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In this experiment, the spinel-type lithium manganese oxide (LiMn2O4) prepared via solid-phase sintering method was coated with magnesium titanium composite oxide (MgTiOx) in the presence of polyvinyl pyrrolidone (PVP) under the ultrasonic wave. The crystal structures, surface morphologies and electrochemical properties of the sample prepared were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and electrochemical analysis. The X-ray diffractions indicated that the LiMn2O4 coated with MgTiOx were similar to that of the pure LiMn2O4, and they both showed sharp and high peaks. The particles of the samples prepared with PVP did not aggregate obviously, and the samples were coated completely and homogeneously. At charge-discharge rates of 0.2C, the first discharge capacity can reach more than 120 mAh / g. Compared with pure LiMn2O4, the capacity attenuation of MgTiOx-coated LiMn2O4 reduced after fifty cycles, and showed good electrochemical performance.

As a conductive fillers, graphite nanosheets can be induced by the AC electric field in unsaturated polyester resin and then prepared oriented unsaturated polyester resin/graphite nanosheets composite. We investigate the preparation, configuration and capability of the unsaturated resin/ graphite nanosheets conductive composites and the oriented theory of the graphite nanosheets induced in the electric field. The measures and observation of scanning electron microscopy(SEM), X-ray diffraction(XRD), electric current have shown that the graphite nanosheets are oriented by electric field which were randomly dispersed in the polymer matrix at the beginning, and then oriented with their flakes along the electric field in the polyester resin.

As conductive fillers, graphite nanosheets can be induced by the AC electric field in unsaturated polyester resin and then prepared oriented unsaturated polyester resin/graphite nanosheets composite. we investigate the preparation、configuration and capability of the unsaturated resin/graphite nanosheets conductive composites and the oriented theory of the graphite nanosheets induced in the electric field. The measures and observation of scanning electron microscopy (SEM), X-ray diffraction (XRD), electric current have shown that the graphite nanosheets are oriented by electric field which were randomly dispersed in the polymer matrix at the beginning, and then oriented with their flakes along the electric field in the polyester resin.

TiC/C composite fibers were prepared by vapor phase titanizing of the regular carbon fibers via chemical vapor deposition (CVD). The carbon fibers were titanized from the surface of the fiber to the core. Scanning electron microscope (SEM) and X-ray diffraction (XRD) were applied to characterize the morphology and structure of the TiC/C composite fibers. The influences of CVD reaction conditions such as temperature and reaction time on the TiC particle size and the thickness of the deposited layer were investigated. Higher temperature and longer time resulted in the growth of bigger size of the TiC crystal particles, and the particle uniformity was also decreased.

Unsaturated polyester resin/Graphite nanosheet composites were prepared using in situ polymerization under AC electric field which was applied during composite curing to induce orientation of graphite nanosheets. Scanning electron microscopy (SEM) has been applied to demonstrate the orientation of graphite nanosheets As a result, the percolation threshold was decreased to 0.25 wt% due to the orientation of the graphite nanosheets.

Graphite nanosheets (GNs) prepared by sonicating expanded graphite were homogeneously dispersed in unsaturated polyester resin using sonication. The dispersion with a curing agent was then subjected to a dc electric field, followed by crosslinking, to fabricate a polymer/GN composite film. Scanning electron microscopy revealed that the GNs in the film were oriented parallel to the electric field. UV-VIS measurements indicated that the optical properties of the field-induced composite film showed significant improvement in visible light transmittance compared with those prepared without the electric field.

Magnesium hydroxide (Mg(OH)2) particles were synthesized and modified via a reaction-hydrothermal process in the present of NaOH. The resultant magnesium hydroxide was characterized by X-ray powder diffraction (XRD), field-emission scanning electron microscopy (SEM) and BET specific surface area. It was found that NaOH played a key role in the morphology and dispersion Mg(OH)2 particles.

TiC/C composite fibers were prepared by vapor phase titanizing of the regular carbon fibers via chemical vapor deposition (CVD). The carbon fibers were titanized from the surface of the fiber to the core. Scanning electron microscope (SEM) and X-ray diffraction (XRD) were applied to characterize the morphology and structure of the TiC/C composite fibers. The influences of CVD reaction conditions such as temperature and reaction time on the TiC particle size and the thickness of the deposited layer were investigated. Higher temperature and longer time resulted in the growth of bigger size of the TiC crystal particles, and the particle uniformity was also decreased.

Zn-Al-Mg alloy coating attracted much attention due to its high corrosion resistance properties, especially high anti-corrosion performance at the cut edge. As the Zn-Al-Mg alloy coating was usually produced by hot-dip galvanizing method, solidification process was considered to influence its microstructure and corrosion properties. In this work, a Zn-Al-Mg cast alloy was melted and cooled to room temperature with different solidification processes, including water quench, air cooling and furnace cooling. Microstructure of the alloy with different solidification processes was characterized by scanning electron microscopy (SEM). Result shows that the microstructure of the Zn-Al-Mg alloy are strongly influenced by solidification process. With increasing solidification rate, more Al is remained in the primary crystal. Electrochemical analysis indicates that with lowering solidification rate, the corrosion current density of the Zn-Al-Mg alloy decreases, which means higher corrosion resistance.