多功能半导体激光医疗仪电源的研制

根据“多功能半导体激光医疗仪”整机的要求,采用同一电源对667nm和808nm半导体激光器实施供电。为避免电源在开、关机时对半导体激光管产生浪涌冲击,电源在设计中采用了适当的逻辑功能。并可保证对667nm激光器供电时,即使打开808nm激光器供电开关,也不对808nm半导体激光器供电,反之亦然。电源设有手动、计算机两种控制方法,及恒定功率、电流两种工作方式。     

高性能IGBT模块的设计考虑

本文对ＩＧＢＴ模块中功率芯片（ＩＧＢＴ和续流二极管）的优化设计进行了讨论。通过优化几个重要的工艺参数并改进器件的结构，ＩＧＢＴ不仅有足够的短路容量，而且正向压降与电流下降时间之间可实现最佳折衷。另外，续流二极管的反向恢复特性也有明显改善。通过采用衬底控制技术，ＩＧＢＴ模块的输出特性不受温度的影响，输出电流更稳，输出阻抗更高。本文详细介绍了整个设计考虑。     

具有大电流输出能力的开关电源

本文介绍大电流输出的开关电源芯片MAX1623的特点，设计原理和典型应用电路。     

N个振荡器相互注入锁定同步振荡系统

本文对Ｎ个振荡器相互注入锁定同步振荡系统提出了一种通用的分析方法。建立了该系统的完整非线性等效模型，导出了系统的状态方程。对于各种不同电路形式的振荡系统，只要将具体的电路参数代入，就可计算其输出功率，功率合成效率及工作频率等参数，从而使这类系统的计算机辅助分析和设计成为可能。     

功率管焊接质量射线检测

介绍采用射线方法检测功率管芯片与基座之间的焊接质量。试验证明，选用合适的透照参数可使X射线照相和X射线实时成像对焊接部位的检测均得到较高的对比灵敏度，但X射线照相法成本低廉，一次可透照多个工件，效率高，为该功率管焊接质量的理想检测方法。     

分流液压转向牵引计算的展开图及其应用

本文论及分流液压转向牵引计算的概念,方法及其展开图,并且提供了计算机绘制的展开图和应用实例。     

An analytical expression for the power coefficient of an ideal horizontal-axis wind turbine

The paper shows that an analytical evaluation of the power coefficient C_p for an ideal horizontal-axis wind turbine can be made via an expression giving the direct relationship of C_p and the axial induction factor a. The results obtained agree closely with those obtained numerically from the usual integral expression involving several variables.     

A novel nickel-based mixed rare-earth oxide/activated carbon supercapacitor using room temperature ionic liquid electrolyte

Mesopore nickel-based mixed rare-earth oxide (NMRO) and activated carbon (AC) with rich oxygen-contained groups were prepared as electrode materials in a supercapacitor using room temperature ionic liquid (RTIL) electrolyte. These electrode materials were characterized by XPS, XRD, N₂ adsorption, SEM as well as various electrochemical techniques, and showed good properties and operated well with RTIL electrolyte. A 3 V asymmetrical supercapacitor was fabricated, which delivered a real power density of 458 W kg⁻¹ as well as a real energy density of 50 Wh kg⁻¹, and during a 500-cycle galvanostatic charge/discharge measurement, no capacity decay was visible. Such promising energy-storage performance was to a large extent ascribed to nonvolatile RTIL electrolyte with wide electrochemical windows and high stable abilities worked with both electrode materials.     

集成电路芯片级的热分析方法

文章在研究分析了集成电路中功耗的主要来源以及温度对集成电路性能的影响后，详细总结了近年来集成电路芯片级的几种热分析方法。并从实际应用角度对这几种方法进行了分析和比较，讨论了各个方法的优点及其适用范围。