Molecular design revitalizes the low-cost PTV-polymer for highly efficient organic solar cells

Developing photovoltaic materials with simple chemical structures and easy synthesis still remains a major challenge in the industrialization process of organic solar cells (OSCs). Herein, an ester substituted poly(thiophene vinylene) derivative, PTVT-T, was designed and synthesized in very few steps by adopting commercially available raw materials. The ester groups on the thiophene units enable PTVT-T to have a planar and stable conformation. Moreover, PTVT-T presents a wide absorption band and strong aggregation effect in solution, which are the key characteristics needed to realize high performance in non-fullerene-acceptor (NFA)-based OSCs. We then prepared OSCs by blending PTVT-T with three representative fullerene- and NF-based acceptors, PC₇₁BM, IT-4F and BTP-eC9. It was found that PTVT-T can work well with all the acceptors, showing great potential to match new emerging NFAs. Particularly, a remarkable power conversion efficiency of 16.20% is achieved in a PTVT-T:BTP-eC9-based device, which is the highest value among the counterparts based on PTV derivatives. This work demonstrates that PTVT-T shows great potential for the future commercialization of OSCs.     

绿色农业控制系统创新实践教学平台设计

以绿色农业应用为背景,融入现代科技设计创新实践教学平台.系统设计了清洁能源系统、能源储存系统、信息采集系统、智能温室控制系统、中央控制系统、人机交互以及云平台应用系统,实现能源自给自足、环境信息采集与存储、无线区域组网、系统信息显示与预警、智能控制等功能.系统内各功能部分,采用独立的模块化设计,易于组装移植,综合性、开...     

Injectable hybrid inorganic nanoscaffold as rapid stem cell assembly template for cartilage repair

Cartilage injuries are often devastating and most cannot be cured because of the intrinsically low regenerative capacity of cartilage tissues. Although stem-cell therapy has shown enormous potential for cartilage repair, the therapeutic outcome has been restricted by low survival rates and poor chondrocyte differentiation in vivo. Here, we report an injectable hybrid inorganic (IHI) nanoscaffold that facilitates fast assembly, enhances survival and regulates chondrogenic differentiation of stem cells. IHI nanoscaffolds that strongly bind to extracellular matrix (ECM) proteins assemble stem cells through synergistic 3D cell–cell and cell–matrix interactions, creating a favorable physical microenvironment for stem-cell survival and differentiation in vitro and in vivo. Additionally, chondrogenic factors can be loaded into nanoscaffolds with a high capacity, which allows deep, homogenous drug delivery into assembled 3D stem-cell-derived tissues for effective control over the soluble microenvironment of stem cells. The developed IHI nanoscaffolds that assemble with stem cells are injectable. They also scavenge reactive oxygen species and timely biodegrade for proper integration into injured cartilage tissues. Implantation of stem-cell-assembled IHI nanoscaffolds into injured cartilage results in accelerated tissue regeneration and functional recovery. By establishing our IHI nanoscaffold-templated 3D stem-cell assembly method, we provide a promising approach to better overcoming the inhibitory microenvironment associated with cartilage injuries and to advance current stem-cell-based tissue engineering.     

美国智库对中美科技竞争的观点解读及对策建议

[目的/意义]准确研判美国智库对于中美科技竞争的基本观点,是分析美国对中国进行科技竞争的舆论走向、战略认知与政策取向的重要依据。[方法/过程]选取美国8家主流智库的11份代表性研究成果作为研究样本,发现美国智库主要围绕中国科技实力的发展对美国产生的影响与美国如何同中国展开科技竞争这两个议题进行全面与深入的探讨。总体而言,美国主要智库已就中国科技实力对美国形成重要挑战这一点达成一定的共识,但在美国同中国展开科技竞争应实行的具体政策上存在一定的分歧。[结果/结论]美国智库总体上对中美科技竞争持消极观点,这是美国对中国的战略认知出现转变的结果。这些观点的传播将影响美国政府对华科技政策的取向,影响其他国家同中国展开的科技合作。中国应该在理性与辩证地看待美国主流智库观点的基础上,消除美国智库观点带来的消极影响,管控中美间在科技领域的战略竞争,努力拓展同美国以及其他国家在科技领域的合作空间,增强自主创新能力,化解中国在科技外交上可能面临的不利局面。     

提高法律文书课程教学实效的实践和思考

要深入研究法律文书课程的学科特点,探讨教学规律和教学方法,改变教学效果普遍不佳的现状。要重视启发式教学,调动学生的积极性,深化对于文书样式的理解。要引导学生分析比较,探求文书间的联系和文书制作的规律。在课时压缩的背景下,要精心选择、大胆取舍,突出教学重点。     

大连理工大学研究生论文写作与学术规范课程的探索与实践

从课程的背景与目的入手,对大连理工大学研究生公共基础课“论文写作与学术规范”的教学团队建设情况、教学内容与教材建设情况、实践效果与推广价值等进行了介绍和分析。     

法兰直线轴承视觉测量递阶式规划与行为分析

针对法兰直线轴承尺寸系列化与视觉测量过程行为多样化之间的复杂关联影响问题,提出由特征包容方案规划、基本动作规划和工位变换路线规划三阶段组成的递阶式测量行为规划策略,并设计了视觉测量规划与行为评估流程。以某型号方法兰直线轴承为对象,以评估不同测量行为、图像质量及图像处理算法之间的关联影响为任务,进行测量实验研究。实验结果表明,通过对测量行为进行递阶式规划与行为分析,便于获取测量行为变化造成测量结果波动的定量信息,得以反馈行为影响,从而引导行为优化,可促进视觉测量系统前、后处理功能的增强,有助于智能视觉测量的发展。     

混沌时间序列单变量和多变量重构的预测比较

提出了多变量混沌时间序列相空间延迟重构中延迟时间间隔和嵌入维数的选取方法，给出了多变量混沌时间序列的局部平均预测法，局部线性预测法和BP神经网络预测法等3种非线性预测方法．通过Lorenz系统的仿真计算表明，无论用3种非线性预测方法中的哪一种，多变量混沌时间序列要比单变量混沌时间序列的预测误差小得多，即使前的数据长度只有后的一半，前的预测误差也要小很多．另外从预测误差最小的角度验证了多变量混沌时间序列相空间延迟重构中延迟时间间隔和嵌入维数选取方法的有效性．     

多种结构形式的统一—如东县中学“科技楼”的主体结构设计试析

通过如东县中学“科技楼”的主体结构设计,探讨当代现代重点中学办学环节中硬件设施应具备的结构设计理念和设计方法,力图达到多种结构形式及技术与经济的完美统一。     

Static analysis of synchronism deployable antenna

INTRODUCTION Large antennas for space applications have some differences as compared to their counterparts de-signed and manufactured for ground usage. For a larger space antenna, the applied loads in space can be several orders of magnitude less than the gravity loading it is subjected to when being fabricated and assembled on the ground. Since the effect of gravity cannot be removed from any experimental verifica-tion performed on the ground, we must rely on the use of efficient and hig…