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In this paper, the Mg-Al hydrotalcite-like compound (Mg-Al-HTLC) was synthesized by hydrothermal method at 373K. Structure and morphology of Mg-Al-HTLC was obtained with X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transform infra-red spectroscopy(FTIR). A series of polar and non-polar molecules were used for probes, surface properties of Mg-Al-HTLC was studied by inverse gas chromatography (IGC) at 353K, 363K, 373K, 383K respectively. The retention volume was utilized for evaluating the free energy of adsorption (-ΔGSP), the dispersive component of the surface energy(γsD), as well as the enthalpy and entropic component(ΔHSP, -ΔSSP). XRD results reveal that the Mg-Al-HTLC has high crystallinity and perfect layered structure. The results of IGC show that Mg-Al-HTLC would adsorb straight-chain alkanes spontaneously, and the values of γsDwere similar at all temperature. It reveals Mg-Al-HTLC is a material with particular characteristics of both acid and base. This study illustrates that, as a method to evaluate the surface properties of material , IGC method is dependable and significant.

The selection of the flow stress model of materials has a great influence on the plastic forming simulation of metal. For closed extrusion fine blanking, selecting the accurate and appropriate material flow stress model can make the finite element simulation closer to the real situation, and the simulation data is more reliable. In order to solve the accuracy problem of finite element simulation closed-extruding fine blanking, 5 types of flow stress fitting curve equations were obtained based on the data of sheet metal tensile test. With the secondary development of finite element software Deform-2D, the circular piece of closed-extruding fine blanking forming process was simulated, whose diameter is 14 mm and thickness is 30 mm. The simulation results of different rheological models were compared after physical experiment being carried out.The results show that Ludwik extrapolation rheological model is suitable for finite element simulation of closed-extruding fine blanking technology, which effectively improves closed-extruding fine blanking simulation accuracy. Lay the foundation for the application of closed-extrusion fine blanking in industry.

In the paper, the relationship between the grain size and fatigue life are studied. To specify the initial and short crack propagation life of low carbon steel material, three methods are used in the simulation. At first, the K. Tanaka’s model is introduced to calculate the fatigue life of a grain. Then, the Voronoi Diagram is used to generate the microstructure of grains. At last, a criteria to specify the short crack is proposed. Based on these methods, the numerical simulation is conducted. With the help of the process, the grain sizes are generated randomly in order to specify how grain sizes effect fatigue life. The computational results are in good agreement with the experimental data. The results show that the randomness of fatigue life is closely related to the randomness of grain sizes.

Silicon nitride ceramic balls are successfully applied in advanced bearings. In order to improve the performance and precision for ball bearings, the research about the material properties of Si3N4 ball is shown in this paper. For the Si3N4 ball, the material properties can be described by the following factors: density, hardness, apparent porosity, crushing load and fracture toughness. In this paper, Si3N4 balls from three different manufacturers are tested to reveal the inherent correlations of the material properties, and the correlation coefficients are calculated. The results indicate that with the increasing of ball diameter, its crushing load increases correspondingly. The higher hardness contributes to the lower crushing load of the Si3N4 ball. Apparent porosity has a greater influence on the crushing load than hardness and the density. Hardness has the closest relevance with fracture toughness among the material characteristics, with the increasing of the hardness, the fracture toughness of Si3N4 ball becomes lower.

In this work, crystal structure, magnetic properties and magnetocaloric effect of Nd0.7Gd0.3Mn2Si2 alloy were studied by X-ray diffraction (XRD), Physical Property Measurement System (PPMS) and Differential Scanning Calorimetry (DSC). Nd0.7Gd0.3Mn2Si2 crystallizes in ThCr2Si2-typed structure with space group I4/mmm, in which the Nd, Gd, Mn and Si atoms occupy 2a (0, 0, 0), 2a (0, 0, 0), 4d (0, 1/2, 1/4) and 4e (0, 0, 0.38261) position, respectively. The Curie temperature (Tc) of Nd0.7Gd0.3Mn2Si2 alloy is 42 K, while the spin reorientation temperature (TSR) is 26 K and the Nel temperature (TN) is 410 K. The Tc and TN were determined using PPMS and DSC, respectively. The maximum value of the magnetic entropy change (-Smax) in the field change of 0-5 T is 11.862 J/kg K, while the value of relative cooling power (RCP) in Nd0.7Gd0.3Mn2Si2 alloy is 69.666 J/kg under the field change of 5 T.

The Fe-RE (RE=Gd, Tb, Dy, Lu) binary systems with the experimental data of phase equilibria and thermodynamic properties in the published literature were reviewed firstly. Based on available phase equilibria data and thermodynamic data, the Fe-RE (RE=Gd, Tb, Dy, Lu) binary systems were assessed thermodynamically using the CALPHAD method. As a result, further experimental investigations and thermodynamic calculations would be both required in order to develop thermodynamic database of the RE-Fe-B ternary systems, which is very useful to study the relations between alloy compositions, microstructure and magnetic properties of novel Nd-Fe-B-based permanent magnets.

Co3O4/Nitrogen-doped graphene (Co3O4/NG) composites were synthesized by a simple hydrothermal method. The Co3O4/NG composites show a better electrochemical performance than the Co3O4/graphene (Co3O4/G) composite. The specific capacitance of Co3O4/NG electrode is 428 F/g (290 F/g for Co3O4/G electrode) at a current density of 1 A/g. As the current density was increased from 1 to 8 A/g, the capacitance of Co3O4/NG still retained 57%, significantly larger than that of Co3O4/G (40%). Moreover, over 94% of the original capacitance was maintained after 500 cycles (72% for Co3O4/G electrode), indicating a good cycle stability of Co3O4/NG electrode materials.

The corrosion inhibition effect of composite inhibitors of sodium silicate on carbon steel was studied in 200 mg/L chlorine dioxide solution by static weight-loss method at room temperature (25 °C) .Analyzed the possible corrosion mechanism and the optimal conditions. The results show that sodium silicate and HEDP had apparent synergistic effect in chlorine dioxide solution. When the mass concentration of sodium silicate was 200 mg/L and HEDP was 100 mg/L can make the corrosion inhibiting rate on carbon steel up to 86.58%.

The fermentation conditions of Bacterial Strain T2013 were studied. The fermentation conditions of T2013 were investigated with single-factor experiment. In addition to, the fermentation conditions were optimized through the orthogonal test. The results showed the highest production of blue pigment was obtained on condition that fermentation time was 2d, the liquid volume was 50ml in the 250ml shake-flask, the inoculum volume was 2%, the initial value of pH was 7.6, fermentation temperature was 37°C and the speed was 150r/min.The fermentation conditions of Bacterial Strain T2013 were preliminarily determined,whichprovides a theoretical basis for the industrial production of blue pigment.

Reed Pulp was Raw Material that Pretreated by Four Methods {ultrasonic, Microwave, N, N-Dimethyl Acetamide (DMAc) and Tetrahydrofuran (THF)}. Reed Microcrystalline Cellulose (MCC) was Prepared by the Dilute Hydrochloric Acid Hydrolysis from Pretreated Reed Pulp. the Influences of Pretreatment Methods on Crystalline Type, Crystallinity and Crystallite Size of MCC were Investigated by X-Ray Diffraction (XRD). the Results Showed that the Crystallinity of MCC with Four Pretreatment Methods was 68.45%, 62.28%, 63.21% and 69.56%, Respectively. the Average Crystallite Size of MCC Prepared by Hydrolysis after Pretreated by Dmac was the Largest. whereas, the Crystal Type of MCC was Not Changed, it was still the Cellulose Type I. Comprehensive Analysis Indicated that the Effects of MCC Prepared by Hydrolysis after Pretreated by Ultrasonic were the Best.

The composition and phase transformation of oxide scale in cooling process (after hot rolling) of rolled microalloyed steels affect tribological features of rolled strip and downstream process, and the produced steel surface quality. In this study, physical simulation of surface roughness transfer during cooling process with consideration of ultra fast cooling (UFC) was carried out in Hille 100 experimental rolling mill, the obtained oxide scale was examined with SEM to show its surface and phase features. The results indicate that the surface roughness of the oxide scale increases as the final cooling (coiling) temperature increases, and the flow rate of the introduced air decreases. The cracking of the surface oxide scale can be improved when the cooling rate is 20 °C/s, the strip reduction is less than 12 %, and the thickness of oxide scale is less than 15 μm, independent of the surface roughness. A cooling rate of more than 70 °C/s can increase the formation of retained wustite and primary magnetite precipitates other than the precipitation of α-iron. This study is helpful in optimising the cooling process after hot rolling of microalloyed steels to obtain quality surface products.

Salt lake brine resource is one of the strategic resources in the western of China. Phase equilibria and phase diagrams are the theoretic foundation for the exploitation of salt lake brine resources. Hence, studies for the stable and metastable phase equilibria of lithium-containing salt-water systems are of the great importance for the development of salt lake brine resources. In this paper, the stable and metastable phase equilibria of lithium-containing salt-water systems were summarized, and the problems existed at present and the new trends in the future are also discussed.

Power transmission line monitoring is a general appellation of automated monitoring and scientific management for power transmission line by advanced techniques, and it’s an important basis for achieving smart grid. Its data transmission system is divided into access network and data network, the access network consists of a variety of terminals, tower nodes and aggregation nodes, which includes on-site and remote networks. The application of flexible and reliable network would guarantee to achieve a high-speed, reliable and transparent data transfer between master station and terminals in the system. According to the data transmission requirements of transmission line condition monitoring system, this paper studies the communication network technologies for access network in the perspective of private and public networks, and after a comparative analysis of these technologies, it proposes a principle of how to select reasonable communication network technologies for different application scenarios.

To date, limestone-gypsum has been the most widely used sintering flue gas desulfurization technology in China's steel industry. In order to demonstrate the application status, this paper stated the current desulfurization situation of Baosteel, Meishan Steel, Xiangtan Steel, Zhang steel. Process of limestone-gypsum obtained in these steel companies is playing an increasingly important role in sintering flue gas desulfurization, and a majority of these plants get a high desulfurization rate at more than 90%, which makes great contribution to the work of sulfur dioxide emissions. Besides, some problems of the desulfurization process in these plants are discussed and solutions are put forward to promote further development of the technology. For the prospects of the technology, it has been an inevitable trend to develop integration technology of desulfurization, denitrification and dioxin removal to meet requirements for energy saving work during the Twelfth Five-Year Plan. All these above presented in the paper will provide a basis in reality for the further development of this technology.

Temperature monitoring was done on microwave curing of epoxy resin system consisting of di-glycidyl ether of bisphenol-A(DGEBA) E-51 and curing agent 4,4’diamino-diphenyl-methane (DDM). The study shows that microwave curing of epoxy resin system is an exothermic reaction and the temperature variation during microwave processing has the obvious characteristics of “temperature increment - heat release - temperature falling”. Analysis on the infrared thermal images indicates that each moulding body has its own temperature distribution and differs from others. The non-uniform temperature distribution reveals the uneven electric field distribution in the domestic microwave oven.

At present, existing methods are difficult to analyze the Safety of Multitasking and complex timing sequence software. In order to overcome this difficulty, a new analysis method of multiple state transfer and real-time logic analysis method (MSTRT-TPN ) is proposed. This method extends the time Petri net analysis rules and proposes the concept of synchronous synthesis and sharing synthesis. It combines temporal logic and state transition, establishes software failure model. Through the model, the possibility of high-risk state of software can be analyzed. The effectiveness of the proposed method is verified through application in three protection device software which is typical safety-critical military software.

Based on maximum likelihood, research a new based on Symbol Detection (Multi-Symbol Detection, MSD) soft demodulation method of PCM/FM telemetry signals. Introduced the basic principle of the demodulation method and the implementation process, analyzed the demodulation and synchronization factors and formulate the corresponding synchronization strategies. Refereed/Peer-reviewed

Signal processing speed is an important indicator of the performance of software based phase-locked loop. Previous software uses data redundancy of phase-locked loop based on parallel processing, but the amount of redundant data lead to the introduction of computer waste of resources, reducing efficiency and other issues. Design of a parallel processing method based on data blocks and redundant data segments dual dynamic partitioning, given the dynamic data partitioning strategy. Refereed/Peer-reviewed

The asynchronous motor is converted to a model similar to DC motor to control through coordinate transformation, and adopt SPWM inverter circuit, the motor runs with load implements ideal speed and steady operation, providing appropriate speed for aerostatic guide way. Realize simulation of asynchronous motor variable frequency speed regulation system by simulink.

Transmission spectrum and reflectance spectrum have long been used to characterize gap semiconductor. Transmission spectrum can be measured very directly, but the influence of substrate absorption is often unavoidable. However, when using the reflectance spectrum measurement, the absorption of thin film, substrate absorption, and coherent interference will make the reflectance spectrum much more complicated. In this paper, Considering the absorption of thin film, substrate absorption, and coherent interference, we use the envelope curves algorithm to achieve the calculation formula of refractive index deduced from the reflectance spectrum. Through the analysis of the reflectance spectrum of Ga2O3film, we achieved thickness of the film, refractive index, extinction and absorption coefficient and dispersion constant.

Aimed at the problem that the demodulation threshold of non-coherent demodulation technology of PCM/FM telemetry system using frequency modulation in the present situation of aerospace measurement and control is higher, research a kind of multiple symbol detection based on maximum likelihood thought (Multi-Symbol Detection, MSD) demodulation method. This paper introduces the principle of multiple symbol detection and aiming at the shortcomings of the previous synchronization method, studies a kind of symbol decision process and synchronization of the combination of synchronization method. Refereed/Peer-reviewed

The hierarchically urchin-like magnetic hydroxyapatite (HAp)/Fe3O4 composites were hydrothermally fabricated and were used for the removal of Pb (II) from aqueous solutions. The morphology, composition and properties of the magnetic HAp/Fe3O4 composites were fully characterized and investigated. The results showed that the HAp/Fe3O4 composites had a 3D urchin-like hierarchical structure with Fe3O4 nanoparticles dispersed among the building units. These urchin-like composites had high surface area and good magnetic responsibility. The equilibrium removal process of Pb (II) by the composites was correlated well with the Langmuir model, resulting in the maximum adsorption capacity of 223.71 mg/g. The high adsorption capacity and good magnetic responsibility suggest that the multifunctional composites have great potentials for heavy metal ion removal.

The main purpose of this paper is the analysis of the influence of steel fiber and hybrid fiber on the ultimate shear load and failure mode of rectangular concrete beams. The results of this experiment study indicate that fibers can enhance the ultimate shear load. Hybrid fibers can change the failure mode. The mechanical behavior of beam with hybrid fibers is better than that with mono-steel fibers.

Graphene/NR composite was prepared in emulsion blending and the multilayer graphene was about 4-8 layers. Different mass fraction of this kind of graphene was mixed into NR in this work.The thermal conductivity of this compositive system was respected to be improved apparently since the high thermal conductivity of graphene. In this work, TEM(Transmission electron microscope) was used to observe the structure and morphology of the multilayer graphene. NETZSCH LFA was used to research the change of thermal conductivity with the fraction of grahene changing. DSC(differential scanning calorimetry) was used to research the structure change in the series of composites. The TEM results showed that the graphene we used is 4-5 layers. LFA had proved that the multilayer graphene has affected the thermal conductivity of matrix greatly and DSC also provided evidence to support the same views.

The paper introduces system components and working principle of the ultrahigh pressure water jet, with theoretical analysis on fluctuation characteristics of pressure booster pump flow. On the basis of the AMEsim simulation model established on various hydraulic components in the system, through a large number of simulation experiments to compare simulation curve with different parameters. Analysing the system characteristics for pressure and flow affected by some parameters such as: volume, booster pump motion control and the number of nozzles, in order to improve the system stability for pressure and flow and optimize the parameters.

In recent years, the increasing Debris flow has been drawing the geologists' attention for its massive destructive force. At present, the research on the debris flow are mainly based on comprehensive multi-factors evaluation or singlue factor qualitative anlalysis. However, all factors have the impact on the debris flow. At present, the research on the factors that foundamentally affecting the debris flow or its character is quite few. This paper use the method of stepwise discriminant analysis to minimize the correlation and repeatability between factors to ensure the selected factor can be fully represent the character of debris flow. In addition, classification is an important way to illustrate general picture of the debris flow. This paper classified the selected 6 key factors by method of FCM (Fussy C Means) to achieve the transition and evolution from general geological classification to the accurate quantitative analysis. The result of such classification will benefit the debris flow cognition and disaster prevention measures.

Ultraviolet (UV) curable waterborne polyurethane dispersions with comb branched structure were synthesized by prepolymer process. C=C bonds were incorporated into the branched chains of the polyurethane using chain extender, hence, the content of C=C bonds can be adjusted by the chain extender consumption. The chemical structure was identified by Fourier transform infrared spectroscopy (FTIR) and1H NMR. Effects of the chain extender content on the microstructure, rheological behavior, thermal property, mechanical and other properties of the UV cured films were researched.