光控太阳能装饰灯的设计与实现

太阳能光伏能够提供较为稳定的直流电源,是目前最受欢迎的绿色能源之一;而LED(发光二极管)则是直流电控制光源,两者的结合已有诸多研究。本文设计了一款单片机控制和光自动控制相结合的太阳能装饰灯,集美观、实用、节能等理念于一体。     

Improving performance of high-power indium gallium nitride/gallium nitride-based vertical light-emitting diodes by employing simple n-type electrode pattern

In this work, simple n-type electrode structures were used to enhance the electrical and optical performances of fully packaged commercially mass-produced vertical-geometry light-emitting diodes (VLEDs). The forward bias voltage of the VLED with a Y-pattern electrode increased less rapidly than that of VLEDs with a reference electrode. The VLEDs with the reference and Y-pattern electrodes exhibited forward voltages of 2.93±0.015 and 2.89±0.015 V at 350 mA and 3.77±0.015 and 3.53±0.015 V at 2000 mA, respectively. The VLEDs with the Y-pattern electrode resulted in a higher light output than the VLEDs with the reference electrode with increase in the drive current to 2000 mA. The emission images showed that the VLEDs with the Y-pattern electrode exhibited better current spreading behavior and lower junction temperatures than the VLEDs with the reference electrode. With increase in the current from 350 to 2000 mA, the VLEDs with the Y-pattern electrode experienced a 39.4% reduction in the wall plug efficiency, whereas the VLEDs with the reference electrode suffered from a 43.3% reduction.     

Naphthalimide‐phthalimide derivative based photoinitiating systems for polymerization reactions under blue lights

Naphthalimide‐phthalimide derivatives (NDPDs) have been synthesized and combined with an iodonium salt, N‐vinylcarbazole, amine or 2,4,6‐tris(trichloromethyl)‐1,3,5‐triazine to produce reactive species (i.e., radicals and cations). These generated reactive species are capable of initiating the cationic polymerization of epoxides and/or the radical polymerization of acrylates upon exposure to very soft polychromatic visible lights or blue lights. Compared with the well‐known camphorquinone based systems used as references, the novel NDPD based combinations employed here demonstrate clearly higher efficiencies for the cationic polymerization of epoxides under air as well as the radical polymerization of acrylates. Remarkably, one of the NDPDs (i.e., NDPD2) based systems is characterized by an outstanding reactivity. The structure/reactivity/efficiency relationships of the investigated NDPDs were studied by fluorescence, cyclic voltammetry, laser flash photolysis, electron spin resonance spin trapping, and steady state photolysis techniques. The key parameters for their reactivity are provided. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 665–674     

双频抽运提高SBS相位共轭保真度

相位共轭保真度是相位共轭镜技术用于强激光系统中的一个重要指标。采用四波混频加强SBS的方法 ,其相干拍频驱动声子场 ,能提高SBS相位共轭保真度。对于双频单池结构 ,使用列阵相机测量激光束能量远场角分布 ,在SBS转换效率最佳时 ,对相干驱动SBS相位共轭保真度进行了实验研究     

用于有源电力滤波器的IGBT驱动及保护研究

介绍有源电力滤波器设计中EXB841型绝缘栅场效应晶体管(IGBT)驱动器的驱动原理和电路特点,对IGBT的栅极驱动特性、栅极串联电阻进行了探讨,给出过流保护和过压吸收的有效办法。样机试运行证明此种设计方案可靠、有效。     

交通诱导室外LED显示屏有关问题之浅见

本文探讨了智能交通系统中交通诱导室外LED显示屏的使用功能,对交通诱导室外LED显示屏在实际应用中的有关问题发表了认识和看法。     

美国固体照明技术进展概况

介绍了美国能源部于2002年开始实施的固体照明(SSL)技术的"下一代照明计划".同时对美国SSL技术的研发、生产和使用现状以及召开学术会议的情况做了叙述.     

硅微机械梳齿静电谐振器的建模与分析

基于参数化的计算机辅助设计（CAD）软件，对硅微机械梳齿静电谐振器进行了实体建模，以有限元分析软件为工具，进行了谐振器的模态分析，静态分析和谐响应分析，初步揭示了谐振器的静、动态特性，有助于改善设计效率和质量，展示了计算机辅助工程（CAE）技术在微机电系统（MEMS）研究中的重要作用。     

基于通信的港口管理系统的研究

讨论了如何利用Access7.0设计包含有通信的管理信息系统，并结合生产管理系统的实例。利用微软公司的Visual Basic中包含的通信控件，实现Windows95环境下通信程序的设计方法，介绍了通信控件的属性以及使用方法，给出了基本的通信程序。     

Graded Heterojunction of AIGalnP High-brightness Light Emitting Diodes

A simple model of the graded heterojunction in AIGalnP compound semiconductors was introduced to analyze the band profile. The band profiles are analyzed with the different grading ways but the same grading length and under the different doping densities. The effect of the different grading lengths on the surplus of the potential of the spike to the potential of N region are also analyzed under the different doping densities. Through the experiments, it proves that the performances of high brightness light emitting diodes can be improved by the effects of the graded heterojunction.