Design of periodic metal-insulator-metal waveguide back structures for the enhancement of light absorption in thin-film solar cells

To increase the absorption in a thin layer of absorbing material (amorphous silicon, a-Si), a light trapping design is presented. The designed structure incorporates periodic metal-insulator-metal waveguides to enhance the optical path length of light within the solar cells. The new design can result in broadband optical absorption enhancement not only for transverse magnetic (TM)-polarized light, but also for transverse electric (TE)-polarized light. No plasmonic modes can be excited in TE-polarization, but because of the coupling into the a-Si planar waveguide guiding modes and the diffraction of light by the bottom periodic structures into higher diffraction orders, the total absorption in the active region is also increased. The results from rigorous coupled wave analysis show that the overall optical absorption in the active layer can be greatly enhanced by up to 40%. The designed structures presented in this paper can be integrated with back contact technology to potentially produce high-efficiency thin-film solar cell devices.     

氢化物发生原子荧光光谱法测定三七中的砷

采用硝酸、高氯酸混合酸消解试样 ,氢化物发生原子荧光光谱法测定三七中的砷 ,并对仪器的工作条件、盐酸、还原剂用量、共存元素的干扰进行了试验。方法的检出限为 7.4 ng· g-1;测定精密度为 4 .67%— 7.0 1 % ;回收率在 97%— 1 0 1 %之间     

喹啉基粘度荧光探针的合成及其检测应用

作为细胞微环境的一个重要参数,粘度通过影响生物分子之间的相互作用实现对生物功能的调节.粘度的异常会导致多种疾病,如阿尔茨海默病、肺炎等.因此,实现粘度变化的精准检测对相关疾病的预防和诊断具有重要意义.本工作构建了新型喹啉基荧光探针QUI-VI.通过分子内的空间扭转(扭曲的光诱导分子内电荷转移机制),该探针实现了对粘度的检测.光学实验表明探针QUI-VI具有高化学和光稳定性能以及灵敏的粘度检测性能等优点.通过光谱实验、细胞成像以及组织成像实验,表明该探针具有显著的粘度敏感性,荧光强度会随着测试体系粘度的增强而增强.结合首次报道的小鼠肺炎组织粘度成像实验表明探针QUI-VI有望对肺炎的早期诊断提供一定的理论支撑.