面向制造业的可重构进销存管理系统设计

论文介绍了基于Web的组件化可重构进销存管理系统，从建模方法、体系结构和组件技术等角度描述了系统设计思想，并进一步阐述了系统涉及的组件分类、组件粒度分析以及XML技术的应用等主要设计技术，最后提出了进销存管理系统今后的研究方向。     

Effect of heat treatment on microstructure and interface of SiC particle reinforced 2124 Al matrix composite

The microstructure and interface between metal matrix and ceramic reinforcement of a composite play an important role in improving its properties. In the present investigation, the interface and intermetallic compound present in the samples were characterized to understand structural stability at an elevated temperature. Aluminum based 2124 alloy with 10 wt.% silicon carbide (SiC) particle reinforced composite was prepared through vortex method and the solid ingot was deformed by hot rolling for better particle distribution. Heat treatment of the composite was carried out at 575 °C with varying holding time from 1 to 48 h followed by water quenching. In this study, the microstructure and interface of the SiC particle reinforced Al based composites have been studied using optical microscopy, scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectroscopy (EDS), electron probe micro-analyzer (EPMA) associated with wavelength dispersive spectroscopy (WDS) and transmission electron microscopy (TEM) to identify the precipitate and intermetallic phases that are formed during heat treatment. The SiC particles are uniformly distributed in the aluminum matrix. The microstructure analyses of Al–SiC composite after heat treatment reveal that a wide range of dispersed phases are formed at grain boundary and surrounding the SiC particles. The energy dispersive X-ray spectroscopy and wavelength dispersive spectroscopy analyses confirm that finely dispersed phases are CuAl₂ and CuMgAl₂ intermetallic and large spherical phases are Fe₂SiAl₈ or Al₁₅(Fe,Mn)₃Si. It is also observed that a continuous layer enriched with Cu and Mg of thickness 50–80 nm is formed at the interface in between Al and SiC particles. EDS analysis also confirms that Cu and Mg are segregated at the interface of the composite while no carbide is identified at the interface.     

White polymer phosphorescent light-emitting devices with a new yellow-emitting iridium complex doped into polyfluorene

A new yellow-emitting iridium complex Ir(3-piq)₂pt with 3-phenylisoquinoline(3-piq) as cyclometalated ligand by introducing 2-(2H-1,2,4-triazol-3-yl)pyridine (pt) as ancillary ligand was synthesized. Efficient yellow polymer light-emitting devices (PLEDs) with the new iridium complex Ir(3-piq)₂pt in device structure ITO/PEDOT/PVK/Ir-complex (x%):PFO (or +PBD (30%))/Ba/Al (with or without PBD electron transports additive) were fabricated. The device doped with 4% Ir(3-piq)₂pt displayed a quantum efficiency of 9.4% (16.2 cd/A) at 5.06 mA/cm² with PBD additive. A white emission was also obtained at a doping concentration of 0.5% Ir(3-piq)₂pt with no PBD added. CIE coordinate (0.34 and 0.31) close to National Television Standards Committee (NTSC) white standard, external quantum efficiency of 2.25%, and luminance of 2250 cd/m² at applied voltage of 15 V were obtained. The results indicated that introducing triazole group based ancillary ligand into iridium complexes could enhance the electron-transporting ability of the iridium complexes.     

A first-principles study on the structural stability of Al2Ca Al4Ca and Mg2Ca phases

Energetics and electronic structures have been determined from first-principles calculations for Al₂Ca Al₄Ca Mg₂Ca phases. These calculations show that Al₂Ca phase has the strongest alloying ability as well as the highest structural stability, next Al₄Ca, finally Mg₂Ca, which is also well explained through the densities of states (DOS) of these compounds.     

Effect of remelting process on characterization of air-plasma sprayed Fe67.5Ni23.5B9 alloy coatings onto 1Cr18Ni9Ti stainless steel

To develop a composite material with good mechanical and radiation shielding properties, the Fe–Ni–B (Fe_67.5Ni_23.5B₉, wt. %) coatings onto ₁Cr₁₈Ni₉Ti stainless steel substrate (SS, same as below) were prepared using air-plasma spraying (APS) technique in this work. A remelting process (1050 °C/2 h) was performed on the Fe–Ni–B coatings laminated composite under vacuum condition. The microstructure, phase composing, adhesion strength, Vickers hardness distribution and residual stress of Fe–Ni–B coatings before and after the remelting process were contrastively characterized. The results show that the remelting process decrease the coating defects and make the coating more cohesive and stable. The element diffusion and new compounds formation within the coating and interface area improves the adhesion and thermal fatigue of Fe–Ni–B coatings. In addition, the drop of variability of Vickers hardness data and residual stress level qualitatively identify that the Fe–Ni–B coatings possess more consistent microstructure and mechanical integrity after the remelting process.     

电动汽车用飞轮电池充放电控制系统研究

针对现有电池技术还不能满足电动汽车对电池系统能量密度和功率密度还有寿命的要求,本文结合蓄电池的高比能量和飞轮电池的高比功率,提出了基于蓄电池和飞轮电池的复合电源。建立了飞轮电池的充放电的数学模型,并提出了飞轮电池充放电的控制策略。飞轮充电过程中采用模糊-PI复合控制策略,放电过程中根据驱动电机需要的瞬时电流值来控制斩波器开关的通断。结果表明系统具有较好的动态特性。     

热源式红外目标运动模拟器测控系统设计

根据所研制的红外目标运动模拟器的测控需求,设计了基于单片机C8051F020的测控系统.测控系统的硬件和软件结构均采用标准化、模块化的设计思想,系统具备可扩展、可裁减的能力.采用增量式PID温度控制算法实现红外目标的发热温度控制,达到了控制精度的要求.实践证明:设计的模拟器测控系统运行稳定、可靠,满足各项测控指标.     

基于三视图的几何重构B-rep算法研究

在讨论保证输出形体与输入视图一致的条件(线段的合法条件)的基础上,改进了确定性面序列判别法.基于线段的合法条件和确定性面序列的性质,提出了视图中的边(2D边)的分类及判别方法,并讨论了2D边与属于输出形体的候选边的对应关系.这些工作可避免几何元素分层构建法(即B-rep法)在有些情况下重构失败或丢失合法输出形体,从而提高了B-rep法的鲁棒性和重构结果的准确性.     

Effects of power ultrasonic treatment on microstructure and mechanical properties of T10 steel

The microstructure and mechanical properties of T10 steel treated with power ultrasonic during solidification are investigated. A self-developed experimental setup is built for the propagation of ultrasonic vibration into the melt along the horizontal direction. Experimental results indicate that the power ultrasonic applied in the melt can not only refine the microstructure remarkably but also enhance both tensile strength and ductility values of T10 steel. Furthermore, the finer grains can be obtained due to the higher incident ultrasonic power. SEM fractographs show that the sample with 600 W ultrasonic treatment exhibits a ductile fracture surface covered with deformation dimples, while the sample without ultrasonic treatment shows a brittle fracture surface. The effects of power ultrasonic on the melt are discussed.     

滑阀真空泵振动平衡的优化设计研究

滑阀真空泵在许多行业得到广泛应用。但滑阀真空泵的振动平衡问题一直是国际上未解决的技术难点。本文建立了滑阀真空泵动态仿真模型,并以改变内置平衡块的结构来改变各构件重心位置的方式进行了动态仿真,探讨了滑阀真空泵的优化设计问题。仿真测试结果表明,通过调整泵的内部结构可以明显地改善滑阀泵惯性力引起的振动。