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Comprehensive analysis on the requirement and evaluation result of pipeline steel for sour service is carried out in this paper. So as to provide technical support for the development of the high toughness sour service pipeline steel with low manganese content.The evaluation results shows that the high toughness sour service pipeline steel with low manganese content has excellent comprehensive properties, and the excellent comprehensive mechanical properties and corrosion resistance properties of trial products are achieved through reasonable composition and micro-structure design. The HIC and SSC test result complies with pipeline steel requirement for sour service drafted by major international manufacturers. In order to guarantee the application prospect of the trial products, the weldability of the sour service pipeline steel is analyzed finally, and the test result shows that HAZ softening can be improved when the cooling rate was higher than 20 °C /s.

UHVDC transmission could deliver high-power electricity over long distances effectively, while the DC stray current led to corrosion of grounding device and the surrounding buried metal during the operation inevitably. This paper reviewed the research progress of HVDC corrosion at home and abroad in recent years. It elaborated corrosion research direction of HVDC system from three aspects, which were pole, grounding grid and the neighboring tower grounding body buried pipeline respectively. Describing the anti-corrosion measures on grounding devices and buried pipeline, and explaining the advantages and defects of various anti-corrosion technology. At last, we proposed that it was necessary to expand the research in UHVDC field, grasp the erosion rule of DC stray current in soil comprehensively to enhance the security of UHVDC transmission system of national grid.

In this work, vertically aligned TiO2 nanorod arrays (NR) are synthesized directly on FTO coated glass substrate by hydrothermal method. The samples are characterized by XRD, SEM, TEM and the results indicate that the 1-D nanorods are of single crystal rutile structure with growth direction along the [001] direction. The morphology (diameter, thickness and density) of the nanorods can be adjusted by changing the precursor amounts. The possible growth mechanism of TiO2 nanorods on FTO substrate has also been briefly discussed in this work. For dye-sensitized solar cells (DSSCs) fabricated of different thickness nanorods, a power conversion efficiency (PCE) of 1.74% has been achieved by using ~3μm nanorod arrays under simulated AM 1.5 illumination (100 mW cm-2). It is expected that the 1-D nanorods can be composited with other nanomaterial of different structures and morphologies to enhance the efficiency of DSSCs.

The scanning process of fused deposition modeling is realizing the fill of certain region, Therefore, reasonable scanning path planning directly affects the forming efficiency and the precision of the work piece. The method of Hilbert curve fractal scanning path which basing on the characteristics of both partition and parallel scanning is put forward basing on the analysis of the existing scanning mode. Application of improved curve filling method for complex curved surface forming planning, according to the characteristics of the Hilbert curve and Hamilton circuit, combined with the characteristics of the scanned level scan path trajectory planning, generate a continuous and comprehensive function value which the weight minimum scanning track under the premise of ensuring the quality of scanning. In order to avoid the generation of island type trajectory, setting a decimal for each loop can easily distinguish between each circuit, finally obtains the scan trajectory. The method can be used to generate scanning track continuous greatly reducing the spray head start and stop times and improves the processing efficiency of the whole, not only to meet the accuracy requirements and can generate non scanning path interference but also high forming efficiency.

This paper analyzed the morphology and reasons of pitting corrosion perforation of 0Cr18Ni9 stainless steel cooling water pipes in a power plant and pointed out the measures to prevent the pitting corrosion under this condition. The results showed that: the reason of pitting corrosion of 0Cr18Ni9 stainless steel cooling water pipes was the existence of multiple Cl-and easily fouling Ca2+ and Mg2+ in water, with the corrosion products mainly the oxides of Fe and Cr; the economic measures to prevent pitting corrosion were to increase the pH of water and decrease the content of Ca2+ and Mg2+.

The reasonable distribution of the video monitoring points in the substation is one of the technical problems to be solved in the engineering. We combined the camera calibration algorithm with the real application of the substation video monitoring point layout, and proposed a nonlinear camera calibration method of the external parameters based on the 3D real scene, which is suited for the substation video surveillance system. The optimal video monitoring points are determined by the relationship between the video produced by the camera movement and the visual scope displayed with the 3D real scene, and testified by the location of each object through its boundary geometric element shown in the pictures. It has been proved applicable by the video simulating analysis on the 110kV main transformer monitoring points. This method has been used in the engineering design of the Guangdong Power Grid substation video surveillance system.

In this paper, I designed a differential planetary gear for flip climbing transmission system which was applied to the star-climbing wheelchair. According to space limitation and the stair climbing per formance requirements, distributing the number of teeth for each gear under transmission ratio requirements. Furthermore, modifying tooth profile parameters on each gear for improving the quality of the transmission. Using SolidWorks software established t he three-dimensional model. Then impact and contact simulated analysis is studied based on the SolidWorks Motion Plugins to get transmission and meshing condition. At the same time, gave the SolidWorks Motion output data as a result of the input data to t h e SolidWorks Simulation. Through the simulation results validate the output center gear tooth can meet the carrying capacity requirements. On the other hand, it also provides theoretical basis for further improve the structure design.

In order to study the temperature field distribution in the process of machining, the finite element theory was used to establish the orthogonal cutting finite element model, and the key technologies were discussed simultaneously. By using ABAQUS software for cutting AISI1045 steel temperature field of numerical simulation, the conclusion about changing rule of cutting temperature field can be gotten. The results show that this method can efficiently simulate the distribution of temperature field of the workpiece, cutter and scraps, which is effected by thermo-mechanical coupling in metal work process. It provides the theory evidence for the intensive study of metal-cutting principle, optimizing cutting parameters and improving processing technic and so on.

Hybrid technology has already been recognized as the direction of energy conservation and reduction by world, thus it has drawn the universal concern of Engineering Machinery enterprise and the researchers. Loader as the representative of construction equipment for its high quautity and broad application over the market. In this paper, based on the categories of the hybrid power loader and combined with the latest research achievements at home and overseas,the research status of hybrid power loader has been summarized,while pointing out the problems in the development of hybrid power loader.Besides,the text also analyzes the development trend of hybrid power loader.

The extended finite element method (XFEM) is a numerical method for modeling discontinuity such as cracks, holes, inclusions etc within a standard finite element framework. In the XFEM, special functions which can reflect the problem’s solution characteristics are added to the finite element approximation using the framework of partition of unity. Compared with the standard finite element method, it obtained more accuracy without remeshing. In this paper, we studied crack propagation behavior under different proportions of tension and shear loads by XFEM.

In this paper, a new analysis model to assess the structure seismic capability is established, using improved capacity spectrum method. The model can solve the problem of many unknown and big computation workload in the process of conventional Pushover analysis. Conventional Pushover is very complex when use in the analysis of structure dynamic problem and nonlinear problem, the new model can solve these problem.

In order to effectively predict aspects of tunnel deformation, taking effective and timely measures against the problem to ensure the safety of tunnel ,LS-SVM-MC model is proposed . Namely, Markov chain based on LS-SVM corrects the error, and ultimately improves the accuracy of prediction. By the analysis and calculation of deformation prediction of a tunnel , you can find that the method is more in line with the actual situation, showing predictive superiority and a high prediction accuracy.so the method can serve as a new ways of tunnel deformation prediction,some promotional value can be gained in later work.

Based on UDP protocol in Visual Basic Winsock control, this paper designed third-party software to send and receive data. Wireless data transmission module used CM3160EP module. In order to decrease wireless data loss rate, four kinds of packets format is designed. The results show the stable data transmission and verify the send-receive and display of hexadecimal data on server-side.

By analyzing the pavement hydraulic power generation system working principle and accumulator mathematical model, full account of the system actual operating conditions, use Matlab/Simulink software simulation the accumulator working process, obtain accumulator absorbs shock pressure effect with accumulator body parameters and working parameters relationship.

The present study was designed to determine the anti-hypoxia and anti-fatigue effects of Ganoderma lucidum polysaccharides (Gl-PS). The anti-hypoxia effects were evaluated by survival times of mice under anoxic condition of ordinary pressure. The anti-fatigue effects were evaluated by exhaustive swimming times of mice, and some biochemical parameters related to fatigue were measured. The results showed that Gl-PS could prolong survival and exhaustive swimming times, decrease blood lactic acid (BLA) and blood urea nitrogen (BUN) contents, and increase the liver and muscle glycogen contents of mice. Gl-PS had anti-hypoxia and anti-fatigue effects.

The pile-soil dynamics is an interdisciplinary studies of structural, geotechnical and vibration engineering in the existing bridge. Traffic load model, the developments and status in the existing bridge were reviewed and introduced. The main content and characteristic of pile were summarized in clay, sand, silt and red clay. Main problems existed in the study of cyclic loaders on the piles were discussed. The prospect of future research trend in this field was also examined.

In view of the extraction of liquid crystal from the wasted LCD panels, this paper aims to analyze the raw materials consumption, energy consumption and emissions to the environment in the extracting process based on the method of Life Cycle Assessment (LCA). The environmental impacts of the recycling procedure are assessed with the aid of LCIA（Life Cycle Inventory Assessment）method and CML2001 method provided by LCA analyzing software Gabi 4. Two ways of liquid crystal extraction mentioned in the paper are supercritical method and distilling method. The assessment results indicate: the supercritical method’s LCIA result is 3 times higher than the distilling method, but the liquid crystal extracting rate can reach 95% with a lower raw materials consumption; the environmental impacts of distilling method is lower than supercritical method, but its extracting rate of liquid crystal can only get to 50%. For industrial applications, supercritical method has greater advantages and there are more crafts to perfect for distilling method in improving the recovery rate of liquid crystal.

A method to analyze the shape of three-dimensional curve surface for flexible rolling forming metal plate is proposed based on the traditional rolling and multi-point adjustment technology. It has smaller rebound and better forming in comparison with the traditional method which is using the surface deformation. The simulation experiments are implemented using the developed experimental device to demonstrate the feasibility and practicality of the flexible rolling forming. The proposal could be used in the various industries.

The LDS is the most advanced and efficient technology in the MID (molded interconnect devices) electromechanical integrated device manufacturing technology. In this paper, the key technologies about modeling of LDS equipment, kinematic analysis of the machine system and optical system and how to combine them to achieve simulation were introduced, the MID modeling and simulation system for LDS equipment was developed based on Open CASCADE, The method of building the component tree was used to achieve the design of the main of the device. By adding the component model and defining the position and sports relationship, completed the three dimensional modeling of main structure and established the motion model. And combined with the MID cellular antenna model, the simulation of the laser machining process about the product has been completed on this system. The result verifies the validity of the simulation system.

In this paper, a classical wall-jet-flow loaded with particles is simulated by the finite analysis /grid method using the particle PDF transport equation, as well as by the finite analysis / particle method, and then the simulation results ​​obtained by the two methods are compared with the experimental results. It is shown that the finite analysis/grid method is effective for the prediction of the particle flow.

With the rapid development of the technology of liquid crystal display, LCDs have become the main stream displays. However, if there are no appropriate ways to recycle the discarded LCDs, the environment will be polluted and the resources will be wasted. TFT-LCD panels mainly consist of the color filter (CF) substrate and the thin film transistor (TFT) substrate which both have a surface covered with indium-tin oxide (ITO). ITO layer contains the metal of indium which is rare, precious and of high value. In view of the difference of the structure and material of the CF substrate and TFT substrate, an efficient and green process has been presented for recycling the indium by means of theoretical analysis and experimental verification. Under heating condition, the sodium hydroxide solution is used to dissolve the color filter of the CF substrate and the ITO layer attached to the color filter can be eliminated quickly and the metal indium can be enriched by filtering solution. By grinding the ITO layer on the TFT substrate with the aid of water-proof sand paper and collecting ITO scraps, indium can also be enriched quickly. The experiments show that the indium content of the CF substrate and TFT substrate are both quite low. Enriching indium on the premise of not dissolving indium is beneficial to the concentrated recovery of indium and is helpful to raise the recycling efficiency and protect the environment.

In order to meet the requirements of high stability, high vibration resistance, energy saving and environmental protection and long service life for the railway vehicle car lighting system, this paper designed a LED (Light Emitting Diode) lighting control system suitable for railway vehicles car. Using IPC for the principal computer, microcontroller for the subordinate computer, CAN bus as the communication network. Multiple brightness sensor collect the brightness information of car environment. According to the characteristics that the LED is suitable for high frequency switch power, using PWM technology, the current though the LED light can be control. ATmega16 microcontroller as the control core can automatically to adjust the brightness of the car according to the change of external environment, it ensured that the LED light emitting uniform and stable so that this kind of control system has very high application value.

Because of the communication distance, the more nodes, the requirements of high real-time, LED lighting control system for railway vehicle carriage chooses Controller Area Network (CAN) as the communication mode to achieve centralized control in all carriages. Illuminance gathered from multi-sensors which were installed on the surface of the carriages was feed back to the Industrial Personal Computer (IPC). And then, through the incremental PID control algorithm, the IPC achieve the brightness of the lighting system intelligent control for vehicle consulting brightness intensity which according to the external environment. Experiment shows that this method is practical and effective.

in this paper, a finite analysis/grid method for high-dimensional PDF equation of fluid mechanics of two phase flow is proposed. The particle high-dimensional scalar PDF transport equation in position-velocity phase space is reduced to velocity phase space and position phase space. An analytical solution of the particle velocity PDF is obtained by Fokker-Planck techniques, the particle position PDF is solved by finite difference method, which determines the distribution of particles in two-phase flow. It is shown that the Finite Analytic/Grid method can simulate the two-phase flow very efficiently.

Domestic researchers paid attention to the ecological society, on the basis of defining the concept of ecological society, they did many researches on analyzing the features, dividing the stage and searching the path, and acquired some theoretical results.We sort out their researching achievements and find there are still some problems.

A composite control strategy is proposed based on the repetitive control and deadbeat control in the ups inverter control system, according to the features of the non-static error track of repetitive control and the deadbeat control’s fast response and high precision control. Repetitive control can be very good to eliminate periodic disturbance, and deadbeat control to reduce the overshoot and oscillation, when the system is subject to greater disturbance, that can improve the dynamic performance of the system. Simulation results show that it has a fast transient response, high accuracy, THD and other small features.

To study the magnetic-electrical-mechanical coupling mechanism of microwave ME (magnetoelectric) tri-layered structures, we proposed a theoretical model of electric tunable FMR (Ferromagnetic Resonance) frequency shift for bias magnetic field in different directions through the theory of Smith-Beljers and free energy density of ferrite. A deformation produced by the applied electric field called strain could be obtained through the theory of classical laminated plate. This model effectively predicts the stress of laminated structure increases when the piezoelectric coefficient increases, the shift of electric field tunable FMR frequency is more obvious when saturation magnetization and magnetostriction coefficient of ferrite increase. Moreover, it qualitatively explains the experimental phenomena that the directions of FMR frequency shift are opposite when apply the in-plane and out-of-plane magnetic field respectively, and provides a theoretical basis for electric field and magnetic field dual tunable microwave devices.

A series of waterborne cationic polyurethanes dispersions (CWPU) was prepared through prepolymerization method by reacting polyethylene glycol (PEG1000) and isophorone diisocyanate (IPDI) with N-methyl diethanol amine (MDEA) as chain extender. Then FeCl3 was employed as oxidant, therefore CWPU/polypyrrole (CWPU/PPy) conductive composite was prepared by in situ chemical oxidative polymerization of pyrrole (Py) in CWPU dispersions. Effects of molar ratio of FeCl3 to Py, Py concentration on the resistivity of the CWPU/PPy composite films were investigated. The structure, morphology and thermal stability were also characterized by Fourier infrared spectra (FT-IR), light scattering, TEM, and TGA. FT-IR demonstrated the presence of hydrogen-bonding interactions between CWPU and PPy. The average particle size of CWPU/PPy increased from 10.61nm to 30.29nm compared with pure PU, and corresponding size distribution decreased from 0.850 to 0.346. It was also found that CWPU/PPy displayed as spherical morphology, and no aggregation among particles was detected among particles. TGA certified CWPU/PPy was endowed with better thermal stability. In addition, conductivity stability of composites films was also studied. It was found that composite films not only displayed low resistivity but also improved conductivity stability.

A statistical method of particle size distribution is researched in order to measure the mineral blasting effect. Aimed at resolving the problems of sensitivity to noise and over-segmentation existing in the traditional watershed algorithm(TWA), a improved watershed segmentation scheme based on morphological reconstruction and mark extraction is presented. Firstly, two-stage grayscale morphological reconstruction (TGMR)is employed to filter the image. Secondly, the watershed seed area and the watershed line area are pre-calibrated in the gradient image. Finally, the watershed transformation(WT) is conducted so as to further eliminate over-segmentation. Simulations show that the method can effectively remove the noise jamming and restrain the over-segmentation. It is also able to accurately locate the ore region contour in order to improve the segmentation results.

Climate change is a world-wide problem. The paper analyzed the global climate change characteristics, and put forward that the most important reason in recent years is human activities through many analysis. Then introduced the international negotiations of climate change and summarizes the international experiences that china can learn from.

In order to improve the safety of road hazardous goods transportation and decrease the accidents, the management process of hazardous goods transportation is taken as the main research object in this paper. The fault tree is established to seek out the primary factors influencing on the hazardous goods transportation on road, and the safety proposals are presented.

Exampled by a test project in Kuche - Akesu express highway engineering of Xinjiang Uygur autonomous region in this paper, it is analyzed that technical and economical rationality of backfilling at bridge abutment with the natural graded gravel mixed with cement of flow state, and the evaluation parameter is introduced by contrast of test projects between conventional technology and the new technology. It lays the foundations of the promotion and development of this technique and the further study.

This research focused on the numerical simulation of electric field tuning characteristics of the magnetoelectric microwave devices with the core of the laminated ferrite-piezoelectric magnetoelectric materials. Firstly, we proposed an expression for the shift of ferromagnetic resonance (FMR) frequency tuning by external electric field in piezoelectric layer, then substituted the expression of magnetoelectic (ME) constant into this expression, which can convert the electric field tuning on the laminated magnetoelectric materials into the equivalent magnetic field tuning on the ferrite layer. Secondly, we built a numerical analysis model for tunable magnetoelectric microwave device which is formed by the laminated magnetoelectric material and microstrip line, and put the equivalent magnetic field into this numerical model, then the numerical analysis model of novel tunable magentoelectric microwave device is completed. Taking a tunable ME microwave resonator for example, the S parameters calculated by the numerical model in this paper are in good agreement with experimental results both qualitatively and quantitatively. Considering the demand for the designing and applying of the microwave devices, we studied the effect of geometrical dimensions of the ferrite layer (YIG/GGG) on the return loss and the resonance frequency.

Security of computer information system more and more aroused people’s attention, and information security assessment and computer system security model is closely related to information security model which is patricularly important. This article describes the security model of the characteristics and uses, and several security models are compared, these models were from a different perspective considering system security, through comparison Analysis, Establishment of information security model obtained several important aspects to consider.

Influence of sub-temperature quenching temperature on the tensile strength, hardness and toughness of 35CrMo steel was studied. The microstructure characteristics of this steel after sub-temperature quenching were analyzed. The results showed in the range of 780~810°C the strength and hardness of the 35CrMo steel sub-temperature quenched increased with quenching temperature increasing, reached the highest strength and hardness at 800°C quenching and then began to decrease, while its elongation decreased with the quenching temperature increasing. The duplex microstructure of martensite and ferrite was obtained by sub-temperature quenching of 35CrMo steel. With the quenching temperature increasing, the ferrite content decreased and the distribution of ferrite morphology was changed. A small amount of strip ferrite existed in lath martensite lamellar when quenching temperature was 800°C and the impact toughness of 35CrMo steel was better than that of conventional samples 850°C completely quenched.

API external upset (EU) tubing connection was applied extensively, which could ensure the enough joint strength. The end upsetting of EU tubing was the complex forming process containing upsetting, expanding and extruding, which played the important role in the EU tubing manufacture process. In this paper, the numerical simulation of end upsetting process of EU tubing was performed, which was helpful for optimization of technical process and mould.

With the continuous integration of computer, networking and wireless communications industry in technique and management, information technology has entered the era of rapid replacement, as well as competition among electronic information industry is becoming more and more intense. Owning the patent is a major element to win in the current competition of electronic information industry. Therefore, it is more important to establish and improve patent management system, and implement patent strategy in the industry.

Simulated heat affected zone continuous cooling transformation curve was measured by means of Gleeble 3500 thermal simulator. According to the results of microstructure observation and hardness measurement, influence of cooling rates on the microstructure and hardness in coarse grain zone of high-strain pipeline steel X80 was studied. The results illustrated that softening in coarse grain zone was ubiquitous problem for high-strain pipeline steel X80. There were mainly four types of phase transformation in coarse grain zone of high-strain pipeline steel X80. Polygonal ferrite(PF) and a small quantity of pearlite, granular bainite, bath bainite and bath martensite were obtained after different cooling time.

The pretreatment process is quenching and normalizing, respectively. Influence of different original structures on tensile strength and hardness is investigated. The experimental results show that the as quenched 35CrMo steel by zero time holding quenching obtains fine lath martensite structure and has higher tensile strength and hardness. The mechanical properties of the as quenched 35CrMo steel is better than that of the as normalized 35CrMo steel. The effect of original structure on the mechanical properties of 35CrMo steel is prominent when the zero time holding quenching temperature is lower, but it decreases with the quenching temperature increasing. The austenite inverse transformation zero time holding quenched at low temperature can improve the mechanical properties of 35CrMo steel.

The state council about speeding up the development of tourism opinion clearly put to greatly promote the tourism industry of energy saving and emission reduction, five years to star hotel, A level scenic area water electricity consumption by 20%. This has long been called is low carbon industry for tourism, facing a great challenge. This paper by analyzing think though tourism is low carbon industry, still has certain reduction space, can from the government and industry management department, tourism management department, tourists in such aspects as take effective measures to achieve a low carbon tourism, promote energy conservation and environmental protection.

Microstructure and electrochemical characteristics of La0.35Ce0.65Ni3.8-xCo0.8MnxAl0.4 alloys have been investigated. X-ray diffraction results indicate that the alloys consist of a single phase with CaCu5-type structure, and the lattice parameters a, c and cell volume V increase with increasing x value. The maximum discharge capacity of the alloy electrodes first increases from 217.9 (x = 0) to 290.1 mAh/g (x = 0.3), and then decreases to 271.3 mAh/g (x = 0.5). The high-rate dischargeability at the discharge current density of 1200 mA/g first increases from 58.4% (x = 0) to 78.2% (x = 0.3), and then decreases to 75.2% (x = 0.5). Both the charge-transfer reaction at the electrode/electrolyte interface and the hydrogen diffusion in the bulky alloys are responsible for the high-rate dischargeability. Cycling stability first increases with increasing x from 0 to 0.3 and then decreases when x increases to 0.5.

Based on the character of the penetrated cracks in the sluice piers of a overflow dam, the reasons inducing cracks are investigated. The results of the finite element (FE) nonlinear analysis on a representative cracked sluice pier indicate that the current cracks will expend, and the piers need to be strengthened. Four strengthening schemes with prestressed anchorage cables are designed, and their effects are analyzed and compared with FE method, the best strengthening scheme is found.

This paper investigate the mechanical property and microstructure of girth weldment of Lan Zhou to Cheng Du crude oil pipeline. The welding joint was bottomed by cellulose electrode E6010 and filled and covered by flux-cored wire AWS A 5.29 E71T8-Ni1. According to SY/T 4103-2006, test results show that the selected process parameters and welding method take on outstanding performance .Microstructure of weld joints is acicular ferrite, polygonal ferrite, proeutectoid ferrite and granular bainite, and widmanstaten ferrite dosn’t exsist in heat affected zone(HAZ). Microstrure of the whole weld joint is mainly polygonal ferrite and granular bainite, this is the reason that mechanical properties can meet the Lan Zhou to Cheng Du crude oil pipeline project requirement.

The dynamic mechanical behaviors of as-cast sour service drill pipe steel under development during hot deformation were studied in this paper by using Gleeble-3500 thermal mechanical simulator. The compressions were carried out at the temperature of 900°C, 1000°C, 1100°C, 1200°C and strain rates of 10s-1, 1s-1and 0.1s-1. The compress degree was about 70%, and then the maximum true strain for each specimen was 1.2. The experimental results show that the peak stress was related to the compression temperatures and the strain rates. Through respectively analyzing and studying the true stress-true strain curves, the hot deformation constitutive equation and the deformation activation energy were obtained by regression analysis. The evolution of microstructures at various strain rates and temperatures was discussed. Experimental results can provide scientific basis for analyzing the hot deformation processes and controlling quality. Keywords: sour service drill pipe, hot compression, true stress-true strain, constitutive equation, microstructure

In order to study actual work performance of the external pre-stressed combination box girder with corrugated steel webs, and to analyse the integral stress of box girder influenced by the corrugated steel webs, and understand the construction of the type combination box girder, this document studied the model test of the external pre-stressed combination box girder with corrugated steel webs, tried to find out the bending rule for the combination box girder and the model test result influenced by the different connections style. And the model test result was based on the assumption of “flat section” and within the elastic range, when the concentrated loads loaded on the box girder, the deflection was linear with the loads, and the corrugated slab stress was zero, which indicated the slab can not bended and the moment was supported by the top and the bottom slab, and the corrugated slab only supported the shear, and the shear lag effect only influenced local area. The conclusion of the model test will provide the reference for the bending capacity research, design and construction.

Microstructure and mechanical properties of 60Si2Mn steel by 870 °C prequenched and second sub-temperature quenching was studied. The results showed that the hardness of the 60Si2Mn steel first increased and then decreased with increasing second sub-temperature quenching temperature, and the highest hardness was obtained when sub-temperature quenching temperature was 800 °C.The sample after second sub-temperature quenching was composed of martensite and a little ferrite phase. The abundance of ferrite phase decreased with the increase in second sub-temperature quenching temperature. Fine martensite was obtained by second sub-temperature quenching, which may be relate to the grain refinement of austenitic phase and austenitic nucleation sites. The mechanical properties of the 60Si2Mn steel after 870 °C prequenching and second sub-temperature quenching are better than that of conventional samples after 870 °C quenching.

TiO2/CNTs nanocomposites with different Ti/C molar ratios were prepared by a sol-hydrolysis method at 368 K, using titanium tetrachloride as a precursor and nitrified carbon nanotubes as a support. The crystal phase, morphology and microstructure of the sample were characterized by X-ray Diffraction (XRD) and High-Resolution Transmission Electron Microscope (HRTEM). The photocatalytic activity of the samples was performed by methyl orange in aqueous solutions under UV light.The supernatant liquid of methyl orange during degradation was determined by using an UV-vis spectrophotometer (UV-vis). XRD results show that the crystal phases of the sample are composed of carbon nanotubes, anatase and rutile. HRTEM results show that the average diameter of oval titania is about 4.2 nm, and it decorates on the surface of carbon nanotubes uniformly. UV-vis results show that the photocatalytic activity of the TiO2/CNTs nanocomposite with the optimum Ti/C molar ratio is much higher than that of P25. These results indicate that a synergistic effect exists between titania and carbon nanotubes in the nanocomposite.

TiO2/Fe2O3 nanocomposite was fabricated by a hydrolysis-precipitation approach, with TiCl4 as precursor and Fe2O3 as support. The crystal phase, diameter and morphology of the sample particle were characterized by X-ray diffraction, transmission electron microscope. The results show that the samples are composed of haematite and rutile. The morphology and diameter of rutile particle, coating effect and weight percentages of haematite and rutile are related to the preparing temperature and molar ratio of Fe/Ti. The photocatalytic activity of the prepared photocatalyst was estimated in an aqueous solution at ambient temperature of 303K. The results imply that the photocatalytic activity of the sample is higher than that of phase pure rutile, related to Fe/Ti molar ratio and its preparing temperature. These results can be attribute to the microsturcture of the sample. A synergistic effect exists between titania and haematite in the nanocomposite.

In the paper, a non-API tubing connection’s sealing structure is analyzed through numerical simulation. It is very important for sealing integrity to maintain intimate and usually high contact stress of mating metal surfaces under different loading. First, the contact pressure of main sealing surface and torque shoulder surface generated by interference fit after make-up procedure is analyzed. Then, the variation of contact pressure of sealing system during the load envelope test consisting of the axial loads and internal pressure is analyzed. The analysis results can be used to optimum design and operational suitability test of non-API tubing connections.

Because of the Dynamic Drainage Consolidation method’s complexity, the dynamic characteristics of soft soil is not be described by conventional analytic method. In this paper, Numerical simulation was conducted by use of FLAC3D. And effect of reinforcement was analyzed under the different influential factors. These factors include rammer weight, rammer falling distance, rammer radius and ramming energy. Furthermore, the field test was carried out to verify the numerical simulation, the conclusions have theoretical guidance meaning for researching the consolidation mechanics and improving the construction method of Dynamic Drainage Consolidation.