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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.

Mg-based materials are very promising candidates for hydrogen storage. In this paper, the graphene supported Ni was introduced to the Mg90Al10 system by hydrogenation synthesis (HS) and mechanical milling (MM). The 80 wt%Ni@Gn catalyst was synthesized by a facile chemical reduction method. The microstructures of the catalyst and composite show that Ni nanoparticles are well supported on the surface of graphene and they are dispersed uniformly on the surface of MgH2 particles. After heating to 450 °C and holding at 340 °C for 2 h subsequently under 2.0 MPa hydrogen pressure, all the samples are almost completely hydrogenated. According to the temperature programmed desorption test, the Mg90Al10-8(80 wt%Ni@Gn) composite could desorb 5.85 wt% H2 which comes up to 96% of the theoretical hydrogen storage capacity. Moreover, it shows the optimal hydriding/dehydriding performance, absorbing 5.11 wt% hydrogen within 400 s at 523 K, and desorbing 5.81 wt% hydrogen within 1800 s at 573 K.

A novel embedded Mg-based hydrogen storage nanocomposite was prepared by mechanical milling of hydriding combustion synthesized (HCS) Mg-based hydride and hydrogen permissive/oxygen prohibitive polymer. The Mg-based hydride was mechanically milled with tetrahydrofuran solution of polymethyl methacrylate (PMMA) under argon atmosphere. It is determined by X-ray diffraction (XRD) analysis that the average grain size of all the milled nanocomposites become smaller and the nanocomposites exhibit a good air-stable property. The microstructures of the nanocomposites obtained by Field emission scanning electron microscopy (FESEM) and High-resolution transmission electron microscopy (HRTEM) analyses show that Mg95Ni5 particles embedded by PMMA have a diameter of smaller than 100 nm, approximately. The nanocomposites show the optimal hydriding/dehydriding properties, requiring 60 min to absorb 3.37 wt.% hydrogen at low temperature of 473 K, and desorbing as high as 1.02 wt.% hydrogen within 120 min at the same temperature. The onset dehydriding temperature of the composites is about 373 K, which is 150 K lower than that of HCS products Mg95Ni5.

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.

Water-soluble CdSe nanoparticles have been synthesized from aqueous solution of selenosulfate by using mercaptocarboxylic acid as stabilizer. A comprehensive investigation is presented on the growth mechanism of CdSe nanoparticles and the factors determining the size. The growth mechanism of CdSe nanoparticles composed two kinds of growth mode, aggregation and Ostwald ripening. The growth rate and product properties can be controlled by changing the reaction conditions. The best conditions, for synthesis of CdSe nanoparticles in the current system, are the pH value in the range of 9-10 and a large excess of the cadmium precursor. The structure of CdSe nanoparticles has been studied by using XRD, TEM, and HRTEM.

Ni nanocontacts have been grown by electrodeposition using a self-terminating technique in a single electrolyte bath based on nickel sulfate, nickel chloride and boric acid. Resistance measurements performed on different samples presented two kinds of obviously different magnetoresistance effects. The analysis of the data sets showed that magnetostriction might play a key role in magnetoresistance of the electrodeposited Ni nanocontacts.

One of the most important findings in the recent study of deformation and fracture in ordered intermetallics is that many intermetallic alloys with high crystal symmetries (such as L1{sub 2} and B2) are intrinsically quite ductile at ambient temperatures, and that their commonly observed low ductility and brittle fracture are caused mainly by extrinsic factors. Environmental embrittlement has been identified as a major extrinsic factor that embrittles many intermetallic alloys. In this case, the alloys showed brittle fracture and low ductilities when tested in moist air, but they exhibited distinctly high ductilities when tested in high-vacuum or dry-oxygen environments. In order to have a mechanistic understanding of moisture-induced hydrogen embrittlement, it is essential to have a direct measurement of trapped hydrogen atoms with position resolution. In this study, the authors try to develop a laser desorption mass spectrometric method to measure hydrogen atoms in a position-sensitive way. They also compare the amount of trapped hydrogen, with and without exposure to water, for FeAl containing 35.8 at. % Al.