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Transmission casing fatigue fracture is one of the most serious failure of the transmission system in the form of tracked vehicles. This article through the analysis of materials and structural stress analysis of a typical fracture failure mechanism of the tracked vehicle transmission cabinet. And in obtaining the stress on the basis of load spectrum its fatigue life was calculated. The results show that in the structure of the stress concentration and cabinet material number ZL101 cast aluminum defects such as inclusions, porosity are the main cause of fatigue crack initiation and propagation.

A simplified model of self-balance screen was constructed by using SolidWorks, and then imported into the Simulation to analysis its structure and modal. The stress distribution, deformation and structural natural frequency, mode shapes under static loads of the self-balance vibrating screen were calculated to provide theoretical basis for the following analysis of the dynamic characteristics and structure optimization design of vibrating screen.

Further development of SolidWorks with VB is carried out in this paper. Program and dimension driving methods are utilized for parametric design to realize the automatic generation of three dimension component and engineering drawing in SolidWorks. Intelligent generation of drawing is achieved by adjusting the view scale of engineering drawing, generating view size and cutaway view in order to improve the design efficiency and quality.

TiO2nanotubes were prepared via a hydrothermal route. CeO2nanoparticles with diameters around 5nm were loaded onto the surface of TiO2nanotubes via a deposition approach followed by a calcination process. Transmission electron microscopy (TEM), X-ray diffraction (XRD), and UV-vis diffuse reflectance spectroscopy (UV-vis) were applied for the characterization of the as-prepared CeO2/TiO2nanotubes composites. The results show that CeO2particles are highly dispersed on the surface of TiO2nanotubes. The TiO2 nanotubes are modified to response to the visible light due to the combination with CeO2. The CeO2/TiO2nanotubes composites with a CeO2/TiO2atomic ratio of 2.5% show a further improvement on the photocatalytic activity for degradation of Rhodamine B in water. The presence of CeO2improves the light absorption of TiO2nanotubes and inhibits the electron-hole recombination.

Many mathematical models can be used to optimize the fermentation process, and predict the harvest of products, but most of them only applied in the biomass factor, not the activity of enzymes, especially inducing enzyme such as α-galactosidase. In this study, Pediococcus acidilactici XS1B was incubated and measured by two periods: 48h with interval of 2h, 9d with interval of 1d. After analyze data of active bacteria amounts, biomass, catalyst activity, 2 pairs correlation were established: the active bacteria amounts with biomass increasing rate is 0.461, the biomass and catalyst activity is 0.935. With this correlation, the models used to measure biomass can also fit to α-galactosidase activity.

Thermogravimetric curves of micro nanometer iron powder’s combustion were studied in different heating rates that were 10K/min, 20 K/min, 30 K/min and 40 K/min, and the particle sizes of iron were 100nm and 20μm. The iron’s kinetic parameters of combustion reaction were calculated by Coats-Redfern integral, differential and Kissinger methods, then the kinetic model was determined and the most probable mechanism function was verified by Popescu method. The results show that different heating rates, particle sizes and calculations can affect kinetic parameters and reaction mechanism. The activation energy of 100nm and 20μm iron powder’s combustion is 122.48 KJ/mol and 161.64 KJ/mol respectively. The combustion reaction of micro nanometer iron powder is controlled by random nucleation and subsequent growth model which is in agreement with Avrami-Erofeev equation. Rational control for the temperature and reaction time are conducive to optimize the combustion reaction of micro nanometer iron powder.

Aquaculture can bring excess phosphorus to lakes which causing eutrophication. Figuring out the amount of phosphorus is meaningful to water pollution control. This study aims to clarify how much phosphorus is produced by aquaculture in Baiyangdian Lake each year. A phosphorus balance equation which is based on conservation of matter is established and used to calculate the input and output phosphorus carefully of an experimental field during a breeding cycle. Six parameters which are little fish, adult fish, feed, plants, sediment deposition and release are included in the equation. By the equation, the document gets a model: Q(x)＝0.033x, which shows that breeding every 1kg grass carp, there will be 0.033kg phosphorus into the water. As a result, the phosphorous pollution load of aquaculture in Baiyangdian Lake is 302.6 t/a.

The Ni/Carbon nanotubes (CNTs) composites for supercapacitor electrode have been synthesized by electroless deposition method. The morphology and structure of Ni/CNTs were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The nano-size Ni particles coated the surface of carbon nanotubes. Electrochemical performances of the synthesized composites were investigated by cyclic voltammetry and galvanostatic charge/discharge measurement. The specific capacitance of prepared electrode is up to 281 F/g, which is much higher than acetylene black electrode and pure carbon nanotubes electrode, indicating an effective path for increasing specific capacitance of carbon materials for the appplication of supercapacitors.

By using ANSYS software, the finite element model of the foundation for wind turbine generator system is built. On the basis of concrete elastoplastic constitutive, the non-linear contact between the foundation stub, a steel part, and foundation concrete is introduced, the internal mechanical characteristics and law of the foundation which is under the influence of wind with unfixed direction are researched on. The interaction state is attained. The numerical analysis considering the contact status and material nonlinearity is more reasonable and the research results offer scientific basis for the domestic autonomous designing and optimizing.

Proper pretest planning is a vital component of any successful CNC machine tools’ vibration test. An extremely important part of the pretest exercise is the placement of sensors. In general, the placement of sensors of CNC is uniform distribution, which depends on test engineer’s experience. This paper considers the problem of locating sensors on the CNC machine tools with the aim of maximizing the data information so that structural dynamic behavior of CNC machine tools can be fully characterized. We present a new technique, based upon Effective Independence (EfI) and Shannon’s Sampling Theorem, that can meet test accuracy requirements and the visualization of the mode shapes. The technique is applied on XHK5140 CNC machine tool successfully

Machine thermal equilibrium seriously influences the machining accuracy,a significant amount of research has been dedicated to the task of achieving and reasonablely controlling the thermal equilibrium time.In this paper,based on the analysis of the trait of thermal equilibrium process of machine tool ,the affection of room temperature and spindle speed on this process and the temperature when each point reaches to the heat balance is investigated.A new method of estimating thermal equilibrium time of each measured points based on spindle thermal model theory and multivariate optimization is presented,the results are analysed,further research about the control of machine thermal equilibrium process can be made based on this paper.

Cylinder compression pressure reflects the air tightness of engine. A method for measuring the compression pressure of cylinder indirectly through measuring the vibration signal of cylinder head was studied and then to detect the air tightness. The air pressure signal in cylinder and vibration signals of cylinder head were measured at the same time when the diesel engine was driven by the motor. According to port timing, the vibration signal excited by cylinder pressure was separated using time domain analysis. A RBF neural network model was set up to build the relation between compression pressure and cylinder head vibration. So the air tightness of cylinder can be detected after calculating the compression pressure by use of neural network.

With the continuous development of information technology and widespread of the Internet, e-commerce has become the mainstream business mode in the world economy. Under the context of e-commerce, enterprises are faced with enormous information resources, and the competition among the enterprises is also built on the basis of informatization, while business information safety is the essence of business informatization. The paper has conducted profound researches on the business information safety from three aspects: collection, application and management of information.

Basing on the theory of power flow, frequency response analysis was acted on in a hydropower house under dominant frequency with measured data of Three Gorges Station in spiral case and draft tube. Power flow in walls was calculated by APDL procedure and the properties were analyzed. The conclusion is that longitudinal wave is the main method in walls of the powerhouse, energy is reflected and stacked at the top of the walls. Displacement along the river changes and power flow in walls decays obviously. Intensity of vibration origin and distance between the vibration and the wall are both the influencing factors，increasing the stiffness of buttressed walls takes the role of limiting flexural wave and shear wave effect

A novel ZnO/ZnO-Bi2O3 nanocomposite was prepared by a homogeneous precipitation method. The nucleation sites, namely ZnO-Bi2O3 particles with nominal chemical composition of (ZnO)0.94(Bi2O3)0.06, were prepared by ball milling and subsequent annealing treatment. The as-synthesized materials were characterized by XRD, SEM and electrochemical measurements. Compared with single ZnO, the ZnO/ZnO-Bi2O3 nanocomposite show better cycling stability and higher discharge capacity. When the content of ZnO-Bi2O3 was 15 wt.%, the discharge capacity of ZnO/ZnO-Bi2O3 nanocomposite hardly declined over 60 cycling test, the average discharge capacity reached 590.2 mAh g−1. Cyclic voltammograms clearly illuminated that the added ZnO-Bi2O3 particles could decrease electrode polarization, maintain the electrochemical activity, and enhance the discharge capacity of ZnO.

A new kind of cathode materials, Li3V2(PO4)3/C nanocomposites, has been prepared via one-step solid-state reaction using ultra low-cost asphalt as both reduction agents and carbon sources. The asphalt is contained 60.37% of fixed carbon and 0.18% of other impurity.It is purchased from Zhen jiang Xin Guang Metallurgical Subsidiary Material Plant. Structural analysis shows that the obtained Li3V2(PO4)3/C nanocomposites contain abundant Li3V2(PO4)3 nanorods and micro/nano particles encapsulate with carbon shells. The Li3V2(PO4)3/C nanocomposites achieve enhanced dischargeability, reversibility, and cycleability. Electrochemical tests show that the Li3V2(PO4)3/C nanocomposite has initial discharge capacities of 170 mAhg-1 at 0.1C in the voltage range of 3.0 to 4.8 V. The improved electrochemical properties of the Li3V2(PO4)3/C nanocomposites are attributed to the presence of Li3V2(PO4)3/C nanorods and the electronically conductive carbon shell. This one-step solid state reaction using low-cost asphalt as carbon sources is feasible for the preparation of the Li3V2(PO4)3/C nanocomposites which can offer favorable properties for commercial applications.

This paper proposes a flux observer of voltage-current model based on PI regulator .Flux estimator value of current model at low speed is convergent gradually, so we adopt the current model. On the basis of traditional voltage model, we adopt improved model which substitute pure integral part with first-order inertia part and a compensation part, and it can solve DC drift and initial value with this method. Two models can be switched smoothly without concussion by setting appropriate PI parameter. The performance of the model is investigated and verified experimentally.

Amorphous porous FePO4·3H2O micro-spheres were synthesized via a controlled crystallization method. These micro-spheres have a particle size distribution from 10 to 28 μm. There are larger numbers of pores on the surface of FePO4·3H2O microspheres, which are important to synthesize high performance LiFePO4 cathode materials for the application of lithium ion battery. The electrochemical properties of the LiFePO4/C electrode, preparing by using the above porous spherical FePO4·3H2O particles, were measured. The electrochemical results show that the obtained LiFePO4/C has a high initial discharge specific capacity of 141.4 mAhg-1 and good cycling performance at 0.5 C. The microstructural and electrochemical analyses indicate that this porous spherical FePO4·3H2O is a fascinating precursor for preparing LiFePO4/C cathode materials.

Hexagonal phase NaYF4: Eu3+ materials were successfully synthesized by a facile EDTA-assisted hydrothermal route. The microstructure, morphology and luminescence property of the as-synthesized samples were characterized by XRD, XPS, SEM, TEM, HRTEM and photoluminescence (PL) spectra. The pristine NaYF4: Eu3+ microprisms have uniform size and morphology with 3-4 micrometers in length and ca. 500 nm in diameter. The annealing treatment afterwards achieved high crystallinity, and moreover, had a remarkable influence on morphologies of the NaYF4: Eu3+ sample. In comparison with the pristine sample, the annealed NaYF4: Eu3+ microcrystals had a markedly enhancement of down-conversion (DC) luminescence properties, which may be due to the high crystallinity and large surface roughness resulted from annealing treatment.

TiO2-xNx film was prepared by the combination of sol-gel and spin-coating method on indium-tin oxide (ITO) conducting glass substrate. Then an ITO/TiO2-xNx/NiO composite electrode was obtained by chemical bath deposition (CBD). The morphology, crystal structure and composition of the ITO/TiO2-xNx film were characterized by SEM, XRD, and XPS. The photoelectrochemical properties of the ITO/TiO2-xNx/NiO electrode were evaluated by photocurrent transient measurements and UV-visible transmittance spectra. The results showed that the ITO/TiO2-xNx/NiO electrode was sensitive to light and exhibited a noticeable photoelectrochromism.

The three-dimensional finite element numerical model of wind power generator unit is created by using ANSYS. The elastic-plastic constitutive is introduced and the nonlinear contact is set up between the foundation stub and concrete. The different reinforcement arrangement’s impact on structure is researched, the strength characteristic and law of reinforcement concrete is discussed and a more rational scheme is raised. It’s more rational to consider the contact status and material nonlinearity. The research results offer scientific basis for design and optimization on foundations of wind turbines.

It is revealed that the conventional reduced modulus used in depth-sensing indentation tests is invalid for a flat-ended cylindrical indenter due to the fact that the contact area during the loading is a constant irrelative to load. The load-displacement curve of flat punch is related to the length of the punch and the ratio of the elastic modulus of the indenter to the specimen (the modulus ratio Ei/E). Furthermore, theoretic analysis and finite element simulation demonstrated that, for conical indenter, the measured hardness from depth-sensing indentation tests would increase with increasing modulus ratio because the load increased with the ratio for the same displacement.

The transient temperature field and creep of concrete surrounding a spiral case are analyzed with a three-dimensional method, based on ABAQUS. The mechanism of hydration heat and cooling pipes on temperature is studied. The distribution of temperature with construction is given. The effect of temperature on gap between steel liner and concrete is researched. It is concluded that the influence of the measure parameters and temperature is indispensable.