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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.

The filtration characteristics of untreated sewage sludge, thermal alkaline pretreated and anaerobic fermented sewage sludge were investigated in the process of fatty acids production. The filtration resistance, viscosity, particle size, extracellular polymeric substances (EPS) and soluble microbial products (SMP) were determined to identify the filtration characteristics of the sewage sludge. The results indicated that thermal alkaline pretreatment significantly increased the filtration resistance and viscosity of the sewage sludge, while anaerobic fermentation decreased the filtration resistance. The particle size of the sewage sludge decreased after pretreatment and fermentation. Moreover, the EPS concentration in the sludge sharply decreased after thermal alkaline pretreatment and then increased after the following fermentation. The mechanism of the increase of sludge filtration resistance after pretreatment could be attributed to the release of EPS from the microbial cells of the sludge. The degradation and conversion of SMP into volatile fatty acids could explain the decrease in the filtration resistance after fermentation.

National High Technology Research and Development Program of China [2009AA03Z327]; Scientific and Technological Innovation Flat of Fujian Province [2009J1009]

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.

The temperature-dependent self-diffusion coefficient D ( T ) in liquid metals between the melting temperature T m and boiling point T b is modeled in terms of the relationship among D , liquid viscosity η , and liquid–vapor surface tension γ lv . The model predictions for D ( T ) correspond to available experimental and molecular dynamics (MD) simulations results for liquid alkali metals Li, Na, Rb and Cs, semi-metal Al, transition and noble metals Ni, Cu, Ag and Au.

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.

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.

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.

TiO 2 was prepared by the oxidation of TiCl 4 at relatively low deposition temperatures using spray pyrolysis. For a fixed carrier gas (N 2 ) flow rate, the substrate temperature is the critical parameter determining the film properties. Films made near 595 K contain only the anatase phase, adhere well to the glass substrate, and have a relative optical transmission of about 75% (between 450 and 850 nm), the value one calculates for the non-absorbing anatase phase in this region. These films have an absorption edge characteristic of a direct gap semiconductor with allowed transitions and optical gaps of 3.5–3.7 eV, depending on the porosity. At higher substrate temperatures (above 635 K), the resulting films have a cloudy appearance and they contain both the rutile and the anatase modifications, confirmed by X-ray diffraction. Lower temperature substrates reduce the deposition rate and yield more porous films. For the pure anatase films, the dark conductivities are about one order of magnitude larger, and the photoconductivity is about one order of magnitude smaller when measured with the sample in air, than those observed when the sample is in a vacuum. When the samples are in a vacuum, the conductivities of the clear films increase by about two orders of magnitude (from about 10 −10 to about 10 −8 S cm −1 ) when illuminated with light from an electrically programmable read-only memory eraser (mercury light), which gives an intensity of about 30 μW cm −2 at the sample. The photoresponse has two parts; the fast portion rises in less than 1 s to 99% of its final value, followed by a small slow rise portion. The slow response, which is more pronounced in the decay process, is interpreted as being due to the presence of surface trapping states.