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In recent years, as a novel photocatalyst with the excellent ability to absorb visible light, BiVO4 has drawn increasing attention. In this paper, the photocatalytic mechanism and the electronic band structure of BiVO4 were introduced in detail. On the basis of main modifications of BiVO4, progress in BiVO4 photocatalyst for degradation was further reviewed. The aim of this work is to provide guideline for the intensive studies of BiVO4 in future.

In this paper, the synthesis methods of silver nanowires including template, self-assembled, hydrothermal synthesis and polyol methods are reviewed. In addition, the application and development of the silver nanowires are introduced.

Erosion wear is an important failure mode existing in hydropowder, petroleum, chemical industry and other fields. Nanostructured WC-Co materials possess excellent erosion wear resistance due to their outstanding combination of high hardness and excellent fracture toughness. Nanostructured WC-12Co coating was prepared by means of High Velocity Oxygen Fuel (HVOF) spraying technology in this research. The simulating experiment system was developed to study the erosion wear properties. The corundum sand with main composition of Al2O3 was used to investigate the dynamic erosion properties of nanostructured WC-12Co coating. The dynamic failure mechanism of the coatings was also analyzed by Scanning Electron Microscope (SEM). The results show that the coating is worn layer by layer in the erosion test. The bonding between the layers and the thickness of the coating should be increased to elongate the coating life.

In this paper, WC-12Co coating are prepared by two HVOF systems. The biggest difference between these two systems is the fuel gas use. Morphology and mechanical properties of the coatings are analyzed. The results show that the coating sprayed with Airplane Kerosene fuel gas is denser and the WC particles distribute more even than that sprayed with propane fuel gas. And the WC particles melt more fully. The hardness, Young’s Modules and fracture toughness of the coating sprayed with Airplane Kerosene fuel gas is higher than that sprayed with propane fuel gas.

YAG:Ce phosphors were synthesized by co-precipitation method. The photoluminescence intensity of samples sintered by the two-step route increases by about 10%, and with 0.5 wt.% NH4Cl added as flux, surface morphologies and size distribution are improved. The white LEDs were fabricated using as-obtained phosphors. It shows natural white light with chromaticity coordinates of (0.3083, 0.3163), color temperature (Tc) of 6886 K, the average CRI of 75, and the luminous efficacy of 85 ml/W. Therefore, The as-obtained YAG:Ce phosphors could be regard to have potential application in white LED devices.

In this paper, LaNi4.7Al0.3 alloy samples were obtained via melting in middle frequency influence fire .In addition, The alloy pellets were milled for absorbing and desorbing Hydrogen ability study, The P-V-T measurement provided us with poisonous effect on the oxidation of LaNi4.7Al0.3.To understand the poisoning mechanism of O2 on LaNi4.7Al0.3, the X-ray photoelectron spectroscopy (XPS) was introduced to analyzed the process of poisoning of LaNi4.7Al0.3 alloy, Which revealed the changes of the valence of the elements of the alloy LaNi4.7Al0.3 poisoned by O2.

CeO2@SiO2 (core@shell) nanoparticles were prepared by means of chemical precipitation technique. Results from X-ray diffraction, transmission electron microscopy (TEM), and Zeta-potential analyses provide strong microscopic and spectroscopic evidences to prove that CeO2 particles have been encapsulated inside amorphous SiO2 shell. As revealed from TEM investigations, the average grain size of CeO2@SiO2 is significantly smaller than that of uncoated CeO2 nanoparticles prepared under the same conditions, indicating it is an effective method to restrict the grain enlargement of nanocrystalline CeO2 by coating a thin layer of SiO2 at elevated temperatures. The CeO2@SiO2 nanoparticles display a similar surface electric character behavior to that of SiO2, and its dispersibility in water is improved.

In this work, a new kind of biodegradable pH-sensitive hydrogel was successfully synthesized by UV-initiated free radical polymerization. The obtained hydrogel was characterized by (1)H NMR and FTIR. Swelling behavior in different aqueous media and pH responsivity of the hydrogels were studied in detail as well. With increase in pH from 1.2 to 7.2, swelling ratio of the hydrogel increased. The morphology was observed by scanning electron microscopy, and the hydrolytic degradation behavior was also investigated in this work.

A series of low molecular weight poly(ethylene glycol)–polycaprolactone–poly(ethylene glycol) (PEG–PCL–PEG) biodegradable block copolymers were successfully synthesized using isophorone diisocyanate (IPDI) as the coupling agent, and were characterized using 1H NMR and Fourier transform infrared spectroscopy. The aqueous solutions of the PEG–PCL–PEG copolymers displayed a special thermosensitive gel–sol transition when the concentration was above the corresponding critical gel concentration. Gel–sol phase diagrams were recorded using the test-tube-inversion method; they depended on the hydrophilic/hydrophobic balance in the macromolecular structure, as well as some other factors, including the heating history, volume, and the ageing time of the copolymer aqueous solutions and dissolution temperature of the copolymers. As a result, the gel–sol transition temperature range could be altered, which might be very useful for application in injectable drug delivery systems.

A series of biodegradable PCL-PEG-PCL block copolymers were successfully synthesized by ring-opening polymerization of epsilon-caprolactone initiated by poly(ethylene glycol) (PEG), which were characterized by (1)H NMR, (13)C NMR, and FTIR. Their aqueous solution displayed special gel-sol transition behavior with temperature increasing from 4 to 100 degrees C, when the polymer concentration was above corresponding critical gel concentration (CGC). The gel-sol phase diagram was recorded using test tube inverting method and DSC method, which depended not only on chemical composition of copolymers, but also on heating history of copolymer's aqueous solution. As a result, the gel-sol transition temperature could be adjusted, which might be very useful for its application in biomedical fields such as injectable drug delivery system. And the typical shell-core structure of PCL-PEG-PCL micelles was introduced. The micelle-packing and partial crystallization might be the key gelation machanism for this gel-sol transition behavior of PCL-PEG-PCL aqueous solution.

The effects of annealing process on the electrical conductivity and mechanical properties of Cu-Te alloys were studied via AG-10TA electronic universal machine, SB2230 digital electric bridge, SEM and EDS. The results show that recrystallization and precipitation occur simultaneously during the annealing process of Cu-Te alloys. Tellurium precipitates as Cu2Te second phase. The grain size increases with the increasing of annealing temperature and time. The electrical conductivity increases monotonously. The tensile strength of Cu-Te alloy is higher than that of pure copper.

Quantitatively evaluation of antibacterial activities of inorganic antibacterial agents is an urgent problem to be solved. Using experimental data by an orthogonal design, a prediction model of the relation between conditions of preparing inorganic antibacterial agents and their antibacterial activities has been developed. This is accomplished by introducing BP artificial neural networks in the study of inorganic antibacterial agents. It provides a theoretical support for the development and research on inorganic antibacterial agents.

In this article, nano-magnetite particles (ferrofluid, Fe3O4) were prepared by chemical co-deposition method. A series of biodegradable triblock poly(epsilon-caprolactone)-poly(ethylene glycol)-poly(epsilon-caprolactone) (PCL-PEG-PCL, PCEC) copolymers were synthesized by ring-opening polymerization method from epsilon-caprolactone (epsilon-CL) initiated by poly(ethylene glycol) diol (PEG) using stannous octoate as catalyst. And the magnetic PCEC composite microspheres were prepared by solvent diffusion method. The properties of the ferrofluid, PCEC copolymer, and magnetic PCEC microspheres were studied in detail by SEM, VSM, XRD, Malvern Laser Particle Sizer, 1H-NMR, GPC, and TG/DTG. Effects of macromolecular weight and concentration of polymer, and the time for ultrasound dispersion on properties of magnetic microspheres were also investigated. The obtained magnetic PCEC microspheres might have great potential application in targeted drug delivery system or cell separation.

The fatigue crack growth rate in 18–8 austenitic stainless steel can be effectively reduced due to the strain-induced transformation at the fatigue crack tip. X-ray diffraction analyses of fracture surfaces indicate that the type of transformation products corresponds to different fracture mechanisms of materials. The transformation products are mainly α - Martensite for the fatigue striation mechanism, but e-Martensite for the dimple mechanism. Experimental evidence shows that an extreme plastic region exists at the fatigue crack tip.