New type of groove used to improve friction in roll forging简

A FEM model for a failed industrial example of roll forging was established to analyze the generation mechanisms of the mismatch of size and shape of two spring board.To demonstrate the formulation of these defects,the bites condition and contact status between rectangular groove and workpiece during rolling the first and second spring boards were analyzed.Then,a new oval-diamond groove combining oval groove and diamond groove was presented to eliminate these defects.By analyzing field variables under the same deformation degree,the larger friction can be obtained on the contact surface of workpiece and the oval-diamond groove.The physical experiment validates that the oval-diamond groove can eliminate these defects effectively,and the size of part is in good agreement with design requirement.     

Effect of surface treatment to inserted ring on Al–Fe bonding layer of aluminium piston with reinforced cast iron ring

In order to improve the bonding strength between piston alloys and cast iron ring of aluminum piston with reinforced cast iron ring, the different methods of the surface treatments （shot blasting and sand blasting） to the cast iron ring are experimented. The optical micrograph shows that an intermetallic layer and a ligulate shaped structure are formed between piston alloys and cast iron base ring. After sand blasting treatment, the ring surface is non-metal shiny, matte-like and has no obvious pits. The intermetallic layer thickness formed between piston alloys and cast iron is thinner and more equally distributed after sand blasting to the ring. The content of the graphite distributed the interfacial zone after the shot blasting treatment is little. With the increase of time by sand blasting, the hardness starts to slightly descend. The bonding strength of the sample by sand blasting is obviously higher than that by shot blasting and increases from 9.32 MPa to 19.53 MPa.     

Effects of magnetic fields on Fe-Si composite electrodeposition

Coatings containing Fe-Si particles were electrodeposited on 3.0wt% Si steel sheets under magnetic fields. The effects of magnetic flux density （MFD）, electrode arrangement and current density on the surface morphology, the silicon content in the coatings and the cathode current efficiency were investigated. When a magnetic field was applied parallel to the current and when the MFD was less than 0.5 T, numerous needle-like structures appeared on the coating surface. With increasing MFD, the needle-like structures weakened and were transformed into dome-shaped structures. Meanwhile, compared to results obtained in the absence of a magnetic field, the silicon content in the coatings significantly increased as the MFD was increased for all of the samples obtained using a vertical electrode system. However, in the case of an aclinic electrode system, the silicon content decreased. Furthermore, the cathode current efficiency was considerably diminished when a magnetic field was applied. A possible mechanism for these phenomena was discussed.     

Regeneration of waste activated carbon after extracting gold with steam under microwave heating： Optimization using responsesurface methodology

The technology that waste activated carbon after extracting gold is regenerated with steam under microwave heating was studied. The influence of the activation temperature, activation duration and steam flow rate on iodine adsorption value and regeneration yield of activated carbon was investigated. The response surface methodology （RSM） technique was utilized to optimize the process conditions. The optimum conditions for the preparation of activated carbon are identified to be activation temperature of 831 ℃, activation duration of 40 min and steam flow rate of 2.67 mL/min. The optimum conditions result in an activated carbon with an iodine number of 1048 mg/g and a yield of 40%, and the BET surface area evaluated using nitrogen adsorption isotherm is 1493 m2/g, with total pore volume of 1.242 cm3/g. And the pore structure of activated carbon regenerated is mainly composed of micropores and a small amount of mesopores.     

Cellular response to titanium discs coated with polyelectrolyte multilayer films

The purpose of this study was to investigate the effects ofpolyelectrolyte multilayer （PEM） coatings on the biological behavior of titanium （Ti） substrates. Collagen type I/hyaluronic acid （Col/HA） and chitosan/hyaluronic acid （Chi/HA） multilayer PEM coatings were introduced onto Ti substrates using layer-by-layer assembly. Contact angle instruments and quartz crystal microbalance were used for film characterization. The results obtained showed that both Col/HA and Chi/HA surfaces had high hydrophilicity and promoted cell adhesion in MC3T3-E1 pre-osteoblast and human gingival fibroblast cells. In addition, the synthesis of function-related proteins and gene expression levels in both MC3T3-E1 and fibroblast cells was higher for the Col/HA coating compared with the Chi/HA coating, indicating better cellular response to the Col/HA coating.     

Monitoring damage evolution of steel strand using acoustic emission technique and rate process theory

Utilizing the acoustic emission（AE） technique, an experimental investigation into the damage evolution for steel strand under axial tension was described. The damage evolution model for steel stand relating the damage evolution to acoustic emission parameters was proposed by incorporating the AE rate process theory. The AE monitoring results indicate that damages occur in both elastic and plastic phases of steel strand. In elastic phase, AE signals are mainly sent out from the micro damage due to the surface friction among the wires of steel strand, while in plastic phase, AE signals emitted from the plastic deformation of wires. In addition, the AE cumulative parameters curves closely resemble the loading curve. The AE cumulative parameters curves can well describe the damage evolution process including the damage occurrence and damage development for steel strands. It is concluded that the AE technique is an effective and useful nondestructive technique for evaluating the damage characteristics of steel strand.     

Trajectory planning and tracking control for underactuated unmanned surface vessels简

The trajectory planning and tracking control for an underactuated unmanned surface vessel（USV） were addressed.The reference trajectory was generated by a virtual USV,and the error equation of trajectory tracking for underactuated USV was obtained,which transformed the tracking and stabilization problem of underactuated USV into the stabilization problem of the trajectory tracking error equation.A nonlinear state feedback controller was proposed based on backstepping technique and Lyapunov＇s direct method.By means of Lyapunov analysis,it is proved that the proposed controller ensures that the solutions of closed loop system have the ultimate boundedness property.Numerical simulation results are presented to validate the effectiveness and robustness of the proposed controller.     

Orthogonal design and numerical simulation of room and pillar configurations in fractured stopes

Room and pillar sizes are key factors for safe mining and ore recovery in open-stope mining. To investigate the influence of room and pillar configurations on stope stability in highly fractured and weakened areas, an orthogonal design with two factors, three levels and nine runs was proposed, followed by three-dimensional numerical simulation using ANSYS and FLAC3~. Results show that surface settlement after excavation is concentrically ringed, and increases with the decrease of pillar width and distances to stope gobs. In the meantime, the ore-control fault at the ore-rock boundary and the fractured argillaceous dolomite with intercalated slate at the hanging wall deteriorate the roof settlement. Additionally, stope stability is challenged due to pillar rheological yield and stress concentration, and both are induced by redistribution of stress and plastic zones after mining. Following an objective function and a constraint function, room and pillar configuration with widths of 14 m and 16 m, respectively, is presented as the optimization for improving the ore recovery rate while maintaining a safe working environment.     

Desulfurization ability of refining slag with medium basicity

The desulfurization ability of refining slag with relative lower basicity （B） and Al2O3 content （B = 3.5-5.0; 20wt%-25wt% Al2O3） was studied. Firstly, the component activities and sulfide capacity （Cs） of the slag were calculated. Then slag-metal equilibrium experiments were carried out to measure the equilibrium sulfur distribution （Ls）. Based on the laboratorial experiments, slag composition was optimized for a better desulfurization ability, which was verified by industrial trials in a steel plant. The obtained results indicated that an MgO-saturated CaO-Al2O3-SiO2-MgO system with the basicity of about 3.5-5.0 and the Al2O3 content in the range of 20wt%-25wt% has high activity of CaO （αCaO）, with no deterioration of Cs compared with conventional desulfurization slag. The measured Ls between high-strength low-alloyed （HSLA） steel and slag with a basicity of about 3.5 and an Al2O3 content of about 20wt% and between HSLA steel and slag with a basicity of about 5.0 and an Al2O3 content of about 25wt% is 350 and 275, respectively. The new slag with a basicity of about 3.5-5.0 and an Al2O3 content of about 20wt% has strong desulfurization ability. In particular, the key for high-efficiency desulfurization is to keep oxygen potential in the reaction system as low as possible, which was also verified by industrial trials.     

Production of HfO2 thin films using different methods： chemical bath deposition,SILAR and sol-gel process

Hafnium oxide thin films （HOTFs） were successfully deposited onto amorphous glasses using chemical bath deposition, successive ionic layer absorption and reaction （SILAR）, and sol-gel methods. The same reactive precursors were used for all of the methods, and all of the films were annealed at 300℃ in an oven （ambient conditions）. After this step, the optical and structural properties of the films produced by using the three different methods were compared. The structures of the films were analyzed by X-ray diffTaction （XRD）. The optical properties are investigated using the ultraviolet-visible （UV-VIS） spectroscopic technique. The film thickness was measured via atomic force microscopy （AFM） in the tapping mode. The surface properties and elemental ratios of the films were investigated and measured by scanning electron microscopy and energy-dispersive X-ray spectroscopy （EDX）. The lowest transmittance and the highest reflectance values were observed for the films produced using the SILAR method. In addition, the most intense characteristic XRD peak was observed in the diffraction pattern of the film produced using the SILAR method, and the greatest thickness and average grain size were calculated for the film produced using the SILAR method. The films produced using SILAR method contained fewer cracks than those produced using the other methods. In conclusion, the SILAR method was observed to be the best method for the production of HOTFs.     

Free clustering optimal particle probability hypothesis density（PHD） filter

As to the fact that it is difficult to obtain analytical form of optimal sampling density and tracking performance of standard particle probability hypothesis density（P-PHD） filter would decline when clustering algorithm is used to extract target states,a free clustering optimal P-PHD（FCO-P-PHD） filter is proposed.This method can lead to obtainment of analytical form of optimal sampling density of P-PHD filter and realization of optimal P-PHD filter without use of clustering algorithms in extraction target states.Besides,as sate extraction method in FCO-P-PHD filter is coupled with the process of obtaining analytical form for optimal sampling density,through decoupling process,a new single-sensor free clustering state extraction method is proposed.By combining this method with standard P-PHD filter,FC-P-PHD filter can be obtained,which significantly improves the tracking performance of P-PHD filter.In the end,the effectiveness of proposed algorithms and their advantages over other algorithms are validated through several simulation experiments.     

Dielectric,piezoelectric, and ferroelectric properties of lanthanum-modified PZTFN ceramics

Specimens of Pb1-1.5xLax（Zr0.53 Ti0.47）1-y-zFeyNb2O3 （x = 0, 0.004, 0.008, 0.012, and 0.016, y = z = 0.01） （PZTFN） ceramics were synthesized by a semi-wet route. In the present study, the effect of La doping was investigated on the structural, microstructural, dielectric, piezoelectric, and ferroelectric properties of the ceramics. The results show that, the tetragonal （space group P4mm） and rhombohedral （space group R3c） phases are observed to coexist in the sample at x = 0.012. Microstructural investigations of all the samples reveal that La doping inhibits grain growth. Doping of La into PZTFN improves the dielectric, ferroelectric, and piezoelectric properties of the ceramics. The hys- teresis loops of all specimens exhibit nonlinear behavior. The dielectric, piezoelectric and ferroelectric properties show a maximum response atx 〉 0.012, which corresponds to the morphotropic phase boundary （MPB）.     

Fluidized bed coating efficiency and morphology of coatings for producing Al-based nanocomposite hollow spheres

Abstract： We performed fluidized bed coating ofAl-based nanoeomposite powder-binder suspensions onto polymer substrates. The effects of the type and amount of the binder and nanoparticle additive on the coating process efficiency and coating characteristics were investigated. The efficiency decreased from 52% to 49% as the processing time increased from 15 to 20 min. However, the amount and thickness of the coating also increased as the processing time and amount of the binder were increased. The addition of nanoparticles to the system decreased the thickness of the coating from 222 to 207 μm when polyvinyl alcohol （PVA） was used as a binder. The suspension containing 3wt% R-4410 binder exhibited the greatest efficiency of 60%.     

A ternary TiO2/WO3/graphene nanocomposite adsorbent： facile preparation and efficient removal of Rhodamine B

Ternary TiO2/WO3/graphene （TWG） nanocomposites were prepared by a facile salt-ultrasonic assisted hydrothermal method. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and nitrogen adsorption--desorption. Both anatase TiO2 and orthorhombic WO3 formed in the nanocomposites, along with a highly disordered overlay of individual graphene nanosheets. Polyhedral and spherical TiO/and WO3 nanoparticles of uniform size 10-30 nm were densely anchored to the graphene sheets. The maximum specific surface area of the products was 144.59 m2·g^-1. The products showed clear abilities for the removal of Rhodamine B in the absence of illumination. Furthermore, the adsorption activity of the products exhibited only a slight decrease after three successive cycles. The results demonstrate that the ternary nanocomposites could be used as a high-efficiency adsorbent for the removal of environmental contaminants.     

Effects of the microstructure of twin roll cast and hot rolled plates on the surface quality of presensitized plates

The effect of the microstructure of plates fabricated both in the traditional process, involving casting, hot rolling and cold rolling （HR）, and in the novel twin roll casting ＋ cold rolling （TRC） process on the surface quality of presensitized （PS） plates was analyzed by optical microscopy （OM）, scanning electron microscopy （SEM）, and energy-dispersive X-ray spectroscopy （EDXS）. The formation of pores on the surface of the electrolyzed HR plate could be attributed to the presence of approximately 1-μm-sized large Al-Fe precipitates in the HR plate compared to the smaller precipitates in the TRC plate. Moreover, residual graphite lubricants used during the TRC process were entrapped on the surface of the TRC plate during the subsequent rolling process. The entrapped pollutants tended to further deteriorate the formation of pores on the surface of the TRC plate, and no residual carbon was detected on the surface of the HR plate. Furthermore, the surface quality of the TRC plate can be improved by surface cleaning before the cold rolling process, which could dramatically lower the residual graphite on the surface.     

Large-scale two-dimensional nonlinear FE analysis on PGA amplification effect with depth and focusing effect of Fuzhou Basin

Based on the explicit finite element（FE） method and platform of ABAQUS,considering both the inhomogeneity of soils and concave-convex fluctuation of topography,a large-scale refined two-dimensional（2D） FE nonlinear analytical model for Fuzhou Basin was established.The peak ground motion acceleration（PGA） and focusing effect with depth were analyzed.Meanwhile,the results by wave propagation of one-dimensional（1D） layered medium equivalent linearization method were added for contrast.The results show that：1） PGA at different depths are obviously amplified compared to the input ground motion,amplification effect of both funnel-shaped depression and upheaval areas（based on the shape of bedrock surface） present especially remarkable.The 2D results indicate that the PGA displays a non-monotonic decreasing with depth and a greater focusing effect of some particular layers,while the 1D results turn out that the PGA decreases with depth,except that PGA at few particular depth increases abruptly; 2） To the funnel-shaped depression areas,PGA amplification effect above 8 m depth shows relatively larger,to the upheaval areas,PGA amplification effect from 15 m to 25 m depth seems more significant.However,the regularities of the PGA amplification effect could hardly be found in the rest areas; 3） It appears a higher regression rate of PGA amplification coefficient with depth when under a smaller input motion; 4） The frequency spectral characteristic of input motion has noticeable effects on PGA amplification tendency.     

Bonding characteristics of the Al2O3-metal composite coating fabricated onto carbon steel by combustion synthesis

The fabrication of an alumina-metal composite coating onto a carbon steel substrate by using a self-propagating high-temperature synthesis technique was demonstrated. The effects of the type and thickness of the pre-coated layer on the binding structure and surface qual- ity of the coating were systematically investigated. The macrostructure, phase composition, and bonding interface between the coating and the substrate were investigated by scanning electronic microscopy （SEM）, X-ray diffraction （XRD）, and energy-dispersive X-ray spectrometry （EDS）. The diffraction patterns indicated that the coating essentially consisted of α-Al2O3, Fe（Cr）, and FeO-Al2O3. With an increase in the thickness of the pre-coated working layer, the coating became more smooth and compact. The transition layer played an important role in enhancing the binding between the coating and the substmte. When the pre-coated working layer was 10 mm and the pre-coated transition layer was 1 ram, a compact structure and metallurgical bonding with the substrate were obtained. Thermal shock test results indicated that the ceramic coating exhibited good thermal shock resistance when the sample was rapidly quenched from 800℃ to room temperature by plunging into water.     

Mechanism of electro-hydraulic exciter for new tamping device简

A new tamping device which is driven by an electrohydraulic exciter was proposed to overcome the limitations of mechanically driven devices.The double-rod oscillation cylinder drives the tamping arm to realize vibration.A new spin valve was designed in order to fulfill dynamic state requirements of the oscillation cylinder.Parametric analysis was carried out by establishing mathematic model.Then,the relationships among the structure of valve port and the frequency,amplitude,output shock force of the cylinder were researched.An experimental device of the electrohydraulic exciter was established to validate the theoretical results.The signals were acquired by AVANT dynamic signal analyser of vibration.The results show that new tamping device can satisfy all kinds of complex working conditions with the flexible adjustment of frequency and amplitude.     

放射性廃棄物量を低減するための低放射化材料の開発

When nuclear plants will reach to decommission stage, a huge amount of concrete should be disposed as radioactive waste. So design methodology for reinforced concrete of nuclear power plants to reduce radioactive wastes in decommission phase has been developed. To realize this purpose （1）Development of raw materials database of cements, aggregates and steel bars on concentration of radioactive target elements, （2）trial production of low activation cement and steel bars based on the material database, and （3）development of tools for estimation and prediction of the amount of radioactive elements in reactor shielding walls have been carried out.
Manufactu cements, low-a crete. After th ring tests by etivation addi at, we devel mixing together with low-activation aggregate, low-activation tives, etc, have been performed to develop low-activation conoped various types （1/10, 1/20, 1/30, …, 1/1000, 1/3000, and 1/10000） of low activation concrete composed of low activation raw materials as very useful shielding material in a nuclear facility. The term＂1/10 of low-activation concrete＂ denotes that the activity reduction rate to ordinary concrete is designed to be 1/10. By adopting some suitable types of low-activation concrete, most of the shielding concrete around ABWR and APWR are classified below clearance level on decommissioning.
To reduce the radioactive concrete, the most effective methodology is not to use the materials of high radio-nuclide content such as coal ash and blast furnace slag, and to use limestone as additives or aggregate. However, concrete uses Portland cement for hardening, therefore, it is difficult to reduce the amount of radioactive concrete unless radio-nuclide content in cement is reduced. So in this study, we tried to develop the new type of low-activation cement by reducing of radio-nuclide as europium and cobalt.     

High-temperature performance prediction of iron ore fines and the ore-blending programming problem in sintering

The high-temperature performance of iron ore fmes is an important factor in optimizing ore blending in sintering. However, the application of linear regression analysis and the linear combination method in most other studies always leads to a large deviation from the desired results. In this study, the fuzzy membership functions of the assimilation ability temperature and the liquid fluidity were proposed based on the fuzzy mathematics theory to construct a model for predicting the high-temperature performance of mixed iron ore. Comparisons of the prediction model and experimental results were presented. The results illustrate that the prediction model is more accurate and effective than previously developed models. In addition, fuzzy constraints for the high-temperature performance of iron ore in this research make the results of ore blending more comparable. A solution for the quantitative calculation as well as the programming of fuzzy constraints is also introduced.