Regulation of Polymer Configurations Enables Green Solvent-Processed Large-Area Binary All-Polymer Solar Cells With Breakthrough Performance and High Efficiency Stretchability Factor

With the great potential of the all-polymer solar cells for large-area wearable devices, both large-area device efficiency and mechanical flexibility are very critical but attract limited attention. In this work, from the perspective of the polymer configurations, two types of terpolymer acceptors PYTX-A and PYTX-B (X = Cl or H) are developed. The configuration difference caused by the replacement of non-conjugated units results in distinct photovoltaic performance and mechanical flexibility. Benefiting from a good match between the intrinsically slow film-forming of the active materials and the technically slow film-forming of the blade-coating process, the toluene-processed large-area (1.21 cm²) binary device achieves a record efficiency of 14.70%. More importantly, a new parameter of efficiency stretchability factor (ESF) is proposed for the first time to comprehensively evaluate the overall device performance. PM6:PYTCl-A and PM6:PYTCl-B yield significantly higher ESF than PM6:PY-IT. Further blending with non-conjugated polymer donor PM6-A, the best ESF of 3.12% is achieved for PM6-A:PYTCl-A, which is among the highest comprehensive performances.     

项目导向的计算机审计教学方法的创新与探索

针对目前计算机审计课程教学过程中存在课堂教学与计算机审计实践脱节问题,笔者根据自身教学经验,并结合参与国家审计署项目审计的经历,提出以项目为导向、整体模块化、模块多样化的计算机审计教学方法,实现教学理论与审计实践的较好结合,充分调动教学中两个主体的主观能动性,提高了教学质量。     

Numerical solutions of Duffing equations involving both integral and non-integral forcing terms

In this paper, an improved variational iteration method is presented for solving Duffing equations involving both integral and non-integral forcing terms. The main advantage of this modification over the standard variational iteration method (VIM) is that it can avoid unnecessary repeated computation in determining the unknown parameters in the initial solution. Numerical results reveal that the improved method is simple and efficient.     

一类混沌序列线性复杂度的分析

针对传统密码学中由线性移位寄存器生成的序列在统计特性上的不足,提出一种基于混沌的序列密码生成方法,并在有限精度实现时引入Legendre扰动序列使得输出具有良好的统计特性。用B-M算法对其进行线性复杂度分析,并与等效的线性反馈移位寄存器的复杂度进行比较,结果显示该混沌序列具有良好的非线性特性,保密性好且软件实现简单。     

Wafer-level multilayer integration of RF passives with thick BCB/metal interlayer connection in silicon-based SiP

This paper presents an integration technology for RF passives using benzocyclobutene (BCB)/metal multilayer interconnection for system-in-package applications. This technology has been specially developed for RF subsystem packages in which a thick polymer, BCB (more than 15 μm thick), is adopted as dielectric with lossy silicon as substrate for its excellent characteristics. Both dry-etch BCB and photosensitive BCB are applied in this work, and their processes are briefly introduced and compared. An RF power divider, an MIM capacitor, different types of RF inductors as well as a coupled microstrip based band-pass filter are fabricated and measured at wafer level. The results show good electrical performances, and accordingly the passives are well applicable in RF band. Moreover, the subsystem models including monolithic chips connected with passives are presented.     

图书馆读者网络问卷调查系统的设计与实现

本文为主要介绍,基于B／S结构,设计和开发网络版的读者问卷调查系统,此系统对调查问卷结果的分析和统计做出详细的描述,通过和图书馆其它系统的联合使用,形成特有的读者问卷调查反馈服务平台,本文参与“‘网络环境下高校用户信息行为实证研究”课题立项的研究。     

Machinability of Metal Matrix Composites Reinforced by 3-D Network Structure

Metal matrix composites reinforced by three-dimensional (3-D) continuous network structure reinforcement (3DCNRMMC) are difficult to machine due to serious tool wear and poor surface roughness caused by the brittle and hard reinforcement which interpenetrate into ductile matrix. In order to achieve the approach of low cost of 3DCNRMMC, the machinability of it needs to be understood. The influences of three cutting parameters and volume fraction of reinforcement on cutting force were analyzed in detail. The results indicate that: (1) Due to the brittle phase(s) introduced into ductile matrix of composites, there is a large fluctuation of cutting force causing deterioration of machinability. The fluctuation ranges of cutting forces, initially increase rapidly with the increase of volume fraction of reinforcement and then decrease finally, are largest at the range of the volume fraction of 55–65%; (2) The influence of cutting parameters on cutting force is obvious. With the increases of cutting speed, cutting force decreases gradually unless cutting speed exceeds the value of 209 m/min. Cutting forces increase with increasing feed rate and depth of cut; (3) Owing to the large fluctuation of cutting force, there were some cratered surfaces caused by Si₃N₄ reinforcement pulling-out and flaking-off. Some brittle phase protruding from the machined surface caused the deterioration of machined surface.     

DWDM上25.344 Mbit/s光监控信息传送系统的设计

采用25.344 Mbit/s光监控信息传送技术可以更好地满足当前密集波分复用(DWDM)系统中不断增加的网络监控信息和附加业务的需要.文章首先介绍了25.344 Mbit/s光监控信息传送系统的技术方案,然后详细描述了其帧结构、码型设计以及硬件实现的框图,最后介绍了该技术的优点.