磁场对P3HT:PCBM活性层的薄膜形貌及光电性能的影响北大核心CSCD

以P3HT(Poly(3-Hexylthiophene))为电子给体,PCBM([6,6]-Phenyl C61Butyric Acid Methyl Ester)为电子受体,在活性层P3HT:PCBM的退火过程中,利用磁场对活性层有机分子的排列取向作用,制备了有机体异质结太阳能电池。研究结果表明:当磁场强度为0.9MA/m时,器件的短路电流密度从7.414A/cm2提高到8.332A/cm2,填充因子也相应地增加,但开路电压却有所降低,最高的光电转换效率为2.562%。由光致发光光谱和原子力显微图像可知,磁场对活性层的结晶度、内部分子排列和表面形貌都有明显的影响。     

Power Density Distribution Simulation and Relevant Heat Effect Calculation of a High-power CO_2 Laser with Low Order Modes

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　Ｉｎｔｈｅｉｎｄｕｓｔｒｉａｌａｐｐｌｉｃａｔｉｏｎｒｅｓｅａｒｃｈｏｆｌａｓｅｒｂｅａｍｈｅａｔｐｒｏｃｅｓｓｉｎｇａｎｄｔｒｅａｔｍｅｎｔ,ｄｕｅｔｏｔｈｅｓｈｏｒｔｉｎｔｅｒａｃｔｉｏｎｔｉｍｅｏｆｌａｓｅｒｗｉｔｈｔｈｅｍａｔｅｒｉａｌ,ｔｈｅｈｅａｔ ａｆｆｅｃｔｅｄａｒｅａｉｓｌｉｍｉｔｅｄｉｎｔｈｅａｒｅａｎｅａｒｔｈｅ ｐｏｓｉｔｉｏｎｉｒｒａｄｉａｔｅｄｂｙｔｈｅｌａｓｅｒｂｅａｍ .Ｓｕｐｐｏｓｅｄｔｈａｔｔｈｅｗｏｒｋｐｉｅｃｅｉｓａｓｅｍｉ ｉｎｆ…     

Study on improvement of the laser uniformity transformation of overlapping-image waveguide cavity

After propagating through the overlapping-image integral mirror, the interference fringe is a major factor that affects the uniformity of the image plane. In this paper, a He-Ne laser is used as light source, and the complex amplitude of the incident laser beam is modulated by an alternating electric field controlled vibrating mirror that is placed before the optical system. The experimental results show that after propagating through the overlapping-image integral mirror, not only the contrast of the interference fringes on the image plane is depressed, but also the uniformity of the intensity distribution of the transformed light beam is improved. Finally, based on the experimental results, two optical systems that can be applied to high power laser uniformity transformation are presented.     

数字散斑相关方法用于PMMA弹性模量的测量

通过三点弯载荷实验，利用数字散斑相关方法得到了试件载荷过 程中对应的载荷-位移曲线. 依据实验中试件载荷前后位移的变化量，对常用 工程材料PMMA的弹性模量进行了测定. 实验数据表明所测弹性模量较为真实、客观， 相对误差较小. 该研究方法为同类材料未知弹性模量的测定提供了一种行之有效的 测量途径.     

Power Density Distribution Simulation and Relevant Heat Effect Calculation of a High-power CO2 Laser with Low Order Modes

The vertical excitation axial-flux kilowatt CO2 laser is an equipment widely used in the high-power laser heat treatment industrial applications. The experimental measurements indicate that the power density distribution of laser beam is generally of ring distribution with a sunken at the center, therefore the laser beam cannot be simply regarded as base mode Gaussian beam. In this paper, such laser beam is regarded as the non-interference superposition of TEM00 and TEM01 mode beams, the method to determine the simulation parameters is discussed, and the relevant heat effect calculation equation is deduced.     

The application of arbitrary incidence laser beams heat treatment temperature field calculation formulas

Based on the calculation formulas of heat treatment temperature field for an arbitrary incident laser intensity distribution, the transformation intensity distribution of CO2 laser beam passing an integrating mirror is studied theoretically and experimentally. The derived formulas are applied in laser heat treatment research which is transformed by optical system, and the theoretical calculation results are compared with experimental results. It is shown that the formulas can be used to calculate the laser heat treatment temperature field accurately, and the calculation speed is obviously faster than the numerical calculation methods with the same precision. The calculation software can be used to select proper experiment parameters.     

基于应变响应的预损伤钢筋混凝土梁损伤识别研究

针对大型桥梁工程结构健康检测中难以实施人工激励的实际状况,提出和推导了环境激励下由应变响应实现结构损伤识别的快速方法及原理。以应变计获取不同损伤状况下钢筋混凝土梁的应变响应信息,研究了预损伤钢筋混凝土梁结构频率、振型、模态阻尼等动力特性在不同损伤状况下的演变规律。研究结果表明,本文所提原理和方法可直接、快速实现环境激励下钢筋混凝土桥梁结构的损伤识别。     

柔性碳纸上组装ZnO纳米阵列及其可见光下光电探测

采用两步水热法在柔性碳纤维纸上成功原位生长ZnO纳米阵列.该纳米阵列具有单晶结构,优良的电导传输效率等特点.柔性碳纤维纸作为一种环保材料,有着极好导电性、能快速传输光生载流子.对所制样品进行可见光下光电探测,实验结果显示:碳纤维上制备ZnO纳米阵列在可见光下有较高光电流.通过表征与分析,提出零价氧空位在ZnO提供能级致使其在可见光下能够激发.