Search

A removable catalyst muffler is designed and applied according to the characteristics of general 125ml motorcycle muffler. It has advantages of convenient disassembling, simpler catalyst replacement and low cost of installation and maintenance.

Now abnormal wear between brake shoe and brake drum is found easily with the bad running conditions for motorcycle. Soft tissue like ferrite and graphite in the brake drum are penetrated by the shoe fiber and falls from the surface and pushed to the inner side which causes abnormal wear. Thus material, metallographic and hardness are improved to enhance durability of the brake drum.

The velocity field and the associated tangential tension corresponding to the flow of the viscoelastic fluid over an infinite rigid plate are determined in this paper. The characteristic of the non-Newtonian viscoelastic fluid flow is analyzed using the Stehfest method of the numerical inversion of Laplace transform. It indicates that the flow of the viscoelastic fluid is very sensitive to the material constants. Finally, some comparative diagrams concerning the velocity and tangential tension profiles are presented.

As wind power in China is developing more and more rapidly, the characteristics of wind power output such as randomness and volatility have brought great pressure to the system peak load regulation. On the basis of defining negative peak regulation ability, this paper gives out the calculation formula of negative peak regulation ability including wind power and the main factors of influencing the negative peak regulation ability are calculated. Aimed at the regional power grid in the target year 2014, this paper makes some analytical prediction on such main factors and calculates the negative peak regulation ability, and the amount of the acceptance of wind power bound by it, and makes some sensitivity analysis of the negative peak regulation ability and the amount of the acceptance of wind power.

Integrating the internal and external factors of product design, this paper explore the way of the suitability of the product design and the plastic technique, and build the evaluation system of suitability of the selection of plastic technique in product design.

The 3-D turbulent particulate-liquid two-phase flow equations are employed in this study. The computing domain is discretized with a full three-dimensional mesh system of unstructured tetrahedral shapes. The finite volume method is used to solve the governing equations and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results have shown that the sand erosion rate on pressure side is more than on the suction side of the blade. The maximum value of sand volume fraction and the maximum value of sand erosion rate are at same location.

The concept of arch longitudinal beam wharf was brought out in the contemporary shipping industry of China as a result of the conflict between traditional high-piled wharfs and the increasing size of freights. Different alignments of arch axis will lead to different internal force distributions and the most dangerous section. A series of equations for the arch axis are derived through the transformation of the exponential function under a 40-meter-long span. Based on the analysis of equations affected by the combined force of uniform load and concentrated load, it is providing reference for engineers and analysts with the internal force distribution under some commonly used axis and the location of the most dangerous section for the archs.

The dynamic load on drive axle housing has great significance for analyzing the strength of drive axle housing and studying the reliability life of drive axle housing, and road roughness has an important impact on dynamic load of drive axle housing. In this paper, the drive axle housing of agricultural machinery is select as the research object. Firstly, the dynamic model of the drive axle housing is established, and the vibration equation is calculated by Laplace transform and Laplace inverse transform, and then the vibration load time history is given based on the discrete data of road roughness obtained by field experiment. At last, the rainflow counting method is used to generate the load spectrum. The study has a certain reference and application value for the optimization design of drive axle housing of agricultural machinery.

SolidWorks is a powerful, easy to use, the three characteristics of scientific and technological innovation. SolidWorks also provides a powerful API interface processing mode allows the user to write according to their own conditions and needs processing hanging with the application of the software environment. SolidWorks itself can not be drawn to the curve by curve equation operation in the corresponding module can not be achieved by drawing module drawing functions of centrifugal pump volute, here we use Visual Basic 6.0 to SolidWorks secondary development, in order to achieve parametric design of centrifugal pumps.

In granular materials processing, how to efficiently recognize and remove foreign bodies is very important. Training data including H,I mean and I standard deviation of target material are distinguished to be foreign bodies or not by training model, which is established using FWOCSVM method, while taking into account the characteristics of foreign body detection. A way to introduce the weight value reflecting the importance degree of attribute with its mean square deviation is developed to solve the problem, that is, attribute weights are not considered in OCSVM. The results show that FWOCSVM has more excellent performance than that of threshold or OCSVM .And color features adopted in the paper have excellent identification performance in above foreign bodies detection.

Dynamic compression test on TC6 titanium alloy samples have been done by using a split Hopkinson bar process and extra circuit under conditions of room temperature and high strain-rate. The effect of impressed-current on sensitivity of adiabatic shear of TC6 titanium alloy has been studied. It is shown that the impressed-current can reduce the sensitivity of adiabatic shear of TC6 titanium alloy under the condition of high strain-rate. Free electron in the samples will do direct move and take heat away from high localized area to decrease the effect of the heat. The result will help to delay formation of the adiabatic shear band. So, that is reducing the sensitivity of adiabatic shear of TC6 titanium alloy.

Fault Tree Analysis (FTA) was used to analyze the reliability of gearbox transmission system of 4LZ-2 combine harvester (4LZ-2 CHGTS). Firstly, the structure and function of the 4LZ-2 CHGTS were made a detailed introduction, and the components were divided into three kinds of A, B and C. Secondly, the Fault Tree (FT) model of the 4LZ-2 CHGTS was estabilished using the "top to down" ideology. Finally, based on the FT, the minimal cut sets (MCSs) were given and the weak link of the system was found out by the qualitative analysis; furthermore, the relative probability importance of each basic event and the reliability of the 4LZ-2 CHGTS were analyzed by the quantitative analysis. The results show that the 4LZ-2 CHGTS is of high reliability, and the fault of gears needs to be taken into a key consideration and control in the design process of the GTS.

The vortex structure of lid-driven flow in a cuboid cavity with one or a pair of moving lids is numerated using the differential quadrature method (DQM). According to the characteristics of cavity driven flow, the dimensionless governing equations and its boundary conditions used to describe the flow are established. Based on a non-staggered grid technology, the polynomial-based DQM is combined with the SIMPLE strategy to solve three-dimensional (3D) cavity driven flow. The suitable boundary condition for pressure correction equation on a non-staggered system is implemented and the continuity equation on the boundary is enforced to be satisfied. The 3D vortex structure distributions in a cuboid cavity are obtained for different Reynolds numbers and different driving modes. The analysis shows that the DQM is very suitable for the simulation of 3D vortex structure in a cavity.

An efficient method for functionalizing carbon nanotubes (CNTs) is reported, which combined HF corrosion with sulfuric acid and nitric acid for further oxidation. The X-ray diffraction and transmission electron microscopy are employed to investigate the physic-properties of the prepared catalysts. Cyclic voltammetry and chronoamperometry methods are used to study the performance of the prepared catalysts. CNTs further treated with H2SO4 and HNO3 mixed solutions with the volume ratio of 1 to 3, heating at 100 oC for 2 h, used as catalysts supports exhibit significantly improved performance towards ethanol oxidation in alkaline solutions in comparison with other decorated CNTs. The reason could be attributed to the oxygen-contain functional groups on CNTs surface can efficiently improve the interaction between CNTs and metallic particles in catalysts.

The paper presents the numerical prediction of sediment erosion on Francis turbine blades using CFD code. The 3-D turbulent particulate-liquid two-phase flow equations are employed in this study. The computing domain is discretized with a full three-dimensional mesh system of unstructured tetrahedral shapes. The finite volume method is used to solve the governing equations and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results have shown that the sand erosion rate on pressure side is more than on the suction side of the blade. The numerical simulation results are consistent with the real situation.

The paper presents numerical investigation of cavitating turbulent flow in a high head Francis turbine runner fitted with splitter blades at part load operation. Analysis was performed by OpenFOAM code. A mixture assumption and a finite rate mass transfer model were introduced. The finite volume method is used to solve the governing equations of the mixture model and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators (PISO) procedure. Simulation results show that the volume fraction of water vapor and the pressure uneven distribution on the main blade and splitter blade. It will lead to cavitation and fatigue damage.

A novel process-monitor multimodal optimization algorithm, called Pmdcopt-aiNet is given. It is based on biological immune network mechanism for process-monitor global-numerical optimization. The Pmdcopt-aiNet models can clone the process-monitor operation using dynamic cloning operation which is adopted from biological immune network mechanism. The experiments based on the multimodal benchmarks were carried out to compare the performance of Pmdcopt-aiNet with that of other existing algorithms. The experimental results in process monitoring show that the new algorithm is capable of improving search performance significantly in successful rate and convergence speed when compared with the already existing method.

The paper presents numerical prediction of cavitation erosion on a Francis turbine runner using CFD code. The SST turbulence model is employed in the Reynolds averaged Navier–Stokes equations in this study. A mixture assumption and a finite rate mass transfer model were introduced. The computing domain is discretized with a full three-dimensional mesh system of unstructured tetrahedral shapes. The finite volume method is used to solve the governing equations of the mixture model and the pressure-velocity coupling is handled via a Pressure Implicit with Splitting of Operators(PISO) procedure. Comparison the numerical prediction results with a real runner with cavitation damage, the region of higher volume fraction by simulation with the region of runner cavitation damage is consistent.

The effect of antimony on the structure, texture and magnetic properties of high efficiency non-oriented electrical steel were investigated. The results showed that antimony played an important role on inhibiting the grain growth and enhancing the fraction of favorable texture in the annealed steels. With the increase of antimony content, core loss of specimens monotonously increased and the magnetic flux density increased firstly and then decreased. The magnetic properties of specimen results showed that the magnetic flux density in the steel with 0.12% antimony reached the maximum value, while the core loss didn’t increase obviously. However, when the antimony content in steel reached 0.22%, the magnetic properties deteriorated significantly. This is maybe that the addition of antimony in steels inhibited the development of {111} texture content and increased the intensity of Goss and {100} texture on the grain boundary.

By constructing a novel electrochemical cell, the corrosion behavior of pure zinc under the combined layer of 3 wt% sodium chloride electrolyte consisting of an open layer connected with a confined one was studied. The results show that a galvanic corrosion cell is formed once the zinc being covered by the combined layer of electrolyte, where the zinc under the open layer (named as open-Zn) plays as the cathode but the zinc under the confined layer (named as confined-Zn) as the anode, therefore the latter presents the higher corrosion rate. Furthermore, because ions transfer between the open layer and confined layer become difficult, the hydrolysis of excessive zinc ions in the confined electrolyte results the acidification of electrolyte and thus also accelerates the corrosion of confined-Zn. The critical thickness for corrosion of zinc under the combined layer is 105 μm where corrosion rate for both of the open-Zn and confined-Zn reach the maximum.

In oil-delivery pumps, impeller failure is a common cause leading to excessive vibration. This paper is aimed to analyze the fault causation of impeller failure in oil-delivery pumps by using fuzzy Petri net (FPN) theory. The longest path algorithm based on the forward reasoning was put forward and introduced into fuzzy Petri net. First, on the basis of various factors causing impeller failure, an FPN model of impeller failure in oil-delivery pumps was constructed. Then, by using the proposed algorithm, fault causation analysis of impeller failure was completed to calculate the credibility of impeller failure. Finally, the corresponding preventive measure was presented. The results indicate the key causing factor of impeller failure is mechanical impurities, and the credibility of impeller failure is 0.7342, which is consistent with the actual situation. The research finding demonstrates the flexibility and effectiveness of the FPN in fault causation analysis.

Intelligent management of bullets at shooting ranges suffers from the limitations of manual bullet counting. Based on UV electro-optical technology, we have built a bullet counter and participated in field experiments. The bullet counter is composed of two modules, UV electro-optical module and data processing and communication module. In UV electro-optical module, a ‘solar blind’ UV detector is used to detect UV radiation of bullet flames. The embedded preamplifier of UV detector and the low-pass filter increase the signal-to-noise ratio of the system greatly. In data processing and communication module, analog signal, containing bullet impulses, is converted to digital signal and counted by a timer. The results of bullet counting can be read by USB. All these functions are implemented by STM32 (STM32F103CBT6), a microcontroller based on Cortex-M3. The bullet counter has been put into use at several shooting ranges and worked well.

Wireless sensor network is a new type of wireless network. IEEE 802.15.4 / Zigbee standards with low energy consumption, low speed characteristics has been widely used in wireless sensor network. As the wireless sensor nodes are often set in complex geographical environment and had not continuous power supply, thus saving energy has been one of the main directions of research at home and abroad. Cellular automata are a mimic biological cell reproduction form of dynamical system, with a simple rule to reveal the complex global characteristics. This paper presents a kind of cellular automata and Zigbee based wireless sensor network binding mechanism, so that the wireless node according to the communication state during hibernation and job switching between states in order to achieve the purpose of energy saving. Simulations show that the mechanism can reduce the network energy consumption, improve energy utilization rate, and prolong the survival time of the node.

The extraction of characteristic parameters is extremely important front-end of the speech recognition system, accurate parameters extraction of Mongolian speech have the important meaning to its recognition technology development. This paper clarified Mel frequency cepstrum coefficients(MFCC) features and extraction method at first, then it will treated with the first-order and second-order difference, after that, combining these parameters will get a new feature parameter vector. Analyze and extract this eigenvector from Mongolian speech signal by means of MATLAB. Experimental results reveal that the more the feature parameter is, the more precise the description for static and dynamic characteristics of ear to speech is.

Based on the Palmgren-Miner linear cumulative fatigue damage theory, the blade root fatigue loads in different effective turbulence intensities were calculated and analysed. The results show that when the air density and the wind speed are constant, the blade root fatigue loads increase linearly with the effective turbulence intensity increasing, and the slopes increase linearly with the wind speed increasing. According to these results, the main source of the blade root fatigue loads under different wind conditions can be estimated to provide a theoretical basis for WTGS type selection in the special sites.

Mode analysis for wind turbine is more and more important with the large-scale direction development of wind turbines. Considering twist angle of blade, centrifugal force, weight of blade, weight of tower and nacelle, turbine inertia, traditional transfer matrix theory is amended and applied in the mode analysis of wind turbine in this paper. Applying amended transfer matrix theory, the mode analysis of a real wind turbine is made and the analysis results are compared with the calculation results from NREL Mode program. The comparison results show that amended transfer matrix theory takes wind turbine inertia into account and have higher accuracy.

Cavitation is an important factor on influencing the safety and efficiency of hydraulic machinery. So cavitation characteristics and mechanism are the work targets of many scholars. And how to reduce the risk of cavitation is also a hot issue. In this paper, geometry structure of hydrofoil is changing, with different number and angle of hole. Flow fields of hydrofoil are analyzed and compared, and then the effect of drilling angle on flow field of hydrofoil is given. This study introduces geometry optimization ideas for improving cavitation in the area of hydromachinery.

With the large-scale direction development of wind turbine, the vibrations of wind turbines, which are rigid-flexible coupled multi-body systems, can be easily excited. Control system can be improved to reduce the vibration amplitude and load levels. Fluctuation-suppression pitch control strategy has been improved in this paper. The reference input rotation speed, which is normally constant, is required to change with rotation acceleration in pitch control in this new control strategy. Theory and simulation show that Fluctuation-suppression pitch control (FSPC) strategy can improve the vibration characters of wind turbine and suppress rotation speed and power fluctuation, and it is also quite effective for gust situation

The change of mechanical torque is usually ignored in small disturbance of power systems, which means that influences of the hydro turbine and governor system (HTGS) have been ignored. The disturbance characteristics of the hydro turbine generating units including the HTGS is studied based on torque coefficients method in this paper, and calculating method and expressions of torque coefficients of the HTGS are given. The additional mechanical damping produced by the HTGS can be expressed as DtΔω, therefore, it can be merged into the damping item in the motion equation of generator, that means that its action is equivalent to modify damping coefficient D. Using a case, the analysis and calculation method are introduced, and several conclusions are given.

The paper studies the nonlinear vibrating mechanical behaviors of double-walled carbon nanotubes (DWCNTs) with the initial axial stress under the temperature field. The DWCNTs are modeled as double elastic shells coupled together through vdW interaction between inner and outer nanotubes. Based on the model, the relation between the amplitudes and the frequencies of the tubes is achieved. The results show that the initial axial stress could crucially affect the topological forms of the amplitude-frequency curve, whereas it is insensitive to the amplitude ratios in DWCNTs. Meanwhile, it is also concluded that the temperature change is significant for natural frequency, but weakly affects intertube frequency and amplitude ratios as well as amplitude-frequency curve.

Given there is a great deal of correlation among indicators in the process of computer network security risk assessment, the handling of correlation is of great significance for the effectiveness of risk assessment. In this paper, we propose a hybrid computer network security risk model based on the analytic hierarchical process and gray relational analysis theory. At fist, the weight of each indicator will be elicited by means of analytic hierarchical process. Further, gray relational analysis theory will be used for the final evaluation, which avoids subjective estimation of experts or managers of banking. Finally, the model is further demonstrated and validated via a case study, and the result implies that the assets and vulnerability may be the most important factor for network security management.

The Catalytic Wet Oxidation (CWO) method was investigated to treat phenol cleaning wastewater from chemical container which is difficult dispose with traditional biological methods. In this paper, high-efficiency catalysts were prepared, two methods were used to prepare the catalyst: impregnating, sol-gel. Effects of metal salts concentration, calcination temperature and calcination time on each catalysts performance were explored and optimal catalyst preparation condition was optimized. The results show that the optimum sol-gel condition: Cu / Mn / Ce ratio of 2:2:2, the calcination temperature is 700 °C, calcination time is 5h.; the optimum impregnating condition: Cu / Mn / Ce ratio of 2:2:2, impregnated carrier (AC) of 0.9g/L mixture, the calcination temperature is 300 °C, calcination time is 4h; the sol-gel catalyst has longer service life, the samples prepared by impregnating technique were more active than the samples prepared by sol-gel technique at given reaction conditions.

Studies have shown that the internal pressure of the spiral case could cause damage of the surrounding concrete, and the damage range and level are possible to grow with the repeated action of water hammer pressure. The security of spiral case structure may be adversely affected by damage of the surrounding concrete. In this paper, the case study of a spiral case which located in Nuozhadu hydropower station in Yunnan Province is presented. In order to analyze the damage effect of surrounding concrete under the repeated maximal water hammer pressure, a three-dimensional finite element model is established by ABAQUS software. In calculation, the contact elements are used to simulate the feature of frictional contact between steel liner and surrounding concrete, and the concrete damage plasticity constitutive model is adopted to describe the tensile characteristic of concrete. At last, according to the results of simulation, the damage range and level are investigated.

Based on the good function for 3D modeling of Pro/E software, 3D geometry modeling for the entire flow passage of HLA351 which is the Francis turbine with long and short blades was realized by means of a series of methods of drawing from inside to outside, drawing from top to bottom, drawing lines from points, drawing surfaces from lines, and finally getting body from surfaces, so as to provide a reliable foundation for the future CFD calculation and performance prediction.

To observe the effect of NR2B-siRNA mediated by hydroxyapatite nanoparticles (HA) on formalin-induced inflammatory pain of mice and the expression of NR2B in spinal cord. To preliminarily investigate the feasibility of HA as siRNA carrier to transfer NR2B-siRNA in vivo. The sequence-specific NR2B-siRNA of mice was designed and synthesized initially. Using HA as a siRNA carrier, green fluorescent protein(GFP)-siRNA as the control, 4 ug of NR2B-siRNA was administered into subarachnoid space of mice via conscious injection. On 7th day after intrathecal injection, formalin test was observed for 1 hour in each group, followed by dissection of lumbar segments of spinal cords immediately for use in immunohistochemical staining of NR2B. The results show that NR2B-siRNA not only significantly abolish the nociceptive response of mice in the tonic phase induced by formalin, but also decrease the amount of cells expressing NR2B protein in spinal cord, while GFP-siRNA mediated by HA don’t produce the same effects, which demonstrates that HA is capable of effectively transfering NR2B-siRNA via intrathecal injection, furthermore, HA/NR2B-siRNA complex can significantly reduce formalin-induced pain of mice, and specificly inhibit NR2B expression in spinal cord of mice.

The paper studies the nonlinear vibrating mechanical behaviors of double-walled carbon nanotubes (DWCNTs) with the initial axial stress under the temperature field. The DWCNTs are modeled as double elastic shells coupled together through vdW interaction between inner and outer nanotubes. Based on the model, the relation between the amplitudes and the frequencies of the tubes is achieved. The results show that the initial axial stress could crucially affect the topological forms of the amplitude-frequency curve, whereas it is insensitive to the amplitude ratios in DWCNTs. Meanwhile, it is also concluded that the temperature change is significant for natural frequency, but weakly affects intertube frequency and amplitude ratios as well as amplitude-frequency curve.

In this paper, the structural passive control which has the broad application prospect in seismic shock resistant and the wind-resistant design of civil engineering is introduced. the principle and wide application of structure passive control technology including basal isolation, energy dissipation damping and shock absorption damping in civil engineering are expounded, and the development for passive control technology development is prospected.

Traveling light is totally reflected on boundary, the evanescent wave intensity exhibits exponential decay with distance from the boundary at which the wave was formed. In this paper, we do theoretical analysis of the total reflected light phase shift and power value of the evanescent wave was “disturbed” by the other objects. A marvelous optics phenomenon is the -π/2 phase shift of reflected light.

In order to understand the rationality of the structural design for one hydropower underground house, based on reasonable selection of loading method for generator pier, and appropriate dealing with volute casing and draft tube water pressure. Take a typical underground house of anlagensektion to build the three-dimensional finite element model, and spectrum method was applied to analyze underground powerhouse anti-seismic characteristic. The seismic response characteristic of powerhouse just under seismic action and static load of normal operation jointly are investigated. The anti-seismic safety property of powerhouse is evaluated. It provides scientific basis for powerhouse dynamic design and operation control that station project.

The paper develops a special CAD system for the centrifugal fan. The system can realize the automatic selection,aerodynamic design calculation,main parts parameterized drawing and other functions of the fan. It avoids the repetition of the manual labor and enhances the working efficiency and the cartography quality. On the base of the research on the selecting method and regularity of the main parameters of a large number of existing high performance centrifugal fans, the paper provides a new method, which determines the main geometric parameters of centrifugal impeller.

The helath condition of rotor has been greatly concerned in rotating machinery. But for the lack of information, it is very difficult to judge the actual conditon. Based on the fuzzy and grey characteristics between faults and symptoms, a new method integrated with fuzzy clustering and grey relation analysis was put forward to identify the condition of rotor system. Firstly, eight features, such as average value, peak-peak value, variance value, virtual value and etc., were extracted from the vibration signal of rotor system. Then, fuzzy C-means algorithm was used to cluster forty samples into 4 clusters, meanwhile, the clustering center was acquired and regarded as standard pattern matrix. Finally, the grey relation degree was calculated between pattern to be inspected and the standard pattern matrix. Using this method, the unbalanced conditions of rotor system was precisely identified, which shows that the integrated method is valid and practicable.

This paper investigates the flexural strength and ductility of hybrid high performance steel (HPS) I-beams. Three simple supported I-beams were tested to study the bending behavior of hybrid beams with Q&T HPS 485W in flanges and Q235 in webs. Experimentally verified nonlinear finite element modeling techniques were then employed in a parametric study including the influence of cross section compactness and material match in hybrid design on rotation capacity of beams. It is observed that the compactness of flange and web have a major influence on the rotation capacity of flexural beam. As a result, appropriate compactness criteria are suggested for use in the design of HPS 485W hybrid beams employing compact webs made from lower strength steels.

Colloid mill or high-speed shearing mechanical is used in traditional preparation technology of SBS modified asphalt for the dispersion of SBS in matrix asphalt, which leads to the high equipment cost in production of SBS modified asphalt. The fractions oil of FCC slurry oil distillation with a high content of aromatics is a good swelling agent of SBS. The FCC distillation residual (FR) with high softening point can resolve the problem that penetration increased when the addition of swelling agent increased. SBS is pre-swelled by the heavier fractions from FCC slurry oil, and then it will be dispersed in the vacuum residuum (VR) by simple mechanical stirring to prepare SBS modified asphalt due to the perfect swelling effects in this work. The influences of different materials, distillation yield and ratio of FR to VR on the performance of SBS modified asphalt have been investigated. Fluorescence microscopy was applied to observe the different disperse images of SBS modified asphalt prepared by simple mechanical stirring and high speed shearing. The results indicated that the novel method can be used to prepare SBS modified asphalt with good performance and storage stability.

CNTs were treated with hydrazine hydrate and diethylenetriamine, respectively. Scanning electron spectroscopy (SEM) observation showed that the doped CNTs kept the length/diameter ratio of pristine CNTs. X-ray photoelectron spectroscopy (XPS) characterized that nitrogen can be doped to CNTs. XPS analysis further indicated that C/N atomic ratio of CNTs treated by hydrazine hydrate is 95/2, four times of CNTs treated by diethylenetriamine, which is 96/0.5. The hydrophilicity for N-doped CNTs (N-CNTs) is much improved and enhanced by increasing N proportion. As electrode material of supercapacitor, nitrogen functional groups contribute pseudo-Faradic capacitance, but its cyclic performance still need to be improved. Thanks to the good hydrophilicity for N-CNTs that improves the wettability of CNTs for electrolyte; the specific capacitance of N-CNTs is still slightly higher than pristine CNTs after cycling.

Based on the characteristics of SBS modified asphalt (SBSMA) and crumb rubber modified asphalt (CRMA), crumb rubber and SBS composites modified asphalt (CR/SBSCMA) technology is proposed combine the advantages of crumb rubber and SBS. The preparation technology and production process factors have been discussed in this work. Moreover, the performance comparison results of three modified asphalts confirms that CR/SBSCMA could achieve good high and low temperature performance with low content of SBS and crumb rubber. Furthermore, the separation behavior of CR/SBSCMA has been analyzed, the experimental results indicate that the separation behavior of CR/SBSCMA is caused by the sinkage of rubber particles as well as CRMA. However, the softening point difference of CR/SBSCMA after separation test is smaller greatly than CRMA due to the prevention of SBS particles.

This paper gives a brief introduction of the developmental history of high performance steel (HPS) all over the world. Emphasis of current paper is on the characteristic studies of HPS 485W, which is new structural weathered steel produced by Wuyang Steel Iron Company using quenching and tempering (Q&T) in China. To obtain the strength and ductility of HPS 485W, the tensile coupons were machined from each 8mm, 10mm, 12mm and 14mm thick plate. Based on the static tensile tests in room temperature, major of material mechanical characters were obtained, such as yield strength, ultimate strength, elastic modulus and so forth. Besides, to examine plate toughness, 30 Charpy V-Notch (CVN) specimens from 12mm thick HPS 485W plate were tested from 20 oC to -196 oC . Compared with conventional bridge steels, the CVN test results show that the fracture toughness of HPS 485W is much higher, and the brittle-ductile transition of HPS occurs at a much lower temperature. A set of 9 single-edge bend specimens were took from 20mm and 30mm thick HPS 485W separately for ductility fracture toughness test. The calculated JIC value is 415.8 kJ/m2 for 18mm thick specimen and 507.79 kJ/m2 for 28mm thick specimen, which shows ideal ductility of HPS 485W.

Effects of silicon concentrations in Ni-Cr-based alloys on the formation of oxide scales were examined in reduced atmosphere. The morphology and oxide scale were compared based on the Si content. The formation and growth kinetics of the oxide scale are rather sensitive to the alloy microstructures and their corresponding Si contents. Oxide ridges formed on the eutectic structure preferentially, while a thinner and homogeneous oxide scale grew from the austenite matrix. The thicknesses of the oxide ridges and the oxide layer on the austenite matrix are dependent of their corresponding Si contents. The ridge-like feature indicates that the austenite/carbide phase boundaries offer fast diffusion paths for metal atom outward diffusion. The formation of SiO2 sub-layer at the oxide scale/metal interface can act as an effective diffusion barrier for atom outward diffusion.

In this paper, we use electromagnetic simulation software HFSS to investigate the distribution of electromagnetic field of microwave sintering cavity, and establish a simulation model for the TE103 single mode cavity. We then obtain the optimal condition for the distribution of electromagnetic field by capturing the contour of distribution of electrical field of cavity through simulation. Our research shows that electromagnetic simulation software HFSS can use color to effectively demonstrate the intensity distribution of electromagnetic field of internal space and various cross-sections within the microwave sintering cavity, which provides a novel method for improving and applying new ways to compute and predict the key features of field distribution. The simulation results by HFSS can guide the practical microwave sintering techniques as well as the design and improvement of the sintering cavity.

Atract: Taking the underground powerhouse in a large pumping station as an example, to establish the geometric model of the underground powerhouse structure, and finite element division, analysis of the natural vibration characteristics of the structure, using the method of harmonic response analysis, calculation and analysis to the vibration response of the structure under different conditions. Provide a theoretical basis for the safety evaluation of building structure.