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For the engine maintenance enterprises, the test of aeroengine test can detect the performance of the product more accurately, but the engine testing work is a weak link. Conventional piston aircraft engine test system is the simulation instrument, according to the observed by human eyes, manual way to complete data collection work, this test system is inefficient. The engine bench test automatic measurement and control and monitoring system based on computer control is the inevitable trend of its development. Data acquisition module transmits the real-time data from the engine sensor installed on the different parts to the PC through CAN bus and display on the PC. The engine test bed control system and data acquisition system simplifies the system structure and obviously improves the test level and efficiency of the system.

The use of clean alternative fuel and new combustion mode is one of the most effective methods of further reduction of NOx and smoke emissions at diesel engine. High thermal efficiency and ultra-low NOx and PM emission of engine in HCCI combustion mode can be realized at low and medium load. However, some problems such as hard control of ignition timing and narrow operating range still exist.For the sake of expanding the operating range of HCCI (Homogeneous Charge Compression Ignition) engines and explore the scientific methods to realize the ultra-low emission with DME (Dimethyl Ether) as alternative fuel. Experimental Research on the characteristics of PCCI-DI (Partial Premixed Charge Compression Ignition – Direct Injection) combustion is carried out on a single cylinder and naturally aspirated direct injection diesel engine. Results indicate that PCCI-DI DME engine has lower peak cylinder pressure and lesser rise rate of pressure. The engine also shows up an obvious two-stage heat-release characteristic. Compared with HCCI DME engine, peak value of two heat-releases reduces, the position of the first peak almost has no change and the position of the second peak shifts to the position later than TDC (Top Dead Center).

Performance test of the engine fueled with DME-methanol blends was conducted on a 4102BQ diesel engine. The results show that: by increasing the fuel pump plunger diameter, delaying injection timing, and reducing nozzle-opening pressure, the rated power of the engine, fueled with DM90 blends (Mass ratio of DME and methanol is 9:1), descended 13.97% relative to the original diesel engine, but the soot emissions did not appeared in all test conditions. In full load condition, NOx emissions declined by 55.1%, CO emissions fell by 65.8%, but HC emissions increased by 21.6%.

To further study the performance of the engine fueled with DME-diesel blends, the indicator diagrams of a two-cylinder four-stroke engine are recorded at 1700r/min and 2300r/min under different load, the heat release rate and the rate of pressure rise are calculated. The results show that: when fueled the engine with D20 blend (Mass ratio of DME and diesel oil is 2:10) and optimizing the fuel supply advance angle, the maximum cylinder pressure decreases by 10% averagely and its corresponding crank angle delays 2°CA, the maximum rate of pressure rise is relatively lowers about 20%, the beginning of heat release delays，but combustion duration do not extend, and the centroid of heat release curves is closer to TDC (Top Dead Center), maximum combustion temperature drops 70-90K. These results indicate that the mechanical efficiency will be improved and, NOx emissions and mechanical noise will be reduced when an engine fueled with DME-diesel blends.

The polyurethane buffer is widely used in mechanical industry, intelligent manufacturing, internal combustion engine industry and etc.. The parameter design of the polyurethane buffer is often based on empirical formula with which it usually can not obtain the optimal parameter. This paper aims at studying the process of the buffer and optimizing its parameter. Firstly, the result of compression and shear tests of the polyurethane material is compared with simulation result to validate the simulation method is reasonable. Then buffers of different sizes with practical condition were simulated. During the simulation, this paper researched the maximum deceleration of the mass block in models with different sizes of polyurethane buffers. Lastly, the size of the buffer with minimum volume which is agreed with the request of the maximum deceleration of the mass block is obtained by data handling based on the simulation result, above on which a database was built.

According to the dynamic compaction project of Beijing Garden EXPO Park, an experiment is designed to monitor the deformation and vibration range impact by dynamic compaction.The vibration velocity, vibration acceleration, settlement and deep horizontal displacement of the foundationare obtained through the continuous real-time monitoring during the experiment.In this paper, the expression of vibration velocity and acceleration decreased by distance is established according to the experimental data, besides, the relation ofsingle settlement and total settlementof tamp pit changed with hit numbers is also achieved.The study shows that,under the 3000kJ compact energy,the settlement range is about a circle with radius12.7m; the deep horizontal displacement changes only in range of radius 7.7m; the safety distance of vibration is 47.7m, and to fulfilling the requirement of consolidation 7 hits is appropriate. The study provides a reference to dynamic compacting processof this project.

Applied self-prepared GY dispersant into 75% thifensulfuron WDG formulation,only chang the dispersant and filler content, found out the optimal amount of dispersant using zata potential analyzer. The results show that when the dosage of dispersant is 6%, zeta potential to achieve the most negative,75% tribenuron water dispersible granule apparent suspension rate of more than 90%. Zata potentiometric method is a rapid method that decide anionic dispersant dosage.

Designed a monitoring system for Electric Vehicle battery controller to calibrate the parameters and detect the faults. The Monitoring System consists of host monitoring software and USB (Universal Serial Bus) 2.0 interface module. Programmed by C#, host monitoring software provides a UI (User Interface) to display the status of the battery controller and send the command to it. USB 2.0 interface module uses the chip Cy7C68013A to transfer data between the host monitoring software and battery controller. Tests showed that the monitoring system supported hot Plug and Play, high speed mode and easy portability. This system greatly reduces the user operating difficult, and improves the battery efficiency.

The 1,3-benzenediol and ethyl acetoacetate as raw materials were used to synthesize 7-hydroxy-4-methyl coumarin under microwave irradiation with Zirconium sulfate tetrahydrate as the catalyst. The effect of various reaction conditionson on the yield was explored.Experiment shows that the yield reached up to 87. 5%,when the reaction conditions are as follow:n(1,3-benzenediol):n(ethyl acetoacetate)1.0, Zirconium sulfate tetrahydrate 0.4g,10mL cyclohexane, the reaction time 12 min,microwave radiation power 500W.

Based on the rigid-flexible coupling virtual prototyping technology, the entities model of wheel loaders structural system was established by using Pro/E, then it was imported into the ADAMS environment and constraints were added to create a rigid model, and the corresponding rigid body was replaced by the model neutral file generated by ANSYS, thereby the rigid-flexible coupling virtual prototype was established. The speed and acceleration curve of bucket in a work cycle, the dynamic stress of link and the rear frame was achieved, and the dynamic characteristics of the bucket was analyzed. This paper can provide a reference for similar models of rigid-flexible coupling dynamics simulation.

Based on the previous experiments and theoretical analyses, finite element analyses (FEA) and parametric study on seismic behavior of Cover Plate Strengthen-Beam Flange Weaken Beam-to-Column (CPSBFW) connection are executed by using ABAQUS. Suggestions on design conceptions and details of the cover plate strengthen-beam flange weaken beam-to-column connection are presented in this paper, and that provide valuable reference for design of beam-to-column connections in steel structures.

To automatic test the function and performance of an airborne radar, changeable test adapter is adopted to implement the hardware and software design of the automatic test set of the antenna, transceiver and indicator of the radar based on AT89C52. Problems such as t the different types of interfaces, the various kinds of signals and the test of microwave signal are solved successfully and the objectives of resource sharing and automatic test are realized. The test software is designed by modular structure, and with the help of automatic test set hardware, the required test items of the radar system are experimented and the test process control succeeded. Experiment results show that the automatic test set performs steadily and the results meet the requirements of the airborne radar. The set has the advantages of intelligent, manageable and reducing artificial errors. It provides effective guarantees for radars maintenance, fault diagnosis and fault detection, and has a wide application prospect with low cost.