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In order to conduct a further investigation of the causes of damages in large longitudinal slope of asphalt road pavement under actual heavy load, a three-dimensional finite element model was established by ANSYS finite element software. Through applying impulsive load in this model, the variation of the strains of large longitudinal slope of asphalt road pavement under different conditions was obtained and the influence of gradient on the dynamic response of large longitudinal slope of asphalt road pavement was analyzed. The results show that the strains of large longitudinal slope of asphalt road pavement increased with the increase of load times. Flexure tensile strain and shear strain were similitude with the change tendency of the increase of overloading rate but the data increased significantly. The transversal shear strain increased with the increase of gradient.

Vehicle detection is an essential task of environment perception. We proposed a vehicle detection method using the fusion of LIDAR and video for current traffic conditions. First, joint calibration of LIDAR and camera are introduced, the target area obtained by clustering of laser scanning data is projected into the image to get the region of interest (ROI). According to the analysis of vehicle symmetry, vertical edge statistics and template matching based on Hausdorff distance, the transitable area is distinguished. Vehicle detection algorithm is implemented in the united simulation condition of PreScan and Matlab/Simulink. Detection results show that the detection algorithm is robust and reliable.

For measurement and communication interrupt between earth station and reentry vehicle in blackout area, we analyze electromagnetic environment characteristic of plasma sheath. Methods of changing electrical characteristic of plasma medium or changing measurement and communication equipments are researched based on the analysis. Also technology of trajectory reconstruction is presented by using limited measurement data of target. The paper introduces technology status of measurement and communication for blackout area reentry vehicle. Also we analyze properties of common methods and propose key questions to research. It provides reference for related researchers.

In an effort to direction convert biomass by means of pyrolysis for fine chemicals as a substitute fuel, some inorganic matters were chosen to investigate the possibility of improving the catalysis of biomass pyrolysis. Inorganic acids are catalysts to be found effective for giving high selectivity to furfural chemicals.

Recently, electrospinning of nanofibers based on chitosan has been widely studied and numerous chitosan based nanofibers have been prepared, for the enormous possibilities of applications in various areas such as filtration, enzyme immobilization, tissue engineering, wound dressing, drug delivery, and catalysis. Because most of the chitosan based nanofibers are soluble in aqueous solutions and the other properties such as mechanical properties are not suitable for the further applications. It is necessary to improve the properties of chitosan based nanofibers. Various post-processing has been done to the chitosan based nanofibers and many post-processing products have emerged. This article discusses the post-processing of the chitosan based nanofibers involving methods, mechanisms, changes of nanofiber properties, and applications of the post-processing products in details. The post-processing is divided into alkali treatment, crosslinking, and functionalizing.

EPC have an important role in promoting energy conservation and emission reduction in China. With the rapid development of the energy services industry, ESCOs faced with the problem how to make investment decisions about pricing and performance levels. This paper reference one monopoly pricing and performance level joint decision model into a single market, put forward the EPC price and performance level joint optimal decision model, and then solves it to obtain the optimal price and the best performance level. Lastly we take a numerical example to analyze Energy Service Companies (ESCOs) how to choose the performance level to obtain maximal profit. Result show that price sensitivity and performance level sensitivity of demand have an impact on the performance level choosing ; the highest rate of return on investment and maximum profit could be obtain at a lower performance level.

Identification and amendment dangerous driving behavior timely and accurately is a necessary means to reduce traffic accidents. This paper proposed a dangerous driving behavior identification method based on neural network and Bayesian filter. By using vehicle-mounted radars and cameras obtain movement state information of the vehicles around the host vehicle and lane line distance data, on the basis of which, the identification model is established. Then evaluate model performance by the real data. The test results show that after the correction of neural network output by Bayesian filter, the model accuracy has a sharp rise.

Bias flow is an important parameter in a flotation process of packed column. An experiment related to P2O5 recovery of phosphate rock was designed to study the effect of bias flow on the flotation separation efficiency by a direct-reverse flotation circuit of packed flotation column. The results have showed that the recovery of P2O5 is high during the combination of the direct-reverse flotation circuit. The grade and yield of P2O5 can reach to 32.77% and 82.64% respectively, under the condition of the range of-0.005~0 cms-1 of bias flow, 0.013~0.020 cms-1 of the wash water flow rate in the direct flotation column, and the range of 0.006~0.009 cms-1 of bias flow, 0.027~0.035 cms-1 of wash water flow rate in the reverse column.

In order to make a further understanding of flow pattern and back mixing in the flotation process, the study about particle residence time distribution of collection zone in a packed column has been designed. The pulse tracer method was applied and the particle tracers were the mineral gangue in special size class. The residence time distribution curves of our experiment data shows that there are particle back mixings which were caused by fluid flow and geometry factors in the column. The tank-in-series model has a better fitting to the particle residence time distribution in the column according the comparison research between the tank-in-series model and axial dispersion model. The operation parameters have different effects on the particle residence time distribution according to our experimental study.

As a new effort, combined reactive sintering with hot pressing technique, the Ti-22Al-25Nb alloy was successful prepared with element mixed powders. Meanwhile, the reactive sintering was divided into two temperature ranges, which were at 873 K and 1373 K, respectively. The starting sintering kept 1h at 873K, and then the temperature was increased to 1373K, keeping 2h. The orthorhombic (Ti2AlNb) phase was observed in this sintered alloy. Moreover, the homogenization treat was conducted at 1473 K for 2h after the final sintering was accomplished, and the fraction of the orthorhombic phase increased significantly. The microstructures and the phases were analyzed. And the generation mechanism of the orthorhombic phase was also analyzed.

The expression level of chicken β-defensin Gal-3 was influenced by lactose concentration, induction time and initial cell density, and IPTG induction was used as a control. The optimal parameters of various factors were confirmed. the optimal parameters with lactose induction was 37°C of culture temperature, 2 g/L of joining lactose final concentration when the recombinant strain growth density A600 achieved 0.8 and induction maintained 3 hours, the production of fusion protein reached the highest level. This study provides a good experimental basis for the large production of Gal-3.

With the completion of Three Gorges Project, the power system in China is forming a huge AC/DC network. In the hybrid AC/DC parallel transmission system, a line fault will cause fluctuations even crash of the system. The HVDC transmission system based on the emergency DC power support (EDCPS) can provide a fast emergency power support for the interconnected AC power grid flexibly and improve the stability of AC power. A model of AC/DC hybrid transmission system is established in the PSCAD/EMTDC simulation environment. An improved PID controller is firstly introduced to the hybrid AC/DC transmission system. The simulation result shows the EDCPS has an obvious effect on keeping the voltage stability of the system.

A new method that phosphate ore was reduced by carbon under fluidization was introduced to produce yellow phosphorus, and we made thermodynamic analysis of the process and investigated the effect of coke content, flow of nitrogen gas, and temperature on percent reduction of phosphate ore. The thermodynamic analysis indicated that the beginning reaction temperature of phosphate ore with mole ratio of silica-to-lime equal to 3 decreased by 8.8°C with increasing 0.1 atm N2 partial pressure when the system total pressure was 1 atm. The experiment results showed that percent reduction of phosphate ore increased with increasing the coke content, the flow rate of nitrogen gas below 600 L/h and the temperature. The reduction rate in the fluidized bed reactor was better than that in a fixed bed under the same temperature, particularly lower temperature. The temperature was a dominant factor, the influence of which on reaction was greater than any other factors.

The urea dosing unit in the diesel engine SCR system, real-time calculates and delivers the quantitative urea , which is vital to the reduction of the NOx emission. Considering the practical condition, according to the function of the urea dosing unit, based on the pump controlling quantitative and air assisted atomization principle, the mechanical part of dosing unit is designed. Also based on the consideration with versatility and openness of the unit, the control part of dosing unit is designed. At last, based on the the common and open platform founded by designed urea dosing unit, which is composed of mechanical part and control part, the SCR control module and dosing module are developed. At last, the designed dosing unit is examined by the engine ETC test. The ETC test results indicate the design achieves the intended purpose.

To get a better understanding of tracking capability and accuracy of the equipments onboard space tracking ships, it is necessary to perform precision evaluation. In order to achieve satisfactory results, dynamic flight experiment is organized, during which a series of new methods and technologies are applied, with GPS carrier wave phase difference technology as the center, among which GPS data processing technology is empathized. Based on above, a set of complete GPS data processing models for precision evaluation are established

The effect of different additives on thermal decomposition of phosphogypsum was investigated by means of a thermogravimetry coupled with a Fourier transform infra-red spectroscopy. These additives included C, CaO, Al2O3 and S. The temperature of thermal decomposition of phosphogypsum is about 1100~1320°C without any additives under the background of nitrogen. The temperature of the thermal decomposition of phosphogypsum decreased obviously with the addition of CaO, C and S. No influence was found for the thermal decomposition of phosphogypsum with the addition of Al2O3. As one of evolved products from the thermal decomposition of phosphogypsum, SO2 production was discussed.

The numeric method of the total quantity of ineffective reflux on tower top of binary batch distillation of total reflux and top accumulation under and ideal operation conditions is introduced. Energy consumption of binary batch distillation under total reflux and top accumulation is analyzed using the calculated results of examples，and a conclusion that, for the separation task that the low-efficiency energy consumption is large in proportion to its total energy consumption , its total energy consumption is visibly reduced by making a reduction in the mixing level of flowing liquid in top vessel.

Effect of copper compounds on the catalytic activity of n-Bu2SnO in the transesterification of dimethyl carbonate and phenol to diphenyl carbonate was investigated. The results showed that they as promoters could obviously enhance the activity of n-Bu2SnO except for Cu. The characterizations of X-ray diffraction (XRD) identified that CuO could be reduced to Cu, and Cu2O was stable. When the reaction was carried out between 150 and 180 oC, with molar ratio of n-Bu2SnO to Cu2O of 8:1, catalyst amount 0.0067, reaction time 10h, molar ratio of dimethyl carbonate to phenol of 3:1, the phenol conversion and the transesterification selectivity were 60.3% and 99.2%, respectively. In the transesterification, the acid-base synergistic effect between Cu2O as the basic promoter and n-Bu2SnO as the Lewis acid resulted in the active enhancement of n-Bu2SnO. Moreover the performance of Cu2O remained unchanged for seven times reuse.

A meshless natural neighbour Petrov–Galerkin method (NNPG) is presented for solving the elasticity problems in this paper. In a certain domain, a discrete model consists of a set of distinct nodes, and a polygonal description of the boundary. The natural neighbour interpolation has Kronecker delta function property, and the construction of local sub-domain is simple both for internal nodes and boundary nodes. The whole interpolation is constructed with respect to the natural neighbour nodes and Voronoi tessellation of the given point. A local weak form over the local Delaunay triangular sub-domain is used to obtain the discretized system of equilibrium equations. The numerical results show the presented method is easy to implement and very accurate, especially for solving the problems of crack propagation or large deformations.

In order to observe the influence of monomer on the printing quality of UV waterless offset ink, ink samples with different monomer were made, and the main performance parameters such as viscosity, thixotropy, yield value, fluidity and stickiness were tested. Proofing by printability tester, and the printing qualities such as solid density, gloss, dot gain and print contrast were tested. Analyzing the influence of the difference of ink performance that caused by monomer on the printing quality of UV waterless ink. The results show that ink performances affect the printing quality directly. The differences of monomer’s structure and functionality have great effect on ink’s performance such as viscosity, thixotropy, yield value, fluidity and stickiness, and it can lead to the difference of printing quality such as solid density, gloss, dot gain, and print contrast.

Since the Energy Performance Contract (EPC) includes complex structure, many members and serious asymmetry information, it is reasonably practicable to ensure its efficient and stable operation preconditions to establish information-sharing model. In this paper, we use the way of information flow to research the sharing information model in EPC. The result shows that the bases of sharing information are the set of sharing scope and order splitting. Accordingly, we put forward the sharing information platform of energy service information integration in EPC and constructing tactic.

With the increasing public environmental consciousness, chemical product design requires simultaneous satisfaction and compromise of environmental and economic performance. To fulfill the two conflicting while complementary objectives, a systematic approach for life cycle design of chemical product is proposed in this paper. Multi-attribute decision-making is adopted in a trade-off consideration of both technical-economical evaluation and environment impacts assessment with the analytic hierarchy process approach. Based on the evaluation of relative importance of criteria, multi-criteria decision making is performed.

The distributed database system is the product that the database system combines with the computer network system. The data distribution problem has great influence on distributed database application system improvement, data availability, the efficiency and reliability of the distributed database. The allocation strategies in this paper have used some excellent properties in genetic algorithms, including higher parallelism and robustness, the realization of standard way, and to maintain good balance between the depth prior search and breadth prior search, etc, so the allocation strategies in this article's have high execution efficiency, with stronger ability in seeking the best global solution and easy to realize.

The solubility of 8-hydroxyquinoline lead, lead diethyldithiocarbamate, 8-hydroxyquinoline mercury and mercury diethyldithiocarbamate in supercritical carbon dioxide under different supercritical conditions was investigated by using supercritical extraction device. It was measured ranged from 308.15K to 328.15K for supercritical temperature, and 10 MPa to 30MPa for pressure. The solubility data of metal complexes were correlated and a mathematical model was put forward from a viewpoint of solvent association theory compared to Chrastil’s model. The results showed that SA model gives fairly good agreement with the experiment data.

Supercritical CO2 chelating-extraction was applied to remove heavy metal matter such as Pb, As and Hg from calcium lactate, and the effect of process parameters on removal efficiency were investigated including chelating agent, ethanol (as a modifier), temperature, extraction pressure and time. The results showed that the removal efficiency of trace heavy metals is obviously different from chelating agent, modifier and extraction time, thus the concentration of modifier and extraction pressure give little influence. The extraction process was optimized to get the condition of a temperature of 323.15K, a pressure of 20MPa, an extraction time of 90min, a supercritical CO2 fluid flow rate of 13l/h and 2% of the chelating agent mixtures combined with tetrabutyl bromide and sodium diethyldithiocarbamate (DDC). The maximum yield of Pb, As and Hg can reach 88.41%, 78.57% and 86.21%, respectively.