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Excess bisphenol A (BPA) is a pollutant of concern in different water sources. In this work, magnetic illite clay-composite material (Fe3O4@illite) was synthesized via the coprecipitation method by loading Fe3O4 nanoparticles (nano-Fe3O4) onto the surfaces of illite clay. Results from different characterizations showed that nano-Fe3O4 was embedded into illite clay nanosheets and existed on the surfaces of illite clay, thereby reducing the degree of agglomeration and improving dispersibility. The catalytic BPA degradation of Fe3O4@illite and nano-Fe3O4 confirmed the superior performance of Fe3O4@illite compared with that of nano-Fe3O4. The optimum operating parameters for degradation were 0.3 mL of H2O2 at pH of 3 in the presence of Fe3O4@illite, which provided a maximum degradation capacity up to 816, 364, 113, and 68 mg/g for epoxy BPA concentration of resin wastewater (266 mg/L), synthetic wastewater (80 mg/L), Hefei City swan lake (25 mg/L), and Hefei University lake wastewater (14.94 mg/L), respectively, in 180 min reaction time. The degradation data conformed to the pseudo-first-order kinetic model. The degradation pathways and mineralization study revealed that the adsorption-Fenton-like reaction was the principal mechanism that demonstrated 100% degradation efficiency of Fe3O4@illite even after nine successive runs. The regeneration and reusability tendency analysis ensured that Fe3O4@illite can be easily separated by using magnets. Therefore, Fe3O4@illite composite with H2O2 Fenton-like technology was a promising method for BPA degradation.

Research on the lightweight issue of DC-link is an important direction in modern AC drive electric locomotive. Canceling LC filter circuit is an important way to achieve the goal of lightweight. Therefore, this paper focuses on single-phase pulse rectifier without LC filter circuit. The generation mechanism of DC voltage ripple and network-side current harmonics in grid-side converter is derived. Then, aiming to eliminate the current harmonics, the N-order notch filter and PR controller are introduced to the double-loops controller. The loop of voltage outer controller with N-order notch filter can filter out the ripple of DC-side voltage effectively without affecting the dynamic performance of the controller system. Meanwhile, the loop of current inner controller with PR controller can achieve zero steady-state error control to both the fundamental and harmonic current, and can suppress the low order harmonics in the line current effectively. Analysis shows that replacing the original L2C2 filter circuit with software controller is feasible. Finally, the validity and effectiveness of the proposed scheme are verified in computer simulation.

The calculation model of motor operating on asymmetric rotor was defined taking a traction squirrel-cage induction motor in Electric Multiple Units (EMU) as sample. Based on the basic principle of numerical analysis, magnetic field in the motor and current in the bar were calculated for both normal motor and broken-bar motor by using the Jmag software, and both the magnetic field variation and current variation in the bar were summed up. According to the EMU’s special control methods, the motor with two broken bars was simulated at different work point, and the characteristic component variation was presented. The works in this paper lay the foundation of diagnosis method for broken rotor bar fault, especially for traction motor in EMU.

Due to IGBT open-circuit fault of CRH2 EMU’s traction inverter, a method of its fault diagnosis with the three-phase current signals as detection objects is conducted. By applying the wavelet analysis, three-phase current signals are decomposed for four times. With the coefficients of each layer obtained, the energy values of layers are calculated as well as the vectors corresponding to failure modes. According to the vectors regarded as input and the expected output, a BP neural network is established. Through training the network, the parameters of network can be defined. In addition, to test and evaluate the performance of network, certain noise is added to the three-phase current signals. Simulation results show it is feasible for the fault diagnosis of traction inverter.

Centrifugal modeling technology has been applied to geotechnical engineering for more than half a century. It has been an important and indispensible means to simulate the geotechnical behavior because it has the same material, the similar boundary conditions and the same stress level. And it is also commonly used in tunnel-related research. Centrifugal tests of pipe-roof and small pipe grouting in tunnel were analyzed, the important effects of centrifugal tests on preliminary support of the tunnel were also emphasized. Problems often met in model tests of tunnelling were solved, such as structure model, modeling soil, preliminary support model and general programming of experiment proposal. The future development of centrifuges in tunnelling is also presented.

Diseases such as segment cracks, damage, dislocation, water leakage often occur during the construction and operation process of shield tunnel, which will threaten the safety of running trains and shorten the maintenance cycle and service life. Based on previous research on shield tunnel diseases, the paper makes an analysis of the detection methods, causes of diseases, evaluation and repairment. Combining with the personal understanding of practical projects, the authors put forward some problems about the current research.

This paper based on Chaoyang tunnel by bench method excavation, using the finite element numerical simulation method, simulates the surrounding rock displacement of soft rock tunnel and the stress characteristics of supporting structure to get the various stages of tunnel surrounding rock stress, strain and the internal force changes of tunnel supporting structure. After the analyses of the numerical simulation results and field monitoring measurement data, the safety and rationality of the method are determined. The research provides certain reference for highway tunnel design and construction.

Aiming at the difficulties to establish dynamic models of industrial robots, a novel fuzzy PID controller based on product strategy was presented. Membership degrees was determined according to position error and error change. Meanwhile, parameters of the fuzzy-PID controller would be tuned by the varied factors calculated from the membership degrees based on product strategy. Considering disturbance of friction, feedforward based on Stribeck model was introduced. Compared with traditional PID controller, experiment of manipulator demonstrates better effectiveness and robustness of the controller. The new controller keeps tracking error within 0.4%.

The reduction and distillationcontainer in titanium-sponge-production is of great concern. In order to get access to a highly efficient vessel which can produce sponge titanium of high quality, a new structureof new material was brought forward in this paper. This new structure, with doublelayers, inner layer of carbon steel and outer layer of stainless steel, was a substitute for traditional single-layer stainless steel container. This new optimization method of 12t container brought in the paper can reduce the impurities in the sponge titanium lump andincrease the times of the container to use.Of cause, it has a great improvement in yield per unit time. For the purpose of improving the reliability of this new optimization structure, temperature and stress field was established and simulated by an integrated FEM/FEM system based on ANSYS. This theory, therefore, can be one of the solutions to the development of titanium-sponge-production equipments by means of the thermal stress field analysis.

Combined with highway tunnel monitoring measurement work of Bijia Mountain, the contents and methods of site monitoring and the analyzing methods for collected data of highway tunnel construction were studied. A comparative way was used to analyze the different curves of displacement with time on the two typical segments of ground settlement convergence and vault crown settlement. The result shows that the site monitoring curves of displacement with time can be divided into normal type and abnormal one. This article puts forward some feasible suggestions about how to guide the safe construction through the two types of curve. The aim of this article is to explore the changing of the abnormal curve before the dangerous accident occur, and give the causes of the reasonable analysis after collapse happened.

A novel control scheme based on an improved RBF neural network and PID control method is proposed. When used the RBF network in the PID controller, if RBF network provides the parameter to revise PID while it does not have training finished, the controller will oscillated or even to diverge. As the structure is more complex, and the adjustment speed is slower, the improvements are made to the standard RBF neural network trained algorithm. Uses the matrix operation substitute the iterative algorithm, may avoid the above question effectively. Finally, choosing a certain type of PID controller, the improved RBF neural network algorithm is used to design the control law for control command tracking, the simulation results show that the improved RBF neural network algorithm can avoid oscillated and diverge.

To understand the stressed characteristic of fault rupture zone under high hydraulic pressure, based on the F3 fault of Guanshan tunnel the software 2D-FLAC is adopted to found the fluid-solid coupling numerical model of ground water seepage and evolution in the process of tunnel structure in fault rupture zone under high hydraulic pressure and analyze the mechanical character of tunnel structure in three schemes of whole block, free discharge and limit discharge. The result shows that in the whole block condition, the partial seepage of ground water happened and the lining thickness should be more than 60cm; Regardless of water pressure, the rock is damaged at a large range, and the minimum safety factor of the lining structure meet the tunnel design standard; In the limit discharge condition, the grouting reinforced ring makes the effect of limiting drainage and keeping the tunnel’s stability in the construction. The tunnel drainage gets smaller with the increase of grouting ring’s thickness and the decrease of grouting ring’s penetration parameter; setting the drainage system can decrease the hydraulic pressure at the back of lining as well as grouting and water blocking.

With heat conduction differential equation of the transient temperature field, Galerkin method is adopted to deduce the three-dimensional finite element formula; based on the test result of temperature field, the actual temperature of the environment inside the tunnel shall be exerted on surface of the second lining concrete as load, thus establish the three dimensional computation model of the temperature field of tunnel in cold region. Next, on basis of the model, numerical analysis on cross section of burial depth and longitudinal direction of tunnel in cold region with and without thermal insulating layer, so as to provide theoretical basis for thickness and longitudinal length of thermal insulating layer laid in tunnel of cold region.

Based on a practical engineering, considering the characteristics such as shallow,weaking surrounding rock, large span, double-arch of the tunnel, the stress and strain of surrounding rocks, support structure and mid-wall were analyzed by FEM for different excavating procedure. The simulation results were compared with in-situ monitoring results. The crown settlement and convergence displacement are divided two obvious increasing stages. Surrounding rock upper and under the mid-wall generate bigger plastic strain and should be strengthened. Temporary support of the pilot bears bigger load and should be reinforced. Bearing bigger horizontal direction tensile stress and uneven load, the bottom of mid-wall must have enough reinforcing steel bar or employ augment foundation. The analysis results provide a scientific basis and technical guidance for the construction optimization of the tunnel constructed by three-pilot excavation method.

In order to analyze the stability of the tunnel construction of the fault fracture zone, by adopting the three-dimensional finite element, the paper analyzed the construction process of the Qingshashan Tunnel passing through the F5 fault fracture zone, and the rules and characteristics of deformation, stress distribution and its rules of changes, and the distribution range of the failure zone of the surrounding rock in the construction process, which would have important significance in guiding tunnel construction. Studies have shown that the three-dimensional finite element has a broad application prospect in tunnel projects.

Based on similarity theory, the systemic analysis for the distribution characteristics of tunnel temperature field in two different working conditions of having no thermal insulation and installing PU as insulator is progressed by using manufactured model test platform in order to realize the tunnel temperature field rule in cold regions with or without thermal insulation and the influence of thermal insulation layout pattern on insulating effect. The results show that the temperature variation conforms to the “tunnel freeze-thaw circle” theory without thermal insulation, and the surrounding rock maintains negative temperature all the time in the low temperature environment; the internal temperature field of surrounding rock plays a decisive role on the surface temperature of surrounding rock, which keeps above 0°C after the layout of thermal insulation with appropriate material and thickness.

At present, the new Austrian tunneling method is basically used as the theoretical guidance for domestic tunnel design, which shows that the primary support is not progressed by durability design in the light of service life in the practical work generally acting as the temporary support structure during the period of construction. After the long-term tunnel operation, owing to the erosion of groundwater and the changes of internal stress and external load of surrounding rock, the reinforced of primary support system will be rusted; the bolt, grille arch frame and I-beam will be partially invalidated; the stress of tunnel structure system will be readjusted gradually from the original load-bearing state with dominant position of primary support into the load-bearing state by secondary lining. The Long-term safety analysis refers to the analysis of secondary lining internal force and safety coefficient by load structure model, and the long-term safety analysis of Qingshashan tunnel which is in season frozen zone with complex geological conditions is very necessary.

Based on practice road tunnel engineering in Gansu province and near areas in west china, the main construction technology and emphasis of quality monitoring of waterproof and drainage of loess road tunnel are analyzed. Requirements of waterproof and drainage construction and methods of quality monitoring are obtained. Principle of design for waterproof and drainage in highway tunnels construction is provided. The analysis results provide technical guidance for the waterproof construction optimization of loess tunnels.

An n-body Ni–Nb–Ta potential is constructed to conduct molecular dynamics simulations using 129 solid solution models with various compositions. Comparing the relative stability of solid solutions versus their disordered counterparts, simulations determine two critical solid-solubility lines, which define a region in the composition triangle. If an alloy is located inside the defined region, a disordered state is energetically favored; if it is located outside, a crystalline solid solution is preserved. The region is therefore named as the metallic glass-forming region.

Enlargement of electrode face diameter in resistance spot welding was the main factor that led to undersize nugget diameter. A mathematics model was established to estimate electrode face diameter by applying the characteristic that servo gun can detect axial wear online but not equip additional measurement apparatuses. Firstly the precision of servo gun was compensated to assure it can meet the requirement of axial wear measurement online. Then the model was established to estimate electrode face diameter online by a minimum amount of experiment data to determine the numerical constant in the model. To verify the model, electrode life tests for welding different galvanized steels were carried out. It was shown that estimation results of the model agreed well with the experiment results and spot welding the steels with higher electrode wear rate would result in a shorter electrode life