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A thick Fe-based amorphous and nanocrystalline composite coating was prepared by in-situ tungsten inert gas (TIG) cladding method. The results show that the cladding coating mainly consists of amorphous phase and nanocrystalline grains. The microstructure study shows that the Fe-based composite coatings have unique microstructure including nano-sized grains surrounded by nano-scale amorphous shell layer (encapsulated structure) and the homogeneously distributed dendrites/cellular crystals. The unique microstructure gives rise to the superior micro-hardness and wear resistance of the coating. The Fe-based coatings have great potential as promising wear-resistance structural materials used in electric power and cement industry.

At present, gas disaster is one of the main problems for Chinese coal industry. The prevention and control of gas accident is an important part of coal mine enterprise production safety. This paper uses wireless sensor network to collect the coal mine gas concentration parameter, transmits and stores the data to the server of gas monitoring system by information fusion of sink, and synchronously displays the data to the client in the state of three-dimensional space. When the gas concentration of monitored coal mine roadway is greater than the limit, the sound and light alarm will be trigged and the alarm area will be displayed. In the meantime, the information of contingency plan will be provided. The system gives a strong technical support for the early warning and controlling of gas disaster and provides a reference for the prevention of gas accidents in coal enterprises.

The homogeneous rare-earth catalytic system was used to initiate the polymerization of isoprene, and a novel IR was synthesized with high molecular weight and narrow molecular weight distribution. According to the self-developed rare-earth IR properties, a study on IR and IR/NR blend was made. The effect of JiHua rare-earth IR on the vulcanization characteristics and dynamic properties in IR/NR blend was investigated and compared with IR (SKI-3) synthesized with titanium catalyst system and rare-earth isoprene rubber (SKI-5) made in Russia. The results showed that JiHua rare-earth IR to be developed independently was a novel synthetic rubber with excellent comprehensive performance, and it can be used independently and partly substitute natural rubber to make tire. In the IR/NR blend, Not only vulcanization characteristics and the safety in operation for NR was greatly improved, But also dynamic properties of vulcanizates such as dynamic cutting resistance, abrasion resistance, wet-skid resistance and aging resistance were improved to different degrees. These properties reach or surpass the level of the foreign similar products like Russia SKI-3 and Russia SKI-5.

With the increasingly competitive pressure, spunbond nonwoven products marketed is becoming more cost sensitive. Inorganic additives, which is mainly composed of calcium carbonate , has been mixed into the standard organic spinning solution for either reducing the raw material cost or enhancing some of the physical properties. Therefore, its necessary to find a test method to evaluating the quality of these products. This paper developed a test method for determining the amount of inorganic additives and calcium carbonate in nonwovens by thermogravimetry analysis, and proved its effectiveness.

To study the velocity and pressure distribution of the oil film in a heavy hydrostatic thrust bearing, a mathematical model of the velocity is proposed and the finite volume method (FVM) has been used to simulate the flow field under different working conditions. Some pressure experiments were carried out and the results verified the correctness of the simulation. It is concluded that the pressure distribution varies small under different rotation speed when the surface load on the workbench is constant. But the velocity of the oil film is influenced greatly by the rotation speed. When the rotation speed of the workbench is as quick as enough, the velocity of the oil film on one radial side of the pad will be zero, that is to say the lubrication oil will be drained from the other three sides of the recess.

Simvastatin, as one of the HMG-CoA reductase inhibitors for lowering lipids, has been demonstrated its potential benefit in bone formation, which was, however, conflicting and inconclusive in vivo studies. Thus, we performed this study to assess the in vivo effects of simvastatin on bone formation. Six-week old rats were administered with simvastatin (20 mg/kg/d) or vehicle for 6 or 9 weeks. All animals were sacrificed one day after the final administration. The left femora were removed for the measurement of bone histomorphometry and bone mineral density (BMD).Compared to the control groups, on both 6th week and 9th week, bone mineral density and bone histomorphometry detected no significant differences in bone mass and microarchitecture in simvastatin treatment group, as well as bone formatin/resorption parameters. These results indicate that simvastatin had no positive effect or impact on bone in rats administered with high dose simvastatin (20 mg/kg/d) for 6 or 9 weeks.

Precision machining of thin-walled complex components has been a serious challenge, and the machining errors are mainly due to cutting force which can induce tool-workpiece deformation and chatter vibration phenomenon. Based on the principle of stiffness optimization and material removal sequence optimization, rigidity of thin-walled component is greatly improved with non-uniform allowance distribution and spiral milling process techniques.

In allusion to the management characteristics of the cement laboratory samples, this paper conducts introduction and comparative analysis on such four kinds of identification as inspection organization, traditional cement sample identification of corporate laboratory, paper-electronic tags and wireless monitoring devices. It shows that wireless monitoring devices are superior to the traditional sample identification and paper-electronic tags, and can achieve intelligent management of cement samples ensuring objective and fair inspection data.

Nano-sized nitrogen-doped Ti-W mixed oxides (N-TiO2-x%WO3) were prepared by soft chemical method, and their intrinsic characteristics were investigated using XRD, TEM, N2 adsorption and desorption isotherms, UV-Vis diffuse reflectance spectra and XPS. Experiments on photodegradation of Methylene Blue (MB) under visible light irradiation were carried out to evaluate the photocatalytic abilities of N-TiO2-x%WO3. Chemical Oxygen Demand (COD) analysis was also performed to evaluate the mineralization abilities of N-TiO2-x%WO3. It is shown that the N-TiO2-x%WO3 exhibited higher COD removing rates compared with Degussa P25. The color bleaching rates of N-TiO2-x%WO3 were equal to that of Degussa P25. The enhanced photocatalytic activities were probably related to the strong absorption abilities of the N-TiO2-x%WO3.