Magnetically separable photocatalyst is a new photocatalyst,which has magnetic response characteristic.This composite photocatalyst not only has high photocatalytic activity,but also can be separated and recovered easily under the extrinsic magnetic field.Based on the findings reported in the present literatures,this paper introduced the naming and researching scope of magnetically separable photocatalysts and the inner structure of magnetic photocatalyst etc.Meanwhile,according to the combining modes of central core and outside shell layers,this paper focused on reviewing the research progress on magnetic materials of magnetically separable photocatalyst in recent years from two aspects,i.e.direct coating and un-direct coating.Finally,the present research hotspot and development trend of magnetic photocatalysts were put forward.

Functionalized carbon nanotubes containing sulfonic groups can improve the chemical property of nanotube, and may promote their many potential applications such as in composites and coatings. A facile method to prepare functionalized carbon nanotubes containing highly reactive sulfonic groups on its surface via the reaction between sodium dodecyl sulfate and carboxylated carbon nanotubes is described. Ultraviolet absorbance intensity analysis and transmission electron microscope confirmed that the functionalized multi-walled carbon nanotubes can be individually dispersed and retain a long uniform state in water. Fourier transformed-infrared spectroscopy showed that reactive sulfonic groups were covalently attached to carbon nanotubes. The zeta potentials of the colloid solution of functionalized multi-walled carbon nanotubes decrease to less than -32 mV under all studied pH values,which indicate that they are stable in water according to the theory of colloid stabilization.

After being refluxed with concentrated nitric acid for different time at 120 degrees C, the multi-walled carbon nanotubes (MWNTs) were modified with sodium dodecyl sulfate (SDS). The MWNTs were characterized with TEM and IR. in addition, UV-vis spectrophometric measurement was used to quantitatively characterize colloidal stability of the dispersion. It's found that the carbon nanotubes refluxed for 4 h had a uniform length with many hydroxyl groups and carboxyl groups on the surface. Experimental results show that the addition of SDS could significantly improve the dispersion of MWNTs in water, and after 80 h, the concentration decreased very slowly to 90% of its originality.

采用机械合金化和热压烧结制备了Ti3Al/TiC+ZrO2复合材料。研究了不同烧结温度（1500,1550℃）及Ti3Al在TiC基体中不同的添加方式对烧结体力学性能的影响,并对烧结体的断口进行了SEM分析。结果表明:在Ti3Al和ZrO2协同增韧补强的作用下,得到的烧结体具有良好的力学性能,其断裂以穿晶和沿晶相结合方式进行,并且出现了内晶。

A multi-walled carbon nanotube(MWNT)/hydroxyapatite(HA)composite was made by using an in situ synthesis method and characterized by various techniques.Fourier transformed-infrared results show that there are some anionic groups on the surface of the MWNTs after being refluxed with nitric acid,which form an efficient matrix for the growth of HA crystals.An X-ray diffraction study shows that the proper pH value is the key factor for obtaining HA crystals.Transmission electron microscope images suggest that the HA nucleated and crystallized on the surface of the functionalized MWNT at pH=10,and they also indicate that the size of the HA is a function of the aging temperature.

Ti_3Al/TiC+ZrO_2 composites were prepared by mechanical alloying and hot-press sintering. The effects of different sintering temperatures (1500, 1550℃) and addition modes of Ti_3Al to TiC matrix on the mechanical properties and microstructure were studied, and the fracture surfaces were analyzed with SEM. The results show that the composites have excellent properties with cooperating effects of Ti_3Al and ZrO_2. Intergranular cracking, transgranular cracking and some intragranular grains are all presented on the fracture morphology.

Dense Fe3Al/CNT composite with CNT content of 5vol.% has been fabricated by spark plasma sintering (SPS) that retains the integrity of CNT in the matrix. Samples were synthesized at pressure of 30MPa, and temperature of 1273K. Their structures were studies using X-ray diffraction; transmission electron microscope (TEM). The composites have very promising mechanical properties: microhardness of 8.7GPa and compressive yield strength of 3175MPa, about 95% and 56% increment over monolithic Fe3Al which was fabricated under the same process. It is indicated that CNTs are regarded as an effective nanoscale reinforcement for the intermetallics matrix composites. This makes the composite an attractive advanced material for future applications.

碳纳米管优异的力学性能以及纳米级尺寸,与工程材料复合可起到强化作用.采用碳纳米管作为增强相来改善氧化铝陶瓷材料的脆性成为一个重要的研究领域.本文综述了碳纳米管-氧化铝陶瓷复合材料的制备工艺,碳纳米管-氧化铝陶瓷复合材料的强韧化效果及机理,以及当前研究的焦点和存在的问题,材料的界面结合以及外场力传递效应是值得关注的课题,并对该领域工作做了一些讨论和展望.

The iron aluminides Fe3Al have been among the widely studied intermetallics because of its exceptional properties, it's widely applications are related closely with the correspondence strengthening technique advance. Micro-alloying is considered as an important for improving the total mechanical properties. From the view of physics, it is significant for grasp the micro-alloying to develop the new material. The influence of micro-alloying elementals on mechanical properties, as well as strengthening mechanism is reviewed.