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In this paper, Epoxy/Al2O3 and Epoxy/WC-Co coating were obtained on TC18 titanium alloy by air spraying process. The effect of adding nano filler Al2O3 and WC-Co ceramic particle in the epoxy resin coating on dry sliding at ambient temperature has been investigated. It was found that the addition of Al2O3 and WC-Co particles could improve the hardness of epoxy coating while maintaining the toughness of the substrate, which is one of the reasons for the improvement of wear resistance. The results of wear test showed that the friction coefficients of Epoxy/Al2O3 and Epoxy/WC-Co coating were 0.72–0.73 and 0.62, slightly higher than that of the TC18 alloy substrate. However, the specific wear rates of the Epoxy/Al2O3 and Epoxy/WC-Co coating were greatly reduced and the wear resistance was improved. Compared with the TC18 titanium alloy substrate, the wear resistance of Epoxy/Al2O3 coating increased by 64.7%–69% after adding ceramic particles, which was slightly higher than that of Epoxy/WC-Co coating by 59.4%–62%. The excellent wear resistance of the Epoxy/Al2O3 can be attributed to its high resistance to plastic deformation and nano effect of Al2O3 particles. The wear mechanism of TC18 titanium alloy was mainly abrasive wear, while Epoxy/Al2O3 and Epoxy/WC-Co coatings were adhesive wear.

Ce3+-substituted Sr-ferrite powder was synthesized through low-temperature calcination ceramic method. The influence of Ce3+ substitution on the microstructure and magnetic properties of Sr-ferrite powder was discussed. Results showed that the Ce3+ ions could completely enter the ferrite lattice when the substitution amount was in the range of x = 0–0.2. The saturation magnetization and intrinsic coercivity of Sr1−xCexFe12O19 ferrites could be enhanced through Ce3+ substitution. These enhancements were attributed to the improvements in the magnetic structure and microstructure.

Ca2+ doped SrLa-ferrite powder was synthesized through molten salt assisted method. The influence of Ca2+ doping on the microstructure and magnetic properties of SrLa-ferrite poweder was discussed. The results showed that non-agglomerated Sr0.7-xCaxLa0.3Fe12O19 ferrite powder with narrow particle size distribution could be synthesized by molten salt assisted calcination process. This powder exhibited excellent magnetic properties after eliminating the impurity phase through Ca2+ doping.

High activated graphitic carbon nitride (g-C3N4) was initially produced by a typical calcination of melamine, and then modified by a convenient successive activation: protonated in hydrothermal hydrochloric acid (g-C3N4-1) and subsequently immersed in aqueous sodium hydroxide solution (g-C3N4-2). Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermogravimetry were used to characterise the morphology, crystal structure and thermal stability of the as-prepared samples. The SEM and TEM showed that g-C3N4-2 had a much smaller aggregate size than g-C3N4-1 and obviously displayed porous structures. The XRD patterns indicated the decrease of inter-lamellar spacing between the layers of samples and the increase of stretched properties of g-C3N4-2. Under visible-light irradiation, the modified g-C3N4 showed higher photocatalytic activity for degradation of rhodamine B solution than pristine samples due to the tiny particles aggregate and porous structure. Thus, the method of acid and alkali treatment will widen the photocatalysis and application of g-C3N4.

Ca2+ doped Sr0.45-xCaxLa0.55Fe11.6Co0.4O19 (x = 0, 0.15, 0.3, and 0.45) ferrites were fabricated through a conventional ceramic process. The influences of Ca2+ doping on the microstructure and magnetic properties of ferrites were investigated. Ca2+ doping could mitigate the presence of impurity phase (CoFe2O4) in ferrites. Single phase M-type ferrites could be fabricated when x ≥ 0.3. Additional Co2+ ions entered the crystal lattice and preferentially occupied the 4f2 site with Ca2+ doping. This effect greatly improved the remanence (Br) and intrinsic coercivity (Hcj) when x increased from 0 to 0.3. The average grain size of sintered ferrites slightly increased with the amount of doped Ca2+ ions. This behavior led to the deterioration of Hcj when x increased from 0.3 to 0.45. Consequently, ferrite prepared with x = 0.3 presented the highest maximum energy product ((BH)max) of 5.24MGOe. This performance is much higher than that of conventional La-Co substituted Sr-ferrites.

The hardness and Young'modulus for two Cu-based bulk metallic glasses, Cu59Zr36Ti5 and Cu61Zr34Ti5, has been studied by nanoindentation in three different ways, including load rate control mode, load control mode, and cycles load control mode. Young's modulus of the specimen shows the dependence on loading rate when the loading rate is no more than 5 mN/s. The Young's modulus of both Cu59Zr36Ti5 and Cu61Zr34Ti5 decreases with the increasing of holding load and loading rate. But neither loading rate nor holding load has significant influence on hardness. Cyclic loading leads to slight hardening for Cu59Zr36Ti5, while Cu61Zr34Ti5 doesn't show such results. What's more, Cu61Zr34Ti5 exhibits obviously higher hardness and modulus than Cu59Zr36Ti5.

Au-Pt alloy nanoparticles that are selectively anchored on TiO2 surface of the ellipsoidal zirconium titanium composite oxides were successfully prepared by a facile two-step method: prefabricated binary composite oxides on the ellipsoidal Fe2O3@SiO2 by a versatile cooperative template-directed coating method, and then in situ formation of Au-Pt alloy NPs with Sn2+ as the reduction agent. The alloy catalysts were characterized by X-ray diffraction, transmission electron microscopy and X-ray photoelectron spectroscopy. The result suggested that highly dispersive and ultrafine Au-Pt alloy nanoparticles were deposited onto TiO2 surface of the binary oxides solely. The particle size of nanoalloys was closely related to the ratio of Zr: Ti in the composite oxides shell. Increasing the content of Zr element led to a growth in the size of alloy nanoparticles. When used as catalysts for the reduction of 4-nitrophenol, the prepared supported alloyed catalysts exhibited high catalytic activity, and the sample could be easily recycled without a significant decrease of the catalytic activity.