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A method for the determination of seven hazardous elements in Non-stick Pan Materials in five food simulants by inductively coupled plasma mass spectrometry (ICP-MS) was established. Using this method, the experiments were carried out on the samples of imitated migratory elements (Cr、Mn、Ni、Cu、As、Pb、Cd) in food simulants of water, 4%(W/V) acetic acid solution, 10%(V/V) ethanol solution, 2g/L sodium chloride solution and olive oil. The sample preparation method of five food simulants was confirmed through experiment. Experiments by resolution, stability, sensitivity and other parameters were adjusted tuning instrument to determine the instrument to achieve the best working condition. The linear range of this methods was 0.1~50ng/ml. For all elements, the correlation coefficient of the calibration curves was above 0.9990 and the detection limits were within the range of 0.008~0.12ng/ml. Most of the recoveries at 1ng/ml concentration level was from 85.34%~112.3%, while the RSD was from 0.37%~4.1%.

In this study, the wear behavior of AM60 alloys adding different amounts of yttrium (0, 0.5, 1, 1.5, and 2 wt%) during dry sliding has been investigated. The microstructure observation and EDS analysis demonstrated that adding yttrium in AM60 alloy formed a new phase Al2Y and minimized the precipitation of Mg17Al12 phase. The wear rate and friction coefficient of AM60 alloys adding yttrium were lower than that AM60 alloy under the same condition. The worn surface was covered with long continuous grooves parallel to the sliding direction. The wear resistance of AM60 alloy was improved when yttrium was added due to the formation of uniformly is tribute finer and harder Al2Y precipitates. The harder Al2Y precipitates increased the hardness and wear resistance of the AM60 alloy and reached the maximum at 1 wt% Y.

In this paper, a circuit for the simulation of partial discharge (PD) ns pulse is introduced. An avalanche transistor, the main pulse generator in this circuit, is used to simulate the fast process of PD. PD pulse generation principle, pulse generating circuit and its drive circuit, the characteristics of ns PD pulse are described in detail in this paper. Meanwhile, the practicability of the circuit is proved by its application in PD phase calibration.

Nanotechnology is being used in UHPC for achieving more dense structural packing and better physical and mechanical properties. In this paper, nanosilica particles (0-1wt %) by cement were incorporated in cement pastes and mortars with water-binder ratio of 0.2, and their effect on fresh properties was addressed. The fresh properties of mixtures were investigated by spread, rheology and cohesiveness. In addition, effect of nanosilica on cement hydration was also investigated. The results show that significant increase of yield stress, viscosity and cohesiveness is observed with nanosilica above 0.005 wt% by cement, but nanosilica with content below 0.005% presents an improvement of workability especially with content of 0.002%. Moreover, the addition of nanosilica in cement pastes obviously accelerates the early cement hydration rate, but does not increase the cumulative heat evolution.

The thermodynamic parameter and microstructure of three contents as-cast magnesium alloys were researched by phase picture, X-ray diffraction and thermodynamic analysis, whereafter prepared semisolid billets by strain induced melt activation (SIMA). The microstructure observation and rheology parameter analysis demonstrated that add zinc content consumedly reduced formation temperature of semisolid microstructure, decreased isothermal holding time, and accelerated microstructure evolution. With increasing zinc content, the semisolid morphology better and better that is propitious to semisolid process. The analysis verified that on the one hand, with increasing aluminum and zinc content the melting point of compound and the nucleation temperature of liquid phase decreased, and the nucleation quantity of liquid phase increased; on the other hand, with increasing alloy content the as-cast microstructure much finer, which to caused much more fine and spherical semisolid microstructure.

The effects of ground slag with different specific surface area on the rheology of mortar at water-binder ratio of 0.25, 0.28 and 0.30 were investigated, and the combined effects of packing density and solid surface area on the rheology of mortar were evaluated in terms of the water film thickness. The results show that with the increasing of specific surface area of slag (220 m2/kg-784 m2/kg), plastic viscosity and yield stress decrease. The correlations of yield stress and plastic viscosity to the water film thickness are basically linear with high correlation R2 values. The action of the ground slag on the rheology of mortar can be characterized by water film thickness, and with the increasing of water film thickness the rheological parameters decrease.

The litter accumulation and decomposing biomass characteristics under meadow, typical steppe and desert steppe were comparatively studied. Results showed that accumulation and decomposition of litter was the biggest under meadow than typical steppe and desert steppe. Variance analysis indicated that accumulation mass and decomposition rate among the three steppe types were significantly different. Therefore, litters accumulation of different steppe types was greatly affected by precipitation and temperature.

Jankowskis bunting Emberiza janknowshkii Taczanovski is a glacial relict species. Habitat selection of jankowskis bunting Emberiza janknowshkii Taczanovski was investigated in Keerqin grassland of Inner Mongolia. The results showed that E. janknowshkii had obvious choice of habitat preference. Perch, the coverage of earth surface and height of plant had a significant impact on habitat selection of E. janknowshkii. Therefore, we should strengthen the protection for apricot, reduce human activities, such as cut grass, and protect height and coverage vegetation. And E. janknowshkii should be enclosure protected.

Defects might be formed within braided composites because of the special production process and would have negative effects on the mechanics performance of 3D braided composites. It is important to test and analyses defects to take preventive measures for preventing their formation. In this paper, defects of 3D braided composites were analyzed and methods of nondestructive testing were introduced. Ultrasonic nondestructive testing is one of the earliest methods of nondestructive testing used to evaluate composites. Ultrasonic nondestructive tests of 3D 5-directional braided composites were carried in this paper and the characteristics values were extracted by wavelet analysis method and defect qualitative analysis was implemented.

Recycled general-purpose plastic, polypropylene gained general acceptance because of its excellent properties. At the moment, most of experimental tests of short-natural fibers reinforced polymer composites have been concentrated on macro level, lead to un-matured of fine, micro mechanics research work. In this paper, flexural property of short flax fiber-reinforced polypropylene composites was numerical estimated using a FEM model. It has been observed that initial modulus of the composites increases with the rise in fiber volume fraction, while short fiber orientation distribution has little effect on composites; the stress-strain curves almost have no change.

Fabric keyboard is a field of smart textile. It can overcome many disadvantages of conventional keyboard. In order to study the fabric keyboard switch, trapezia structures of two kinds of orifice dimension are designed for example 8 wefts and 16 wefts. Different roots of conductive wires are woven into the down layer of the orifice part for each kind of orifice dimension. 4 and 8 roots of wires are woven for 8 wefts. 4, 8 and 16 roots of wires are woven for 16wefts. Then the immediate regain, connection pressure, connection ratio and contact resistance are tested and analyzed for every kind of fabric keyboard switch. It is concluded that 8 wefts orifice dimension and 8 roots of wires woven into the down layer of the orifice part is a better project. These findings may assist in recommendations regarding the further development of flexible fabric keyboard.

Based on the principle and fabricating process of Quasi-Isotropic braided composites, the regular pattern of movement of each yarn is analyzed and the inner unit cell model is established in this paper. The real Quasi-Isotropic braiding structure is built using 3D paint software named UG NX4.0. Compressive mechanical properties of 3D Quasi-Isotropic braided composites are also discussed. It is found that the load–deflection curve of the Quasi-isotropic braided composites displays a relatively linear behavior, behaving mostly as the characteristics of shear.

The paper researched the isothermal time and temperature affects the solid particles evolution of semisolid AZ91D alloy, and the alloy be produced by the method of strain induced melt activation (SIMA) ,and the method of compression ratio is 40%. The research demonstrated that the solid fraction decreased and solid particle size increased when increasing temperature and time. The isothermal coarsening of solid particles obeys Ostwald ripening which depending on the curvature of the interface, thus creating concentration gradients and the diffusion transport of material. As a result, the large particles coarsening and little particles minish even dissolved and creating change of distribution frequency of solid particle size. The fitting curves reveal that the experimental data are well fitted to the coarsening equation. The quantitative analysis of solid fraction and solid particle size demonstrated that the appropriate isothermal holding temperature is 550°C -590°C and corresponding isothermal holding time is (45-60min)-(6-20min) in 40% compression ratio.

The expanded graphite (EG) was prepared after microwave irradiation treatment of the expandable graphite in a domestic microwave oven at 1000 W for 60 s. The adsorption of methyl orange (MO) from aqueous solution onto EG was investigated at initial concentrations and contact time, different pH values, adsorbent dosage, temperatures for the removal of dye. The results confirmed that the adsorption isotherm data fitted to Langmuir isotherm with monolayer adsorption capacity of 13.37 mg/g. The results suggested that the EG would be an excellent adsorbent for the removal of MO by adsorption process.

After heated to high temperature, the strength test of concrete cube specimens made by siliceous and calcareous coarse aggregates was carried out. We analyzed the influence of cooling methods and standing time on concrete compressive strength respectively. The test results show that the compressive strength is generally decreased with increase in temperature. The relative residual strength of calcareous aggregate concrete is higher than siliceous aggregate concrete at higher temperature, so siliceous aggregate concrete has more significant fire resistance than calcareous aggregate concrete. Between 200°C and 550°C, the cooling methods have a great influence on concrete strength. The minimum of concrete strength appears at the 28th day after elevated temperature for both calcareous aggregate concrete and siliceous aggregate concrete in air cooling condition, whereas the minimum appears at the first week in water cooling condition. In addition, concrete strength values become steady with the lapse of time after the fire.

Monitoring coal goaf mainly is arrangement of the wireless sensor network node in goaf to monitor the change of gas concentration and environmental temperature. This paper presents a clustering routing algorithm based on event-driven. In conventional circumstances, we adopt an improved LEACH algorithm. In the case of an event occurs, the nodes within the event region form a sub-cluster automatically, electing a cluster head node in cluster center. Cluster head after fusion data, in the direction of the shortest distance with the sink node forms a series of dynamic clustering and transmits the data to the sink node. Through MATLAB simulation studies show that the improved LEACH prolongs network life cycle efficaciously, clustering routing algorithm based on event-driven will transmits the data to the sink node reliably and in real time.

We have surveyed the planting cost data and the yield data of wheat farmers in Shandong province in 2012. To analyze the effect of wheat planting cost for production, these data were divided into two groups according to their needs: with labor cost and none labor cost. Respectively using MATLAB software to the simulation calculation of the two groups of data, the conclusion is as follows. Regardless of labor investment, seeds investment costs and the pesticides investment costs have great effect to the wheat yield in Shandong Province.

The evaluating rules for semi-solid microstructure were brought up, and the analysis software was developed on MATLAB 7.0 platform in this study. Furthermore, this system can be used not only in the Thixomolding AZ91D magnesium alloy microstructure analysis, but also in the other semi-solid processing microstructure.