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Al-Si coating in different hot dip process conditions were made by a hot-dip galvanizing simulator, and distribution regularities of chemical elements in coating were studied by means of GDS, SEM, EDS and XRD. The results show that the hot dip temperature has no obvious impact on elements distribution in coating, but has some impact on Si content in surface coating. The hot dip time has no obvious impact on surface coating element content, but has distinct impact on deep coating element content. With the hot dip time increasing, Al content decreases, Fe content increases, and Si content decreases. Al-Si coating is composed of 3 layers, surface layer contains fine and close Al2O3 film, which has good anti-oxidation property on high temperature and hot stamping property, middle layer contains high melting point phase ,such as rich Fe phase , FeAl3 ,which has excellent anti-oxidation property on high temperature. The elements in diffusion layer can even be transited to basic steel, so coating has good adhesion property.

Algogenic organic matter (AOM), including extracellular organic matters (EOM) and intracellular organic matters (IOM) can interfere with drinking water treatment processes and cause water quality problems, among which the formation of disinfection byproducts (DBPs), microcystins and odor and taste compounds are of particular concern. In this study, the formations of THMs, Microcystins-LR and 2-MIB during four growth phase (lag phase, exponential phase, stationary phase and death phase) were investigated. The THMs formation potential of EOM and IOM were compared. Higher CHCl3 concentration was found in IOM than that in EOM. In the presence of bromide, more brominated-THMs generated, and the TTHMs increased more rapidly in EOM than IOM. The 2-MIB was found a similar trend with the MC-LR in the four growth phase. The total 2-MIB was gradually increased as a function of the time. The formation of MC-LR and 2-MIB depended on algae density.

In order to effectively ascertain the failure mechanism of piled wharf affected by slope deformation in earthquake, numerical analysis is conducted by Finite Element Method in this paper. In the computational model, elastic plastic characteristic of subsoil, discontinuous behavior of pile soil interface, and nonlinearity of structure material are considered to conduct seismic computation in time domain. Numerical results show the possible locations of wharf structure which generate cracks and plastic hinges. Some conclusions are drawn and can be reference for engineering design and practical project.

The design for a plate of cold stamping die design, Analysis of the technology of first part, determine the mould structure scheme, design choose zero, components, mainly to the punch, concave die, die and punch, design, drawing mould assembly drawing.

In the current environment of energy saving, dumper run energy efficiently that has great practical significance. The drive motor speed determines the roll-over machine efficiency, with the result that motor speed optimal control using adaptive PID control system. Contrary to the volume of PID control, using neural network online-tuning; On hand of network selection, RBFNN and F-RBFNN are selected. Compared with the classical PID control, the PID control based on F-RBFNN and RBFNN achieve the amount of online tuning the parameters of PID control. Especially, compared with RBFNN, F-RBFNN which combines a fuzzy logic technology and RBFNN is more suitable for real-time nonlinear control of the roll drive motor speed. Because parameters tuning more rapidly and static and dynamic performance and anti-interference ability more powerfully.

Taking the wavelet decomposed approximate image as the main research object, a direction estimation method for moving object was proposed in this paper. Firstly, the approximate image for the frame of the video was obtained via wavelet decomposition; and furthermore, the motion estimation on the approximate image was achieved to obtain the motion vectors. Finally, the motion vectors were described as polar coordinate form to compute the number of motion vectors in specified angles and the information entropy of the motion directions. The experiment results show that the proposed method can remove the effect of noise and the results of direction estimation are consistent with the actual motion directions.

In order to study the effect and influencing factors of bromate removal by ultraviolet treatment in drinking water, by carrying out laboratory test in simulated water and raw water samples, the action of UVC and UVA on bromate were investigated. The results indicated that bromate transformes into bromine ion under UVC treatment, but there was a small amount of UVA in the UVC lamp emission spectrum. Separate experiments on UVA treatment of bromate indicated that UVA could be considered as an interference factor for UVC treatment of bromate, and it should be restricted in the UVC lamp emission. The conversion of bromate to bromide was inhibited by suspended matter, which led to a rise of water turbidity and had influence on the reduction of bromate by UVC. When the water pH was 5.5~9 the same UV dose, the reduction of the bromate concentration by UVC treatment did not change significantly.

Carbon nanotubes (CNTs) have aroused widespread attention due to their high potential sorption capability for chemical pollutants. This review summarizes the adsorption mechanisms of organic chemicals and metallic ions with CNTs in aquatic environment and the factors affecting the adsorption. For a better understanding of the mechanism, future research works on combining the chemical experience and molecular dynamics (MD) is recommended.

In this experiment, preparation of samples were based on original ratio of bauxite matrix Al2O3-SiC-C castable for iron runner, and partial bauxites of size 8-5 mm, 5-3 mm, 3-0 mm and 2O3-MgO-C materials from spent ladle bricks, respectively. Si3N4 and B4C were introduced as appropriate additives. Effects of their amount on the performance of Al2O3-SiC-C castable for iron runner were investigated by testing on physical properties and erosion resistance of the samples after sintering. The results showed that the introduction of Si3N4 and B4C led to high temperature flexural strength of the recycled castable samples decline, while the right amount could improve the room temperature flexural and pressure strength along with the erosion resistance to blast furnace slag. When introduced 3% of Si3N4and 0.3% of B4C respectively, the comprehensive performance of the samples were the best.

A torsional vibration mechanical model of the transmission system of a certain cetarpillar vehicle is established using mass distribution method. The torsional vibration model, containing multi-stage simple and compound planetary gear transmissions, fixed-axis transmission and power split/converge system, is established based on Lagrange Equation. Matlab is used for presenting and writing the according program of the modal analysis of free torsional vibration. The study is focused on the torsional vibration characteristic of the system on one specific working condition and the similarity in the inherent characteristics of the system on different working conditions.

In this experiment, preparation of samples were based on original ratio of bauxite matrix Al2O3-SiC-C castable for iron tap channel, and partial bauxites of size 8-5 mm, 5-3 mm, 3-1 mm and 2O3-MgO-C ladle bricks, respectively. Effects of recycling ladle lining materials on phase composition and microstructure of Al2O3-SiC-C castable for iron runner were investigated by XRD, SEM and EDS. The results showed that new phases SiO2 and (Mg0.804Ca0.196)3Al2(SiO4)3 were formed in the castable at 1450 oC in air atmosphere, and the spherical (Mg0.804Ca0.196)3Al2(SiO4)3 was formed on external surface of recycling Al2O3-MgO-C particle. thereinto, SiC oxidation to formed SiO2 with flow pattern character was key element of the phase (Mg0.804Ca0.196)3Al2(SiO4)3 formation. The more fine and uniform of recycling Al2O3-MgO-C particles, the more spherical (Mg0.804Ca0.196)3Al2(SiO4)3 was formed in recycling Al2O3-SiC-C castable. Internal structure of theirs samples exhibited looser state with content increasing of recycling ladle lining materials.

In this experiment, preparation of samples were based on original ratio of bauxite matrix Al2O3-SiC-C castable for iron runner, and partial bauxites of size 8-5 mm, 5-3 mm, 3-1 mm and 2O3-MgO-C materials from spent ladle bricks, respectively. Effects of particle size and content of the recycled materials on sintering performance of the castable were investigated. The sintering performance was analyzed by measuring apparent porosity, room temperature flexural strength, room temperature pressure strength and high temperature flexural strength. The results showed that the apparent porosity of the samples overall tended to increase with content of the recycling materials increasing, while room temperature flexural strength, room temperature pressure strength and high temperature flexural strength of the samples reduced gradually. 8-5mm and 5-3 mm particle of 5%-15% the recycling Al2O3-MgO-C materials was more suitable for the preservation of high temperature flexural strength and room temperature strength of the samples than 3-1 mm and < 0.074 mm particle.

In ultrasonic flow metering, the inner pipe wall will be distorted by transducer’s installation, and the velocity profile of the meter will be different from that in a long straight pipe located in front of or behind the meter section. Changes in profile will finally influence the flow measurement accuracy. This paper shows a multi-path ultrasonic flow meter with its transducers installed at different positions. Our purpose is to find the best transducer installation position and to study the influence of path numbers and pipe diameters on the flow measurement accuracy at the best installation position. With a computational fluid dynamics (CFD) analysis, velocity profiles are calculated. Negative bias errors are obtained at all the three of the common installation positions. Similar phenomenon has also been observed in a real field experiment. The reasons for the negative bias error have also been analyzed.

Poly (3, 4-ethylenedioxythiophene) (PEDT) has attracted a great deal of interest during the last decades. PEDOT was popular with many applications such as antistatic coating, the hole injection layer in OLED. The thermal stability of PEDOT is important in these applications. In this study, PEDOT films were prepared by oxidative polymerization on the substrate polyimide (PI) films. Matrix polymer poly (vinyl prrrolidone) (PVP), Monomer 3, 4-ethylenedioxythiophene), retardant were dissolved in solvent as monomer solution; The Iron (III) p-toluenesulfonate hexahydrate (FTS) was used as oxidant solution. To investigate the heating properties of PEDOT films, the content of PVP, oxidant FTS, retardant were varied. The influence of treatment current density was also studied. Thickness of the PEDOT film was measured by Alpha-step surface profiler and the surface resistivity was measured by multimeter.

Silver carp were stocked in a pre-sedimentation pond in front of conventional water treatment processes in order to control Microcystis blooms in raw water. Silver carp effectively reduced the Microcystis flos-aquae concentrations, but green algae concentrations increased due to the ineffective filtration of silver carp for them. Water quality variations based on the effect of silver carp stocking on the two major phytoplankton communities (Microcystis and green algae) were evaluated by to investigate the relationship between water quality and phytoplankton cell concentrations in influent and effluent during Microcystis blooms period. Linear regression analysis indicated that the dominant species Microcystis governed the variation of turbidity and CODMn, and its concentration showed positive correlations with the two parameters. Meanwhile, the increase of green algae biomass led to the increase of pH and Chlorophyll a content, and showed obvious positive correlations with the two parameters in effluent.

The water solubility enhancement of 2,4´-DDT and 4,4´-DDT by humic acid and extracellular organic matter released from Microcystis aeruginosa was investigated by a ingenious sampling method and increasing apparent solute solubilities. Water solubility enhancements of the two DDT isomerizes by both humic acid and extracellular organic matter at the solution pH 7-11, and their solubilities increased with the increase of pH. Absorption coefficients Ciw (2,4´-DDT and 4,4´-DDT) increased with the increase of pH for HA and EOM, but Ciw for EOM are about two times than for HA at same TOC concentrations. The results suggested that more attentions should be paid to the enhancement of organic chemicals by EOM, especially in eutrophic water body where an increasing algae population usually appears, and the enhancement of DDT solubility by EOM may increase the risk of pesticide residues to organisms.

The drying of sludge can reduce its mass and the volume and consequently the cost of storage, handling and transport. In this paper, a one-dimensional model is established for the sludge drying process and hot water from the solar energy is applied as a discontinuous heat source (periodic heating). Based on the simplified physical model, the thermal behavior of the sludge drying process is investigated by numerical method. The effects of the sludge depth, mixing time and heat transfer coefficient are analyzed. The simulation results show that the most important effecting factor is the mixing time. One hour mixing cycle can increase heat transfer rate to 430%, 130% than that of without mixing and two hours mixing cycle, respectively. On the other side, both the sludge thickness and the heat transfer coefficient have some effects. For the cases studied the 40cm thick sludge with 1 hour mixing time is an optimal option.

The AR-Tri-training algorithm is proposed for applying to the abnormal voice detection, and voice detection software is designed by mixed programming used Matlab and VC in this paper. Firstly, training samples are collected and the features of each sample are extracted including centroid, spectral entropy, wavelet and MFCC. Secondly, the assistant learning strategy is proposed, AR-Tri-training algorithm is designed by combining the rich information strategy. Finally, Classifiers are trained by using AR-Tri-training algorithm, and the integrated classifier is applied to voice detection. As can be drawn from the experimental results, AR-Tri-training not only removes mislabeled examples in training process, but also takes full advantage of the unlabeled examples and wrong-learning examples on validation set

Green medical environment calls for fine quality of environment both in outside and inside. The article explains the function of natural ecological green plants in the improvement of medical environment quality from different angles, sums up the principles of green space design in various districts，and points out to lay stress on the characteristic of environment and to create green hospital which combine with the nature will be the direction of healthcare buildings design in the 21st century.

The failure of magnet wires used in inter-turn insulation of inverter-fed motor winding is the main cause which leads to the motor insulation breakdown. This paper conducted electrical tree breakdown experiments on magnet wire insulating film (FCR 100) used in the inter-turn insulation of JD117 inverter-fed motor and meanwhile combining with energy spectrum analysis and scanning electrical microscope (SEM), by which type and content of elements, breakdown main body and electrical tree channel could be clearly observed, the corresponding failure mechanisms were analyzed. The experiment results reveal that all the breakdown main bodies are located at the pointedness and insulation joint of magnet wires, of which dielectric strength is relatively lower; they are the insulation “weak point”, which should be paid enough attention and strengthened at the manufacturing period. The electrical tree breakdown time is quite long and the life span of magnet wire is 11 hours. The electrical breakdown strength of envelope is very low when containing metal impurity. It is also found that the aluminum occupies the highest content tested by energy spectrum analysis.

To reduce the production cost of polyhydroxyalkanoates (PHA) and disposal amount of excess sludge simultaneously, volatile fatty acids (VFAs) from alkaline excess sludge fermentation was used as carbon sources to synthesize PHA by unenriched mixed cultures. Released phosphorus and residual ammonium in the fermentative VFAs was controlled by adding magnesium to form struvite precipitation. Four VFAs liquids obtained was used to test the influence of initial carbon load and carbon to nitrogen ratio (C:N ratio) on the VFAs uptake rate, PHA storage rate and biomass growth rate. Results show that higher initial carbon substrate load results in relatively higher VFAs uptake rate and higher PHA storage rate, while higher initial C:N ratio results in relatively lower biomass growth rate from VFAs. VFAs generated from thermophilic alkaline sludge fermentation were a suitable carbon source for PHA production by mixed cultures.

Nano-sized titanium dioxide in aquatic environment poses potential impact on environment and human health. In this research, the impact of pH value, humic acid (HA) and divalent cations (Ca2+) on the stability of titanium dioxide nanoparticles(NPs) in the aqueous enviorment was investigated using a batch test. The results showed that the particle size of TiO2 NPs was not sensitive to the pH value but presented inversely proportional to zeta potential. The TiO2 NPs become more stable along with surface zeta potential, accompany with small particle size and high dispersion. In the presence of HA, the particle size was smaller and TiO2 NPs could be stabilized. This might be synergistic effect of the ligand exchange and electrostatic force. Meanwhile, NPs particle size increased with the addition of Ca2+ and the stability of TiO2 NPs became decreased.

In order to settle the influence of measuring results of particles with its shape-variety, the scattering pulse width and peak distribution and the relation of particles’ size and shape characters are systems analyzed based on the Mie theory and perturbation ameliorating method. In addition, a theorem of equivalence probability area is setup and a method of obtaining the probability distribution function of shape particles in real time is built. At last, the theories are validated in the experiments. The effect of the particles’ shape is modified and the accuracy of measurement of the particles’ size is improved effectively.

Buton rock asphalt (BRA) is possessed of both performance and economic advantages. In order to reveal the modification mechanism, X-ray diffraction experiment (XRD), X-ray fluorescence spectrum analysis and environmental scanning electron microscopy experiment (ESEM) are used to study on microstructure of BRA in this paper. It demonstrates that BRA can extremely adsorb free bitumen due to abundant microscopic pores, which consists of 70~80 percent Buton rock (BR) minerals and 20~30 percent pure rock asphalt (RA). RA with high viscosity is strongly adsorbed internal and outer of the surface of BR, which has high alkaline pH, high crystallization and strong surface activity. Then a special microstructure named “RA~BR” blend with stable property and strong spalling-resistance capability develops. Meanwhile, dynamic stability rheology test (DSR) is employed to study on the rheological mechanics property of BRA modified asphalt mastic. The high temperature performance grade (PG) level of BRA modified asphalt mastic with different mixing content is determined. The reasonable mixing content of BRA in matrix asphalt is 20~30 percent. The research proves that BRA modified asphalt possesses wonderful high temperature stability and has broad prospects for pavement application.

It is well-known that soils may display strong nonlinear and inelastic characteristics. Furthermore, the viscosity or rheology of soft clays cannot be usually overlooked in the design of major structures founded on soft ground. Especially, rheologic deformation of soils may get considerable under high stress level. In fact, the saturated soft ground usually displays low strength, sensitive thixotropy, and high compressibility. In this paper, the soil deformation on interaction behaviour of piled rafts and soil foundation by using a fully coupled finite-element method of consolidation in which an elasto-viscoplastic model is incorporated. Through numerical computations, it is demonstrated that the coupled creep-consolidation analysis can give a more rational evaluation of overall performance of interaction of piled raft and soils and conventional analyses which overlooks time-dependency of soil deformation may give rise of inaccuracy in engineering evaluation and design of structures.

Degradation of acid dye wastewater has been studued by using resin D072 load Fe2+ as heterogeneous Fenton catalyst. The effects of the initial PH of solution,the H2O2 adding doses,the amount of catalyst and the reaction temperature on the degradation of acid dye wastewater have been investigated in detail. According to experimental results, the optimal pH was pH3, the H2O2 adding doses was 333mg/L, the amount of catalyst and the reaction temperature were 10g/L and 27°C, respectively.

As an important oxidants, Chlorine dioxide was more useful in the decolorization of Reactive Red KE-3B, Reactive Blue KN-R, Reactive Red X-3B and Reactive Blue X-BR. It was found that the optimal pH=8，the optimal initial dosage of ClO2 and reaction time were 60 mg*L-1 and 15 min, respectively. The optimal reaction temperature of dyes were 80°C. Chlorine dioxide seems to be viable method for achieving significant decolorization of dying industry wastewater.

Relative motion between grinding wheel and workpiece makes the lubricant film pressure formed by grinding fluid in the grinding area increase, consequently, dynamic pressure lubrication forms. The grinding fluid flow field mathematical model in smooth grinding area is established based on lubrication theory. The dynamic pressure of grinding fluid field, flow velocity and carrying capacity of lubricating film are calculated by the numerical analysis method. An analysis of effect of grinding fluid hydrodynamic on the total lifting force is performed, and the results are obtained.

Grinding is often to use the grinding fluid because of the high temperature in the grinding area. During the process of grinding, which is used traditional way of grinding fluid supply, gas barrier layer which around high-speed rotary wheel impeded effective grinding fluid into grinding zone, so it creates huge waste and pollution. Minimum quantity lubricant (MQL) grinding as a way of Green Manufacturing is proposed in recent years. So far, the problem of MQL can be applied in grinding has not been confirmed. In this paper, the applicability of MQL in grinding is studied by comparing the experiment of traditional grinding fluid supply method, minimum quantity lubricant grinding method and dry grinding method, and this study is based on theoretical analysis of minimum quantity lubricant grinding.

Chironomus kiiensis larvae which cannot be exterminated by conventional disinfection process propagates prolifically in eutrophic water body, and it therefore turns to be a potential problem encountered in drinking water quality. In this work, the quantitative experimental studies were carried out on removal of Chironomus kiiensis larvae in raw water by coagulation-sedimentation process. The coagulation jar test showed that the Chironomus kiiensis larvae could be partially removed from water by coagulation-sedimentation process. Based on it, removal effect of pre-oxidation combined with coagulation-sedimentation process on Chironomus kiiensis larvae was evaluated. The results showed that chlorine dioxide pre-oxidation possessed better removal performance than prechlorinion, and Chironomus kiiensis larvae in the raw water could be completely removed by chlorine dioxide pre-oxidation in combination with the coagulation-sedimentation process at chlorine dioxide dosage of 0.8mg/L. The pH in the range of 6-8 did not affect the inactivation efficiency of chlorine dioxide, whereas pH 10 resulted in around 10% decrease in removal rate. Meanwhile, the removal rate of Chironomus kiiensis larvae improved with the temperature increasing within the range investigated of 15-30°C. The removal rate was reduced by 6.7% when temperature reduced from 30°C to 15°C.

Resin D072 was more useful on the adsorption of Fe2+ as a heterogeneous catalyst in the presence of H2O2, which had high catalytic activity in the decolorization of reactive red KE-3B. The conditions of the adsorption of Fe2+ by D072 were optimized, including the initial pH, the Fe2+ concentration and reaction time. It was found that the optimal pH was pH3. The optimal initial concentration of Fe2+ and reaction time were 840 mg L-1 and 60 min, respectively. It illustrated that the adsorption behavior of Fe2+ by D072 obeyed Freundlich adsorption model. The decolorization reaction of reactive red KE-3B was still faster though the catalyst already used 10 times because Fe leaching from the catalyst was negligible. The heterogeneous catalyst seems to be viable method for achieving significant decolorization of dying industry wastewater.

Additive processes can be defined as layered manufacturing, based on the dispersed/accumulated principle, Layered manufacturing is directly transforming 3D CAD models to real objects, the reverse engineering of mechanism can be applied to layered manufacturing for production complex geometries for long-term consistency, and the analysis demonstrates the application of the reverse engineering fulfills the segments of design, production, inspection, test. The most notable advantage is the combination of digital technology and geometric model rebuilding technology.