纳秒脉冲电源驱动提高KrCl^＊准分子灯辐射效率的实验研究

针对目前准分子灯效率偏低的现状,为了从电源角度提高准分子灯紫外辐射的效率,本文对电源驱动类型（正弦/脉冲）以及脉冲电源参数（极性、电压幅值、频率）对介质阻挡放电激发准分子KrCl＊（222nm）紫外辐射的影响进行了实验研究。实验结果表明：脉冲驱动比正弦电压驱动紫外辐射的效率提升86.5%;电源的极性对灯的工作特性没有显著的影响,单向负脉冲效果略好些;随着电源电压幅值的增加,准分子灯紫外辐射强度增加,但紫外辐射效率下降;频率升高,准分子灯紫外辐射强度提高,效率随频率变化不明显。本文还对实验结果作了简要分析和理论解释。     

稀有气体-卤素准分子光源的最新进展

对准分子光源的一般性质进行了介绍,并概述了5种最具应用前景的稀有气体-卤素准分子光源的最新研究进展。目前获得的最佳紫外辐射效率为:溴化氪(KrBr*)207nm,2.4%;氯化氪(KrCl*)222nm,15%;氯化氙(XeCl*)308nm,11%;碘化氙(XeI*)253nm,2%;溴化氙(XeBr*)282nm,10.5%.     

一种单级图腾柱无桥交流发光二极管驱动电源

针对交流发光二极管(AC LED)直接与市电连接存在效率低、谐波含量高以及频闪的问题,提出一种交流发光二极管(AC LED)驱动电源。提出的驱动电源采用单级图腾柱无桥结构,并辅之高频方波驱动策略,具有使用元件少、控制简单的优点。理论分析和实验证明:提出的驱动电源在输入电压10%波动范围内,效率大于90%,功率因素大于0.95,且无任何频闪。     

222 nm准分子光源系统的散热优化

222 nm准分子灯可应用于人机共存的紫外杀菌应用场景，近年来由于新冠疫情爆发而引起了广泛的关注，具有广阔的应用前景。但由于当前准分子光源系统缺乏有效的热管理设计，导致使用时灯管工作温度很高，从而影响了辐射效率。本文采用并联管路的流量分配模型来分析同轴结构准分子灯内外管壁的散热状态，设计制作了一种双风扇漏斗式灯具散热结构，并通过仿真计算和实验测量的方法与通孔式和单风扇式灯具的散热情况进行了比较。与单风扇式灯具相比，双风扇漏斗式灯具能够在保持内外管壁温度基本一致的同时，使外管壁温度降低78℃,从而使灯具的辐照度提高了10.8%。     

安全有效的222nm紫外线杀菌技术

对低压汞灯、脉冲氙灯、222nm准分子灯3种紫外线杀菌方式及其杀菌原理进行介绍。然后对222nm紫外线杀菌技术的研究现状和实际应用进行分析,阐明生活中安全紫外消毒的可行性,最后对222nm紫外线杀菌技术的发展做出展望。     

H.I.D．灯最新启动方法双频同步功能性

灯的冷端温度和灯的功率、结构、形状、环境温度、冷却条件、电源电压的波动等因素有关，大多数的灯都做成圆柱形、直管形，这样可使整个灯的表面温度分布比较均匀，灯的冷端温度就由灯的管壁负载(Ws)所决定，Ws=P／S，P为灯的输入功率(W)，S为灯管的表面积(CM^2)。     

电子镇流器相关专利简介

1一种双频混光式脉宽调节式调光电子镇流器 公开(公告)号:CN101217848 摘要:一种双频混光式脉宽调节式调光电子镇流器,涉及一种电子镇流器.提供一种可保证灯亮度在100%～30%之间可靠调光、不会引起灯闪烁现象且方便应用于单线制照明控制线路、可广泛用于现有的节能灯和镇流器中的双频混光式脉宽调节式调光电子镇流器.设有整流电路、过零检测电路、系统控制电路、双频点功率输出电路和灯驱动电路.整流电路输入端外接供电电源;过零检测电路的输入端接整流电路输出端;系统控制电路输入端接过零检测电路输出端;双频点功率输出电路的电源输入端接整流电路输出端,双频点功率输出电路的控制输入端接系统控制电路;灯驱动电路输入端接双频点功率输出电路输出端,灯驱动电路输出端外接负载.     

222 nm准分子灯、UVC-LED灯、脉冲强光杀菌灯技术、应用、标准现状与发展趋势

杀菌消毒用紫外辐射源是紫外线杀菌消毒技术应用的核心部件。本文介绍了222 nm准分子灯、UVC-LED灯和脉冲强光杀菌灯的技术特性、应用现状、发展趋势与标准现状,为设计者和制造商了解与应用它们提供参考。通过对比分析得知,未来很长一段时间内热阴极紫外线杀菌灯仍会是紫外线杀菌消毒技术应用中核心部件的主体,中压紫外线灯在水处理应用领域是新的发展趋势,222 nm准分子灯会更多应用于温度相对较低环境中的杀菌消毒,UVC-LED灯是未来紫外线消毒技术的发展方向,但是在技术突破方面面临不小挑战,脉冲强光灯多应用于无菌包装和食品的杀菌保鲜。     

一种新型荧光灯控制与驱动电路

提出了一种新型的基于单功率处理级的高功率因数恒功率荧光灯控制及驱动电路;分析了电路工作原理和恒功率条件。功率管驱动信号由PIC16C711单片机产生;恒功率控制由调节电路的工作频率实现。文中给出了灯功率为40W,工作频率为26kHz条件下的实验结果。     

高压快速调Q开关电源的设计

介绍一种高压快速调Q开关电源,设计了以功率MOS管驱动高压电子管为主电路的快速开关,并设计了电源的接口电路、MOS管驱动电路、过流保护电路及高压源稳压电路。实验证明,该电源性能优良且工作稳定。该电源用于YAG激光器的电光调Q时,加在电光晶体KD*P两端的4.1kV高压退压前沿为10ns,在重复频率为3kHz的工作状态下有稳定的输出。     

Bright idea, radio-frequency light sources

The idea of radio frequency (RF) lighting, as well as the first RF lamp patent, appeared long before the first fluorescent and high-pressure lamps came onto the market. It took over a century for the first commercial RF lamp to appear, introducing a new era in the production of light. Progress in semiconductor power switching electronics, along with a more thorough understanding of fundamental processes in RF plasmas, have resulted in commercially viable RF light sources. RF light sources follow the same basic principles of converting electrical power into visible radiation as conventional gas discharge lamps. The fundamental difference between RF lamps and conventional lamps is that RF lamps operate without electrodes (anode and cathode). This has profound consequences on RF lamp characteristics and features. We consider different kinds of RF discharges and their advantages and restrictions for lighting applications. We also describe examples of successful realizations of different kinds of RF lamps     

Measurement of the radial temperature distribution in the central part of an arc burning through a polyethylene tube

The radial temperature distributions in the central part of arcs burning through polyethylene (PE) tubes are estimated by measuring the half-width of Hα line spectrum and using the electron density versus Stark half-width and the electron density versus temperature characteristics. Estimation is carried out for various tube inner diameters (2 and 4 mm) and dc arc currents (5, 10 and 15 A). The result shows that the temperature at the arc center is around 10,000 K, and it tends to increase as the tube inner diameter becomes narrow and/or the arc current increases. The overall temperature distributions from the arc axis to the tube wall are obtained by combining these inner temperature distributions with outer temperature distributions which have been derived from C₂ spectra. They are found to take a form of typical two-temperature distributions of ablation stabilized arcs. The electric field strengths of PE arcs are evaluated from the temperature distributions and the electrical conductivity versus temperature characteristics of thermally decomposed polyethylene vapor gas. The results agree well with experimental values.     

Quantitative research on higher order harmonics in metrology beamline

The synchrotron radiation spectra of the spherical grating monochromator (SGM) working in the soft X-ray and VUV region are often contaminated by significant amounts of higher order harmonics. They cannot be suppressed completely by suitable filters. Higher order contributions in the spectral radiation standard and metrology beamline were researched using transmission grating (made in-house) and IRD AXUV100G (USA) photodiode detector. The exit beam was dispersed with the transmission grating behind the exit slit of the monochromator, and the contributions of the different orders were analyzed. The higher order distributions were quantitatively determined for three gratings with line densities of 1800, 600 and 200 l/mm. Experiment results show that in wavelengths between 5 nm and 15 nm the contributions of the higher orders to the detector signal are restricted to less than 7% even without the use of filters. In wavelength regions between 5 nm and 34 nm, the contributions of the higher orders to the detector signal are less than 14% with proper A1, Si₃N₄ and Zr filters, and after being modified by quantum efficiency of the detector, the higher order contributions are restricted to less than 6.5%. The study also shows that higher orders are almost totally suppressed by MgF₂ filter when the wavelength ranges between 115–140 nm. __________ Translated from Optics and Precision Engineering, 2007, 15(5): 640–645 [译自: 光学精密工程]     

12X18H12T钢管蒸汽侧氧化皮及其剥落物的微观结构与形貌特征

通过对某电厂12X18H12T过热器和再热器割管样品内壁氧化皮及其剥落物进行金相检验、扫描电镜观察、微区能谱分析、X-射线衍射等试验分析,研究和总结了18-8系列粗晶奥氏体不锈钢过热器和再热器蒸汽侧氧化皮的宏观和微观结构与形貌特征。研究结果表明：该不锈钢原生氧化皮通常可分为内、中、外3层氧化物,其内层为结构致密的富铬尖晶石结构氧化物,中间层主要是结构疏松、多孔的Fe3O4,最外层为结构致密但厚度较薄的Fe2O3;剥落物主要是原生氧化皮的外两层铁氧化物,内层氧化物一般并不剥落。原生氧化皮外层剥落部位在后继运行过程中不会再生长出新的Fe3O4类氧化物,但会逐渐生长出新的Fe2O3层,该次生Fe2O3层生长速度十分缓慢。     

亚大气压介质阻挡辉光放电的特性研究

亚大气压强下的均匀辉光放电,有可能成为无汞荧光灯。它在材料表面改性、灭菌等领域也有广阔的应用前景。利用水电极在真空玻璃箱内的亚大气压条件下实现了介质阻挡均匀辉光放电。电流波形与放电均匀性没有必然的关系,周期性出现的单电流脉冲无法作为高频下均匀放电的普适性判据。测量了不同气压下氩放电的发射光谱,发现高气压下由于下能级的吸收增加,氩750～850nm的部分谱线强度反而降低。分析了放电照片的灰度均匀性,认为它可以作为判断均匀放电的定量参数。气压越高,越不容易实现均匀放电。气体的均匀放电的气压上限分别是Ar（760 Torr）,Ar-O2（600 Torr）,N2（525 Torr）,N2-O2（375 Torr）,空气（300 Torr）。电负性的O2和H2O会吸附自由电子,将提惯击穿电压,影响放电的均匀性。     

陶瓷金卤灯电弧管内壁腐蚀综述

本文分析了陶瓷金卤灯工作过程中,陶瓷管内壁的气相腐蚀机理及电弧管中的输运过程.介绍了诊断管壁腐蚀程度的X光成像、扫描电镜和努森泄流质谱等方法,从电弧管结构、金属卤化物组分改进和电极封接等方面总结了减少陶瓷管壁腐蚀的措施.     

GIS盆式绝缘子金属外圈及屏蔽内环设计的必要性

笔者以GIS电场分布、局部放电超高频电磁波的辐射及测量以及盆式绝缘子强度与电性能等3方面分析,对盆式绝缘子带金属外圈和屏蔽内环的设计提出质疑,并提出了GIS盆式绝缘子合理的结构设计要求。     

微波等离子灯可见光辐射的研究

微波等离子灯具有的类似太阳光的连续光谱是其他灯所不能比拟的优点。本文首先探讨和研究了微波等离子灯的光效测定及所得出的结论,然后从可见光辐射功率这个新角度进行了分析。重点说明了微波等离子灯的能量损失,并结合视觉函数在微波等离子灯测试时对人眼存在误差而提出需要对该种灯的光效计算方法进行修正,最后总结了使光效的改进的设想和方法,这对该新型绿色光源进一步开发具有实用意义.     

An integrated tube cleaning system

A modern and efficient method for removing deposits from the inner surfaces of tubes used in heat-transfer equipment operating at thermal and nuclear power stations is considered. This method is intended primarily for cleaning steam-turbine condensers, delivery-water heaters, and gas- and oil coolers with thin-walled tubes made of nickel-copper alloys or brass 19–28 mm in diameter, with a 1-mm thick wall, and 5–11 m long.