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Based on IR2103S half-bridge drive chip, high-power wide voltage DC motor drive circuit is successfully designed. This paper analyses high power wide voltage DC motor drive control principle, H-bridge drive principle, control characteristics of MOSFET and drive method, moreover, this paper also introduces operating characteristics of wide voltage IR2103S half-bridge drive chip and its control logic and operation modes, in addition, it provides interface method for connecting IR2103S chip and single-chip microcomputer, and measures to control high-power wide voltage DC motor by the single-chip microcomputer.

The genetic algorithm is a randomized search method for a class of reference biological evolution of the law evolved, with global implicit parallelism inherent and better optimization. This paper presents an adaptive genetic algorithm to optimize the use of BP neural network method, namely the structure of weights and thresholds to optimize BP neural network to achieve the recognition of banknotes oriented. Experimental results show that after using genetic algorithms to optimize BP neural network controller can accurately and quickly achieved recognition effect on banknote recognition accuracy compared to traditional BP neural network has been greatly improved, improved network adaptive capacity and generalization ability.

In order to provide evidence for the adjust of grinding rate, we have did the experimental study on the grinding rate with different grinding concentration of Dahongshan copper, the tests indicate that the best grinding concentration and grinding rate of Dahongshan copper is 70% and 100%.

In order to provide evidence for the adjust of grinding concentration, we have did the experimental study on the grinding concentration of Dahongshan copper, the tests indicate that the best grinding concentration of Dahongshan copper is 70%. Generally, the advantage range of fine grinding concentration is from 65% to 75%,so we choose the acceptable range of grinding concentration from 65% to 70% .

Ecohydraulics is an emerging interdisciplinary science and mainstream engineering researching on the interaction relationship between hydrodynamic characteristic and aquatic ecosystem, it integrates biology, geology, hydrology, morphology, ecology, engineering and other disciplines. Based on the collection of literature on ecohydraulics from Web of Science database, the bibliometric analysis on 563 literatures from the year 1991 to 2012 has been conducted, including publication year, author, country, institution, subject, source journal and keyword analysis. Some conclusions have been made that these literatures on ecohydraulics are growing exponentially year by year; these literature involves a lot of authors and forms three research groups which scattered in Britain, the United States and New Zealand, the result clearly shows a positive correlation between the number of published literatures and the length of the research history in this subject; the main institutions of these literature include United States Geological Survey, National Institute of Water and Atmospheric Research, Chinese Academy of Sciences, University of Lyon and University of Birmingham; and the subjects of these literature include environmental sciences & ecology, water resources, marine & freshwater biology, engineering and other subjects; more than 40% of the literature published in journals with the impact factors greater than 2.0. The main research contents are as follow: biological characteristics of aquatic organism, the impact of hydrodynamics on river habitats and aquatic organisms and, the feedback of the organism on flow. Theoretical analysis, system testing, statistical analysis and hybrid analog-digital simulation are primary research techniques and applications of the research concentrate on environmental flow requirement, habitat assessment, eco-engineering design and flow field control.

The viscosity of Pulp will affect the grinding rate directly, Elevated temperature, the slurry viscosity reduced. In order to study the effect on the grinding rate of temperature, we did the experiment by only changing the temperature, and three groups of contrast test was carried out. The results show that the grinding rate is improved obviously, when the grinding temperature increases from 16 °C to 42 °C.

The Copper-bearing minerals Powder (≤2mm) is used in conical ball grinding, the experimental study shows that the effect of the three kinds offactors on grinding efficiency is obvious. In this paper, we will start from the pulp rheological perspective to discuss why this is. In the end, the optimal conditions include the best pulp density 70%, the best mill speed 86.33r/min and the best time 4 min.

This system based on single chip PWM dimming technology, with LED lamp as light source, STC89C52 be used as the core of the host device. The PWM control technique be used to realize the energy saving of LED lamp, on-off, brightness and so on. The circuit structure is simple, low cost, easy to operate, can be widely applied in real life.

A preliminary study on the micro-structure of a special sericite-jade material has been carried out by using the XRD and SEM methods. By XRD analysis, the 2M1 type sericite is identified as the main mineral composition of the white-colored, yellow-colored and green-colored jade. Quartz, as the secondary mineral, is also common in the green-colored jade. However, the dominant mineral composition of the black-colored jade is chlorite. SEM analysis reveals both the micro-morphology of the jade-forming minerals and the micro-structure of the mineral aggregates are various, which have significant relationships with the Guangning jade quality. Minuscular mineral grains and compact micro-structure make jade materials exquisite. Conversely, large mineral grains and the loose micro-structure make jade materials more rougher.

The high frequency induction heating power supply has received increasing attention from researchers, multilevel converter is a high voltage large power application areas of research focus and core, it solves the problem of the multilevel inverter output voltage waveform adjustment, avoids the problem of two times reversing that the load voltage in the commutation during the dead period occurred. An effective way to improve efficiency is to keep the power device of low voltage stress and less switching loss. A passive lossless snubber circuit is designed for inhibiting the reverse recovery current of diode and improving the turn-on condition of powers switch. The operation process of snubber circuit is analyzed and the parameter design method is given. The results of simulation have verified the validity of design methods and the conclusions given by theoretically analyzing in this paper.

Relay logic control circuit also known as chain control mode as a kind of traditional electric drive control mode, with its low cost, easy to implement, easy to master, strong anti-interference ability, the requirement of environment temperature is not high, easy to repair and other features, that holds a very important position in the industry control domain. This paper gives the new method of using Kano map to designing a relay logic circuit. Firstly, according to the demands of the object, draws the control truth table, writes the logic expression function, carries on the simplification using the Kano map to the logical function, deals with “competition” and “risk”, then the circuit could be got. A practical example is added to explain the designing method and procedure. Hence, give a systematic designing theory of relay logic circuit.

Aimed at the work conditions and the failure of the grinding ball in ball grinding, High chromium cast iron with the characteristics of long service life, high abrasion resistance and good shock resistance must be chose in the ball grinding . The best mixture ratio of chemical compositions was pointed out, and the production technological process by using die cast is introduced.

Au supported titania composite photocatalyst was prepared by one-pot synthesis method where titanate nanotubes as supports and which was subsequently transformed into anatase TiO2 during the water vapor treatment. The composite was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and N2 isothermal adsorption-desorption. Au nanoparticles in the crystallite size of 10-15 nm were uniformly deposited onto the surface of titanate nanotubes or anatase TiO2 nanoparticles. Some nanotubes were kept even at 120 °C and the composite had specific surface areas ranged from 163 to 310 m2.g1 depending on the vapor temperature. The photocatalytic activity of the composite photocatalyst was evaluated in the degradation of dyes acid red G (ARG) and methylene blue (MB) under UV irradiation. Au supported TiO2 had good adsorption ability to dyes, and showed an enhanced photocatalytic efficiency compared to the pristine titanate nanotubes.

The highly dispersed TiO2 sols composed of anatase crystallites (ca.5 nm) were prepared by peptization of amorphous precipitates with trifluoroactic acid (TFA) during the synthesis. The size and crystallinity of the particles were tuned by the subsequent hydrothermal treatment. The prepared TiO2 nanocrystals were characterized by X-ray diffraction and transmission electron microscopy (TEM). The TEM results indicated that the growth of the crystallites could be inhibited by the increasing addition of TFA and the average sizes of TiO2 nanocrystals were all ultrafine. The degradation of phenol over the nanocrystals after calcination at 500 °C was investigated. The photocatalytic results showed that the sample with a high addition of TFA obtained a better photocatalytic property than that of the commercial TiO2

This paper presents the design of integrated control for four-wheel steering (4WS) vehicle. A vehicle nonlinear dynamics model is built based on a lateral dynamics simplified linear model. A more accurate sideslip and yaw rate controller is used for lateral dynamics model of 4WS vehicle. Then a vehicle model based on the individual channel and partial decoupling design paradigm is identified from the vehicle dynamics. The sideslip and yaw rate controller is based on a linear multivariable combined with lateral dynamics model and the front and rear steering angles. The results of a stability analysis and simulations are presented to show that the 4WS integrated control system can markedly enhance good vehicle lateral maneuverability.

The core/shell structured rutile/apatite was prepared by soaking rutile TiO2 (R-TiO2) microspheres into a simulated body fluid (SBF) only for 1 day. The as-prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX) and N2 adsorption measurements. XRD showed that the apatite content increased with prolonging the soaking time or increasing the SBF concentration. TEM and EDX demonstrated that apatite had been coated on the surface of R-TiO2 microspheres successfully. HRTEM indicated that the lattice spacings of 0.27 nm and 0.32 nm were assigned to (211) plane of apatite and (101) plane of R-TiO2, respectively.

Spindle-like bis (8-hydroxyquinoline) iron (FeQ3) complex has been synthesized with a facile method in a mixed solvent system at room temperature for 12 h. The molecular formula of the products is speculated by the C, H and N element analysis and thermal gravimetric analysis, and Fourier-transformation infrared spectroscopy was also utilized to measure its structure, which further confirm the molecular formula of the products. The observation of field emission scanning electron microscopy and transmission electron microscopy shows that the morphology of tris (8-hydroxyquinoline) iron complex is spindle-like structure. The photoluminescence of the products were also investigated. The results indicate that the photoluminescence emission of FeQ3spindles shows obvious blue shift contrasted with that of 8-hydroxyquinoline.

A simple method for preparing nanoscale copper ferrite particles with narrow distribution and uniform size was developed by auto-combusting the precursor using copper nitrate, iron nitrate, and malic acid as raw materials. The constituents and the thermal decomposition process of the precursor were studied by Fourier transform infrared (FT-IR), thermogravimetry-differental thermal analysis (TG-DTA) and X-ray diffraction (XRD). The results showed that the carboxyl and nitrate ion take part in the reaction during the auto-combustion process. The precursor decomposed completely at about 199 °C, to yield single phase product. Transmission electron microscopy (TEM) indicated that the average size of the as-burnt sample was about 90 nm.

Amphiphilic diblock copolymers based on methoxy polyethylene glycol (MePEG), 1, 6-hexanediol and maleic anhydride with different molar composition were synthesized by solution polycondensation. Self-assemble behavior of amphiphilic diblock copolymer in different solvents by dialyzing technique was discussed. The micelle morphologhy was observed by TEM. It was found that well core-shell MePEG1900/Polyester 2162 copolymer nanoparticles can be formed by self-assemble in acetone solution. In addition, the size of nanospheres measured using dynamic light scattering exhibited a narrow monodisphere size distribution and an average diameter in the ranger of less than 200nm.

Hierarchical bis(8-hydroxyquinoline) nickel(NiQ2) complex has been synthesized with a facile method in a mixed solvent system at 120 °C for 12 h. The molecular formula of the products is speculated by the C, H and N element analysis and thermal gravimetric analysis, and Fourier-transformation infrared spectroscopy was also utilized to measure its structure, which further confirm the molecular formula of the products. The observation of field emission scanning electron microscopy shows that the morphology of bis(8-hydroxyquinoline) nickel complex is flower-like structure. According to the result, it is found that the photoluminescence of bis(8-hydroxyquinoline) nickel complex is stronger than that of 8-hydroxyquinoline, which indicate that inorganic elements played key roles in their luminescence properties.

Yellow River-Crossing Project in South-to-North Water Transfer approach through the use of shield tunnel and its north bank departure shaft adopts diaphragm wall as enclosure structure. The depth of continuous wall of its shielding starting shaft is 76.6m, which is the deepest at present in china. The continuous diaphragm wall travels through the layer of silver sand, medium sand and loam from top to bottom, where the geological conditions are poor with large difficulty of construction. This paper sets forth construction of guide wall, reinforcing measures before construction, Trenching process, groove segment connections, innovative technologies of uplifting huge reinforcing cage and so on, which will provide guidance and lessons for the similar project

AZ91 magnesium alloy is selected as the matrix metal. SEM, EDS, Tafel and EIS were adopted and spot test was carried out to investigate the influence of pH value, phytic acid concentration, temperature,conversion time on corrosion resistance of conversion coatings. Result shows that process of phytic acid forming is the controlled metal corrosion process and the uneven surface pattern reflects the different chemical properties of two-phase current on magnesium alloy surface, which is implied by the conversion surface. It is proved by the test that pH value is committed the most to the corrosion resistance of the conversion coating, and the next is the phytic acid concentration. It is found that the corrosion resistance of the conversion coating is the best when pH value of the conversion solution is 4.5; The conversion coating has little influence on the cathode reaction dynamics, however, more importantly, it changes the dynamics of the alloy electrode anode solution reaction, therefore, the alloy’s anode current density decreases while the corrosion resistance of magnesium alloy is enhanced.

With soaking treatment, cerium and KH560 silane compound mixture conversion coating are formulated. Various means of analysis such as SEM, EDS, IR, Tafel and EIS were adopted to carry out analysis of surface pattern, element constitution and electrochemical corrosion for mixture conversion coatings of different immersion time. The result shows: When the mixture conversion coating of cerium and silane are formed, the cerium conversion coating takes the priority in generation. Silane conversion coating is mainly absorbed to the cracks of cerium coating, once some exposed base are found at the minor cracks of the silane coating, as a result, definitely cerium coating is generated to make up the exposed base. Therefore, the corrosion resistant capabilities of the mixture conversion coating are higher than pure cerium conversion coating and silane conversion coating.

Nano-sized as-synthesized MCM-41 (with template) particle, whose pore channels and outer surface are full of organic CTAB template, is used as compatibilizers for immiscible polypropylene (PP)/ethylene–propylene–diene terpolymer (EPDM) blends. The mechanical properties of PP/EPDM/mesoporous MCM-41 ternary composites are investigated. The nano-structured MCM-41 (without template) material constituted by an ordered network of hexagonal channels is selected to compare with as-synthesized MCM-41 (with template) in mechanical properties of PP/EPDM blend. The results shows that tensile strength of the blend is increased by 13.6% and the impact strength is increased by 71.6% by addition 2 wt% content of as-synthesized MCM-41 (with template) compared to pure PP/EPDM. The presence of MCM-41(without template) in the blend cannot improve the mechanical properties obviously. SEM reveals that the enhancement of the interface is obtained by adding MCM-41 (with template). SEM also indicates that incorporation of as-synthesized MCM-41 (with template) into PP/EPDM blend can act as compatibilizer, which results in a decreased particle size of dispersion phase together with morphological evidence of interfacial adhesion. However, with the presence of MCM-41 (without template), the interface do not show clearly change compared with the PP/EPDM blend. The PP/EPDM/MCM-41 (with template) composites show higher tensile strength and impact strength than the PP /EPDM / MCM-41 (without template).

The surface modification of corn starch and the use of modified starch as reinforcing filler partly replaced carbon black in rubber composites were studied. The surface of starch was modified with 3, 4-2H-dihydropyran and maleic anhydride by grafting reaction in organic solution, that is, the process of etherification and the esterification of the starch. The structure of the ether ester starch was investigated by FTIR, SEM. Based on the results of the mechanical and heat building up properties of composite, it is showed that using modified starch as reinforcement filler filled into the rubber partly replaced CB, the characteristics of high flex life and low heat building up for composite can be obtained.

With different means of soaking treatment, simple cerium conversion coating, KH560 silane conversion coating, cerium silane conversion coating and silane cerium conversion coating are formulated. SEM, EDS, Tafel and EIS measurements were adopted as the analysis approaches, and organic resin is coated on the conversion coating surface for the salt spray test, so as to check mainly how much the corrosion resistant capabilities could be improved if conversion coating is applied to the magnesium alloy. The result shows that the cerium silane conversion coating and silane cerium conversion coating have a higher self-corrosion potential, lower corrosion current density, improve the binding force between the organic coating and magnesium alloy matrix more effectively, thus enhance dramatically the corrosion resistant protection capabilities for the whole coating applied on the magnesium alloy matrix.

According to the structure dynamics and the aerodynamics theories, based on and equations turbulent model, the paper deduced metro train head aerodynamic models. On the basis of three new train heads designed by changing the profile or length of longitudinal projection, the outside flow fields around streamlined B-type metro vehicle were simulated with 3-D incompressible viscous fluid theory based on CFdesign software. This paper analyzed theoretically metro train’s physics characteristics in the tunnel, studied its pneumatic idiosyncrasies in running time, calculated its air resistance coefficient, and looked forward to better head sculpt to reduce aerodynamic resistance and filled the metro train heads with beauty and flavor of the times.

Amphiphilic diblock copolymer was synthesized in one-step or two-step process by using of methoxy polyethylene glycol (MePEG), 1,6-hexanediol and maleic anhydride and characterized by FTIR and GPC. IR spectrum of amphiphilic diblock copolymer confirmed that MePEG had grafted on polyester. Solution polycondensation, melt polycondensation, mode of adding monomers and reaction time were studied on effect of molecular weight and its distribution. The GPC results showed that fairly narrow molecular weight distribution was obtained in solution polycondensation by one-step process. In addition, self-assemble behavior of amphiphilic diblock copolymer was discussed in different solvents by nanoprecipitation technique. The micelle size and aggregation was measured by TEM. It was found that MePEG1900-b-Polyester2162 copolymer self-assembled in acetone solution against water into well core-shell nanoparticles.