Engineering the Exciton Dissociation in Quantum‐Confined 2D CsPbBr3 Nanosheet Films

Recent years have witnessed a rapid development of all‐inorganic halide perovskite in optoelectronic devices. Ultrathin 2D CsPbBr₃ nanosheets (NSs) with large lateral dimensions have demonstrated exceptional photophysical properties because of their analogous exciton electronic structure to quantum wells. Despite the incredible progress on device performance, the photophysics and carrier transportation parameters of quantum‐confined CsPbBr₃ NSs are lacking, and the fundamental understanding of the exciton dissociation mechanism is far less developed. Here, a ligands rearrangement mechanism is proposed to explain why annealed NS films have an increased charge transfer rate and a decreased exciton binding energy and lifetime, prompting tunneling as a dominant way of exciton dissociation to separate photogenerated excitons between neighboring NSs. This facile but efficient method provides a new insight to manipulate perovskite nanocrystals coupling. Moreover, ultrathin 2D CsPbBr₃ NS film is demonstrated to have a enhanced absorption cross section and high carrier mobility of 77.9 cm² V^?1 s^?1, contributing to its high responsivity of 0.53 A W^?1. The photodetector has a long‐term stability up to three months, which are responsible for reliable perovskite‐based device performance.     

关于国际室内建筑师/设计师联盟2003年年会

2003年12月3～6日在印度孟买召开了国际室内建筑师/设计师联盟internationalfederationofin-teriorArchitects/interiorDesigners简称IFI第21届年会。中国建筑学会室内设计分会组织了由学会领导及各地设计师等17人组成的代表团参加这次国际大会,其中张世礼、劳智权、来增祥作为     

几种能源供暖方式的技术经济比较

分析了几种能源供暖方式的初投资和经营费用，给出了费用年值的计算公式。采用费用年值法对几种能源供暖方式的经济性和使用过程的技术性进行了比较。     

可注浆式钢边橡胶止水带的试制及应用

介绍了可注浆式钢边橡胶止水带的试制及应用情况。经注浆试验和工程应用证明,可注浆式钢边橡胶止水带只要注浆管安装正确,浆液容易进入混凝土裂缝中,起到明显的止水效果。     

消焰剂对煤矿导爆索安全性的影响

普通导爆索用于矿井中,在传爆中易引燃瓦斯、煤尘,造成爆炸事故.文章在普通导爆索的药芯和外层添加消焰剂,同时采用探针测量爆速,利用充甲烷气体装置测试安全性.结果表明药芯中掺加氯化石蜡,外包覆氯化钠的导爆索爆速降低,而安全性显著提高.     

Application of microcapsule technology in wool dyeing北大核心

The paper introduces a kind of wool dyeing process, namely the microcapsule dyeing process. It simply introduces some basic concepts of wool and microcapsule, and introduces the use of microcapsule dyes on wool in detail, which includes the selection of wall materials and the preparation methods of wool microcapsule dyes, the encapsulation efficiency and stability of microcapsule dyes, the interactions and combinative efficiency of wool with microcapsules, and the dyeing performance of microcapsule dyes. It summarizes the research application situations of microcapsule dyes on wool dyeing in recent years, and discusses the feasibility of microcapsules dyeing technology used in wool dyeing. It expounds the importance and application prospects of microcapsule technology in wool dyeing and finishing.     

Enhancing the electrical and optoelectronic performance of nanobelt devices by molecular surface functionalization

By functionalizing the surfaces of ZnO nanobelts (NBs) with a thin self-assembled molecular layer, the electrical and optoelectronic performances of a single NB-based device are drastically improved. For a single NB-based device, due to energy band tuning and surface modification, the conductance was enhanced by 6 orders of magnitude upon functionalization; a coating molecule layer has changed a Schottky contact into an Ohmic contact without sophisticated deposition of multilayered metals. A functionalized NB showed negative differential resistance and exhibited huge improved photoconductivity and gas sensing response. The functionalized molecular layer also greatly reduced the etching rate of the ZnO NBs by buffer solution, largely extending their life time for biomedical applications. Our study demonstrates a new approach for improving the physical properties of oxide NBs and nanowires for device applications.     

固定床吸附分离C_8芳烃的数学模型

以自制和进口Y型合成沸石在室温下液相吸附分离对二甲苯-乙苯二元体系,研究固定床吸附分离C_8芳烃的数学模型.数模中的传质速率方程用总传质系数表征其传质特点,结合相平衡和物料衡算方程,进行数值积分,得到的理论透过曲线与实验曲线相近.为了进一步探索吸附过程动力学和传质机理,对液相控制、固相控制和固液相联合控制三种数学模型进行了初步探索和比较,发现固相控制模型更适合本研究体系.