Transition metal ion-doped titanium dioxide (TiO2) powders were prepared by mechanochemical milling. Photocatalytic properties of the prepared semiconductor were evaluated using photodegradation of methylene blue under UV and visible light. Dye bleaching was observed spectrophotometrically. Color removal was reached after 120 min. The effect of varying concentration of organic dye, amount of TiO2 photocatalyst, particle size, pH, and stirring rate was observed on the efficiency of reaction. The maximum photocatalytic decomposition of methylene blue solution was achieved with 25nm particle size TiO2, which was ascribed to the enlarged surface area. All obtained results were discussed.

Modal analysis, which is applied to verify the vibration characteristic of structures, is the basis of various dynamic analyses. In this paper, firstly, a cable-stayed space truss, consisting of stay cables, columns and space truss, is built in ANSYS. Secondly, modal analysis is performed to confirm the natural frequencies of the structure and 10 modes are extracted. Thirdly, a modal neutral file including all necessary information of flexible bodies is generated by ANSYS and then imported into ADAMS for further modal analysis. Finally, comparison of results between ANSYS and ADAMS are summarized and qualitative analysis is carried out aiming at the difference of natural frequencies between ANSYS and ADAMS. The simulation results indicate that the interface between the two tools has strong compatibility regardless of minor errors in it.

The design of fuzzy controller is the key of fuzzy control system, while the core of fuzzy controller design lies in fuzzy rules, whose performance determines the control effect of fuzzy system. General fuzzy rules are obtained from expert experience, in which much subjectivity exists. In this paper, a fuzzy controller is designed by taking an intelligent cantilever beam as the research object. And a method using the genetic algorithm to optimize fuzzy rules is proposed and the genetic coding as well as the fitness function is confirmed. Finally, the simulation model of intelligent cantilever beam is built by Matlab/Simulink, and the vibration control effects of fuzzy controller optimized by genetic algorithm are compared with those un-optimized. The simulation results indicate that the vibration amplitude of intelligent cantilever beam has a significant decrease and the vibration decay rate has a significant increase after the fuzzy rules optimized.

Titanium silicon carbide (Ti3SiC2) is a remarkable material for its combination of the best properties of metals and ceramics. The high purity Ti3SiC2 ceramic has been prepared by infiltration sintering (IS), and the effect of a small amount of Si on Ti3SiC2 ceramic formation was investigated. The results show that the purity of Ti3SiC2 ceramic could be increased significantly and the sintering time for Ti3SiC2 could be decreased remarkably when proper amount of Si was added in the starting mixture. The Ti3SiC2 sintered compact with a purity of 99.2wt% and a relative density of 97% was obtained by the infiltration sintering from a starting mixture composed of n(Ti):n(Si):n(TiC) = 1:0.3:2 at 1500 °C with holding time of 2/3h.

The mixture proportion of recycled concrete was discussed by orthogonal design method. The influence of water-cement ratio, recycled aggregate quantity on workability, cube compressive strength of recycled concrete was analyzed. The experimental results indicated that，Recycled concrete mix proportion design should consider the impact of the water absorption of recycled aggregate. Unit water amount of recycled concrete should be plain concrete unit water consumption and recycled aggregate additional amount of water. Sand ratio should increase in the corresponding ordinary aggregate concrete sand ratio on the basis of 1 to 3 percent. When the water-cement ratio is 0.36 and construction waste content of 40% slag content of 20%, 28d compressive strength of concrete is 48.1MPa, slightly higher than the reference concrete (48.0MPa).