塑料光纤及其放大器的研究

研究了塑料光纤从材料合成到光纤成丝的整个工艺过程。探讨聚合方式对塑料光纤光性能的影响。研究聚甲基丙烯酸甲酯及苯乙烯 -甲基丙烯酸甲酯共聚物材料作为纤芯的塑料光纤。采用新颖的引发剂含氟自由基合成塑料光纤的原料。使用各种包层涂覆工艺涂覆塑料光纤的包层 ,并将紫外光聚合工艺应用到 POF的包层涂覆中 ,从而获得性能优异的塑料光纤。用有机染料掺杂塑料光纤 ,得到具有光放大作用的连续波塑料光纤放大器     

南京工业大学利用鱼明胶成功制备高性能环保的柔性发光器件

正近几十年来,各种交流电致发光(ACEL)器件,特别是柔性器件在平板显示、大型装饰、标志显示照明、光信号等领域得到了发展和应用。在ACEL器件中,通常采用透明塑料制作基底,然而塑料无法降解可能造成严重的环境污染。近日,南京工业大学先进材料研究院黄维院士、于海东和刘举庆教授团队研制出一种基于透明鱼明胶(FG)薄膜的柔性瞬态ACEL器件。这种鱼明胶薄膜以鱼鳞为原料,具有可持续性、经济、环保优点。FG薄膜可以在60℃下几秒钟内溶于水中,在土壤中     

高压断路器喷口材料的试验研究

在分析高压SF6 断路器开断大电流时 ,电弧对喷口烧蚀机理的基础上 ,进行了喷口材料改性试验研究。得出聚四氟乙烯中加入MoS2 ,BN ,光致蓄光材料 (PL) ,复合聚四氟乙烯的介电性能、光学性能、耐电弧烧蚀性能和线膨胀系数的变化规律。研究结果为提高喷口的耐电弧烧蚀性能、改善喷口材料的介电性能和工艺性提供了理论依据。     

结构材料对LED日光灯及LED球泡灯光热性能的影响

通过实验研究,对比分析了当前市场上的典型LED日光灯和LED球泡灯的光热性能。全玻璃结构LED日光灯在光度量参数上表现最好,全塑料结构LED日光灯的颜色坐标稳定性最好。不同的芯片排布方式影响LED球泡灯的光度量和颜色坐标稳定性。对比分析了不同散热材料对LED日光灯和LED球泡灯散热性能的影响,为散热材料的选用提供依据。     

塑料材料在断路器应用中的性能要求探讨

以低压断路器壳体为例,对塑料材料应用于断路器的性能进行探讨。通过对断路器进行短路试验和耐燃试验,分析外壳在试验中所体现的耐压、耐高温、耐燃性能,并提出建议,优化塑料材料在电器产品中的应用,提高断路器的性能。     

微膨胀耐火可塑料的性能与应用

电力建设研究所研制了微膨胀耐火可塑料，随后在此基础上又研制了快硬微膨胀耐火可塑料。这２种材料在炉墙保温工程中被广泛应用，性能稳定，效果明显，无超温和大面积积灰现象，无裂纹和变菜强度和其他性能符合规范要求。微膨胀耐火可塑料的缺点是硬化时间长，材料易结块化；快微膨胀耐火可塑料弥补了前者的不足，性能更好，可推广使用。     

拜耳色彩浸渍技术

被称为Aura色彩浸渍技术的塑料着色工艺，属于拜耳Fantasia项色彩技术之一，可以在单个乃至批量的聚碳酸酯材料部件上应用。通常我们常见的塑料着色工艺都是对聚碳酸酯母粒进行批量着色．然后再加工成各种用品。用户往往采购配好颜色的母粒进行生产，也就是说．只能是大批量生产．很难对独特颜色的产品进行少量甚至单个的加工操作。但Aura解决了这个难题，用户可先将透明、半透明或不透明的树脂如模克隆聚碳酸酯或者拜本兰聚碳酸酯混合物加工成型．然后通过Aura染色工艺将颜色直接注入已成型的部件。这意味着定制的注塑或者挤塑产品可以根据客户要求在其自己的设施内进行色彩染制。     

塑料件的结构与模塑成型的关系

一 引言 随着我国四化的发展,塑料行业是大有前途的,有专家估计到公元2000年塑料产量将占世界所有原材料的80％,钢铁将退居第二位。电器行业工程塑料的应用也是很乐观的。我厂进入80年代以来塑料件增长约为70年代末的一倍。提高了继电器绝缘性能,减轻了重量和增加了美观程度,塑料已广乏应用在绝缘件、结构件、接插件、透明件和装饰件上。由于塑料广乏应用,有必要对塑料件结构工艺性,进行分析研究,促使设计与制造工艺统一起来。     

工艺参数对注射成型铁氧体塑料粘结磁体性能的影响

采用尼龙作为粘结剂,与锶铁氧体磁粉和添加剂经过双螺杆挤出机加热混炼,并注射成型得到塑料粘结磁体,研究了含粉量、配方体系、模具磁路设计和取向励磁电流对磁体性能的影响。结果表明,提高含粉量使得塑料粘结磁体密度变大,表面磁通密度、Br和(BH)max呈显著上升趋势,但是磁粉之间摩擦增大导致Hcj和机械强度呈下降趋势。通过配方调整可以改善材料的磁性能和机械性能,制备不同性能的磁体,改变励磁电流亦可调节磁体表面磁通密度(表面场强)。在磁路模拟的基础上对模具进行优化设计,采用表面场强均匀的模具设计方案制备了模具,实验结果与模拟结果一致,得到了两面场强均匀的塑料粘结磁体。     

CG系列光电半导体器件绝缘封装材料

1.发展前景及方向透明绝缘封装材料的研制与开发,是专为光电子技术的发展服务的,其生产水平和材料性能直接影响到光电子元器件的设计和生产。因此,光电子元器件的市场同时也是封装材料的市场。需要使用透明绝缘封装材料的光电子元器件主要包括LED、数码显示板、光电变换元件、光纤相关元器件等。近年来光电子器件在世界各主要经济大国中的生产和销售量都有明显的上升,这可     

Multilayer (Al,Ga)N structures for solar-blind detection

We report on solar-blind metal-semiconductor-metal (MSM) detectors fabricated on stacks of (Al,Ga)N layers with different Al mole fraction. These structures were grown by molecular beam epitaxy on sapphire substrates to allow backside illumination and a low-temperature GaN buffer layer. They consist of a 0.3-0.4-/spl mu/m active layer grown on a thick (Al,Ga)N window layer (/spl ap/1 /spl mu/m) that is transparent at the wavelength of interest. Different Al contents were used in the window layer. We observed that, in general, samples with a high Al content were cracked, which is explained in terms of mechanical strain. MSM photodetectors fabricated on these samples showed large leakage currents that were correlated with the crack density. In order to reduce the strain and eliminate the cracks, we inserted an AlN layer between the buffer and window layer. A crack-free sample was obtained and the solar-blind photodetector fabricated on this structure showed record performance.     

Generation of coherent, femtosecond, X-ray pulses in the“water window”

We report experimental and theoretical results on high-harmonic generation with 25-fs laser excitation pulses. The shortest wavelength we observe, at 2.7 nm, is well within the “water window” region of X-ray transmission. In the case of all the noble gases, we obtain excellent agreement between theoretical predictions for the highest harmonic photon energy generated and our experimental observations. We also obtain excellent agreement between theory and experiment for the highest photon energy generated as a function of laser pulsewidth between 25 and 100 fs. Finally, we observe that the individual harmonic peaks near the cutoff are well resolved for positively chirped pump pulses, but are unresolved in the case of negatively chirped excitation pulses     

基于宽频功率测量系统的高压电机能效计量检测平台设计

当前设计的高压电机能效计量检测平台的检测耗时较长,存在效率低和检测准确率较差的问题,因此提出基于宽频功率测量系统的高压电机能效计量检测平台设计。硬件部分设计了绝缘电阻信号采集模块、温度信号采集模块和局部放电信号采集模块,通过继电器开关控制继电器的闭合,避免了电流换向带来的测量误差,提高了电阻检测精度。在软件设计中实现了登陆窗口功能、管理员功能、历史数据查询功能、状态显示功能和报警功能。计算输入信息参数,采用宽频功率系统及开关滤波器组实现基波与谐波的分开测量,得到输出参数,实现高压电机能效的计量和检测。实验结果表明,所提方法设计的检测平台的检测耗时较短、检测结果准确率高,具有一定的实际应用性。     

High efficiency a-Si//poly-Si tandem solar cell

A series of experimental trials has been carried out to realize the high efficiency a-Si//Poly-Si tandem solar cell. Employing p-type μc-SiC as a wide-gap heterojunction window, a-SiC as an interface buffer layer and n-type μc-Si as a back ohmic contact layer, 17.2 percent conversion efficiency has been achieved with the structure of ITO/p μc-SiC/n Poly-Si/n μc-Si heterojunction. Utilizing an optically transparent a-Si p-i-n cell as a top cell and inserting an optical coupler between the top and the Poly-Si bottom cell, a high total efficiency of 21.0 percent has been obtained so far on the four-terminal tandem cell. This conversion efficiency value represents a world record for a-Si basis tandem solar cells.     

A screen magnifier using "high level" implementation techniques.

This paper presents the architecture of, and the techniques used to build, a screen magnifier for visually impaired people that uses the "high-level" features of the Microsoft Windows operating system. The magnifier uses information from the Desktop Window as its source and overlays this with a topmost, transparent, layered window that contains the magnified image. Issues concerning cursor enlargement, tooltip suppression, and focus tracking are discussed. A stable magnifier results that does not need to use the "dirty" low-level techniques that are typically used to build screen magnifiers. The only known problem of the magnifier is that it fails to suppress the original, unmagnified cursor of the few applications that use custom cursors.     

A Screen Magnifier Using “High Level” Implementation Techniques

This paper presents the architecture of, and the techniques used to build, a screen magnifier for visually impaired people that uses the "high-level" features of the Microsoft Windows operating system. The magnifier uses information from the Desktop Window as its source and overlays this with a topmost, transparent, layered window that contains the magnified image. Issues concerning cursor enlargement, tooltip suppression, and focus tracking are discussed. A stable magnifier results that does not need to use the "dirty" low-level techniques that are typically used to build screen magnifiers. The only known problem of the magnifier is that it fails to suppress the original, unmagnified cursor of the few applications that use custom cursors     

有机混合电液及对Li_xCoO_2材料性能的影响

在锂离子蓄电池研究中,为寻找合适的电液,进行了有机混合电液的研究。关于这方面的资料国内外报道很少,尤其分解电位的数据报道更少,我们根据工作的需要开展了这方面工作。通过对各种溶质、溶剂不同配比组成的各种有机混合电液进行粘度、导电率、电化学窗口的测定及ＬｉｘＣｏＯ２在部分电液中溶解分析,并进行了电性能比较,结果表明：相同溶质不同混合溶剂组成的电液,它们的粘度、电导率及电化学窗口不同;不同溶质相同的混合溶剂组成的电液,它们的粘度、电导率及电化学窗口也不同;不同的电液对ＬｉｘＣｏＯ２阴极充放电行为有明显的影响     

Removal of volatile organic compounds in water using low-energyelectron beam

This paper presents the experimental results concerning removal of organic contaminants in water using low energy electron beam radiation. A laboratory scale apparatus for electron beam irradiation of water is described. The absorbed dose of radiation was controlled by water circulation time (1 to 10 min), accelerating voltage (100 to 170 kV), and electron beam current (0.5 to 1.2 mA) for a constant flow rate of 2 kg/min. The volume of the treated water was 1 dm³. The electron beam was generated in vacuum (p<10^-5 Pa), and electrons were injected into the water through the electron transparent window made of titanium foil with a thickness of 25 μm TCE (trichloroethylene) and chloroform dissolved in deionized water were used in the experiment. The dependency of the relative concentration c=C/C₀; where C is the weight content of compound after electron irradiation and C₀ the initial contaminant concentration, on radiation energy density and the absorbed dose are presented. Although the initial contents of the compounds were higher than those occurring in real water sources, it has been found that it is possible to decompose both of the chemicals with high efficiency (total decomposition of TCE, and up to 90% reduction of chloroform) using a relatively low accelerating voltage (<200 kV). The results have indicated that the removal of TCE and chloroform mainly depended on the absorbed dose of electron radiation     

640 Gb/s Timing Jitter-Tolerant Data Processing Using a Long-Period Fiber-Grating-Based Flat-Top Pulse Shaper

We report on the use of a novel all-fiber flat-top pulse shaping technique for improving performance and timing jitter tolerance of a switch made for 640-10 Gb/s signal demultiplexing. The jitter tolerance is increased to almost 30% of the one-bit time window, and an increase of the receiver sensitivity by 13 dB compared to a nonflat-top pulse is reported.     

基于电弧小波谱能量分析的输电线路单相自适应重合闸

提出一种基于小波谱能量分析的输电线路单相自适应重合闸方案。该方案在建立瞬时故障的一、二次电弧模型的基础上，利用DB6离散小波对故障相母线电压信号进行多尺度分析，并计算其高频分量在特定时间窗内的谱能量。瞬时故障时，谱能量较大，且在断路器跳开后的6个周期内均超过设定的门槛值，而永久故障时却不能满足上述条件。这一特征被用作故障识别的判据。仿真结果证实了本文所提方案的正确性。