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In this paper, the comprehensive property of shielding fabrics was analyzed by the mathematic method-grey cluster analysis. Eight samples of shielding fabrics were selected as research objects in the experiment. The electromagnetic shielding effectiveness in different frequencies and wearing comfort, including tensile and bending property, abrasive resistance, permeability and color fastness were measured and then analyzed. Grey cluster analysis was carried out to evaluate the comprehensive property of the chosen samples by eight clustering objects and nine clustering indexes. In the process of data operation, MATLAB7.0 was used to calculate experimental results due to its high efficiency and accuracy. According to cluster analysis results, the eight samples were divided into three gray classes, namely, 2#, 5# belonging to “first-rate”, 4# and 7# belonging to “medium” and 1#, 3#, 6#,8# belonging to “low-rate”.

This paper presents a new vacuum preloading technology in which hydraulic fill is used for sealing while the sand cushion is not necessary. Thus this technology is applicable for projects with scarcity of sand resources.This paper dedicates the characteristics of this technology, reinforcement mechanism, applicable scope, construction technique, reinforcing effect and prospects, in an effort to provide guidance and promote the application of this technology.

The aims of the present work were simulating actual environmental pollution to select and compare the bacterial communities under different environmental stresses such as phenanthrene and pyrene. Two bacterial consortia named as Phe consortium and Pyr consortium were enriched from activated sludge obtained from a wastewater treatment plant. The PCR-DGGE analysis showed that the original active sludge harbored abundantly diverse PAH-degrading bacteria at first, then under different environmental pressures the consortium species tended to be concentrated and had species structure differences. In addition, the abilities of the two bacterial consortia to remediate a mixture of 4 PAHs (50 mg Kg-1 each) in soil were studied. Of the 4 PAHs, greater than 80% of the fluorene and phenanthrene in soil were removed by the Phe consortium in just 7-days respectively; whereas the Pyr-consortium could degrade over 60% of anthracene and pyrene.

In this paper, the properties of TiN, AlTiN, CrN and CrAlN coatings were studied and compared, include physical and mechanical properties and micro morphology. The result showed with addition of Al, ternary AlTiN and CrAlN coatings showed dense structure and high hardness compared with TiN and CrN coatings. Adhesion strength of the Cr-based coatings was obviously higher than Ti-based coatings, but the roughness of Cr-based coatings was less than Ti-based coatings. Concerning microstructures of the coating, better ductile and dense are the remarkable character of the AlTiN and CrAlN coatings because of the disappearation of the “drop-lets” and columnar crystals.

In HongKong-Zhuhai-Macao bridge project, about 4.8 kilometers stone bed underwater should be compacted to make it smooth and remove the excess settlement. Vibrating compaction method would be used to tamp the stone layer with no dead angle in a short construction period. This paper theoretical studied on vibrating compaction technology of scattering-filling rubble stone layer. Vibrating compaction system and stone layer were simplified to a mechanical model and the vibration equation was established. According to an interpolation table, a fitting formula of equivalent damping was given. Through rigorous mathematical derivation, this paper gave mathematical expressions of the vibration displacement, the vibration velocity and compaction work on stone layer. Both compaction work on land and compaction work underwater could be calculated by these mathematical expressions. Lastly, through a set of field test parameters, comparative analysis between compaction work on land and compaction work underwater was carried out. The result shows that the weakening effect of water on compaction work is poor.

Because of the high heterogeneity, late water flooding and irregular well network, the distribution law of residual oil reserve in Chang 6 reservoir becomes much complicated. Combining the geology with dynamics of the reservoir, volumetric and formation coefficient methods are adapted to calculated the residual reserves, and then the distribution laws and controlling factors are analyzed. The results indicate that: there are still large amounts of residual reserve in main layer Chang 622; the residual reserve can be classified into three kinds, Class I and class II are distributed concentrative in main layer; the controlling factors include property, sedimentary facies, heterogeneity, well network controlling and geological structure and so on. Finally, according to the distribution laws and controlling factors, targeted measures are proposed. The studying results provide well foundations for improving recovery of residual oil reserves and the total recovery of the reservoir.

To solve the difficulty of traditional video monitoring system in system upgrade and expansion, an solution of embedded video monitoring system based on DaVinci technology was put forward in this paper. By building the monitoring platform by DM6437 and DSP/BIOS in the solution, TVP5151 was used for receiving video signal in PAL/NTSC formats, and an JPEG Baseline Profile Encoder was integrated for video encoding, and the 10/100M Ethernet transmission function was realized based on NDK. Finally, the system is tested and the result shows that the system can capture and transmit D1 format signal in 25f/s and met the real-time requirement. At the same time, the system is easy to use and expand with a bright application prospect.

With the development of global economy, resource shortage and environmental pollution is increasingly serious. Household electrical appliance industry is facing great pressure. The traditional design pattern already could not meet the developmental needs. Based on the whole of product life cycle, this paper studies the household electrical appliances green design methods, mainly including: green material selection design, green structure optimization design, green recycling design, from design source to improve the household electrical appliances environmental friendliness and market competitiveness.

In order to calculate the efficiency of hydrocarbon expulsion by material balance method, we analyzed and corrected the geochemical parameters of five source rock samples. The hydrocarbon generation kinetic parameters of these samples were calibrated by the model of limited parallel first order reaction, and then these were extrapolated with the burial history and thermal history, then we got the hydrocarbon-generating section. Combined with the corrected geochemical parameters calculate the generating hydrocarbon amounts and expulsive hydrocarbon amounts. The result shows that: expulsion efficiency of hydrocarbon source rocks in this research were mainly between 59.1% -91.8%. It is determined by maturity (Ro), type of organic matter and pyrolysis parameters S1、S2.

Zirconium hydrogen phosphate / sulfonated poly (arylyene ether) s composite membranes has been prepared and evaluated by the unit cell test for direct methanol fuel cell (DMFC) applications. The comparison between the performances of zirconium hydrogen phosphate/ sulfonated poly (arylyene ether) s composite membranes and Nafion 115 shows that the unit cell performance with composite membrane was superior to that of Nafion, which makes zirconium hydrogen phosphate/ sulfonated poly (arylyene ether) s composite membrane a potential candidate for direct methanol fuel cells.

The simulation of glow discharge in N2 in a needle-plane configuration with PIC/MCC method is presented. In the discharge channel the electric field driven by space charges is solved by PIC method, and various collisions between particles are described with MCC method. The electric field intensity, the electric potential and the net charge distribution in the discharge area are obtained. The numerical results are consistent with the corresponding features of glow discharge. This work can provide references to further study of glow discharge.

In winter, it is very important to get rid of the ice and accumulated snow which are covered in the road so that it can reduce a series of badly accident. Therefore, a variety of road deicing methods are listed in this paper. The advantages and disadvantages of road deicing methods are analyzed. The article enumerates some inductions to several road deicing devices which are used in the cold areas of our country. The paper gives some reference for road deicing devices research.

Transportation always plays a significant role in national economy, of which roads and bridges are the most important facilities. The conditions of the road surface have an overwhelming influence on the traffic flow and road safety, especially in winter and the regions with frequent snowfall, thus closely affected the development of the urbanization and economic prosperity. In view of this, this article has analyzed the characteristics of the existed de-icing technologies, coming up with a new synthetically de-icing method which consists of thermal water-jet cutting with mechanical milling technology. These two kinds of de-icing methods are combined as a set of multi-functional system, in which the thermal water-jet cuts the ice layer into separated sections, and the mechanical milling unit then easily removes the remaining sections out of the road. To obtain the prime influential factors in this new de-icing device, repeated indoor experiments were conducted, which provides some theoretical references to further advance the de-icing efficiency and make structural optimization.

With the improvement of living standards, people want to have a comfortable, convenient, safe working and living environment. In this context, the traditional architectural forms has been unable to meet the basic needs of the people. Therefore, in recent years, the intelligent building has been rapid development in our country.In the intelligent building, electrical equipment occupies a very important position. For reliability and safety considerations, the power requirements of various equipment in intelligent building is very high.This paper designs a kind of intelligent building power monitoring system based on Internet of things. This system treating embedded hardware as the core, basing on ZigBee wireless communication technology for signal transmission, using GPRS communication technology to remote monitoring system, achieved the control of a variety of equipment in the power system in the intelligent building of local . The test result shows that this system runs stably, and has practical application value.

This paper focuses on the study on the installation angle of the adjustable movable blade axial flow fan.At first, the airfoil and the corresponding series of fan is selected, and detailed calculation of the blade section is performed to obtain the chord length and the thickness of the fan airfoil at different circumferential surfaces, as well as the coordinate value of each section. Then, a three-dimensional solid modeling of the fan with different installation angles in Pro/E is used for mesh generation and boundary conditions arrangement in Gambit. Finally, an analogue simulation is carried out in fluent to analyze the velocity of the blade, the backpressure and turbulence generated by the airflow on the blade.

To investigate how the conventional speeds to affect passenger cars ride comfort under a kind of road surface profiles, in multibody dynamics software (ADAMS/Car), a vehicle model was built based on the characteristic parameters of a passenger car. According to the relevant test regulations of ride comfort, the building methods of road surface profiles were discussed. Furthermore, a dynamics simulation analysis of the car was realized by ADAMS/Car and the acceleration-time histories of the seat surfaces X/Y/Z-axis under three conventional driving-speeds were acquired. A special MATLAB program was compiled to calculate the total weighted Root Mean Square (RMS) value by calling the above histories. According to the GB/T 4970-1996, a road test of a passenger car was carried out in the random road surface which equivalent to B level. The car was driven to get the values of total weighted acceleration RMS under three conventional driving-speeds. By comparing the road test result with simulation, the result indicated that the changing trend of total weighted RMS value is consistent as the driving-speed changes, and the ride comfort will decrease when the driving-speed increase. At the same time, it shows that the consistency of the simulation and road test is better.

Order-preserving encryption (OPE) scheme is a deterministic symmetric encryption scheme whose encryption algorithm produces ciphertexts that preserves numerical ordering of the plaintexts. The cryptographic study of OPE was initiated by Boldyreva, Chenette, Lee, and ONeill [1]. They proposed an OPE scheme based on a sampling algorithm for the negative hypergeometric distribution (NHGD). In this paper, we present the security analysis of NHGD-based OPE and the proof procedure of efficiency.

By choosing even universal Lyapunov’s function, we obtain sufficient condition of independent stability and exponential stability of delayed system . By choosing a set of suitable parameters, we can reduce the conservation of condition. As a result, this method provides a new way to ameliorate stability in robustness bounds and robustness control for uncertain system with delayed state. Analyze oil-water separation process of control system in the unite station. Obtain variation relevancy chart with oil-water separation process. Clear classify the relation among variation.

This paper introduces the role of axial flow fan with adjustable movable vane, aiming at complicated structure, difficult regulation and hydraulic device leakage of hydraulic movable vane regulation device, designs a new kind of movable vane regulation system-electronically controlled movable vane regulation system, describes the composition and working principle of electronically controlled movable vane regulation system, and emphasizes on structure features of control system, reducing mechanism and impeller assembly.

This paper first analyzed the background of the construction of low carbon city and pointed out the advantages and disadvantages of the low carbon construction of Qingdao. Finally, this paper proposed some practical countermeasures and suggestions for the development of low carbon economy in Qingdao.

In this paper, a model of energy-environment-economic model based on dynamic CGE model is constructed after the linkage of dynamic CGE model and energy technology model, the choices of policy of energy conservation and carbon reduction to deal with the change of climate are analysed. Besides the improvement of technology of energy, if carbon taxation is employed, the goal to reduce its carbon intensity by 40% by 2020 compared with 2005 need to levy a tax of 60yuan per tonne, the simulations of this tax to carbon reduction, economic and income of residents are analysed under different circumstances, the results shows that there is a great impact on income of residents and reduction-intensive industries with a higher tax burden level.

The fabrication process and fracture characterization of 35 and 65 vol% SiCp particulate-reinforced Al matrix (SiCp/Al) composites have been investigated. SiCp composites having different volume fractions of the n-SiCp were synthesized via by pressureless-infiltration at near-net-shape route and were uniaxially tested at room temperature. The SiC particles were mixed with silicasol as an inorganic binder in distilled water. The mixtures were consolidated in a mold by pressing and dried in two step process, followed by calcination at 1000 °C. The SiCp/Al composites were fabricated by the infiltration of Al melt into SiC performs. The experimental results show that volume fraction of reinforced particles in SiCp/Al composites had a significant influenec on fracture section surface characterization in tensile tests. Composite with 45 vol% SiCp, fracture was firstly happen in Al matrix, shallow dimples and intergranular fractures were seen in all the fractographs. With increasing of vol% SiCp, fracture was more brittle in appearance in the composites and the fracture surfaces were flat and less plastic deformations.

The distribution of poles affects the property of the automatic control system. The paper studies how the poles in the left half of s-plane affect the transient performance of the system by Matlab tools and analyzes the reasons for these effects. Discuss the different effects of the closed-loop poles and the open-loop poles to the same automatic control system.

Brittleness source identification is the work of finding every brittle source. The key of analysis of the brittleness of system is to build the brittle model. The chart theory can describe the direction and weigh of the brittle spread model. In this paper, bring forward the method and step of building the brittle model based on the chart theory, build a model of 7 nodes electric power system and analyze it and then obtain the hierarchy electric power system brittle model and the brittle source, and at last verify this method is valid to network system.

Research on the synthesis of BrOnsted acidic ionic liquid by the method of solvent, the pyrolysis bio-fuel with cornus wisoniana oil drop acid esterification reaction, the catalyst dosage, reaction time and reaction temperature on the effects of the acid dropping and in the best optimization under the condition of the stability of the catalyst were investigated. The experimental results show that [BSPHSO4 with high catalytic activity, optimization of process conditions as follows: 1.2% of catalyst, reaction temperature 75 °C, reaction time of 70 min, acid value reduced to 2.0 mg KOH/g. By optimizing the cycle experiment, the stability of the catalyst performance is good, the catalytic activity is relatively stable.

In this study, the trench oil was processed by the technology of polyol pre-esterification and the bio-diesel was prepared using basic ionic liquid 1-methyl-3-butyl-imidazole hydroxide as a catalyst. The amount of ionic liquids, alcohol and oil molar ratio, reaction temperature and reaction time were investigated on the transesterification reaction. The results showed that the bio-diesel prepared conditions by trench oil are as follows: alcohol and oil molar ratio of 8:1, reaction temperature 70°C, reaction time 110min and the amount of catalyst for the quality of raw materials 3.0% oil. Under these conditions, fatty acid methyl ester was 95.7% conversion rate.

Uterus didelphys associated with unilateral imperforate vagina is a rare congenital anomaly. Clinically the patients present with nonspecific symptoms, an accurate and whenever possible noninvasive diagnosis is of utmost importance to permit corrective treatment and as little mutilation as possible, and to assure the future fertility of the patient [1, 2]. We report 3 cases and discuss the use of Magnetic resonance imaging (MRI), as a very reliable diagnostic tool in such cases. By characters of MRI, the congenital malformation was detected for these cases and appropriate treatment was implemented.

Erasure codes received extensive attention in the cloud storage system because of its effective on saving storage space,However, due to the high recovery-overhead of erasure code, its application has been limited in these storage systems.For these problems,in this paper,we presents A multi-server Erasure code algorithm based on the degree of restriction to reduce the recovery-overhead from the restriction of date and parity's degree,and enhance the system performance to a certain extent ,ensure the reliability of the data of the cloud storage environment.

The paper reports the tribological properties of the CrAlN coating tools at different speeds and loads. The coating was deposited on cemented carbide by cathodic arc physical vapour deposition technique. Ball-on-disc wear tests were performed on the CETR UMT-2 test system against SiC balls. The coating character and test results were obtained through SEM, XRD and Wyko surface profilometer. The results are as follows: The value of friction of coefficients decreased and depth of wear tracks became sallower as speeds increased and the coating presented adhesion phenomenon under low load. CrAlN coating showed excellent anti-wear properties at high speed and low load, and was more suitable for these similar working conditions.

To solve the unknown faults diagnosis online for analog circuit, a novel faults diagnosis strategy based on improved kernel fuzzy c-means (IKFCM) is proposed. simultaneously, the high-performance recognition tree structure of the improved kernel fuzzy c-means itself can decrease the train sample and eliminate wild value, the training speed and precision of classifier can be done well in this way. The realizing of precision fault diagnosis, firstly, via confirming exact class centers from the data of known faults, and then the mean value can be obtained relying on the faults data of each class, meanwhile, setting this mean values as the thresholds for judging faults and each data point is issued with a class label. During the whole faults diagnosis, each detection data will be compared with the thresholds, the high similarity detection data will be fall into the known faults classes while the low similarity detection data will be labeled as unknown faults. Simulation proved the well performance effectively of the proposed IKFCM method .

An axial compression test has been done on 12 short columns, ribbed and spiral stirrup short column filled with recycled demolished concrete lump to study the axial compression variable characteristics and ultimate bearing capacity of thin-wall T-shaped steel tube column filled with recycled demolished concrete lump. The load displacement curve has been analyzed, ultimate bearing capacity of standard formula has been compared and the reliability of finite element numerical simulation and been discussed. The result shown that the form of steel tube embedded with structural members has more effectively increased the tensility, delayed bending occurrence, enhanced the effect of restraint of core concrete and increased the ultimate bearing capacity than that the form of plain section form. The ultimate bearing capacity of ribbed form has been increased by 16.76% than non-ribbed form，and the ultimate bearing capacity of spiral stirrup form has been increased by 11.98 % than non-spiral stirrup form. The finite element simulation and the test result was identical properly.

Sodium dodecyl sulfate/Pt composites and sodium dodecyl sulfate/Pd composites have been synthesized and used to modify the surface of Nafion membrane. Modified Nafion membranes have been characterized by Fourier transform infrared spectroscopy (FTIR). The properties of the modified membranes, in terms of their conductivity and the performance of the membrane electrode assembly (MEA) in the direct methanol fuel cells (DMFCs), have been analyzed and compared with those of the bare Nafion. It is found that the DMFC performance of the membranes modified by two kinds of catalytic materials are better than that of the bare Nafion when operated with 2.0 M methanol. The good conductivity and high cell performance makes the modified Nafion interesting candidates for DMFCs applications.

Based on a thorough research of Shizhong County in Fujian Province, some developing problems have been detected, such as shortage of land, backward transportation, negligence of historical building protection and unused tourism resources. The author puts forwards the planning scheme of the historic town after the study of master plan of Shizhong County, conservation planning of historic town, and tourism develop plan. For historic towns, a coordinated planning pattern is needed. This new pattern should take the master plan as the guideline, and the historical culture protection plan and tourist development plan as strategies. With the unfolding of the three plans, a harmonious development will be achieved.

Hierarchical ZrO2 nanorods have recently received considerable attention due to their special physical and chemical properties. However, traditional preparation methods are involved in expensive equipment, complicated process and high production cost. Here we report a simple hydrothermal approach to prepare hierarchical ZrO2 nanorod. The results show that as-synthesized products are composed of many nanorods with 80~150 nm in diameter and 15~20 μm in length. After annealing, the final product was involved into hierarchical monoclinic ZrO2 (m-ZrO2) nanorods, namely, the big nanorod was made up of many small nanorods with 20~30 nm in diameter and 300~500 nm in length. The possible formation mechanism was proposed based on a series of chemical reactions and the natural properties of zirconium.

Tungsten trioxide (WO3-x) with different morphologies was synthesized by hydrothermal method. Using a pair of Pt electrodes and Al2O3 ceramics tube as a substrate, NO2 sensing properties of the WO3 products were measured at different working temperatures. And the high sensing properties at low working temperature were also investigated. The results showed that the sensitivity of WO3 product is strongly dependent on morphology and structure. The parallel circuit mode also plays an important role in the NO2 sensing characteristics. The low working temperature can be attributed to the competitive reaction between O2 and NO2 gas. The parallel mode may increase the lifetime of sensor.

In this paper, based on the parameters of cumulative residual strain(CRS), the effects of different contents of Mg and Si elements in Al matrix on the dimensional stability of SiCp/Al composites was investigated and analyzed in the temperature interval of 25～400°C. Results show that，with the increasing of Si content in Al matrix, the CRS fluctuates only in a small range of strain, adding Si in Al matrix is beneficial to the dimensional stability of the composites, which can be improved through pre-thermal cycling; with the increasing of Mg content in Al matrix, the absolute value of negative CRS of the composites becomes smaller at the beginning and then turns positive, adding Mg in Al matrix causes the composites expand after several thermal cycling, it is not good to the dimensional stability of the composites and is quite impossible to be improved by pre-thermal cycling. Besides, the CRS in thermal cycling is mainly caused by the plastic relaxation, which results in the irreversible dimensional variation of about 10-5~10-4.

In the case of multiple loading conditions, a moving blade adjustable axial flow fan structure parameters are optimized by ANSYS. It is to achieve greater efficiency and less noise for the optimization goal. For different conditions, establish efficiency, noise comprehensive objective function using weighted coefficient method. Select impeller diameter, the wheel hub ratio, leaf number, lift coefficient, speed as design variables, Choose blade installation Angle, the wheel hub place dynamic load coefficient, cascade consistency, allowable safety coefficient as optimization of the state variables. Design variables contain continuous variables and discrete variable. Through the optimization method, we get the optimal structure parameters finally. And at the same time get the corresponding optimal blade installation Angle,under different working conditions.

High-quality β-Ga2O3 films andβ-Ga2O3 /ZnO/β-Ga2O3 nano composite thin films were fabricated on the sapphire substrates in the high vacuum atmosphere by laser molecular beam epitaxy (LMBE). The lattice structure and optical properties of these films were characterized.With the increase of the sputtering time of ZnO target ,Photoluminescence spectrums and Raman spectrums of the β-Ga2O3 /ZnO/β-Ga2O3 nano composite films were shifted regularly . When the ZnO target was sputtered 30min , the stronggest peak of Raman spectrum was appeared at 267nm . Besides,the composition ofβ-Ga2O3 /ZnO/β-Ga2O3 nano composite film was described .

On the base of analyzing the parametric design model of the screw feeder with variable diameter and screw pitches, a parametric design model of screw shaft was given in this paper. By choosing biomass material in a pocket between adjacent flights as the study object, the force between bulk material and five contact surfaces were analyzed during the conveying process, and a mechanical model for biomass screw feeders was built up. Meanwhile, a theoretical method to calculate torque of screw shaft with variable diameter and screw pitch was provided. The theoretical method could be also used in calculating torque for screw shaft with unchangeable pitch and diameter.

To indentify the influence of human activities on groundwater chemistry, fifteen groundwater samples, from the mostly exploited aquifers, were collected at Tanghai County. Considering the multivariable statistical method is reliable to study the anthropogenic process affecting groundwater composition especially in the early stage, 10 measured hydrochemical variables were used in factor analysis and hierarchical cluster analysis. Factor 1 included EC, TDS, Cl-, and K+ is interpreted as relating to groundwater salinization. Factor 2 and factor 3 is mostly influenced by the water-rock interactions during the flow path and fertile contamination, respectively. Meanwhile, the Q-mode classification result reveals that the cluster 1 having high factor 1 scores also is related to the over-pumping of groundwater, in accordance with the factor analysis result. Generally, to protect freshwater resources and suitable development of this study, some related measures should be mitigated to limit groundwater mining.

From the perspective of the Central Plains Agglomeration for a representation, comprehensive evaluation on urbanization level of all cities in Central Plain Agglomeration was carried out by using gray relation analysis, receive the ranking about urbanization level of all cities in Central Plains Agglomeration, find out the weakness and take measures for them.

A locomotive-type turbocharger compressor with 24 blades under combined centrifugal and interference-fit loading was considered in the numerical analysis. The solution of elastoplastic frictional contact problems belongs to the unspecified boundary problems where the interaction between two kinds of nonlinearities should occur. To save the time cost in the numerical computation, multi-substructure technique was adopted in the structural modeling. The effect of fit tolerance, wall thickness of shaft sleeve and rotational speed on the contact stress was discussed in detail in the numerical computation. To decrease the difficulty of the assembling process and make sure the safety of the working state, the amount of interference between the shaft sleeve and shaft by press-fitting should be controlled strictly to avoid the rapid increase of the contact stress. The numerical results show the high accuracy and good convergence of the algorithm presented here. The study play a referenced role in deciding the proper fit tolerance and improving design and manufacturing technology of compressor impellers.

This article mainly expounds that deepening of teaching reform in higher education and improvement of personnel training quality are important initiatives to strengthen the quality of higher education connotation construction, to improve students' practical and innovative ability, and to satisfy people in the new period. By being effectively consistent with social needs, mechanical major is more closely combined with mechanical engineering characteristics which meet the diverse demand of engineering talents. Cultivating project suitable to diversification of innovation talents is revised. Curriculum group and practical teaching system of creation and execution in parallel are established. We adhere to the people-centered notion and set ability training as the core, quality as the goal, the accumulation of knowledge as the basis to enhance the innovative ability of college students of mechanical engineering steadily.

In order to establish the three-dimensional model of the crankshaft piston group, the application of characteristic modeling method was proposed directly through the designer to extract features from the BULL operations, and finally form a part model of the design and definition. Analysis of the expression of the crankshaft features and characteristics of the link, use Pro-E to build a diesel engine crankshaft and the piston rod group of feature modeling. a new three-dimensional assembly drawings was built. It provide a new design ideas for reserachers.

Poly (vinyl chloride) (PVC)/halloysite nanotubes (HNTs) nanocomposites had been prepared by melt blending. The heat distortion temperature (HDT) and vicat softening temperature (VST) of nanocomposites increased with increasing HNTs feed content. Cone calorimetry was used to measure the smoke evolution and fire properties. The addition of HNTs leaded to a remarkable reduction in the smoke production rate, the total smoke production and the peak heat release rate.

In this paper, the effect of the adjustable permanent magnetic field with the maximum magnetic flux density as 4100mT on the calcium carbonate(CaCO3) precipitation process was investigated from hard water in the absence and in the presence of foreign ions Al3+、Fe2+、Mg2+、SO42+. By changing the strength of the magnetic field, the fouling resistance efficiency, the total CaCO3precipitation and precipitation in the bulk solution were determined by measurement of the mass of CaCO3precipitation, and the polymorph composition of CaCO3precipitated in bulk solution and particle size fouling on the loading slice was determined by XRD and electron microscope. The effect of MF on the precipitation process of CaCO3was tested by degassifying dissolved CO2in calcocarbonic pure water containing foreign ions. The results showed that magnetic water treatment increased the total precipitation and favored the precipitation in bulk solution instead of precipitating on the walls regardless the presence of foreign ions. The effect is intensifying with the strengthening of the magnetic flux indendity. The Magnetic field (MF) did not affect the polymorph composition of CaCO3in the absence of foreign ions. While in the presence of foreign ions, the precipitation and structure of precipitated CaCO3were significantly affected. The MF favored the precipitation of aragonite and inhibited the formation of calcitein the presence of Mg2+and SO42-. In the case of Al3+and Fe2+, the precipitation of aragonite is favored, calcite and vaterite is inhibited. The MF influenced CaCO3precipitation process by influencing the hydration process of the ions in the solution and changing the dehydration process of hydrated CaCO3as the precursor of crystal nuclei for the magnetic field change the structure of water cluster. The reason that foreign ions can change the polymorph composition of CaCO3is probably owing to its hydration and dehydration.

ZL101 Al alloy reinforced with 55% silicon carbide particulate metal-matrix SiCp/Al composite has been fabricated by pressureless-infiltration. The microstructure characterization of composite has been studied by optical microscope (OM), scanning electron microscope (SEM), X-ray spectroscopy (EDX), respectively. The results show that the SiCp are uniformly distributed in Al alloy matrix, however, there are some casting defects such as shrinkage and gas porosities in the matrix. When Mg was added into the composite, it can improve wettability property of between Al matrixes and strengthen particle SiCp and decrease micro-defects such as gas porosities, the Microstructure of SiCp/Al composite prepared was compact and uniform. The SiCp particles evenly distributed in the matrix and without significant partial segregation phenomenon. It improves the whole performance of the composites.

Pulse image detecting device was applied to acquire radial dynamic pulse images. In this paper, we improved the probe structure of the pulse image detecting device with new film material. Four kinds of different thickness films, the different pulse-taking pressures and the different sealed chamber pressures were used to determine the optimum film. For different subjects, the pulse amplitude was extracted with the different pulse-taking pressures and different sealed cavity pressures. The experiment results had shown that the best pulse amplitude could be obtained with the film thickness for 0.504 mm, pulse-taking pressure for 3 N and the sealed cavity pressure for 120KPa. This work provided an important theoretical basis for the parameter choice of the pulse image detection device.

The paper make the service life of relieving formed milling cutter as the optimization objective, proceed the simulation study on the mechanical degree of cutter, cutting data. The concrete method is that the orthogonal milling model is established to simulate the simulation milling process, some basic parameters which are obtained in the machining process are analyzed and discussed. The results indicate that the finite element simulation of the metal cutting processing can analyze quantitatively some physical properties, such as the cutting force, stress, strain and so on, the traditional way of qualitative analysis is changed. The state of machining is in favour of grasping in the theory, the theory and technology are provided to establish the proper processing technology strategy.

The engine model with 4 cylinders is built by SolidWorks, the kinematics and dynamics simulations of the engine virtual prototype are done by COSMOSMotion, the results of kinematics simulation are checked, there are very small errors between the simulation results and the calculation results according to formulas. The mainly results of dynamics simulation are given. The simulation result consists with the parameters of the engine.