Encapsulating metal organic framework into hollow mesoporous carbon sphere as efficient oxygen bifunctional electrocatalyst

Applying metal organic frameworks (MOFs) in electrochemical systems is a currently emerging field owing to the rich metal nodes and highly specific surface area of MOFs. However, the problems for MOFs that need to be solved urgently are poor electrical conductivity and low ion transport. Here we present a facile in situ growth method for the rational synthesis of MOFs@hollow mesoporous carbon spheres (HMCS) yolk–shell-structured hybrid material for the first time. The size of the encapsulated Zeolitic Imidazolate Framework-67 (ZIF-67) is well controlled to 100 nm due to the spatial confinement effect of HMCS, and the electrical conductivity of ZIF-67 is also increased significantly. The ZIF@HMCS-25% hybrid material obtained exhibits a highly efficient oxygen reduction reaction activity with 0.823 V (vs. reversible hydrogen electrode) half-wave potential and an even higher kinetic current density (J_K = 13.8 mA cm⁻²) than commercial Pt/C. ZIF@HMCS-25% also displays excellent oxygen evolution reaction performance and the overpotential of ZIF@HMCS-25% at 10 mA cm⁻² is 407 mV. In addition, ZIF@HMCS-25% is further employed as an air electrode for a rechargeable Zn–air battery, exhibiting a high power density (120.2 mW cm⁻² at 171.4 mA cm⁻²) and long-term charge/discharge stability (80 h at 5 mA cm⁻²). This MOFs@HMCS yolk–shell design provides a versatile method for the application of MOFs as electrocatalysts directly.     

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.     

叶下珠提取方法的研究概况

以国内发表的相关文献为依据,综述了叶下珠提取实验的溶剂选择、提取方法及化学成分的分离和测定方法等方面的研究成果,基于文献中有机溶剂的普遍使用,提出了实验过程应体现绿色化学理念的观点。     

Indonesia’s original sin: mass killings and capitalist expansion, 1965–66

Following an aborted coup attempt in October 1965, the Indonesian military organized what turned out to be one of the most horrifying massacres of the twentieth century. More than half a million people were killed while hundreds of thousands of others were detained for years in prison camps throughout the country. There are two major points that this paper attempts to make. First, that the killings are in fact a case of state violence despite of the efforts to make it look like spontaneous violence. Second, that the killings are crucial to the expansion of capitalism in Indonesia. Using Marx’s concept of ‘primitive accumulation’, it attempts to show that the mass killings and arrests, the expropriation of people from their houses and lands, and the elimination of working‐class political formations, are integral parts of an economic strategy of the New Order.     

《有机化学》精品课程的建设与实践

本文介绍了在《有机化学》精品课程建设中,如何从建设高素质的教师队伍、编写适合农业院校的教材、结合多媒体技术改革教学方法、建立适合素质教育的考核方法以及有机化学实验教学、独立开课、独立考核、建设精品课程网站、运用先进的网络技术和远程教育来弥补课堂教学的不足等方面,加强教学软硬件建设和改善,对传统有机化学教学进行改革的做法。     

社会学视野中1980年代主体性美学的理论谱系与逻辑框架

伴随着1980年代的思想解放运动,主体性哲学美学成为反思历史、重塑个体的强大文化思潮;文学与美学也在不断地与政治分化的过程中,实现了个体的自由和审美的理想,呈现出从集体话语、个体彰显,再到诗化哲学、审美自由和审美文化的历史转型。李泽厚的主体性实践哲学和刘再复的文学主体性,便成为"美学热"中从哲学到审美、从群体到自我、从机械反映论到主体实践论的理论动力,人道主义也不仅仅是思想解放的热情,更是以"主体性"的面貌成为系统化的理论表述和具有学科意识的理性思索。而此种回归人性、倡导自由和文化启蒙的美学思潮也将持续而深入地影响历史。     

植物酶对有机氧化反应的催化作用的研究

用植物酶对有机氧化反应的催化作用进行研究 ,找出它进行催化时的最适宜温度和最适宜的 PH范围。研究表明 :植物酶能加速有机化合物的氧化 ,植物酶作为催化剂的最适宜温度是5 0℃— 6 0℃ ,最适宜的 PH为 7— 8     

超声波在污水处理中的应用

本文介绍了超声波降解的原理、特点和影响因素以及目前取得的研究成果和主要结论，并对超声降解技术存在的问题和今后的发展趋势进行了讨论．     

浅谈有机化学教学中技校学生自学能力的培养

科学的发展和社会的进步要求每个人都具有一定的独立学习和不断获取新知识的能力,因此,学生自学能力的培养就至关重要。在有机化学教学中,通过课前预习、课堂教学、课后复习、化学实验各个环节,培养学生的自学能力。     

机械搅拌UASB反应器处理高浓度有机废水的研究

本文以实验为根据,论述了机械搅拌UASB反应器处理高浓度有机废水的成功启动过程。本实验在去除率达到50%后提高负荷,每次提高负荷的幅度为前次负荷的20～30%。实验历时60天,COD负荷达到10.88kg/(m3?d)时去除率达到70%,大大缩短了启动时间。