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Microstructure evolution and hardening effect of pure tungsten and W–1.5%ZrO2 alloy under carbon ion irradiation are investigated by using transmission electron microscopy and nano-indentation. Carbon ion irradiation is performed at 700 °C with irradiation damages ranging from 0.25 dpa to 2.0 dpa. The results show that the irradiation defect clusters are mainly in the form of dislocation loop. The size and density of dislocation loops increase with irradiation damages intensifying. The W–1.5%ZrO2 alloy has a smaller dislocation loop size than that of pure tungsten. It is proposed that the phase boundaries have the ability to absorb and annihilate defects and the addition of ZrO2 phase improves the sink strength for irradiation defects. It is confirmed that the W–1.5%ZrO2 alloy shows a smaller change in hardness than the pure tungsten after being irradiated. From the above results, we conclude that the addition of ZrO2 into tungsten can significantly reduce the accumulation of irradiated defects and improve the irradiation resistance behaviors of the tungsten materials.

Scanning electron microscope (SEM), X-ray diffraction (XRD), VSP electrochemical workstation and friction and wear tester equipment are applied for comparing the effects on organizations and properties of micro-arc oxidation fabricated on a piece of aluminum alloy sample with additives of La (NO3)3 or Ce (SO4)2. The results revealed that both coatings with these two different additives are consisted of α-Al2O3 and γ-Al2O3, but the peaks of main phases are evident with La (NO3)3. Compared the two different coatings, it could be found that less micro-cracks can be observed from the coating with La (NO3)3 additive. Beside this, aperture in this coating is also smaller and corrosion resistance and wear resistance are much better.

The lattice parameters, elastic constants, cohesive energy, structural energy differences, as well as the properties of point defects and planar defects of hexagonal close‐packed yttrium (hcp‐Y) have been studied with ab initio density functional theory for constructing an extensive database. Based on an analytical bond-order potential scheme, empirical many‐body interatomic potential for hcp‐Y has been developed. The model is fitted to some properties of Y, e.g., the lattice parameters, elastic constants, bulk modulus, cohesive energy, vacancy formation energy, and the structural energy differences. The present potential has ability to reproduce defect properties including the self‐interstitial atoms formation energies, vacancy formation energy, divacancy binding energy, as well as the bulk properties and the thermal dynamic properties.

Ceramic coatings were fabricated on casting aluminum-copper alloy through micro-arc oxidation by mixing Ce(SO4)2 into the silicate electrolyte. The effects of Ce(SO4)2 additive on the ceramic coatings were analyzed by means of SEM, EDX, XRD, hardness and corrosion tests. The results show that Ce(SO4)2 effectively promoted the reaction of the MAO coating surface, increased the thickness and hardness of the coating and enhanced the corrosion-resisting property. The optimal addition amount of Ce(SO4)2 in the electrolyte is 0.2g/L.

Cu(OH)2/N-TiO2compound heterojunction photcocatalyst was prepared via a facile precipitation method. The as-synthesized samples were characterized by means of X-ray diffraction (XRD), field-emission transmission electron microscope (FE-SEM), ultraviolet-visible light (UV-vis) absorbance spectra technologies. The results suggest the as-obtained samples are spherical structure with the diameter of approximately 10-20 nm, the absorbance intensity in the visible light range increased with the amount of deposited increased. Photocatalytic activities of samples were investigated under visible light and methyl orange (MO) acted as simulation pollutants. The catalytic ablity of the synthesized photocatalysts under visible light irradiation showed higher than that of N-P25(TiO2). The remarkable photocatalytic activities are due to the high-quality of composites structure and the driving force for electron transfer in nanoparticle.

In this paper, a facilesolution method was employed to synthesize the graphene-NiO composite. SEM and XRD results indicated the graphene sheets were covered by the NiO nanoplates. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to measure the electrochemical properties of the composite. The specific capacitance reached 1292F/g at a scan rate of 5mV/s. The results show that this composite is a promising material for supercapacitor electrode.

Micro-arc oxidation (MAO) process was carried out in a dual electrolyte system of NaAlO2 and Na3PO4 to develop compact, smooth and corrosion-resistant coatings on ZK60 Mg alloy by single factor experiments. The microstructural characteristics of coatings were investigated by X-ray diffractometry (XRD) and scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS). Test of mass loss was conducted at a 3.5% NaCl solution to assess the resistance to corrosion. The effect of every element in the dual electrolyte system on voltage-time responses during MAO process and the coating characteristic were also analyzed and discussed systematically via single factor experiments. The results reveal that the main components of NaAlO2 and Na3PO4 as well as additives of NaOH, NaB4O7 and C6H5Na3O7 demonstrate different effects on MAO process and coating characteristics. By means of single factor experiments, an optimized dual electrolyte system was developed, containing 17.5 g/L NaAlO2, 5.0 g/LNa3PO4, 5.0 g/L NaOH, 3.0 g/L NaB4O7 and 4.2g/L C6H5Na3O7.

Pratylenchus ekrami from maize (Zea mays) roots in Shenyang and luffa (Luffa cylindrica) roots in Dalian, China, are described in this paper. Nematodes from the two areas were identified consistently, and were characterized by a heavy cephalic sclerotization, extending posteriorly up to two body annuli, stylet 11-13 μm long, elongating conoid tail, and becoming thinner from vulva. Males were not found. Pratylenchus ekrami is close to Pratylenchus vulnus, but the most critical characteristics between the two species were the number of lip annuli, stylet size, and shape of stylet knobs. This species is the first reported in China.

Raman spectroscopy was used for experimental research on D2 signal to noise ratio (SNR) under different conditions. The 32 mW Ar+ laser was injected into the Raman quartz glass cells to study the effect of grating, laser power, exposure time and the gas pressure on D2 Raman spectra SNR. D2 Raman spectral signal to noise ratio is proportional to the laser power, exposure time and gas pressure. The standard curve of the pressure and SNR for this experimental apparatus was obtained. Three sets of random samples were used to verify the formula SNR(J 2 --2) = 10.6 x 10(-4) p+1.271 34. When the deuterium pressure is 21 280 Pa, the relative error is 4.8%. When the pressure increases to 67 235 Pa, the relative error is down to 1.46%.

Carbon nanotube supported CuO is synthesized and applied as highly active and reusable heterogeneous catalyst for the construction of highly substituted furan derivatives (III).

As heterogeneous catalysts and nanoparticle support materials, CNTs have attracted great interest in organic chemistry. This paper reports facile CuO/CNTs-catalyzed cyclization to form furan derivatives from electron-deficient alkynes and α-hydroxy ketones. It represents a facile synthetic route, and the eco-friendly catalyst can be easily separated by filtration and reused.