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When zirconium alloy is corroded, an oxide film is formed on the surface, which hinders the ion transfer during the corrosion process. Therefore, the analysis of the oxide film is an important part of the research on the corrosion resistance of zirconium alloys. In this paper, two kinds of Zr-Sn-Nb alloys were corroded in 400 °C/10.3 MPa pure steam and 500 °C/10.3 MPa pure steam in autoclave to obtain samples with oxide thickness of 14 um and 18 um respectively. Then they were annealed at 800 °C at a pressure of 10^-4 Pa for 18 h. XRD and WDS studies were used to analyze the structure and oxygen content of the oxide film after annealing. The results indicate that the oxide films of alloys change from zirconium dioxide to zirconium after annealing. The oxygen diffuses into the substrate and its content decreases continuously with increasing diffusion distance. Combined with the SEM analysis of cross-section samples, it is found that the annealed samples are composed of several layers. An oxygen-saturated zirconium layer, a transitional layer with micro-cracks, an oxygen-dissolved α-Zr layer and a β-Zr layer are identified. Based on these results, the mechanism of the ion transfer in the oxide film during annealing is analyzed deeply. It is proposed that space charges in the oxide film have a major impact on deoxidation kinetics. This study provides a new research method for the corrosion mechanism of zirconium alloys.

Miniature pore pressure transducer (PPT) Druck PDCR81 series are used widely and have been proved to have a good performance in the centrifugal tests in the past few decades. However this product has been off production due to unknown reasons from 2010. Therefore, an alternative PPT is urgently needed in the centrifuge research field. A series of comparison between a new PPT and PDCR81 series had been carried out to check its precision and responding rate at 1g and centrifugal condition. The results show that the new PPT has a nearly equivalent performance to PDCR81 series. Also some suggestions are given to modify this new PPT.

Effect of iron ore tailings as fine aggregate on pore structure of mortars has been studied in this paper. The purpose is to investigate, as fine aggregate, comparing to natural sand, whether the iron ore tailings can improve the pore structures of mortars or not. Pore structure parameters were measured with the instrument of MIP and calculated with corollary software. The pore structure parameters from four kinds of mortars with different fine aggregates are compared with each other. This paper will provide more data about the use of this artificial aggregate, which may increase the feasibility of the use of this by-product in the mortar or cement concrete industry.

With the rapid development of reinforced earth technology, different reinforced materials are also gradually applied to Reinforced earth. In this paper, we focus on the need for the study of interface characteristics between different reinforced materials and clay, by making indoor drawing test with two kinds of reinforced materials commonly used in engineering and the same clay. The test results show that: the drawing strength between the two reinforced materials and clay both increase with the normal stress increasing, both of their strength envelopes are straight lines; In the drawing test between the warp knitted geogrid and clay, the cohesive strength is 6.65kPa, the friction angle is 21.03°; while the drawing test between the geonet and clay, the cohesive strength is 2.9kPa, the friction angle is 10.96°; The average tensile strength of warp knitted geogrid is 26.4% of genet's, while the drawing strength of warp knitted geogrid in the test is about 48.1% of genet's, so when chosing reinforced materials in some engineerings, it is an important factor that we must consider the particle size and gradation of the filled reinforced materials, selecting the most appropriate size effect.

In the present study, we investigated the protective effect of anthocyanin extract from Lonicera caerulea var. edulis (LCA) on UVC-induced lipid and protein peroxidation using lecithin and Bull Serum Albumin (BSA) in vitro model. We also investigated the protective effect of anthocyanin on UVC induced cell injury in Spleen lymphocytes of mouse via MTT and comet assays. Peroxidation of lecithin and BSA generated by exposure to UVC radiation was significantly decreased by addition with various concentrations of LCA. Moreover, LCA exhibited an inhibitory effect on DNA damage induced by UVC radiation when compared with the control group, the DNA damage decrease at the LCA concentration of 50-200ug/ml, in comet assay. These results indicate that LCA has certain protective effect to ultraviolet radiation damage.

The recent local wars appeared a lot of information characteristics. In future wars, one who master information dominance in battlefield will become more active. In a sense, one who controls the information in the battlefield will grasp the whole initiatives in the war. In the paper, we have researched the methods of grasping the information dominance.

Sludge from the textile dyeing industries was solidified and stabilized using cement, fly ash（PFA）and cinder as the solidifying agents, and the optimum conditions of sludge solidification/stabilization were analyzed. The mechanical property of solidified sludge block was evaluated by compressive strength test, at the same time， the chemical oxygen demand (COD） and heavy metal concentration of the leaching from the cured block were tested as well. With the dosage of cement, PFA and cinder, 0.15kg/kg, 0.02kg/kg and 0.08kg/kg respectively, and curing time was 6ds, the compressive strength of the solidified sludge block reached 330kPa.Results showed that addition of cement and cinder had good effects on the compressed strength of sludge block, cement, PFA and cinder enhanced the solidification and stabilization of organic and heavy metal in the sludge. Under the above conditions, COD of the leaching from the sludge solidification block was 488mg/L, and the heavy metal concentrations had reached the related national standards. After 6ds of curing time, water ratio of the solidified block was maintained at 40%~45%, which met the prescribed standards of landfill.

A kind of environment-friendly Cr-free insulating coating for grain-oriented electrical steel is exhibited in this paper. The tensile stress and the magnetic properties for both Cr-free and Cr-containing insulating coating were measured. The results showed that the more the coating on the metal, the bigger the tensile stress produced. The contribution of the Cr-free insulating coating to the reduction in P_1.7/50 varies from 0.092 to 0.192 W/kg, while the reduction in P_1.7/50 by the Cr-containing insulating coating is from 0.066 to 0.177 W/kg, with the weight of the coating varies from 4 to 6.5 g/m². In comparison with the traditional Cr-containing insulating coating, the Cr-free coating produces larger tensile stresses in the metal, thus leads to better magnetic properties, especially in the magnetic losses. Keywords: grain-oriented electrical steel, insulating coating, Chromium-free, magnetic property, tensile stress

Auxiliary power of Three-phase photovoltaic inverter is supplied by solar cells with wide input ranging from 140V to 1000V.The conventional single-switch flyback converter exists too high voltage stress in power switch to be applied in this inverter. This paper presents a dual-switch flyback converter in which the voltage stress of each switch is slightly higher than the input voltage when switches turn off, at the same time , the leakage inductance energy is recycled back into the inputside; otherwise, this topology needs no snubber circuit, so it is much more efficient than single switch flyback. The dual switch flyback converter with seven outputs is successfully applied in 10KW three phase PV inverter.

To investigate the influence of ethanol catalyzed oxidation on activity of Pd/C with different ratio of Pd and C. Pd/C catalyst samples with Pd loads of 20, 30, 40 and 50 wt% were obtained by chemical reduction reaction of PdCl₂ and NaBH₄. The samples morphology and structure were characterized by XRD and SEM. The electrocatalytic oxidation activities of ethanol were examined by cyclic voltammetry in alkaline media. The results show that a face centered cubic (FCC) Pd phase can be identified in the sample powders. The average particle size of the Pd/C powder is about 10 nm. The performance of ethanol oxidation on 40 % Pd/C electro-catalyst is better than that of the other Pd/C samples.