Space Vector Pulse Width Modulation (SVPWM) technique is one of the best method of PWM variable frequency drive and make the AC motor achieving the performance as good as DC motor.Permanent Magnet Synchronous Motor (PMSM) has many advantages of small volume,steady operation,high energy efficiency,large output torque,etc.To solve the problems of auto environment and energy sources,study on Pure Electric Vehicles (PEV) driven by PMSM based on SVPWM is an important research direction and has the practical value.On the basis of analyzing the basic models of SVPWM,PMSM and PEV,simulation model of PMSM Control System for PEV can be constructed.The results of the simulation show that the control system has super performance and meet the request of system.

关键词：空间矢量脉宽调制（SVPWM）；永磁同步电机（PMSM）；纯电动汽车（PEV）；模拟

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The partial substitution of Zr for La has been performed in order to ameliorate the electrochemical hydrogen storage performances of La-Mg-Ni based A2B7-type electrode alloys.The melt spinning technology was used to prepare the La0.75-xZrxMg0.25Ni3.2Co0.2Al0.1 (x=0,0.05,0.1,0.15,0.2) electrode alloys.The impacts of the melt spinning and the substituting La with Zr on the structures and the electrochemical hydrogen storage characteristics of the alloys were systemically investigated.The analysis of XRD and TEM reveals that the as-cast and spun alloys have a multiphase structure,composing of two main phases (La,Mg)2Ni7 and LaNi5 as well as a residual phase LaNi2.The electrochemical measurement indicates that both the substitution of Zr for La and the melt spinning ameliorate the electrochemical cycle stability of the alloys dramatically.Furthermore,the high rate discharge ability (HRD) of the as-spun (10 m/s) alloys notably declines with growing the amount of Zr substitution,while it first augments and then falls for the (x=0.1) alloy with rising the spinning rate.

关键词：A2B7型合金;代拉与锆，熔融纺丝;电化学特性

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Conventional storage of large amounts of hydrogen in its molecular form is difficult and expensive because it requires employing either extremely high pressure gas or very low temperature liquid. Because of the importance of hydrogen as a fuel, the DOE has set system targets for hydrogen storage of gravimetric (5.5 wt) and volumetric (40 g L-1) densities to be achieved by 2015. Given that these are system goals, a practical material will need to have higher capacity when the weight of the tank and associated cooling or regeneration system is considered. The size and weight of these components will vary substantially depending on whether the material operates by a chemisorption or physisorption mechanism. In the latter case, metal-organic frameworks (MOFs) have recently been identified as promising adsorbents for hydrogen storage, although little data is available for their sorption behavior. This grant was focused on the study of MOFs with these specific objectives. (1) To examine the effects of functionalization, catenation, and variation of the metal oxide and organic linkers on the low-pressure hydrogen adsorption properties of MOFs. (2) To develop a strategy for producing MOFs with high surface area and porosity to reduce the dead space and increase the hydrogen storage capacity per unit volume. (3) To functionalize MOFs by post synthetic functionalization with metals to improve the adsorption enthalpy of hydrogen for the room temperature hydrogen storage. This effort demonstrated the importance of open metal sites to improve the adsorption enthalpy by the systematic study, and this is also the origin of the new strategy, which termed isoreticular functionalization and metalation. However, a large pore volume is still a prerequisite feature. Based on our principle to design highly porous MOFs, guest-free MOFs with ultrahigh porosity have been experimentally synthesized. MOF-210, whose BET surface area is 6240 m2 g-1 (the highest among porous solids), takes up 15 wtof total H2 uptake at 80 bar and 77 K. More importantly, the total H2 uptake by MOF-210 was 2.7 wtat 80 bar and 298 K, which is the highest number reported for physisorptive materials.

关键词：储氢；吸附剂；化学吸附；孔隙度；焓

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The broad research objective of the overall project was the development of multi-scale optimization approaches to aid in the design of energy storage systems. More specically, we focused on the development of optimization methods that operate on different physical length-scales for optimizing the internal structure of nanoporous materials. Potential applications include electrical supercapacitors and hydrogen storage systems. The optimization algorithms we have developed can be applied to more general hierarchical design problems arising from the design of complex systems.

关键词：储能系统;多孔材料;算法;电容;无孔的材料

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This work is directed towards the preparation of chemoselective ruthenium catalyst.The catalyst is a new type of ruthenium(Ⅱ) complexes supported on γ-Al2O3,which have ruthenium(Ⅱ) centers coordinated to the ligands triphenylphosphine and (1 S,2S)-1,2-Diphenyl-1,2-ethanediamine.The catalyst for the selective hydrogenation of ketones in the mild conditions is investigated.The results show that the performance of the catalystis greatly influenced by the ratio of Ru and PPh3 and reduction time,respectively.

关键词：加氢；化学选择性；钌；酮类

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Verilog is the most widely used hardware description language.It can be used in the modeling,synthesis,and simulation stages of the hardware system designing.This thesis is about applying Verilog HDL to design the multifunctional electronic timing system.This system has brought about the timing function,the Alarm clock function,the time checking module,the stop clock module,the exact hour alarming module,the alarm clock's shielding and alarming function module and the stop clock Prompting function module.The modules which have applied this design can be transplanted to other kinds of electronic control systems conveniently.This system uses the Verilog HDL to design,so it has nothing to do with the craft.It allows us to attain the applicable actual circuit easily without considering much about the details of the gate level and the realization of the craft in the function designing stage and the logic verification stage.We just need to exert different conditions according to the demand of the design of the system.

关键词：Verilog HDL语言;多种功能;硬件描述语言

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Traditional methods for crack distress detection cannot capture the geometric information of images and tend to amplify noise.In order to solve this problem,an improved algorithm based on contourlet transform and multi-direction morphological structuring elements is proposed.The new algorithm decomposed image into approximation coefficients and detail coefficients. Morphological erode operations is used to distinguish noise form detail information according to dependencies of contourlet coefficients,then nonlinear mapping function is used to modify the contourlet coefficients.And the enhanced image is obtained by contourlet inverse transform.Compared with other traditional methods,the experimental results indicate that our method can effectively extract the edges of cracks and evidently decrease the influence of noises.Moreover,it can provide good image processing speed.

关键词：图像增强；contourlet变换；数学形态学；多方向结构元素成分

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A prototype of video detection system applied to traffic flow inspection is developed,which uses CMOS linear image sensor with high resolution 2K pixels and wide dynamic range as the core of imaging device.It combines FPGA with DSP as the core of acquisition and processing of massive image data.Moreover,a novel multiscale and hierarchical clustering algorithm for image segmentation is presented.Based on the theory of graph spectral,the algorithm can construct a new graph by analyzing the feature of an original image at different clustering scales,so that image (gmentation) can be accomplished easily to segment the image.The simulation results show that the (scan) speed of this system can reach to 1000 lines per second,the resolution being 2048 pixels.

关键词：电控；视频检测; CMOS线图像传感器; DSP

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A simple anaerobic biodegradation process using wastewater treatment plant (WWTP) effluent, shredded paper, and a purge of nitrogen gas was used to produce hydrogen and simultaneously capture nitrogen and phosphorus. Two reactor configurations a sequencing batch reactor (SBR) and a classic batch reactor (CBR) were tested as simultaneous saccharification and fermentation reactors (enzymatic hydrolysis and fermentation in one tank). The CBR demonstrated greater stability of hydrogen production and simplicity of operation, while the SBR provided better nitrogen and phosphorus removal efficiencies. Nuclear magnetic resonance analyses showed acetic acid to be the main product from both reactors. Optimal CBR conditions were found to be pH 5, 4 g/L loading 0.45 ml/g Accellerase 1500, and 38 C. Experiments with an argon purge in place of nitrogen and with ammonium chloride spiking suggested that hydrogenase and nitrogenase enzymes contributed similarly to hydrogen production in the cultures. Analysis of a single fermentation showed that hydrogen production occurred relatively early in the course of TOC removal, and that follow-on treatments might extract more energy from the products.

关键词：制氢；铵化合物；冰醋酸；生物降解

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Develop and demonstrate reversible nanostructured activated carbon hydrogen storage material which has at least a 5.5 wtmaterial-based gravimetric capacity and a 40 gH2/L material-based volumetric capacity at-38-85C, and the potential to meet DOE 2017 system-level targets. Prepare and characterize nanostructured polymer derivatives as carbon precursors. Initiate the production of nanostructured activated carbon for hydrogen storage. Develop methods for sorbent-based doped polymer/carbon.

关键词：储氢;活性炭;纳米结构聚合物;吸附剂

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