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In this paper, ultralong ZnO nanowires were prepared on the surfaces of nickel foams and zinc foils by a hydrothermal method. The photocatalytic activities of ZnO nanowires grown on nickel foams have been tested by the degradation of Rhodamine B solution and using ZnO nanowires grown on zinc foils as the reference. The results indicate that the photocatalytic performance of ZnO nanowires grown on nickel foams is better than those grown on zinc foils. The results are mainly due to the fact that nickel foam is a three-dimensional scaffold structure, which provides large surface area for ZnO nanowire growth. More importantly, the photocatalytic circulation experiments indicate that ZnO nanowires grown on nickel foams are stable and reusable. In addition, the photocatalytic reaction rates can be enhanced by the use of multi-layer of nickel foams with ZnO nanowires grown on their surfaces.

Considering the fact that large surface areas and fast electron transport properties of photoanodes play an essential role in determining dye sensitized solar cell efficiency. A centrifugation-assisted method was designed to fabricate nanoparticle decorated hierarchical nanowire arrays. The hierarchical nanostructure arrays enable the fast charge transport properties of the photoanode. At the same time, the nanoparticles and the hierarchical nanostructures work together to guarantee the large surface areas of the photoanodes. During the fabrication process, TiO2 hierarchical nanowire arrays were firstly fabricated on fluorine doped tin oxide substrates via a hydrothermal method and then nanoparticles were deposited subsequently in the interval spaces among the neighboring nanostructures. Field-emission scanning electron microscopy and X-ray diffraction were used to characterize the morphology and structure of the obtained products, respectively. The results show that the nanoparticles do deposit in the interval spaces among the hierarchical nanowires forming a hybrid structure composed of anatase and rutile TiO2. The obtained nanoparticle decorated hierarchical nanowire arrays have been successfully applied in dye sensitized solar cells. A power conversion efficiency of 5.52% was achieved with the photoanode film thickness of about 20 µm.

This study investigated the effect of different specific surface area micronized zinc oxide (ZnO) on growth performance, zinc (Zn) tissue content, jejunal morphology, jejunal antioxidative status, and intestinal mucosa barrier-related gene expression in meat ducks. A total of 480 one-day-old Cherry Valley ducks were randomly divided into 4 dietary treatments, which each had 12 replicates; therefore, each replicate consisted of 10 ducks. Experimental diets included the basal diet supplemented with ZnSO4 (control group) and 3 different treatments of specific surface area micronized ZnO, in which the specific surface area was either 11.30 m2/g (S-mZnO), 20.90 m2/g (M-mZnO), or 34.02 m2/g (L-mZnO). The amount of Zn extra supplementation in the 4 diets was 120 mg/kg of diet. The experiment lasted for 35 D. The results showed that supplementation of M-mZnO significantly increased (P0.05) the BW (35 D), the BW gain (14 to 35 and 1 to 35 D), the jejunal crypt depth, and mRNA expression of zonula occludens-3, mucin 2, and secretory immunoglobulin A of ducks, while the feed-to-gain ratio (14 to 35 and 1 to 35 D) significantly decreased (P0.05) when compared to the control and the other 2 supplementation groups. Furthermore, compared with control group, the hepatic Zn content and the jejunal superoxide dismutase activity in the 3 micronized ZnO groups were significantly increased (P0.05), and the Zn content in the pancreas tended to increase (P = 0.051). In conclusion, this study demonstrates that M-mZnO as a dietary supplement can improve the growth performance of meat ducks by increasing the Zn tissue content and improving intestinal morphology, antioxidative status, and physical, chemical, and immunological barrier function.

In order to improve the performance of ZnO-based solar cells, ZnO/CdS core/shell heterostructures were synthesized via a facile chemical conversion route. Large area and quasi-aligned ZnO nanowire arrays were firstly fabricated on conductive glass substrates, and then the synthesis of ZnO/ZnS and ZnO/CdS heterostructures were realized by a chemical conversion method. The morphology and structure of the obtained products has been confirmed by field-emission scanning electron microscopy and X-ray diffraction measurements. The synthesized ZnO/CdS core/shell heterostructures were successfully applied in solar cells. The photovoltaic performance investigation demonstrates that the synthesized ZnO/CdS heterostructure-based solar cell shows a higher short-circuit current density compared with the N719 dye-sensitized ZnO nanowire array counterpart. The enhancement in current density may be due to the fact that the surface coverage of the light absorption layer in the ZnO/CdS core/shell heterostructure is very high. These results indicate that the synthesized ZnO/CdS heterostructures by the present method are very suitable for the application as photoelectrode in solar cells.

In recent years, with the development of the researches on aviation, space and energy fields, integral impeller, blisk, shrouded turbine blisk and hooded impeller have been used more and more broadly. The construction of these key parts is complex. Their weight is lighter than before. Their structural strength is enhanced. Their reliability and efficiency are greatly improved. And these parts are made of anti-high temperature and corrosion resistance materials. These characters make it difficult to machine them precisely. In this paper, five-axis EDM equipment is developed to solve this problem. Based on this equipment, the processing techniques of integral impeller, blisk, shrouded turbine blisk and hooded impeller are researched. And the electrodes are designed. The discharge conditions and machining trajectories are optimized. Finally, the eligible work pieces such as shrouded turbine blisk and hooded impeller have been made by using the research result.

The attraction force between the AFM tip and the surface of sputtered dielectric thin films (SiO2 and ZrO2) was measured with atomic force microscope (AFM) by applying DC-bias between the AFM tip and the n-Si substrate. Under 0 electric field, there exists van der Waals interaction between the AFM tip and the surface of dielectric films. When DC voltages are applied, the attraction force increases obviously for thin SiO2 (5.2 nm) and ZrO2 (6.8 nm) films due to the columbic interaction between them. A parallel-plate model has been developed to evaluate the ideal columbic tip-surface force for SiO2 and ZrO2 films. Contrary to the calculation result, the columbic force for ZrO2 film (6.8 nm) is lower than that for SiO2 film (5.2 nm), indicating the poor dielectric properties of the ZrO2 film. The poor dielectric properties of ZrO2 film should be due to the interfacial SiOx-containing layer formed between ZrO2 and Si, supporting the conclusion reached in the literature that the interfacial SiOx-containing layer can deleteriously influence the dielectric properties of high-k films.

In design of aqueduct structure, natural frequency calculation is the basis of earthquake response analysis. In this paper, the dynamic characteristic of Gegou U shape aqueduct is calculated by the finite element software ANSYS. And in this software, the interaction between water and aqueduct wall is simulated with added mass method. Natural vibration frequencies and principal modes of Gegou U shape aqueduct are analyzed and calculated in four different water level which include empty tank water level, semi tank water level, design water level and bank-full water level. The calculation results show that the water level has a great influence on the natural frequencies of the aqueduct and the frequencies decrease with the increase of water level. The research results can provide basis for its protection and seismic design of U shape aqueduct. Keywords-Gegou aqueduct; ANSYS; natural frequency; vibration mode; added mass

In this paper, the finite element method was used to analysis the modal characters of a reinforced concrete pedestrian bridge structures. The relationship between parameters and structural vibration frequency was found by parametric analysis. Structural dynamic conditions corresponding state occurred was mainly determined by main modes. In practice, simulated operation, bridges can be analyzed by the previous stage of the natural frequencies and the mode shapes in order to assess. Keywords-pedestrian bridge; modal analysis; dynamic characteristics; natural frequencies; mode shapes