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991.
Changkun Zhang Yumin Qian Yu Ding Leyuan Zhang Xuelin Guo Yu Zhao Guihua Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(21):7119-7124
One promising candidate for high‐energy storage systems is the nonaqueous redox flow battery (NARFB). However, their application is limited by low solubility of redox‐active materials and poor performance at high current density. Reported here is a new strategy, a biredox eutectic, as the sole electrolyte for NARFB to achieve a significantly higher concentration of redox‐active materials and enhance the cell performance. Without other auxiliary solvents, the biredox eutectic electrolyte is formed directly by the molecular interactions between two different redox‐active molecules. Such a unique electrolyte possesses high concentration with low viscosity (3.5 m , for N‐butylphthalimide and 1,1‐dimethylferrocene system) and a relatively high working voltage of 1.8 V, enabling high capacity and energy density of NARFB. The resulting high‐performance NARFB demonstrates that the biredox eutectic based strategy is potentially promising for low‐cost and high‐energy storage systems. 相似文献
992.
Yu Wang Kiran M. Patil Shuanghong Yan Panke Zhang Weiming Guo Yuqin Wang Hong‐Yuan Chen Dennis Gillingham Shuo Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(25):8520-8524
O6‐carboxymethylguanine (O6‐CMG) is a highly mutagenic alkylation product of DNA, triggering transition mutations relevant to gastrointestinal cancer. However, precise localization of a single O6‐CMG with conventional sequencing platforms is challenging. Here nanopore sequencing (NPS), which directly senses single DNA bases according to their physiochemical properties, was employed to detect O6‐CMG. A unique O6‐CMG signal was observed during NPS and a single‐event call accuracy of >95 % was achieved. Moreover, O6‐CMG was found to be a replication obstacle for Phi29 DNA polymerase (Phi29 DNAP), suggesting this lesion could cause DNA sequencing biases in next generation sequencing (NGS) approaches. 相似文献
993.
Li‐Yuan Wu Yan‐Fei Mu Xiao‐Xuan Guo Wen Zhang Zhi‐Ming Zhang Min Zhang Tong‐Bu Lu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(28):9591-9595
Improving the stability of lead halide perovskite quantum dots (QDs) in a system containing water is the key for their practical application in artificial photosynthesis. Herein, we encapsulate low‐cost CH3NH3PbI3 (MAPbI3) perovskite QDs in the pores of earth‐abundant Fe‐porphyrin based metal organic framework (MOF) PCN‐221(Fex) by a sequential deposition route, to construct a series of composite photocatalysts of MAPbI3@PCN‐221(Fex) (x=0–1). Protected by the MOF the composite photocatalysts exhibit much improved stability in reaction systems containing water. The close contact of QDs to the Fe catalytic site in the MOF, allows the photogenerated electrons in the QDs to transfer rapidly the Fe catalytic sites to enhance the photocatalytic activity for CO2 reduction. Using water as an electron source, MAPbI3@PCN‐221(Fe0.2) exhibits a record‐high total yield of 1559 μmol g?1 for photocatalytic CO2 reduction to CO (34 %) and CH4 (66 %), 38 times higher than that of PCN‐221(Fe0.2) in the absence of perovskite QDs. 相似文献
994.
Lin-Lin Zhang Bing-Chao Da Shao-Hua Xiang Shuai Zhu Zi-Yun Yuan Zhen Guo Bin Tan 《Tetrahedron》2019,75(12):1689-1696
Quinones, precursors of aromatic structures, were firstly employed as the electrophiles for the organocatalytic Michael addition/cyclization cascade reaction with versatile 3-isothiocyanato oxindoles. Chiral bifunctional organocatalyst was appropriate for this enantioselective transformation to afford a variety of novel spirooxindoles, possessing a spirocyclic stereocenter adjacent to the aromatic ring, via asymmetric double arylation. These synthesized spirooxindoles are very difficult to access by the reported methods and were obtained in excellent chemical yields with excellent enantioselectivities. 相似文献
995.
FTIR-ATR has been used for understanding the interaction between bacteria and surfaces in the adsorption progress. 相似文献
996.
Yingying Wang Yang Zhou Min Lei Jinjun Hou Qinghao Jin Dean Guo Wanying Wu 《Tetrahedron》2019,75(9):1180-1185
A straightforward and general method has been developed for the synthesis of phthalimide derivatives from 2-iodobenzamides and PPh3/I2/HCOOH in the presence of a catalytic amount of Pd(OAc)2. The reaction results demonstrate that PPh3/I2/HCOOH is a facile, efficient and safe CO source. The whole process is carried out in toluene at 80?°C and furnishes the desired products in good to excellent yields. 相似文献
997.
Kun Wang Xia Guo Chennan Ye Yulong Wang Yuan Meng Xiaojie Li Prof. Maojie Zhang 《Chemphyschem》2019,20(20):2674-2682
To achieve high open-circuit voltage (Voc) and low acceptor content, the molecular design of a small-molecule donor with low energy loss (Eloss) is very important for solution-processable organic solar cells (OSCs). Herein, we designed and synthesized a new coplanar A−D−A structured organic small-molecule semiconductor with non-fused ring structure π-bridge, namely B2TPR , and applied it as donor material in OSCs. Owing to the strong electron-withdrawing effect of the end group and the coplanar π-bridge, B2TPR exhibits a low-lying highest occupied molecular orbital and strong crystallinity. Furthermore, benefiting from the coplanar molecular skeleton, the high hole mobility, balanced charge transport and reduced recombination were achieved, leading to a high fill factor (FF). The OSCs based on B2TPR : PC71BM blend film (w/w=1 : 0.35) demonstrates a moderate power conversion efficiency (PCE) of 7.10 % with a remarkable Voc of 0.98 V and FF of 64 %, corresponding to a low fullerene content of 25.9 % and a low Eloss of 0.70 eV. These results demonstrate the great potential of small-molecule with structure of B2TPR for future low-cost organic photovoltaic applications. 相似文献
998.
Shuaifei Guo Cuihong Sun Lingpeng Meng Yanli Zeng 《Journal of computational chemistry》2019,40(32):2827-2833
The mechanism of ring-opening polymerization of L-lactide by iodine trichloride (ICl3) catalyst has been explored by using density functional theory (DFT) calculations and three catalytic pathways were proposed. The first and second pathways belong to the halogen bond catalysis, and the third pathway involves the ICl3 catalysts participating in reactions. When the carbonyl group was maintained involved in the reaction and activated catalytically by the halogen bond, there are two possible pathways. The first pathway involves only one transition state, and the second pathway requires two transition states. There is another pathway in which ICl3 directly participates in the reaction, it is named the third pathway. Two different transition states of the four-membered rings are generated successively, the transfer of I─O bonds determined the progress of the reaction. Theoretical calculations in this work provide the most basic understanding of ring-opening polymerization of L-lactide by ICl3 catalysts. © 2019 Wiley Periodicals, Inc. 相似文献
999.
Alex Durkin Ivan Taptygin Dr. Qingyuan Kong Mohamad F. M. Gunam Resul Abdul Rehman Dr. Ana M. L. Fernández Prof. Adam P. Harvey Prof. Nilay Shah Dr. Miao Guo 《ChemistryOpen》2019,8(6):668-688
Poly(limonene carbonate) (PLC) has been highlighted as an attractive substitute to petroleum derived plastics, due to its utilisation of CO2 and bio-based limonene as feedstocks, offering an effective carbon capture and utilisation pathway. Our study investigates the techno-economic viability and environmental sustainability of a novel process to produce PLC from citrus waste derived limonene, coupled with an anaerobic digestion process to enable energy cogeneration and waste recovery maximisation. Computational process design was integrated with a life cycle assessment to identify the sustainability improvement opportunities. PLC production was found to be economically viable, assuming sufficient citrus waste is supplied to the process, and environmentally preferable to polystyrene (PS) in various impact categories including climate change. However, it exhibited greater environmental burdens than PS across other impact categories, although the environmental performance could be improved with a waste recovery system, at the cost of a process design shift towards energy generation. Finally, our study quantified the potential contribution of PLC to mitigating the escape of atmospheric CO2 concentration from the planetary boundary. We emphasise the importance of a holistic approach to process design and highlight the potential impacts of biopolymers, which is instrumental in solving environmental problems facing the plastic industry and building a sustainable circular economy. 相似文献
1000.