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There is a currently desirable demand for high strength steels with good ductility reduce the weight of steel parts for automobile and train applications. Retained austenite in steels can improve the toughness and plasticity. The austenite reverse transformation + quenching and partitioning (ART + Q&P) process was treated on a 0.2C-Mn-Si-Cr low alloyed steel, a multiphase microstructure composed of intercritical ferrite (IF), martensite, bainite and retained austenite (RA) can be obtained in the low carbon steel. Microstructures of the steel treated by different heat treatments were characterized by SEM and XRD. Results show that the formation of RA in low alloy steel depends on the following: (1) the enrichment of the carbon and manganese in the reversed austenite during the ART step; (2) the secondary enrichment of carbon in retained austenite during the following Q&P step. High fraction of RA (14vol.%) was obtained through the two-step element enrichment treatment (ART + Q&P). Due to continuous TRIP effect of RA during the deformation, a good combination of strength and plasticity was achieved in our works: the product of strength and elongation is greater than 35 GPa•%, the tensile strength is more than 1230 MPa, the yield strength greater than 890 MPa, the total elongation is about 28.6%.

the process of the wheel style grinding wheel grind concave surface of rotors has been simulated in this paper,through changing of the location of grinding point, the qualitative change of the strain and stress has been simulated and analyzed, obtaining that when the grinding point is at the midpoint of wheel grinding arc, the strain and stress of grinding wheel are the smallest, when at other locations, strain presents parabolic and spreads to the edge, the maximum and minimum stress are in the process of gradually decreasing as grinding dot moving from the edge to the halfway point , and the maximum stress and strain are occurred in a neighborhood of the grinding point.

A new type of high strength and low cost bainitic steel with ultra-low carbon content and high Si content has been developed on the basis of Mn-series air-cooling bainitic steels. The tensile properties of YS>690MPa and the impact toughness of AKV>60J at-40°C were obtained by controlling the processing parameters. This was attributed to the formation of the grain boundary allotriomorphic ferrite (FGBA) and the granular bainite (GB) with different shape of M/A islands. The high strength due to the inter-lath lamellar M/A islands or retained austenite companying with high dislocated bainitic ferrite laths of average 300nm width. The effect of microstructure on the impact crack initiation and propagation was studied. The results showed that crack initiation occurred in two different types of sites: at interphase boundaries of bainite ferrite (BF) and M/A islands, at grain boundaries. The FGBA and bainite ferrite (BF) both had blunting effect on microcrack tip to reduce the crack propagation path. Because of the presence of FGBA, the unit crack path was short, at less than 5μm. The blunting effect of BF could be enhanced by the M/A islands, which force the cracks change the propagation path and reduce the unit crack path to less than the size of bainite packets. The mechanism of low temperature microcrack origin of the ultra-low carbon bainitic (ULCB) steel with the microstructure of the FGBA and GB was also discussed.

Considering the feature of roller capacity with dynamics change in round bar production, a hot-rolling batch planning problem is studied. Firstly, the problem is formulated as a different capacities vehicle routing problem (DCVRP). And then, a mathematic model is built with two optimization objectives, minimization for total set-up time and maximization for utilization of roller. Secondly, an algorithm based on constraint satisfaction technique is present with variable selection rules and value selection rules for billet selecting, grouping and sequencing, and constraint propagation for searching-space reducing and rolling-unit partitioning. Meanwhile, the current capacity of online roller is updated dynamically during the solving process of algorithm. Finally, comparing results indicated that the proposed model and algorithm are effective and efficient.

AlMgB14 is a novel hard and brittle material which need be improved toughness for utilizing as cutting tool materials. In present study, intermetallic compound Ni3Al were attempted to dope the synthesised AlMgB14 materials. The microstructure of the AlMgB14-Ni3Al composites was analysized by scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy (EDX) and an X-ray diffractometer (XRD). The density, hardness and fracture toughness of AlMgB14-Ni3Al composites were also measured. The results showed that the major phases in AlMgB14-Ni3Al composites were AlMgB14, MgAl2O4 , Ni3Al and NiAl as well as W2B5. With the increasing of the amount of Ni3Al, more transgranular fractured features can be found in the fractured surface, the density of the AlMgB14-Ni3Al composites was increased, the hardness and fracture toughness of the AlMgB14-Ni3Al composites were decreased.

In this study, an iron ore was investigated with high content of phosphorus and sulphur about 1.09% and 1.4%, respectively. The grade of Fe is about 30%, which is mainly composed of siderite, about 23.40% of iron is existed in the form of silicate, such as chlorite, canbyite, and a small amount of pyrite, magnetite. The phosphorous mainly occurred as apatite, which is close united with the phase of iron, and the sulphur mainly comes from pyrite. According to the mineralogy analysis of run-of-mine, acid leaching and reduction roasting with sodium carbonate is used for the high efficiently dephosphorization and desulfurization. Magnetic tube experiment after reduction roasting with sodium carbonate, an iron concentrate with 84.5%, Fe was produced with 69.7% relative recovery as a result of magnetic tube experiment carried out with 3A electric current.

Silicoaluminophosphate (SAPO) molecular sieves with CHA and AFI structures have been synthesized under hydrothermal conditions from similar reaction mixtures using 3-Aminopropyl-triethoxysilane as silicon source. The XRD analysis indicated that the phase selectivity could follow the sequence of SAPO-34→SAPO-34+ SAPO-5→SAPO-5 →amorphous phase with increasing the amount of the silicon source. The phase selectivity can be explained by the increasing alkalinity of the medium with the 3-Aminopropyltriethoxysilane concentration.

Based on the F2-4 project in Zhujiang New Town of Guangzhou, this paper studies the construction scheme, process principle, technology requirement, etc, of super high-rise core tube copestone and the composite floor of steel composite wide-flat beam of hollow steel tube in order to guarantee the advanced technology, reasonable economy, good quality and excellent performance of the construction scheme. This research could lay a good foundation for the construction of the similar projects in the future.

Based on the project of Kingkey Financial Centre in Guangzhou, this paper conducts in-depth research on the key installation technology of box-shaped CFST columns with super-large section. The technologies including installation, measurement and control, welding, etc, have a good reference and practical extending application value.

Based on the project on F2-4 plot of Pearl River New Town in Guangzhou City, manual plastering protective layer construction technology of exterior mesh for super cross-section CFST cylinder is fully studied in this paper, the proposed new technologies of outer tube mesh and dry mesh are qualified with fast construction, energy conservation and environmental protection, low cost for later maintenance and so on. The new technology has good prospects for development and can be promoted widely.

A kind of nonwoven containing ferulic acid is prepared by electrospinning method. It was observed that the diameter of the fiber was about 200 nm by SEM. The antibacterial activities againstEscherichiacoliandS. aureuswere also investigated. The result showed the nonwoven prepared was effective against Escherichia coli, andS. aureus. Furthermore, Fabric UV transmittance test and air permeability were taken. It was found that the nonwoven achieved good UV protection and air permeability.

Using Orange Peels as Raw Material, a Stacking Structured Carbon Material has been Synthesized through Carbonizing and Activating Process. an Orange Peel Carbon/sulfur (OPC/S) Composite as a Cathode for Rechargeable Lithium/sulfur (Li/S) Batteries is Designed by Loading Sulfur into the Orange Peel Carbon (OPC) via Simple Impregnation and Heat Treatments. the OPC/S Composite Exhibits a High Discharge Capacity of 1100 mAh g−1 at 0.1 C, which is 23% Higher than that of Pristine Sulfur. Moreover, OPC/S Shows much Better Rate Capability and Excellent Cyclability. this Enhanced Electrochemical Performance could Be Attributed to the Thin Sheets and Irregular Wrinkled Surface of the OPC, which Act as a Conductor to Provide a Highly Conductivity and Short Li+ Diffusion Distance, as well as Absorbs Polysulfides.

In this study, the inhomogeneous properties and microstructure at typical position of an Al-7.5Zn-1.6Mg-1.4Cu-0.11Zr alloy forging in T7452 condition have been investigated using OM, SEM, TEM and EBSD analysis, tensile properties testing, conductivity measurement and fracture toughness testing. The results indicate that wherein the properties near the surface layer and in the core of the alloy forging exhibit a difference of 10% or more. There are obvious differences in grain morphology, quench-introduced precipitation and recrystallization degree in the two positions. Due to the high quenching temperature, there appears a heavy quench-introduced precipitation phenomenon in the core more than surface layer of the alloy forging, which improves the electrical conductivity, but significantly reduces the strength of the final material. And there is a higher proportion of the recrystallization organization in the core of the alloy forging, seriously affecting its elongation and fracture toughness. Microstructure inhomogeneity of the alloy forging determines the uniformity of its properties.

5-10nmPt-Ag nanoparticles were synthesized by Water thermal reduction, pluronic F127 and tetraethyl Orthosilicate (TEOS) have been used to synthesized mesoporous SiO2template. Pt-Ag nanoparticles have been absorbed onto the surface of mesoporous SiO2. Finally, PtAg/mesoporous SiO2nanocomposites have been modified on the surface of glass carbon electrode to prepared electrochemcial sensor which used to detect 2,4,6-dinitrophenol. In order to optimize experimental conditions, the synergistic reaction, buffer solution has been studied. The result show, when the potential at-0.404V, 2,4,6-dinitrophenol could be determined with a detection limit of 0.163μmol/L and linearity between 0.49-1667μmol/L . This sensor has high sensitivity, good reproducibility and stability.

The silica gel surface was alkylated by silane coupling agent KH-570 under the microwave assisted and orthogonal experiment was adopted to optimize the silica gel surface silanized experimental conditions with synthetic yield as index. With quercetin as the template molecule, 4 - vinyl pyridine as the functional monomer, ethylene glycol dimethyl acrylate as the cross linking agent, azodiisobutyronitrile as initiator, under the microwave assisted in silane silicone surface quercetin molecularly imprinted polymer was successfully synthesized. Take selected quercetin as index, another orthogonal experiment was implemented to optimize the quercetin-selective MIPs synthesis experiment on silica gel surface. What is more, the adsorptive property of quercetin-selective MIPs which was grafted on silica gel surface has been inspected. We have extracted of quercetin in the ethyl acetate from raspberry with quercetin-selective MIPs grafted on silica gel surface. Synthetic time have been shortened more than a dozen times, the efficiency of preparation of MIPs have been greatly improved.

An innovative spray deposition technique has been applied to produce in situ TiB2/Zn-30Al-1Cu composites. The microstructures of the spray-deposited composite were studied using optical microscopy, scanning electron microscopy, and X-ray diffraction. Both theoretical and experimental results have shown that the TiB2particulates are formed in the microstructure. It was found that the TiB2particles were distributed in Zn-30Al-1Cu matrix uniformly, and the TiB2particles are about 2 μm in size. Moreover, the presence of the TiB2particles was led to increasing of α’ phase with less 2 μm size in the composites which have a tendency to decompose to α+η structure.

In order to improve the output power of laser pulse in the inertia confinement fusion experiment, an arbitrary waveform generator is fabricated to shape the laser pulse. The arbitrary waveform generator is based on the impedance tapered micro-strip line technology and GaAs Field Effect Transistor set which has a good ability of generating voltage-controlled current. With the impedance tapered micro-strip line technology, the arbitrary waveform generator generates shaping electrical pulse with duration less than 10 ns, 330 ps time-domain adjustment. We use the shaping electrical pulse to modulate semiconductor laser which has the characteristic of direct modulate, the experiment results show the shaped laser pulse is obtained based on the shaping electrical pulse.

For the forging with complex shape, the preform design is a difficult problem in the process and die design. It has an enormous influence on the quality of the forging. In this paper, combining with the FEM, the Ant Colony Algorithm was used for the preform optimization design. The general Ant Colony Algorithm was improved to fit for the multivariate continuous function optimization. The preform die shape was represented by B-spline and the coordinates of the control point of the B-spline were taken as the optimization design variables. The optimization program was developed. Finally, aimed to decrease the material cost of the forging, the preform optimization of a typical H-section forging was obtained using the self-developed program. The optimization results show that the improved Ant Colony Algorithm is suitable for the preform optimization design of forging.

According to the electronic structure characteristic of carbon nanotube (CNT) together with the corpuscular property and volatility of transport electron, the theoretical model of current-illumination characteristic of CNT was researched. The I-V characteristic of CNT was emulation calculated based on ATK modeling software. The electromagnetic scattering model and electromagnetic simulation of the CNT current-illumination absorptive character were researched on account of current-illumination characteristic of CNT discussed by classical electromagnetic theory. The simulation results indicate that, the electric current passed in CNT and the voltage at two sides of electrode have linear relation when 0-2v voltage is put on the Cu electrode of the two sides of CNT. When the voltage is above a certain number, the electric current reaches saturation. The Ti-Ti combination of electrode gets the maximum absorption power when it reaches the height of 300nm.

The Pd/C catalyst with high dispersion was prepared by the activated carbon loading palladium nanoparticles (Pd-NPs) obtained in the protection of Tween-60. The above-prepared Pd/C catalyst was characterized by X-ray diffraction (XRD), inductively coupled plasma-atomic emission spectrometry (ICP-AES), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), chemical adsorption instrument. The influences of the size, dispersion, crystal type and electronic state of the Pd/C catalyst on catalytic activity were investigated. The results of Suzuki coupling reaction over the above-prepared Pd/C demonstrated that the reaction yield of aryl bromide under the conditions of 60°C for 1 h and para-chloronitrobenzene under the conditions of 80°C for 12 h reach 99% and 73% respectively.

The analysis index of the portable metal analyzer for trace heavy metals in natural water based on anodic stripping voltammetry (ASV) were performed. Simultaneous determination and monovariated analysis of trace heavy metals were investigated both subsequently. The reasons of disturbance in analysis were also discussed. The addition of Ga (II) was testified that can eliminate the formation of the Cu-Zn intermetallic compound.

With the analyses of eight different heavy metal elements (As, Cd, Cr, Cu, Hg, Ni, Pb, Zn)’ contents and distributions in the topsoil of Kunming City, the results show that the average concentrations of these eight elements in the topsoil of Kunming City were much higher than the background concentrations in soil in China, and the pollution assessments with the Single factor index method and Nemerow Pollution Index method, the result shows that in Kunming City, the Xishan District and Wuhua District exist a certain degree of heavy metal pollution problem of soil, but the soil environment qualities of Panlong District and Guandu District are better than other districts; analyze the causation of heavy metal pollution of soil with the elements data and current situation of Kunming City, the heavy metal pollution sources mainly from industrial pollution and traffic pollution.

The Co2+ doped TiO2 film(Co-TiO2) was prepared by in-situ growing on the pure Ti plate substrate in the electrolyte solution of Na3PO4 containing CoSO4·7H2O by micro-arc oxidation (MAO) process. The effect of the amount of CoSO4·7H2O adding into the electrolyte solution on structure of Co-TiO2 and its activity of photo-catalytic hydrogen production had been studied. It was found that the characteristic peak(101) of anatase phase and the characteristic peak(002) of rutile phase appeared and the red shift of absorption edge occurred for Co-TiO2 films when adding CoSO4 into the electrolyte solution. It was shown from experimental results that the highest hydrogen production rate was 0.33 μmol/ h·cm2 over the above-prepared Co-TiO2 in CoSO4·7H2O content of 8.7 g/L.

For the shortcomings of large overshoot and poor anti-disturbance ability when using the traditional PID control, ADRC control algorithm that is a nonlinear state error feedback control algorithm has been proposed in the sophisticated control system of static reactive power generator. The simulation results show that the algorithm can make the system reactive power compensation more quickly and more effectively, therefore the control strategy is feasible.

We previously presented an energy method for predicting the bounds of fracture toughness of brittle films on a soft substrate from nanoindentation. The method is now further improved by minimizing elastic-plastic work from the measured energy during ring crack formation. Then, we applied this method to determine the limits of fracture toughness of alumina films with a thickness of 100 nm. It was found that fracture toughness of the films is in the range of 1.8-2.2 MPa.m0.5, which is consistent with those measured by the conventional method.

Shallow geothermal energy is a new renewable high-quality clean energy that has aroused great interest of man for its renewability, huge stock, cleanness and high availability. Encouraged by the favorable policies of the government, shallow geothermal energy exploitation in geologically suitable areas has become a great priority. In this paper, principal rock-soil physical parameters are derived from field thermal response test set in the context of Qing’an, Suihua City, and subsurface temperature field is modeled to further establish the heat exchange performance parameters with a view to providing reference for the planning and proper deployment of GSHP-based shallow geothermal energy exploitation in this area.

A reasonable and effective control strategy for HEV (Hybrid Electric Vehicle) with HESS (Hybrid Energy Storage System) can improve the system efficiency and battery service life. A dynamic programming-based global optimal control strategy which fully considered the efficiency of each component in HEV is presented. To compare with the nonlinear proportion factor dynamic coordination strategy, the fuel consumption is not increased. The cycle numbers of battery are further decreased which benefits its cycle life improvement. The regenerative energy callback ratio improves 3% under the shanghai drive cycle as an example. Since this optimization algorithm considers efficiency of each subsystem, the efficiency optimum under the selected driving cycle was realized. It can also provide a reference for the non-linear scaling factor allocation strategies to determine the scale factors.

In this paper, the water environmental carrying capacity (WECC) was quantitatively analyzed considering the comprehensive effect of economy, society, resources, environment, and technology in Jiaozhou, Shandong province. An evaluation index system was established and applied in the evaluation of WECC in Jiaozhou from 2007 to 2011 with analytic hierarchy process (AHP) and vector modulus method. The results indicated that the WECC index was at low level in the range of 0.061-0.080 with the decreasing trend firstly but then increasing trend gradually, which shows that the water resources shortage is becoming the key factor restricting the development of Jiaozhou. The results conform to the real condition of Jiaozhou and the research provides the scientific methods and suggestions for the coordinated development of social economy and water environment protection.

CdS quantum dots/ Boron and Nitrogen co-doped TiO2 photocatalyst emulsions were synthesized by a complexation-controlled hydrolysis method at room temperature. Boron compounds and Nitrogen compounds were added to TiO2 precursor solution, and CdS quantum dots were attached to TiO2 particles surfaces by using chemical reaction. The hybird composite photocatalysts were characterized by XRD, UV-Vis. Their photocatalytic properties were evaluated through the degradation of acid red 3R dye. The results indicate that when TiO2 emulsion add to Boron ions, Nitrogen ions, and CdS quantum dots, the photocatalytic performance of the emulsion is the best.

Based on the comprehensive treatment project of Dagu Drainage River, this paper proposes the reutilizationof river sludge in roadbed filling to realize their recycling and harmless treatment and presents the first domestic classification standard of sludge utilization in accordance with relative state road and environment standards. The author carried out indoor tests and field construction tests of material performance after mixing sludge with lime, powder of building debris and lime slag respectively. These tests showed that all performance indexes of the sludge mixings meet the requirement of road specification, the limits of relative state standards and test requirements for heavy metals content and Extraction toxicity (ET).

In this paper, TiC reinforced steel matrix surface composites were prepared by vacuum evaporative casting infiltration process and self-propagating high-temperature synthesis. The effect of original composition, binder types and original coating density on the hardness, wear resistance and microstructure of the coating were also studied. The results showed that the Ti and C content was 80% while added 3% PVA, by pressed at 200MPa pressure leading optimal coating quality. Meanwhile the average hardness was 62.5HRC and the wear rate was 22 % of high manganese steel.

After surrounding rock is disturbed by some damage form a loosen circle in surrounding rocks of a roadway, in order to solving the range of loosen circle, mechanical mechanism of loosen circle was discussed on the basis of damage mechanics and loosen circle radius calculation formula proposed. This work has some certain reference for roadway support design.

A SVM calibration model combined with new information processing method of support vector machine and infrared spectroscopy is established. For the problem of model parameters affecting the analysis results, the optimization of the model parameters is studied through the experiment. The mixed gas containing hydrocarbon is used as an example, spectra data preprocessing, spectra analysis band, spectrometer scanning interval, types of kernel function for SVM calibration model, penalty factorC, and other parameters that affect the measurement results are optimized. The experimental results show that the accuracy of the analysis results can be improved in the case of the SVM calibration model optimized and the model has a practical application value.

PbS quantum dots/ Boron and Nitrogen co-doped TiO2 photocatalyst emulsions were synthesized by a complexation-controlled hydrolysis method at room temperature. Boron compounds and Nitrogen compounds were added to TiO2 precursor solution, and PbS quantum dots were attached to TiO2 particles surfaces by using chemical reaction. The hybird composite photocatalysts were characterized by nanoparticle size analyzer. Their photocatalytic properties were evaluated through the degradation of acid red 3R dye. The results indicate that when TiO2 emulsion added to Boron ions, Nitrogen ions, and PbS quantum dots, the reflux time is 15 min, the photocatalytic performance of the emulsion is the best.

In this paper, the feasibility of employing Aspen Plus in the simulation of oil shale retorting would be discussed by modeling of a low temperature retorting process with fischer assay experimental condition. The samples of 4th layer of No.1 deposit and 11th layer of No.2 deposit of Huadian oil shale have been simulated, and draw a comparison between the simulation and determination results of oil content, moisture content, retorting gas yield, semi-coke yield and ultimate analysis. The tolerance between the simulation and determination results is within a reasonable range, which indicate that the process built and the physical method selected are correct and reasonable and would provide reference for building the process of oil shale comprehensive utilization system.

Many efforts have been focused on stability problems of geotechnical structures with the limit analysis method. A key advance of this present method is that the problem is described only in terms of nodes and discontinuities connecting those nodes rather than element or bodies. The alternative approximation procedure might involve discretization of a given body using a suitably large number of nodes laid out on a grid, with the failure mechanism comprising the most critical subset of potential discontinuities interconnecting these nodes. The method using Mohr-Coulomb failure criterion to formulate the objective function is developed and the safety factor is determined from optimization. In order to evaluate the applicability and validity of the proposed method numerical results of some examples are presented and compared with the solutions obtained using other well-known techniques. The comparisons show that the proposed method is an effective method and can be applied to evaluate the safety factor in the analyses of slope stability problems.

Based on the project of Foshan International Home Expo City, this paper studied the control measures of the synchronous lifting process control of large-span pre-stressed double-layer suspended cable roof, and summarized some key points, which could be used as the common reference for the similar projects.

As a key component of turbine, the surface of turbine blade is usually designed to distorted variable cross-section surface, and the shape is very complex. This paper combines NURBS modeling theory and NC machining method, and use NC machining trajectory generation and simulation analysis by means of UG software. The results show that the method is effective for blade processing, and have a guiding role to the industrial production.

Aiming at the problem of serious deformation and failure of the surrounding rock of the main roadways in diabase zone in west wing on-500m leve in Dongbaowei Coal Mine and roof caving occurring several times, the rupture characteristics of roadway roof rock was observed in this paper. And the observation result shows that the rupture of the roof rock of the roadways in diabase zone has obvious zoning characteristics, and the roadway roof rock is divided into three zones: fragmentation zone, fissure zone and intact rock zone. According to this, this paper introduced a new concept of controlling roadway roof subsidence and redesigned the support parameters of the roof of the roadway in diabase zone. The deformation monitoring of the testing roadway roof rock was carried out, and the monitoring result shows that the anchor supporting scheme which was based on the “three zones” of roadway roof could control the roof rock deformation better. This indicates that roadway anchor support design method which is based on the “three zones” of roadway roof is correct and feasible.

Wire+arc additive manufacture (WAAM) is a high build rate process for production of near-net shape components layer by layer. The performance and quality of the deposited metal are heavily affected by the properties of wires, which are the raw materials for WAAM. Therefore there may be higher requirements for the qualities and properties of wires for WAAM than for welding. External surface qualities, micro hardness, composition and microstructures of five ER4043 aluminium wires were investigated in the present research. The results indicate that the internal and external properties of the wires exert great influence on the performance of the WAAM parts.

Sludge Concentration (MLSS) is one of major parameters for operation of Anoxic/Aerobic-Membrane Bioreactors（A/O-MBR）and it influences the removal efficiency of pollutants and the rate of membrane fouling as well. This paper focuses on the effects of different MLSS on the treatment of domestic wastewater, the quantity and composition of extracellular polymeric substance (EPS), and the variation of the rate of membrane fouling. It also includes a preliminary analysis of the correlation between EPS and membrane fouling to provide reference for future studies of the mechanism of membrane fouling.