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The main issues that limit the large-scale application of TiO2 in photocatalysis is its low utilization of solar energy and high recombination rate of photogenerated charges. To overcome these limitations, a type II WO3·H2O/TiO2 heterojunction has been prepared via a one-step mild hydrothermal method that uses Na2WO4·2H2O and P25 as the starting materials and proceeds at 150°C without requiring any post-heat treatment for crystallization, special solvents or additives. The XRD and HRTEM results show that the prepared powders were composed of orthorhombic WO3·H2O and TiO2, and demonstrate the existence of the WO3·H2O/TiO2 heterojunctions. The photocatalytic activity of the as-prepared WO3·H2O/TiO2 heterojunction powders was investigated by using the degradation of phenol. The WO3·H2O/TiO2 heterojunction powders exhibited the best photocatalytic performance when the nominal W/Ti ratio was 6.57%, and showed better photocatalytic performance than commercial P25 and orthorhombic WO3·H2O.

Laser selective melting (SLM) is a manufacturing process that uses laser to melt metal powder layer by layer to form parts, which can realize the integrated manufacturing of complex parts. In this paper, SLM technology and topology optimization technology are combined to carry out the integrated design of the aviation aluminum alloy support . After optimization, the weight of the support is reduced by 24%, the maximum displacement is reduced by 82%, and the maximum stress is reduced by 65%. The process simulation analysis of the whole SLM forming process is carried out by using Simufact Additive software. On this basis, AlSi10Mg powder is selected for laser selective melting of the support, The forming of the whole structure meets the expectation, is in good agreement with the process simulation results, and there is no visible cracking failure.

Pulverized coal ash can be used as an additive to reduce corrosion on heating surface of biomass boiler. Biomass ash and pulverized coal ash were mixed and coated on the metal surface for experiment; the results showed that the corrosion rate of the metal decreases by adding pulverized coal ash. With the increase of additive content, the corrosion gradually reduces. The effect of different pulverized coal ash on corrosion is different, but as the proportion of pulverized coal ash increases, the effect tends to be close. When the molar content of (Si+Al)/(Na+K) is about 2 and the ratio of Si/Al is about 1, the pulverized coal ash additive works best.

In order to study the forming quality of AlSi10Mg powder for SLM process without supporting structure, as well as lay the foundation of subsequence structural design of Aluminum SLM technique, a series of typical coupons have been designed and printed. Based on comprehensive consideration of layout direction, overhang angle, hole size, etc., Xline 2000R with optimized process parameter has been used as SLM equipment for AlSi10Mg powder. Through the analysis of printed coupons, the beneficial conclusion is made which can be used to guide future design, especially for the structure with complex shape.

With people's increasing demands for the improvement of air quality and quality of life, the demand for new decorative materials with air purification function will be increasing. This study is based on a life cycle assessment (LCA)-based approach to develop a list of resources, energy consumption and pollutant emissions in the life cycle of typical visible light photocatalytic liquid products, to calculate the important environmental impact of visible light photocatalytic liquid products, and to analyze and identify the critical stages affecting environmental performance of product, to guide the selection of green buildings and the development of ecological building materials. The results show that, for the purpose of visible light photocatalytic liquid, the global warming potential is 40.97kgCO2 equivalent/t, the abiotic depletion potential is 9.34×10-5kgSb equivalent/t, the respiratory inorganic index is 7.88×10-2kgPM2.5 equivalent/t, and the eutrophication is 4.13×10-2kgPO43-equivalent/t, acidification effect is 0.34kgSO2 equivalent/t; and the environmental impact in the product life cycle for the purpose of this study are mainly resulted from energy use, and transport process represents the main stage of eutrophication.

In this study, Cu/TiB2composite coating was in-situ prepared on 304 steel by laser cladding. This coating applies to hospitals, schools and some public places where cross infections happen more easily because of its good antimicrobial properties and abrasion resistance. Before laser cladding, pre-blend of Cu powder, Ti powder and B powder were undertaken by ball-milling in two different proportions (10% wt (Ti+B) and 20% wt (Ti+B)). And the atomic ratio of Ti and B was 1:2. After a series of experiments, the best parameters were achieved. They were laser power (950W), scanning speed (14mm/s) and spot diameter (3.8mm). Samples after laser cladding were characterized using optical microscopy, scanning electron microscopy and X-ray diffraction. The results showed that TiB2was fabricated in-situ. The dispersion degree of Cu was higher in the coating of 20% wt (Ti+B). The hardness of the 10% wt (Ti+B) coating was HRC57±4. With the increase of percentage of wt (Ti+B), the hardness of 20% wt (Ti+B) coating was HRC74±5. Both of them performed better than pure copper. Relative to pure copper, the abrasion resistance of Cu/TiB2composite coatings was more excellent. The results of antimicrobial experiments showed that, with the increase of percentage of wt (Ti+B), the antimicrobial properties were decreasing. But they still could to be considered favorable.

The MgAl2O4 spinel ceramic specimens with five different alumina contents ( w(Al2O3)=66%,72%,78%,85%,90%) were prepared using alumina micropowder and magnesia micropowder as raw materials, after mixing, shaping, drying, and heating at 1800 °C. The crucible specimens were tested for slag corrosion with commercial gasifier slag at 1500 °C for 2 h under oxidazing and reducing atmosphere. The specimens before and after slag test were studied by analyzing the microstructure and element distributions of corroded specimens with XRD, SEM and EDS. The results show that the slow dissolution of spinel into slag was observed because a low melting point material was formed by spinel reacting with CaO and SiO2 in slag on the surface of the spinel block. Meanwhile, FeOx in the slag was absorbed around the surface of spinel block to form the multiple solid solution, which was composed of MgO-Al2O3-FeOx and had a denser microstructure. The absorption of FeOx in slag had contributed to the resistance to slag penetration for the spinel. The relationship between the absorption capacity of spinel on FeOx and the chemical composition of spinel was discussed.

A self-assembled ZnO tail-like cluster (TC) had been successfully synthesized by a simple chemical vapor deposition method. Scanning electron microscopy observations show that ZnO TC is composed of bushy ZnO microwires with flower-shaped cross sections. Long and narrow furrows can be clearly observed on the surface of the ZnO TC. A possible growth model is proposed to discuss the formation mechanism. The analytical result indicates that the flower-shaped ZnO microwires are formed by the lateral coalescence of ZnO wires at high temperature. The room temperature PL spectrum shows a prominent UV emission band around 380 nm, and no green emission is found, implying that the unique flower-shaped ZnO microwires have high optical quality. This controlled growth of ZnO TC may have implication for potential applications in novel optoelectronic micro/nanodevices in the near future.

Stable TiO2aqueous dispersion with an averaged secondary particle size of about 10 nm was achieved by using commercially available dispersant Di-7N. The stability of the dispersion was measured by Zeta-potential test. And the results showed that the optimal mass fraction of Di-7N was 12 wt%. The adsorption mechanism examined by FTIR analysis indicates that the carboxylate groups in Di-7N is absorbed on the surface of nano-TiO2particles and the adsorbed structure is proposed to be bidentate chelating.

The modeling and optimization of machine tool’s dynamic performance remains to be a grand challenge in machine tool design. In this paper. In order to identifying the concentrated modals of a horizontal machining center, a combined experiment modal analysis method is proposed. A FEA dynamic model accurate in frequency and mode shape is built and verified by comparing with EMA results. Based on the model the optimization of frame structure is made, Simulation results shows the optimized frame enhances the dynamic performance of machine tool.

The desulphurization process parameters of vanadium bearing hot metal were optimized. It is found that it has the best desulfurization effect in 100t hot metal ladle, when the lance position is 280mm, the ratio of lime to Mg is 3:1, and the Mg injection rate is 9kg/min. The Si and Ti content of hot metal can increase the activity of S. With the increase of Si and Ti content of hot metal, the final sulfur content has a reduction trend. When the content of Si and Ti is lower than 0.35%, the final sulfur content of hot metal increases, and the hit rate decreases. The effect of hot metal temperature on desulfurization end point hit rate is obvious. When the hot metal temperature is between 1300~1320°C, the hit rate of desulfurization end point is higher. When the temperature is below 1300°C or above 1320°C, the sulfur content increases. After optimization of process parameters, the Mg and lime consumption per ton of hot iron are reduced by 0.11kg and 0.54kg, respectively, with the average hit rate of desulfurization end point increased by 22.6% and 10.7%, respectively.

Using elastic mechanics and fracture mechanics, analyzing the coal seam hydraulic fracturing breakdown pressure, given its theoretical formula. According to hydraulic fracturing stress status, given the form of two typical hydraulic fracture morphology. Analyzing hydraulic fracturing highly elliptical shape. The displacement field in plane stress state is given, and the theoretical formula of fracturing radius of hydraulic fracturing is deduced. The fracturing technology of underground fracturing is presented, and the fracturing location and fracturing parameters are determined. In Sihe Coal Mine conducted fracturing test, the test results showed that: the average of drainage volume of fracturing hole improved 4.4 times compared with non-pressed-hole. The extraction compliance time is reduced by 38%. Roadway tunneling speed was improved by 15%. It can solve the problem of gas overrun in roadway excavation well, and has a good application and popularization value.

To prepare a late-model and functional wood-plastic composite (WPC), the reversible thermochromism crystal violet lactone microcapsule was prepared by situ polymerization, then fabricated reversible thermochromism WPC by microcapsule and low density polyethylene with Maleic anhydride grafted polyethylene. Comparing the L, a and b data of apparent color of reversible thermochromism WPC, the value of chromatism (ΔE) showed the difference of heating before and after, it was also measured to characterize the color-change level; the mechanical properties of ordinary WPC and reversible thermochromism WPC were measured respectively to compare the advantages and disadvantages of two kinds of WPC; Then the storage modulus and loss modulus of ordinary WPC and reversible thermochromism WPC were determined to distinguish the good from the bad of two kinds of composites. The results indicated that the reversible thermochromism WPC is a functional composite with noticeable color-changed effects, and tensile strength, bending strength and interface compatibility were better than ordinary WPC, but had worse impact property contrarily.

The microstructural evolution in annealed Mg-3Al-1Zn (AZ31) magnesium alloy during high density electric current pulses (ECP) treatment is investigated by using a same current density with different processing numbers. It is found when the processing number of the ECP treatment is not greater than four times, the grains are refined and more homogenized, and the texture intensity obtained from the (0002) pole figure appears an obvious enhancement from 11.22 to 22.88. However, increasing the repeated ECP processing number will cause the coarsening of grain size and the decreasing of the texture intensity. The mechanism of the microstructural evolution during ECP treatment is discussed from the point of view of grain boundary motion.

In order to improve the distribution of second phase and performance the Cu-Cr-Zr alloy was processed by solidification under the effect of electromagnetic stirring (EMS) and in situ drawing deformation. Study of Cu-Cr-Zr conductivity and mechanical properties under different deformation strains was also carried out, to analyze the effect of EMS on Cu-Cr-Zr alloys. The experimental results showed that the Cr dendrites tended to be smaller and shorter in Cu-10Cr-0.1Zr alloy solidified with EMS (16Hz, 100A). Since electromagnetic stirring have the role to break dendrite,it’s beneficial to increase the amount of dendrites and decrease the size of dendrites. The tensile strength of Cu-10Cr-0.1Zr wire solidified with EMS was higher than that solidified without EMS.

In this paper, the mechanism of radio frequency (RF) causing fire and explosion directly and indirectly was recommended, studies of RF risks in flammable and explosive environments were summarized, some problems in RF risk researches recently were discussed, study prospects of RF risks in flammable and explosive environments were analyzed. The fact that the mechanisms and conditions of RF igniting combustible gases should be researched by more deeply theories and technological means, and that RF security standards should be laid down and a complete and precise RF security assessment system should be established in flammable and explosive environments was put forward.

In light of the special topography in loess gully areas, the mining subsidence disasters in which are classified into three types. The evolution process and formation mechanism of each subsidence type are analyzed, and puts forward corresponding control countermeasures. The collapse disaster is considered to be caused mostly when tensile stress in rock or soil exceed their tensile strength, while the landslide disaster is mainly initiated when shear stress exceed the shear strength. The slumping disaster, however, possess both the tensile failure and the shear failure mechanism. Methods of reducing damages such as coordinated and height-limit mining, designing protective coal pillar, backfill mining and mining down the slope can be adopted to prevent mining subsidence disasters in gully influence scope. Control measures such as slope cutting, crack grouting, collapse backfilling, support and reinforcement, planting vegetation are meanwhile needed. Measures for the restoration and emergency management must be taken after the disaster.

In order to analyze the stable organic carbon isotope characteristics and the causes of anthrax lite, 14 samples, containing hydrocarbon source rock, rock and anthrax lite, were selected to test the stable organic carbon and organic nitrogen isotope. Results showed that the relations of stable organic carbon isotope between source rock and anthrax lite were that δ13C source rock

In order to demonstrate the synchronous driving capability of multi-servo motor, an improved synchronous drive control platform based on DSP used in teaching was established. The dedicated motor control chip ASIC-TMS320F2812A was adopted with a unique independent PWM control signal output function. The hardware components were introduced, resulting in principle and duty cycle of the PWM waveform calculation. The tests showed that the DSP servo control system has good performance of high reliability, fast dynamic response and low noise.

Recently, indoor localization is essential to enable location-based services for many mobile and social network applications. Due to fluctuation of the wireless signal, the accuracy of a simple WiFi fingerprint-based localization is not high. In this paper, we first exploit Pedestrian Dead Reckoning (PDR) technology to overcome the problem of the wireless signal fluctuation, then propose a PDR-aided algorithm with WiFi fingerprint matching for indoor localization, which using the PDR technology aided indoor localization. Experiments show that our algorithm has better accuracy than other indoor localization methods.

The traffic control problem is a hot issue in recent years. We investigate the effectiveness of three traffic rules in assuring safety and improve traffic flow. We utilize a cellular automata method of traffic flow to investigate and simulate the vehicle performance and use a linear weighting approach to weigh safety and traffic flow comprehensively. We establish overtaking models of a two-lane freeway on the basis of the stochastic traffic cellular automaton (STCA) model. Using the cellular automata method, we simulate the relationships between the traffic flows, the average vehicle velocity, and the vehicle density. We propose two new traffic rules, which in the premise of ensuring safety and improve traffic flow.

This paper analyzes the influence of ChangJiu High-speed Railway on power quality. Compared with the traditional AC-DC electric locomotive, AC-DC-AC electric locomotive has been widely used in High-speed Railway which harmonic content decreased significantly, power factor also improved. Based on the RTDS simulation, voltage sags have not been caused when electric locomotive is starting.

In this study, reactive processing of maleated polypropylene with different types of amine modifiers, including 1,12-diaminododecane, tetraethylenepentamine, p-phenylenediamine, and 1,6-diaminlhexane were carried out. The changes in melt viscosity, molecular weight and its distribution, as well as crystallization were measured and discussed. All the modified samples exhibited increased molecular weight and enhanced branching structure compared to the virgin maleated PP. Aniline modified sample exhibited the highest weight average molar mass., while polyamide-modified maleated PP showed the highest degree of branching. It was also noted that all of the amine-modified samples showed higher crystallization and melting temperatures than that of the unmodified sample.

In order to improve gas drainage of soft and outstanding coal seam in Huainan mine area, for eliminating outburst hazard, hydraulic fracturing is applied at west one (13-1) rock cross-cut coal uncovering face. By analysising antireflection mechanism of hydraulic fracturing, hydraulic fracturing is designed and construct at rock cross-cut coal uncovering face, and then investigate the effect of hydraulic fracturing, at last it get a hydraulic fracturing complete set of technical system.

A new design of automated guided vehicles control system is presented, which applies wireless sensor network (WSN) communication technology to make vehicles work as mobile robots with distributed sensing ability, meanwhile uses swarm intelligence algorithms to coordinate the vehicles. Compared to the traditonal system, this system is more flexible because that it is an infrastructure-free system with WSN to assist locating and navigating, and it is suitable for the dynamic industrial applications with self-organization network communication and swarm intelligence control.

Against the State Grid Corporation of integrated demonstration project pilot project Gong qing smart grid demonstration project 1.5MWp rooftop PV projects access, combined with the actual situation, combined with the ETAP software features of advanced power quality analysis , first proposed using ETAP software for power quality analysis and evaluation of two kinds of access solutions , to establish the model flow calculation example, three different nodes of the short circuit calculation and harmonic calculations for the power sector access system designed to provide a reference.

ANSYS14.0 structural analysis software is used in order to make a ring rib-reticulated shell for the overall stability analysis. Considering the geometric nonlinear analysis and initial geometric imperfections influence , obtain a key node of the load - displacement curve and assess the ultimate strength of the structure. The results showed that: the structure meets the "Space grid rules" for monolayer shells stability requirements. And it is found that load distribution form and initial geometry defect has a great deal whit bearing capacity of single-layer lattice shell stability by comparison.

The new mullite-SiC bricks were prepared by mullite homogenized grogs to substituted the bauxite clinkers (Al2O3content is 85% or 88%) as raw materials. In this paper, the physico-chemical properties and wear resistance of the new mullite-SiC bricks were studied by comparing with the ordinary mullite-SiC bricks produced by using bauxite clinkers as raw materials. The result shows that the new mullite-SiC bricks have low apparent porosity and bulk density, high compressive strength and refractoriness under load, excellent wear resistance. The mullite homogenized grogs can substitute the bauxite clinkers as materials to produce mullite-SiC bricks and improve the properties of the bricks.

The ability of acquiring and processing information in manufacturing influences agile of manufacturing system. According to the idea that networked field information processing is realized based on intelligent nodes of field-bus technology, distributed intelligent field information processing flow is researched to synthesize multiple functions such as information gathering, information processing, warning system and field control. The method of information represented and collected was put forward. The multilayer data fusion model of distributed intelligent field information processing is built. Then the distributed LonWorks fieldbus monitoring model (DLFMM) based on LonWorks fieldbus technology is established. A monitoring system of a rail vehicle automatic door factory is shown as an example to illustrate design strategy of monitoring system based on DLFMM. This monitoring system shows that the model of distributed intelligent field information processing, DLFMM and the extraction and representation of information flow discussed in this paper are reasonable and applicable.

Yellow colored anatase Fe/N co-doped TiO2powders have been successfully synthesized by one step hydrothermal method at a lower temperature. The grain size was about 10 nm and the specific surface area of the powders ranged from 160 to 166 m2/g. The light absorption of Fe/N co-doped TiO2powders was enhanced in the visible light region of 400~500 nm and a new absorption peak at about 470 nm appeared when the Fe/Ti ratio exceeded 0.5%. The visible light photoactivity of Fe/N co-doped TiO2powders has been greatly improved than that of un-doped TiO2powders under visible light irradiation.

A series of bis (2-tetrahydrobenzofuranyl) alkanes in good yield under solvent-free conditions from differently aromatic substituted aldehydes and 3-methyl-6,7-dihydrobenzofuran-4(5H)-one in the presence of H2SO4•SiO2as catalyst at 90oC. Their structures were characterized by NMR, IR and ESI-MS. The proposed mechanism for the H2SO4•SiO2-catalyzed condensation reaction have been discussed in the work. This versatile approach has the advantages of broad functional group compatibility, short reaction times, simple operation and environmentally benign nature.

TiO2 thin films were prepared on SiO2-coated glass substrates using sols deriving from high concentration titanyl sulfate solution by the spin-coating technique. The calcined films were characterized by X-ray diffraction, UV-Vis spectroscopy, scanning electron microscopy. The film exhibited high transmittance in the visible light region and high absorption in the ultraviolet region. The contact angle of SiO2/TiO2 decreased to below 5° under 30 min of UV light irradiation and can sustain for 1 weeks.

The mold strains with stronger ability producing aroma were screened from 15 mold strains of the laboratory, and the culture conditions were optimized. The result showed: the strains njsys-6, njsys-45, njsys50 had stronger ability producing aroma. In koji juice medium, the strains had the most abundant metabolites, the esterifying enzyme activity and total ester content were the highest for 7.19U/mL and 0.18%. Njsys-45 could resistant high concentration ethanol and temperature up to 10% and 36°C respectively, it could resistant pH3.6. It had been confirmed that njsys-45 strains could be added aroma substances in Koji, and the esterifying enzyme activity was 7.18U/mL, the total ester was 0.18%.

Through analyzing the structure of the alluvium and bedrocks, a discrimination method of main influence factors of surface subsidence was proposed, and the discrimination formula was put forward. Taking the overburden and ground surface of the large cutting height working face in Bin Chang mining region as the research object, the structure and location of key stratum and the structure of the alluvium was analyzed. Besides, through the surface monitoring, the parameters of ground movement and deformation was given, and the discrimination method was verified to be correct. Furthermore, using numerical simulation, the alluvium and bedrocks influences on the surface subsidence under different mining width were studied respectively; the ground movement and deformation characteristics under the influence of alluvium and bedrocks were put forward. The study has provided a basis for the prediction of surface subsidence under certain conditions.

A quenched surface was applied in flow boiling, which is fabricated by quenching a piece of copper in carbon nanotube (CNT) fluid.Its performance was compared with bare copper, and the results showed that the quenched surface can enhance the heat flux by 15–20%. Quenched surface was less effective in enhancing heat flux as the flow rate and liquid subcooling was increased.

Local support vector machine gives the feature same weight in classification. In fact, many datasets have some weak or irrelevant features related to the classification. Thus giving features same weight may reduce the classification accuracy of local support vector machine.This paper puts forward a new local support vector machine that the feature weight is optimized by PSO (Particle Swarm Optimization), it is tested on the international standard UCI data sets and the images of tree taxonomy data sets, the results show that the accuracy of the algorithm we proposed is better than the general local support vector machine.

By analysis the form of gas percolation in coalfield fire, the follow conclusion is obtained : under the influence of natural wind pressure and fire pressure, natural ventilation system of coalfield outcrop is formed automatically during coal spontaneous combustion, which exists in two forms, one is the fresh airflow percolation in caving zone and its pore, the other is coal combustion gases migration movements in cracks after sliding. The fluent numerical simulations show that natural ventilation system in coalfield outcrop fire district is a vacuum ventilation system; From inlet to combustion area air intake line, air pressure and gas percolation on linear relationship, and gas percolation meets Darcy law in the porous medium percolation theory.

With the rapid grow of the volume of data and internet application, as an efficient and promising infrastructure, data center has been widely deployed .data center provide a variety of perform for network services, applications such as video stream, cloud compute and so on. All this services and applications call for volume, compute, bandwidth, and latency. Existing data centers lacks enough flexible so they provide poor support in QOS, deployability, manageability, and defense when facing attacks. Virtualized data centers are a good solution to these problems. Compared to existing data centers, virtualized data centers do better in resource utilization, scalability, and flexibility.

Aiming at the face roadway 22109 of Cuncaota coal mine, using FLAC3Dnumerical simulation software, 19 of 5 groups about bolt and anchor combined support schemes were analysed and compared, and the reasonable scheme of φ18×2000mm thread steel bolt and φ17.8×6500mm anchor cable combined support was obtained. Support result of this scheme was analysed with FLAC3Dsoftware, the result show that this scheme can support the roadway effectively. Practical application show that this scheme can achieve the security, economical and effective support result, and can be used in this type of roadway.

With the development of distributed generation technology rapidly, a large number of wind, solar and other renewable energy access to access system . Since renewable energy is intermittent and stochastic, which posed economic dispatch system a serious challenge. Consider the system operating costs and sewage expenses, the paper constructs multi-objective micro-grid system economic dispatch model composed by the wind turbine, diesel engine, battery and load. And through MATLAB / Simulink simulation, model is established to verify the correctness and effectiveness.

New production techniques need to be developed in the clothing industry to satisfy the demands of customers. In this paper, a new algorithm, which can transform 3D surface of the prototype garment to 2D cutting pattern, was developed. The corresponding feature points with 2D prototype pattern were defined manually using 3D cursor on the body in advance. Further 3D wireframe of garment prototype was created by connecting feature points. The final pattern of the prototype was obtained by flattening geometrically 3D wireframe of each zone. The visual assessment was also made and proved the algorithm validity. This approach improved the flattened pattern practicality.