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A one-step synthesis of visible light responsive diatomite/g-C3N4 composite material was prepared by impregnation-calcination method. The products were characterized by Scanning electron microscope, X-ray diffractometer, Ultraviolet diffuse reflectance spectroscopy, Fourier transform infrared spectrometer, and Photoluminescence spectrometer. The SEM results showed that g-C3N4 was successfully attached onto the surface of the diatomite. Also the composite materials were more light-responsive compared with the single phase material. The composite materials had a maximum degradation efficiency up to nearly 91.79%. The significant improvement in photocatalytic performance was due to the porous structure of diatomite, increase of contact area of carbon nitride.

Amphiphilic functionalized montmorillonite (MMT) has been employed in hydrophobic compounds delivery systems. In the present study, MMT intercalated by 3-aminopropyl trimethoxysilane (APS) was employed for the delivery of the model compounds of resveratrol (RSV). The structure and surface morphology of APS-MMT were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, thermogravimetry, scanning electron microscopy, and contact angle analysis. The loading and release efficiencies of RSV were also investigated. Our study showed that the aminosilane-modified MMT is promising for use in poorly water-soluble compounds carrier systems owing to their natural and excellent performance.

Within the vehicle transmission, the friction surfaces of mechanical parts were consecutively worn-out and ultimately up to the degradation failures. For assessing the wear progress effectively, wear particles should be generally monitored by measuring the element concentration through Atomic emission (AE) spectroscopy. Herein, the spectral data sampled from life-cycle test has been processed by both the Principal Component Analysis (PCA) and further Kernel Principal Component Analysis (KPCA). Results show that KPCA acts more effectively in variable-dimensions reduction due to fewer principle components and higher cumulative contributing rate. To detect the threshold point at where the wear-stage upgraded, the Fuzzy C-means clustering algorithm was applied to process the eigenvalues of principle components. Furthermore, it is demonstrated that the principle components relate to the worn-out state of friction pairs or transmission parts. In general, the introduction of KPCA has contributed to assess the wear-stage at where the machine situates and the accurate worn-out state of various transmission parts.

Recently, noble metal nanoparticles (Au or Ag NPs) decorated graphene (GE) sheets are used as good surface-enhanced Raman scattering (SERS) substrates for detection of molecules. Ultrathin GE film covered by Ag NPs has been designed for the SERS substrate in this paper. The films were prepared firstly by dip-coating method with graphene oxide (GO) and AgNO3 or Ag NPs colloid as raw materials and secondly reduced by thermal annealing at 600 °C in H2/Ar atmosphere. The structure and SERS activity of the obtained films have been investigated in detail. Results indicated that Ag NPs can be decorated on graphene sheets through the electrostatic adsorption between the GO sheets and positively charged Ag+ or Ag NPs. Compared with the film obtained with AgNO3, Ag NPs/GE film prepared with Ag NPs colloid showed the higher SERS sensitivity with rhodamine 6G (R6G) as the probing molecules, the enhanced factor for 1×10-5 M of R6G adsorbed on the surface of Ag NPs/GE substrate is about 9.1×107.

According to the configuration characteristic of high-power transmissions and working principle of multi-plate shift clutch, the clutch dragging process is analyzed at first in this paper. After introducing the usual monitoring method of clutch dragging process, a portable vibration monitoring method is proposed. And then a GMDH forecast method on the basis of the morbidity index is presented. The practical application of the method can reduce the probability of clutch invalidation, and significantly extend the clutch’s working life.

In this article a surrogate model between suspension system parameters of tracked vehicle and comfort evaluation indices has been built up by using radial basis function method and the dynamic simulation of tracked vehicle. Then the optimization of suspension system parameters has been carried out by using surrogate model and adaptive simulated annealing optimization arithmetic. The results show that the research method is feasible.

Consumer reviews have been considered as a golden mine which can be used to analysis consumers preferences, attitudes and opinions about products or services or online stores. How to exploit this mine effectively has attracted researchers attention. In this paper, a new classification method based on fuzzy cognitive maps is proposal. The experience results showed the approach is more effective way of classifying Chinese reviews based on calculating the precision rate and the recall rate.

The thermo-elastic coupling model of clutch friction pair is established by the thermoelastic instability theory to acquire the basic process of friction disc warp due to hot agglomeration; according to this process, thought of reflecting initial phase clutch fault by observing the partial deformation generated by hot spots is proposed in this paper. And based on this thought, the multi-disc clutch dynamics simulation model is established to acquire the dynamic characteristics existing on the friction pair when tiny deformation happens; according to vibration characteristics of this characteristics and the feature that the interference noise of the high frequency section of the transmission system is comparatively light, and based on the analysis on the difference of frequency spectrum of the high frequency section before and after shifting gears, a new kind of initial phase multi-disc clutch fault diagnosing method based on vibration signal analysis is proposed. The test results further prove that, this method can be used to extract the impact vibration generated by tiny deformation happened on the friction pair, and is hopeful to be used in the practical engineering of initial phase multi-disc clutch fault diagnosing.

The paper used decision tree automatic threshold classify model to study land use and land cover in Shangri-la County with Landsat ETM+ image in 1999, and got two results. The first result is the land use and land cover map, the second result is the surface features area statistical result from large to small: bush, spruce and fir, meadow, pinus densata, ice and snow, pinus yunnanensis, unutilized land, paddy field, town, dry land , marsh, water. Bush has the largest area, 4267492200m2, while water has the smallest area,6147900m2.

In this paper, we have considered a viral infection model with delayed CTL response and cure rate. For this model, we have researched the stability of these three equilibriums depend on two threshold parameters and , that is, if , the infected-free equilibrium is locally asymptotically stable; if , the infected equilibrium without CTL response is globally asymptotically stable; and if , the infected equilibrium exists, at he same time, we have found that the time delay can lead to Hopf bifurcations and stable periodic solutions when the is unstable.

Laboratory Virtual Instrument Engineering Workbench is a graphical programming software exploited by NI company with powerful real-time data processing and analysis functions. The paper focuses on the thread for designing and main function of serial communication module based on Laboratory Virtual Instrument Engineering Workbench and describes the function and use of the VISA function in Laboratory Virtual Instrument Engineering Workbench. Experiments show that the serial communication module is convenient, powerful, and of good portability and scalability.

The vibration character is analyzed with the methods of harmonic wavelet and time domain indexes of reconstruction with simulation signal and test data. Using harmonic wavelet compactly supported characteristic and box spectrum, the data is rebuild with some specific frequency wavelet coefficients. This not only realized the frequency domain filtering, the time domain information is also retained. The analysis of time domain indexes shows the method can identify the vibration amplitude growth derived from the noise or from the useful signals. The simulation and experimental results confirm that, with the harmonic wavelet reconstruction signal time domain indexes, the gear fault detection and diagnosis can be achieved under the condition of strong noise.

This paper investigated the dynamic pressure distribution on the plates within a wet shift clutch in hydrodynamic machineries for one engagement. The perturbation pressure model, heat conduction model and pressure calculation model excited by thermoealstic instability was developed. And wrote calculation programs with Maple 15 to analyze the influence of two kinds of typical friction materials, different thermal conductivity, different initial engagement speed on perturbation pressure amplitude and its impact on the pressure design margin and design radius. The results show that the margin can be decreased and design radius can be reduced, so power density increased. When the slipping speed is controlled within 16m /s, the radius can be reduced to about 1/2 of the original value.

This paper presented an adjustable analog predistortion linearization method for RF power amplifier. The linearization includes an attenuator, a phase shifter and an anti-parallel Schottky diode pair with DC bias, through adjusting these components, we can adjust predistortion characteristic of the linearization to be complementary to distortion characteristic of RF power amplifier. By cascading this linearization with power amplifier, we can improve linearity of amplifier. Firstly, we simulated the proposed predistortion linearization with software ADS, then the linearization was manufactured and tested together with RF power amplifier PTF080551. Experimental results show that we can adjust predistortion characteristic of the linearization to be closely complementary to distrotion characteristic of power amplifier PTF080551 as desired. After cascading the linearization with power amplifier PTF080551, more than 10dB improvement in IMD3 of the amplifier can be achieved. Furthermore, the linerarizaion is flexible and can be adjusted to linearize different amplifiers.

A synchronization control strategy with cross-coupling concept for tracked vehicle with hydrostatic drive is developed and compared with a leader-following control strategy, aiming to achieve stable straight running. Associating with the basic controller, the two kinds of synchronization controllers are designed. Dynamic system model containing the control strategy for entire tracked vehicle is modeled in MATLAB/Simulink, the results of simulation indicate that, compared with leader-following control strategy, the cross-coupling strategy can restrain synchronization error more effectively and make the system more stable obviously under external disturbances by coordinates the motion of two drive loops simultaneously.

Using the finite element method, influences of vehicle load, subgrade fillings and compactness on the subgrade work zone were analyzed, of which the traffic load impacts most. Considering the traffic and mechanical character of the subgrade, it is determined that the appropriate subgrade work zone depth of rural highway is 1.0m. As a result, applying proper work zone depth plays an important role in the construction cost of rural highway.

Directly mixing the PCM to asphalt mixture may adversely affect mixture performance. By the experiment of SEM, the diffusion-absorption circle testing and the DSC, the micro-morphology and the adsorption characteristics to PCM of four carriers and the thermal properties of the composite shape-stabilized phase change materials (CSPCM) were analyzed. The results showed that the activated carbon, the floating bead and the white carbon black have more developed porous structure. The white carbon black has the best effect on the adsorption of PCM. The shape-stabilized PCM prepared by the physical adsorption method has the leakage problem. The CSPCM with the white carbon black carrier has the best heat storage capacity. The white carbon black is the best carrier of PCM for asphalt mixture.

Non-magnetic steels are required in energy and transportation fields such as superconducting energy storage equipment, magnetic liquid power generation equipment, superconducting generators, superconducting power transmission and ship electromagnetic propulsion. Experimental research on steel making, hot rolling, solution and aging for non-magnetic steel 30Mn27Al4V was carried out in the laboratory. The microstructure evolution was observed and the mechanical property and relative magnetic permeability were tested after heat treatment. The effects of fine particles such as VC, VN and V(CN) dispersively distributed in austenite matrix on precipitation, grain refinement and austenitic nucleation were analyzed. The microstructure of the tested steel is austenite. The grain size is 24~28μm. At room temperature, the yield strength and tension strength are 556 MPa and 701 MPa, elongation after fracture of the steel is 47%, the yield ratio is 0.79, strength and ductility product is 32.9 GPa%. After solution and aging treatment, the steel shows a yield strength of 325~371 MPa, tension strength of 550~645 MPa, elongation of 58~78 %, a yield ratio of 0.54~0.60, strength and ductility product of 36.3~46.3 GPa%. The relative magnetic permeability is below 1.005. The results indicate that the tested steel exhibits good mechanical property and non-magnetism. It has no elements of Ni and Cr, so it just needs simple process flow and lower production cost. The numerous applications of the steel in industry can create great economic benefits.

In this study, the combustion behaviors of three kinds of coal and their mixtures under the pure oxygen and air atmosphere were studied by using a thermo-gravimetric analyzer. The combustion characteristics such as ignition and burnout behavior were investigated in the temperature from 20°C to 800°C. The influence of mixing Shenhua coal with Huaibei bituminous and Sanming anthracite coal on combustion characteristics was conduced. The results obtained show that pure oxygen content accelerated the coal burning process greatly; the coal volatile matter started to release at a lower temperature and the coal burning process was finished earlier compared with the burning process under the air atmosphere. The addition of Shenhua coal improved the combustion characteristics of both Huaibei bituminous coal and Sanming anthracite in a different way. For the Huaibei bituminous coal, both the ignition and burnout temperature decreased linearly with the increasing ratio of Shenhua coal; while for the Sanming anthracite, the addition of Shenhua coal greatly lowered the mixture ignition temperature, and the burnout temperature was nearly the same. The activation energy of the mixture coal with Shenhua and Huaibei coal reduced with the ratio of Shenhua coal. For the Shenhua and Sanming coal mixture, the activation energy changed differently at the two burning stages.

It provides a new way to solve the worldwide the low-temperature cracking and high temperature rutting distresses of the asphalt pavement, by mixing the composite shape-stabilized phase change material (CSPCM) to asphalt mixture. The effect of CSPCM on the temperature of asphalt mixture is analyzed by the monotonic cooling test, the monotonic heating test and the outdoor simulating cycle test. The results of monotonic cooling and heating tests indicate that mixing CSPCM into asphalt mixture can increase the temperature of asphalt mixture during cooling process and decrease the temperature of asphalt mixture during heating process. It has a temperature damping effect as well. The results of outdoor simulation test shows that mixing CSPCM into asphalt mixture decreases the maximum temperature of the bottom of the specimen and increases the minimum temperature of the bottom of the specimen. It cannot change the critical temperature occurring time of the bottom of the specimen. The test results indicate that mixing CSPCM into asphalt mixture could actively adjust the working temperature of asphalt mixture, prolong the ideal temperature of asphalt mixture and improve asphalt mixture’s adaptability to the changing environment.

Both the government and the firms are concerning about the development of cyclic economy for highway projects construction. However, the huge investment risks and technology spillover are primary obstacle for developing and research of energy saving and emission reduction. This paper introduces the theory of the dynamic game of complete information to analyze how the government provide sufficient subsidy and make preferential policy to promote the firms to do it for their own interests. According to the establishment of sub-game perfect Nash equilibrium under non-corporative conditions, it indicates clearly that the most effective measures to make sure the firms to develop cyclic economy is that the government should maintain the highest rate of subsidies to the first firm who is willing to developing the energy saving technology.

Mixing the phase change material (PCM) into asphalt mixture could change the thermo physical properties of asphalt mixture. Asphalt mixture with PCM can remain in the ideal working temperature range for a relatively long time. However, the PCM easily leaks from asphalt mixture in the process of using. To solve this problem, the carrier-adsorbed packing method is applied to modify PCM in this paper. Different carriers and packaging materials are used to prepare three kinds of composite shape-stabilized phase change energy storage material (CPCM). Their microscopic characteristics and thermo physical properties are analyzed by scanning electron microscope and differential scanning calorimetry, respectively. The results show that the gel of silicon incompletely packed the macropores of activated carbon and the clustered silica, and the ethyl cellulose completely coated the clustered silica whose particle size increases and particle surface forms a compacted thin film. The phase transition temperature and latent heat of CPCM with silica are higher than CPCM with activated carbon. The PCM absorption of silica is greater than the PCM absorption of activated carbon. The mass fraction of CPCM packed by the EC is larger than the CPCM packed by the gel-sol method. The results indicate that the carrier-adsorbed packing method can effectively solve the problem of PCM leaking from asphalt mixture. The CPCM prepared with silica and ethyl cellulose is the most suitable for asphalt mixture.

Concrete interlocking block pavement is characterized of preferred durability, easy construction and maintenance and low construction cost. It can be widely applied in the rural highway. Based with the project of rural highway in Tongchuan Shaanxi province, the paper studies the mechanism of interlocking blocks, design of the pavement, and construction technology for field application. After one year service for open traffic, the interlocking block pavement is shown to have fascinating economy and service performance for the rural road.

Mixing the composite phase change material (CPCM) to asphalt mixture is a new way to solve the worldwide problem of the low-temperature cracking and high temperature rutting of the asphalt pavement. Asphalt mixture with CPCM can remain in the ideal working temperature range for a relatively long time. This paper analyzes the influence of the contents of CPCM on its road performance by laboratory testing. The study shows that mixing CPCM to asphalt mixture had little effect to the optimal asphalt content. For CPCM prepared by polymer shape-stabilized method, the high-temperature stability and the water stability of asphalt mixture increases firstly and then decreases the low-temperature anti-cracking stability decreases firstly and then increases with the increasing of CPCM. For CPCM prepared by carrier-adsorbed packaging process, the high-temperature stability decreases, low-temperature anti-cracking stability decreases firstly and then increases, the water stability increases firstly and then decreases with increasing of CPCM. The results indicate that CPCM has significant influences on its road performance. The optimal content of CPCM is around 0.3%.

Finite element analysis (FEA) method is used to study the mechanical properties of headed studs for composite truss joint. The results show that the shear forces in the first few rows of headed studs are much greater than others. The shear forces in the rear headed studs decrease gradually. This study shows that the stiffness of headed studs, the layout of headed studs, and the steel backing plate are the main influencing factors on shear forces of headed studs. It is also expected that the results presented in this paper would be useful as references for the further research and the design of composite truss bridge and composite joint.

Traditional lead brass is gradually prevented from application by many countries’ governments because lead does harm to human health and pollutes the environment. New types of environment-friendly lead-free brass with favorable machinability are urgently demanded in the electrical, electronics and plumping fields. Lead-free Mg-Sb brass was fabricated in present. Experimental results showed that when the content of Mg is 1.0wt%, Sb is 0.8wt% and Cu is 58.0~59.0wt%, the alloy’s mechanical properties and machinability are favorable for industry application. With the increase of the content of Sb, the machinability increased, while the mechanical properties decreased. Lots of Cu2Mg and Cu9Sb2 particles on the order of microns exist in the inner-grain and grain boundaries. These particles improve the machinability, however, lower the tensile strength and the elongation. A three-way pipe joint was successfully punched with the fabricated Mg-Sb brass bar, and this demonstrated that the fabricated Mg-Sb brass possesses favorable hot working property.

A soft rock is generally prohibited to be used as filling material for highway subgrade. A novel method for improving the performance of subgrade is proposed. Aiming at the large amount of highly weathered soft rock along Shiyan-Tianshui superhighway, the physical and mechanical properties of the natural soft rock is analyzed. Then the cement is mixed into the soft rock as filling material to better the subgrade performance.The field and indoor experiments showed that the maximum dry density and optimum water content increases when the cement content increases. By mixing the cement, the subgrade performance can be significantly improved.

With Monte-Carlo theorem, inclusive of the uncertainty of double phase geo-material parameters as well as math model boundary condition, stochastic difference math model was carried out for bulk terrestrial underground water seepage on the basis of plain confined steady underground water flow math model. The key conclusions are: seepage field behavior has close relation with turbulence of random B.C.; distribution of stochastic head potential depends on the geo-born-variation of parameters and the methods introduced in this paper are applicable for this achievement.

The application of Phase Change Material (PCM) to asphalt mixture can lighten the temperature-dependent disease of the asphalt pavement and improve the usability as well as extend the operating life of it. We choose agreeable PCM with comprehensive consideration to the technical requirement of its application in the construction industry and the characteristic of asphalt mixture. Through simulating temperature experiment, we make a conclusion that incorporate the carrier accompanied PCM into asphalt mixture can reduce the increasing rate and cooling rate of the mixture, which shows that PCM can put into use of adjusting the asphalt mixture operating temperature, softening the negative influence of ambient temperature variation on asphalt mixture.

The main span is the steel truss and the side spans are the composite truss in Minpu Bridge. A 1:2.5 model is made to study the mechanical behavior of the joint segment of steel truss and composite truss. Both a model test and a numerical finite element analysis(FEA) method have been conducted. The results show that the joint segment remains in a linear elastic state under the condition. The maximum stress in the structure is less than the material allowable strength. The FEA results are in very good agreement with those of model test. This study shows that the force transformation of the joint segment is reliable and the composition details are rational. It is also expected that the results presented in this paper would be useful as references for the further research and the design of composite truss bridge and joint segment.