heat treatment. Hydrogen-zeolite samples before and after modification were characterized by XRD and SEM. The catalytic efficiency of modified hydrogen-zeolite was investigated. Such modification conditions were explored: as the CeO2 percentage, calcination temperature, calcination time, impregnation temperature. The results show that the optimal CeO2 percentage is 0.5%, calcination temperature is 600°C, calcination time is 2h, impregnation temperature is 75°C. The aspirin yield reaches 78.3% under the optimal conditions, compared with that (64.8%) catalyzed by sulfuric acid and that (70.4%) catalyzed by unmodified zeolite. XRD, SEM characterizations show that Ce ions can be doped into the zeolite framework. And the modification makes the zeolite particle size become smaller, which is reduced to 50.5nm from 56.76nm. A high efficient and eco-enviromently catalyst was got by modification.

In the present study, catalyst of SO42-/ZrO2-TiO2-SiO2-Al2O3 has been prepared by sol-gel method and doped by Y, La and Chitosan, respectively. The catalytic ability of modified catalysts for the synthesis of hexyl butyrate has been tested. It has been shown that the catalytic ability has been improved obviously after modification. Under the best experimental conditions, with Y doping 1%, La doped 1.5% and Chitosan doped 4%, the catalytic ability has been improved from 76.7% to 90.7%, 92.1% and 93.9%. Characterized by XRD, SEM and IR, it has been found that the grain sizes of catalysts are smaller which due to higher specific surface andimprove the catalytic ability. With abundant amino groups at the surface, the Chitosan doping improves the capacity of SO42- for catalysts.

One lanthanide nitrate (Ln = Tb) with a novel three dimensional structure have been prepared through hydrothermal method. Single crystal X-ray diffraction structures were obtained. The compound crystallizes in the orthorhombic,Pnmaspace group. The lanthanide ions are eight-coordinate with six oxygen atoms coming from nitrate ions and two from bridge oxygen atoms. If the bridge oxygen atoms could be ignored, the compound can be described as a rare microporous 3D Lanthanide nitride with the open framework.

To obtain efficient non-viral vectors, a series of Gemini cationic lipids with carbamate linkers between headgroups and hydrophobic tails were synthesized. They have the hydrocarbon chains of 12, 14, 16 and 18 carbon atoms as tails, designated as G12, G14, G16 and G18, respectively. These Gemini cationic lipids were prepared into cationic liposomes for the study of the physicochemical properties and gene delivery. The DNA-bonding ability of these Gemini cationic liposomes was much better than their mono-head counterparts (designated as M12, M14, M16 and M18, respectively). In the same series of liposomes, the bonding ability declined with an increase in the tail length. They were tested for their gene-transferring capabilities in Hep-2 and A549 cells. They showed a higher transfection efficiency than their mono-head counterparts and were comparable or superior in transfection efficiency and cytotoxicity to the commercial liposomes, DOTAP and Lipofectamine 2000. Our results convincingly demonstrate that the gene-transferring capabilities of these cationic lipids depended on the hydrocarbon chain length. Gene transfection efficiency was maximal at a chain length of 14, as G14 can silence about 80% of luciferase in A549 cells. Cell uptake results indicate that Gemini lipid delivery systems could be internalised by cells very efficiently. Thus, the Gemini cationic lipids could be used as synthetic non-viral gene delivery carriers for further studies.