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Various plasma electrolytic oxidation (PEO) ceramic coatings were fabricated on aluminum in the electrolytes with different concentrations of Na2SiO3·9H2O. The morphology of fractured cross-section and coating/substrate (C/S) interface, phase compositions, and corrosion behavior of these ceramic coatings were characterized employing field emission scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS), X-ray diffractometer (XRD), potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The results showed that adding Na2SiO3·9H2O in the electrolyte could reduce the decrease amplitude of the voltage-time curve, and it can affect the types of the anodic film before the beginning of plasma discharges. A novel phenomenon was recorded as PEO treatment was carried out in the electrolyte with 1.85 g l−1 Na2SiO3·9H2O that the substrate was first covered by a barrier-type anodic film, and then a porous-type anodic film appeared after the barrier-type anodic film was broken down. The anodic film continued to grow for a long duration in the PEO process after being broken down. Characteristics of PEO ceramic coatings with a similar thickness acquired in various electrolytes were also evaluated. XRD results indicated that these ceramic coatings of similar thickness were mainly composed of α-Al2O3 and γ-Al2O3, and the α-Al2O3 proportion decreased with increasing Na2SiO3·9H2O concentration. The electrochemical data showed that the corrosion resistance of these PEO ceramic coatings of similar thickness decreased by adding Na2SiO3·9H2O in the electrolyte.

Plasma electrolytic oxidation (PEO) of Al was carried out in dilute alkaline sodium tripolyphosphate (Na5P3O10) electrolyte. Surface and cross-section morphologies, elemental and phase compositions were characterized by scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS) and X-ray diffractometer (XRD). The results revealed that a severe thinning of the anodic film resulted in the voltage decrease at the initial stage of the PEO process. Porous-type anodic film with uniform pore diameter were fabricated at the initial stage of PEO process. Subsequently, detachments and cracks took place on the anodic films, and served as weak regions occurring dielectric breakdown preferentially due to the concentration of electric current at these sites. Two origins of PEO coatings, the transformation of anodic films and the normal generation of PEO coatings through the plasma discharges, were proposed. The results also indicated that P element mainly participated in the anodic oxidation and existed as amorphous phase in the inner side areas of anodic films except the barrier layer. Based on the analyses of the microstructure evolution and the chemical composition, a schematic of coating growth mechanism was proposed in the end.

A plasma electrolytic oxidation (PEO) coating was fabricated on AA1060 alloy in an alkaline sodium hexametaphosphate ((NaPO3)6) electrolyte. The growth characteristic of the PEO coating was investigated by means of a substrate-detachment technique, Scanning electron microscope (SEM) equipped with energy dispersive spectrometry (EDS), X-ray photoelectron spectrometer (XPS), X-ray diffractometer (XRD) and Mott-Schottky analysis. The results showed that an ordered and porous anodic aluminum oxide (AAO) film was formed at the anodic oxidation stage by the influence of (NaPO3)6 in the electrolyte, and the microstructure of the AAO film induced the plasma discharge events to initiate inside the AAO film. The Mott-Schottky analysis showed that the PEO coated samples were all represented n-type semiconducting behavior. The microstructures of detached coatings showed that the coating/substrate interfaces formed at the anodic oxidation stage and sparking stage consist of numerous hemispherical cap structures, but with different sizes. It was also revealed that the inward growth of the hemispherical cap structures is dependent on the diffusion of oxygen from the electrolyte or plasma gases to substrate, and P atoms mainly exist in the amorphous phase of the PEO coating.

Plasma electrolytic oxidation (PEO) coatings were prepared on AA1060 alloy substrate by a galvanostatic regime in an alkaline sodium hexametaphosphate ((NaPO3)6) electrolyte, and the influences of ...

Coatings prepared by different electrolyte additives were investigated on AZ31 magnesium alloy by plasma electrolytic oxidation. In this study, scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction analysis were employed to assess the morphologies, chemical and phase compositions of the plasma electrolytic oxidation (PEO) coatings, respectively. Furthermore, electrochemical impedance spectroscopy was used to evaluate the corrosion behavior of the composite coating. The investigation of the effect of electrolyte additives in the base electrolyte showed that the PEO specimens exhibit different surface and cross-sectional morphologies, and phase compositions. The results showed that SiO32&minus, was conducive to the growth of the ceramic layer, and the ceramic layer developing in the electrolyte which contained AlO2&minus, showed a typical double-layer structure. The corrosion resistance of coating formed in a phosphate bath was higher than that of the coating formed in silicate bath and coating formed in an aluminate bath. Moreover, the corrosion resistance of the coating formed in the fluoride bath was the highest.

In the current investigation, plasma electrolytic oxidation (PEO) ceramic coatings on Al are galvanostatically synthesized at various processing stages in an alkaline silicate system. The resultant coatings are systematically surveyed in terms of the following respects: the applied voltage and surface sparking evolution over the studied course of PEO are recorded by the signal acquisition system and the real time imaging, respectively; the phase constitution, the surface morphology, polished cross section of the coated specimens, the fractured cross section and coating/substrate interface of the detached coatings are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) assisted with energy-dispersive X-ray spectrometer (EDS), respectively. In particular, the coatings detached by an in-house developed electrochemical way disclose the coating microstructure in a new angle, which allows the cross section and the coating/substrate interface to come clearly into focus. The microstructure evolution of the oxide ceramic coatings and the correspondences among the characteristic microstructures of the free surface, the fractured cross section and the coating/substrate interface are presented and discussed. Further, based on the present PEO coating microstructure, a model of the coating growth that evolves over time is proposed.

A CuO-Al2O3 composite coating was obtained by an AC deposition and a followed secondary MAO treatment in an acidic copper sulfate electrolyte and an alkaline sodium hexametaphosphate electrolyte. Analyzes on phase and elemental composition and microstructure showed that a continuous CuO layer was formed on the top of the original MAO coating. EIS test suggested that after a secondary MAO treatment for 1 min, the samples obtained by AC deposition for 5 min had the best corrosion resistance, because of the barrier of CuO layer to the NaCl solution.

Micro-arc oxidation (MAO) coatings were prepared on Al substrate in alkaline sodium hexametaphosphate, sodium silicate and sodium aluminate electrolytes, the breakdown voltage and responsive current respectively decreased and increased with increasing the electrolyte concentration. The behavior of electrolyte during MAO processes was analyzed and discussed based on the data of the coating microstructure, elemental and phase composition, and the carrier density and impedance of the coating. The behavior can be explained by a mechanism in which anions incorporated into the coating reduced the anion vacancies, thus reducing the carrier density and improving the impedance.

Ceramic coatings were performed on aluminum through plasma electrolytic oxidation (PEO) in a Na5P3O10 solution with various concentrations of NaOH. It was revealed that the concentration of NaOH affected the types of anodic films and the activity of plasma discharges. Emphatic investigation was performed on the coatings fabricated in the electrolyte with addition of 1 g L−1 NaOH, focusing on the coating microstructure evolution and coating corrosion resistance. Some coatings were detached from the substrate, showing that the oxide particles on the anodic film C/S interface underwent profile variations from hemisphere to polygon, and its interpore distance decreased over time. The formations of pores of anodic films and plasma discharge of the PEO coatings were both easy to occur around the existing pores and the existing discharge channels. Fractured cross-section showed that a pancake-like structure corresponded to a discharge channel, a cavity, and a barrier layer protrusion whose area was similar to that of the corresponding pancake-like structure. The data of potentiodynamic polarization measurements showed that the sample treated with PEO for 10 min possessed the lowest icorr value of 4.97E-8 A cm−2, the most positive Epit value of −0.63 V, and the highest Rp value of 2.66E5 Ω cm2. EIS data of 10 min sample exhibited the highest R2 value of 1.61E6 Ω cm2, demonstrating the best corrosion resistance among these samples.

The mechanism of cable crosstalk involving what and how does the factors affect the level of crosstalk is introduced in detail. A transmission line model for predicting crosstalk between power cable and the other wires nearby with common reference ground based on multiconductor transmission theory (MTL) is developed. Crosstalk among circuit configurations when the victim cables with load terminations are different types is analyzed and simulated. Models where the types of the victim lines are shielded coaxial cable, shielded twisted pair and unshielded twisted pair are simulated. It is found that the shielding can provide an attenuation of about 50dB than the unshielded cables. In addition, the condition of multi-cable coupling is simulated and some thoughts are brought out to inspire more detailed study. Finally, some measures are suggested to suppress the crosstalk between cables according to the two-type of coupling mechanism (inductive coupling and capacitive coupling).

By examining the compressive and flexural strength of composite and using scanning electron microscopy (SEM), we analyzed the influence of sodium hydroxide on the properties of FGD gypsum and slag composite materials and discussed the influence of sodium hydroxide on the setting time and mechanical strength of the composite materials and presented the action mechanism of sodium hydroxide as a stimulator. The results show that when the content of sodium hydroxide was percent of 0.25, the maximal strength of FGD gypsum-slag composite materials was reached.

When larger scale of small hydropower and wind power exist in power system, the traditional reserve capacity algorithm is no longer applicable at the same time of reducing the carbon emission. Aiming at the volatility and non-regulatory of small hydropower and wind power, considering the forecast error of small hydropower, wind power and load,the unit outage rate and other factors, combined with the actual operation parameters of one regional power system in Southwest of China, the wind-hydro – thermal power coordinated operation of multiple objective function optimization calculation model of reserve capacity is established. Using the weighted coefficient method of unified objective method, it transforms the multi-objective optimization problem into a single objective optimization one. Applying the exterior penalty function method, the constrained optimization problem is changed into a non-constrained optimization one. The improved particle swarm optimization algorithm is got by introducing the particle concentration cognition into traditional particle swarm optimization algorithm. The simulation results verify the validity of the model. To Compare them under different strategies, this method can get less fuel expenses of thermal power units in the case of lower loss of load probability (LOLP).With the small hydropower and wind power output size to optimize the spinning reserve capacity. The model and the algorithm are helpful for drawing up optimization strategies of the reserve capacity in those regions in which larger scale small hydropower and wind power exists.

As the development of the slurry pipeline transportation system complexity and intelligent,it is more difficult to establish the reliability of the system.This pape take advantage of the descriptions of dynamic systems of stochastic failure petri net,applying in the field of slurry pipeline transport system reliability analysis.At same time,with the combination of Markov theory, it established the model of the hydraulic system reliability analysis.The feasibility and availability of the method is proved through an example of hydraulic system of slurry pipeline transportation.

This paper begins with analyzing the hazard of system harmonics and proposing the effectiveness of active power filter (APF) in harmonic wave inhibition. Against the background of single-phase parallel type of APF, its working principle is introduced and its mathematical model is built. Next, analyzed in details is the single-phase parallel type of APF double loop control system based on outer voltage loop and inner current loop, with the specific design procedure of PI control parameters of outer voltage loop and inner current loop presented. Finally, through MATLAB simulation, the designed system control parameters undergo verification. The simulation result indicates such single-phase parallel type of APF based on the double loop PI controller with outer voltage loop and inner current loop can ensure stability of the DC bus voltage and make effective compensation for harmonics over the mid-and low-frequency bands.

Theresistance of slurry pipelinetransportation has greatly impact on slurry transportation system. In order toimprove transportation efficiency,energy utilization rate,taking theappropriate drag reduction technology has a very important significance.Thispaper presents drag reduction technologies for slurry transportationapplications,including micro-bubble drag reduction technology and vibrationdrag reduction technology.

It is very important to recycle and deal with them effectively for environment protection resources saving. In this paper, on the basis of relevant knowledge of classified recycling, we combine the situation of our surveying actually, establish electronic information platform which is suitable waste electronics. More important being, we design a recovery bins can be classified recycling battery. What’s more, according to the waste electronics recycling system, we put forward to increase the recovery rate and the better classified recycling.

In view of the fact that the complex control of car moving device, its small application range, the difficulty to reach the accurate location of vehicles and so on, therefor a new design and research for a car moving device of remote control is proposed; The Mecanum wheel is chosen to achieve the omnidirectional movement, so that the vehicle can reach the predetermined position quickly. The electro-hydraulic push rod is used to realize the automatic lifting ,and it is also convenient and efficient; In addition, AT89C52 microcontroller which cost less but can meet the requirements realize the control.

This dual-ducted SUAV is a nonlinear and strong coupling of multiple-input and multiple-output system, and particularly between the pitch and roll channels channel coupling is strong, in order to implement effective control, it must be decoupled. The traditional methods are difficult to achieve effective control of the strong coupling of multivariable systems. Neural network which has a strong learning ability, is able to learn from the sample and can adapt to changing learning condition. Thus, the neural network can be used to simulate the learning process of operator, and operating characteristics information of objects can be excavated from the measured data, and accordingly change the parameters of the controller and decoupling network. This paper presents a attitude control algorithm of the dual-ducted SUAV which combine ADRC algorithms with neural network decoupling control algorithm, to design a SUAV decoupling controller. The simulation results showed that the attitude control channels between the pitch and roll were independently of each other, indicating a good solution to decouple the coupling between the pitch and roll channels based on neural network algorithm.

This dual-ducted SUAV is a nonlinear and strong coupling of multiple-input and multiple-output system, and particularly between the pitch and roll channels channel coupling is strong, in order to implement effective control, it must be decoupled. The traditional methods are difficult to achieve effective control of the strong coupling of multivariable systems. For the SUAV model of nonlinear coupling characteristics, based on the establishment of the UAV attitude model, this paper designed an attitude ADRC decoupling controller. The simulation showed this ADRC decoupling controller had strong robustness and immunity, and solved the channels coupling between the pitch and roll.

Based on the sub-mini dual ducted UAV dynamics analysis of Newton, and according to the characteristics of the hovering and variable posture mechanism, this paper combined methods of mechanism analysis with system identification to get the attitude model of under actuated sub-mini dual ducted UAV, which contained input variable, output variable and some unknown parameters. Then the subspace method used the real flying data to identify above the attitude model. Finally，the correctness of the identification model was verified.

Recently, the UAV has become the research focus at home and abroad. this paper puts forward a unconventional type: double ducted tilting Subminiature UAV system (SUAV) , and carries out the research of the control system for this SUAV. Since SUAV flight attitude control process has strong time-varying characteristics, and there are random disturbances, the conventional control methods with unchanged parameters are often unworkable. An on-line adaptive ADRC control system is designed in this paper. An on-line adaptive ADRC system implements a simultaneous on-line tuning of ADRC rules and output scale of ADRC control system. The flight experiment showed that the proposed adaptive ADRC system provides quicker response, smaller overshoot, higher precision, robustness and adaptive ability. It satisfies the needs of autonomous flight.

Since Small Unmanned Helicopter flight attitude control process has strong time-varying characteristics, and there are random disturbances, the conventional control methods with unchanged parameters are often unworkable. An on-line adaptive ADRC control system is designed in this paper. An on-line adaptive ADRC system implements a simultaneous on-line tuning of ADRC rules and output scale of ADRC control system. The flight experiment showed that the proposed adaptive ADRC system provides quicker response, smaller overshoot, higher precision, robustness and adaptive ability. It satisfies the needs of autonomous flight.

In an attempt to investigate the formation rule and corrosion resistance of the plasma electrolytic oxidation (PEO) coating on crevice surface of AZ31 magnesium alloy, the crevice coatings were fabricated on the samples of irregular shapes with different values of crevice width. The value of crevice width was varied from 200 to 350 μm for investigating the effect of crevice width on the surface and cross-sectional morphology, phase composition, corrosion resistance of crevice coatings. The results indicated that the crevice coating differs markedly in morphology and corrosion resistance when the value of crevice width reaches 350 μm, in spite of all coated samples have similar phase compositions. The effect of current density and ultrasound treatment on crevice coatings thickness were also studied systematically. Studies have shown that the increase of current density and the introduction of ultrasound treatment are both favorable for the crevice coatings.

Chaos is extremely sensitive to initial conditions, which makes the system with even smaller initial amount of changes can eventually evolve into a very different result. In an indirect field-oriented control of induction motor drive when estimated errors exist, within a certain range of parameters the system may evolve into chaotic motion through period-doubling bifurcation. In this paper an adaptive controller for synchronizing two indirect field-oriented induction motor drives under chaotic state is presented. Simulation results show that with the state-error feedback controller, synchronous state may be achieved rapidly and robustly.

In order to solve the impact of environment on reasonable production capacity of large mine, analyzed the main factors of environmental pollution affecting the coal mines, illustrated the coordination and interaction of various subsystems of the industry ecosystem in chart and used the environmental quality assessment to determine the mine environment grading and partition, determine the reasonable capacity of the large mines within the bearing capacity of the environment, present environmental protection measures in different areas.

Defects in the specimen of missile engine shell was detected by thermal wave image technology in this paper. In order to gain intuitionistic and accurate space structure image of the detected object, subtracting background and high-frequency emphasized filtering method were used to enhance the image quality. Then the defect was segmented from the background using particle swarm fuzzy clustering algorithm, while the defect size and depth were identified quantitatively. On this basis, 3D reconstruction of the defect by thermal wave image was recognized by Volume Rendering method. The results show that the precision of the defect quantitative identification is higher, and 3D reconstruction result is well, which help us to observe the location and size of defects intuitionisticly.

A comprehensive investigation was performed for repairing the different types of cracks appearing on the surface or inside the concrete lining at various depths. The material properties used in grouting and two methods for crack repair were discussed in details, and consequently reliable repair measures were proposed and implemented. It is a better choice to adopt the hole-drilling method for the relatively regular crack. The grouting pressure should not be too high and it is generally between 0.4∼0.6 MPa. For the second time grouting, the pressure maybe increased to 0.8 MPa. Other method is the pasting nozzles method which is more suitable for irregular cracks such as cracks with intensive density and crossing cracks. Its grouting pressure is generally between 0.6∼1.0 MPa. The in-situ tests in Three Gorges Project demonstrate favorably the feasibility and applicability of the proposed methods for crack repair within the lining concrete.

This paper researches and designs an information interaction interface, which exchanges information between electrical home appliances and smart grid, thus accomplishes the function of data acquisition and appliance control. With regard to the designed logical functional structure of external and internal grid information interaction interface, procedure of information interaction, interaction scheme and communication protocol during interaction process is analysed in detail. The procedure of interactional service between electrical home appliances and smart grid is illustrated by describing coordinating operation of grid information interaction interface's functional modules, by which the goal of power demand response, energy management and power load control is achieved finally.