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951.
Thomas Wiesner Dr. Zhu Wu Dr. Jie Han Prof. Dr. Lei Ji Dr. Alexandra Friedrich Dr. Ivo Krummenacher Michael Moos Prof. Dr. Christoph Lambert Prof. Dr. Holger Braunschweig Benjamin Rudin Dr. Hilmar Reiss Olena Tverskoy Dr. Frank Rominger Prof. Dr. Andreas Dreuw Prof. Dr. Todd B. Marder Dr. Jan Freudenberg Prof. Dr. Uwe H. F. Bunz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(69):e202201919
Tetraiodotetraazapentacene I4TAP , the last missing derivative in the series of halogenated silylated tetraazapentacenes, was synthesized via condensation chemistry from a TIPS-ethynylated diaminobenzothiadiazol in three steps. Single and double reduction furnished its air-stable monoanion and relatively air-stable dianion, both of which were characterized by crystallography. All three species are structurally and spectroscopically compared to non-halogenated TAP and Br4TAP . I4TAP is an n-channel material in thin-film transistors with average electron mobilities exceeding 1 cm2 (Vs)−1. 相似文献
952.
随着核酸自组装领域的飞速发展,除了作为遗传信息的载体外,核酸成为了一种具有高操作自由度和无限可能性的功能材料.基于核酸自组装原理的DNA纳米技术凭借其强大的可编辑性已经广泛应用于生物传感、纳米材料工程、医学诊疗以及分子计算机等领域.纳米孔作为一种新兴的单分子分析技术具有高分辨、高通量、免标记等特点,近年来在基因测序、分子物理化学性质分析等领域展示出了极大的应用潜力.作为一种新型高分辨表征技术,纳米孔已经在DNA纳米技术研究中崭露头角,被用于原位追踪和分析核酸分子的自组装行为.另一方面,DNA纳米技术也为纳米孔传感所面临的技术瓶颈提供了更多样化的解决思路,如借助功能核酸(Aptamer或DNAzyme)和无酶扩增核酸分子线路实现纳米孔对待测物的特异性增敏检测.本专论旨在通过对近期纳米孔技术与核酸自组装的跨领域研究成果进行系统性回顾,总结并展望纳米孔传感领域内核酸自组装的研究进展,以期为单分子生物分析、信息检索、基因分型和临床诊断等领域提供新思路和新方法. 相似文献
953.
954.
Wu Feng Liu Tong Liao Wanpeng Zhao Chunshen Dai Hongyu 《Russian Journal of General Chemistry》2022,92(1):125-131
Russian Journal of General Chemistry - N-[2-(4,4,5,5-Tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]ethanesulfonamide has been synthesized by the Miyaura borylation and sulfonylation reactions, and its... 相似文献
955.
Nie Renwang Wu Qingyong Yu Zhuqing Wang Aiguo Shen Xiaodong 《Journal of Thermal Analysis and Calorimetry》2022,147(12):6643-6654
Journal of Thermal Analysis and Calorimetry - Coral wastes are produced during the construction of island. The use of coral wastes in concrete is beneficial to economy and environment. Coral waste... 相似文献
956.
Dehydrogenation of an organic compound is the first and the most fundamental elementary reaction in many organic reactions. In ethanol oxidation reaction (EOR) to form CO2, there are a total of 46 pathways in C2HxO (x=1–6) species leading to the removal of all six hydrogen atoms in five C−H bonds and one O−H bond. To investigate the degree of dehydrogenation in EOR under operando conditions, we performed density function theory (DFT) calculations to study 28 dehydrogenation steps of C2HxO on Ir(100). An activation energy surface was then constructed and compared with that of the C−C bond cleavages to understand the importance of the degree of dehydrogenation in EOR. The results show that there are likely 28 dehydrogenations in EOR under fuel cell temperatures and the last two hydrogens in C2H2O are less likely cleaved. On the other hand, deep dehydrogenation including 45 dehydrogenations can occur under ethanol steam reforming conditions. 相似文献
957.
金属锂因具有极高的理论比容量(3860 mAh/g)和最低的电化学势(相对于标准氢电极为-3.04 V),被认为是下一代高比能锂离子电池的首选负极材料。然而,金属锂负极在电池循环过程中发生的刺状枝晶生长和体积变化等问题严重阻碍了其产业化应用进程。近年来研究表明,通过在金属锂中引入具有三维(3D)结构的宿主骨架,不但能有效抑制锂枝晶的生长,而且可以缓解金属锂负极的体积变化,从而提高金属锂电池的循环性能与安全性。因此,设计3D骨架/金属锂复合负极被认为是一种能有效解决金属锂问题的新兴策略。本文综述了热熔灌输法制备3D骨架/金属锂复合负极的研究进展。首先讨论了当前基于3D骨架的预存金属锂技术,然后着重分析了热熔灌输策略中3D骨架锂润湿性的影响因素,以及不同3D骨架修饰特征和改性方法。最后对3D骨架/金属锂复合负极和热熔灌输策略现存问题进行了总结并提出未来的发展方向。 相似文献
958.
Saiji Shen Chu Wu Yinghui Shang Hongdou Shen Yue Liao Yuting Guo Min Hu Xia Wang Gang Li Qigang Wang 《中国科学:化学(英文版)》2022,65(1):153-161
There are several natural materials which have evolved functional gradients,ingeniously attaining maximal efficacy from limited components.Herein,we utilized the spatiotemporal distribution of initiator acetylacetone to regulate the multienzyme polymerization and fabricate a chitosan-polymer hydrogel.The temporal priority order of acetylacetone was higher than phenolmodified chitosan by density functional theory calculation.The acetylacetone within the gelatin could gradually diffuse spatially into the chitosan hydrogel to fabricate the composite hydrogel with gradient network structure.The gradient hydrogel possessed a transferring topography from the two-dimensional pattern.A continuously decreased modulus along with acetylacetone diffusion was confirmed by atomic force microscope-based force mapping experiment.The water-retaining ability of various regions was confirmed by low-field nuclear magnetic resonance(NMR)and thermogravimetric analysis(TG)analysis,which led to the spontaneous actuation of gradient hydrogel with maximum 1821°/h curling speed and 227°curling angle.Consequently,the promising gradient hydrogels could be applied as intelligent actuators and flexible robots. 相似文献
959.
Karuppasamy Kohila Rani Rajkumar Devasenathipathy Jia-Zheng Wang Xiao-Yuan Hui Jian-De Lin Yi-Miao Zhang Liu-Bin Zhao Jian-Zhang Zhou De-Yin Wu Zhong-Qun Tian 《Current Opinion in Electrochemistry》2022
Plasmonic noble metal nanostructures have been targeted due to their strong surface plasmon resonance at photoelectrochemical interfaces. Recently, it has been concluded that, the plasmonic noble metal nanostructures on photoexcitation permit the transfer of effective hot carriers (hot electron/hole pair) to nearby adsorbed molecules where, the transformed hot carriers can efficiently decrease the activation barrier of a reaction. In this review, our recent achievements in the plasmon-mediated chemical reactions of organic molecules such as para-aminothiophenol, substituted para-aminothiophenol and para-nitrothiophenol at nanostructures modified noble metal electrodes using surface enhanced Raman spectroscopy, electrochemical methods, and theoretical calculations will be discussed. 相似文献
960.
Ke Yang Yi Zhou Yaping Wang Dr. Shaojing Zhao Xiaoli Wu Dr. Xiao Peng Li Huang Lirong Jiang Prof. Minhuan Lan Prof. Xiao-Yi Yi 《化学:亚洲杂志》2021,16(13):1780-1785
Image-guided photodynamic therapy (PDT) has received growing attention due to its non-invasiveness and precise controllability. However, the PDT efficiency of most photosensitizers are decreased in living system due to the aggregation-caused singlet oxygen (1O2) generation decreasing. Herein, we present an Iridium (III) pyridylpyrrole complex (Ir-1) featuring of aggregation-induced emission (AIE) and 1O2 generation characteristics for image-guided PDT of cancer. Ir-1 aqueous solution exhibits bright red phosphorescence peaked at 630 nm, large Stokes shift of 227 nm, and good 1O2 generation ability. The 1O2 generating rate of Ir-1 in EtOH/water mixture solution is 2.3 times higher than that of Rose Bengal. In vitro experimental results revealed that Ir-1 has better biocompatibility and higher phototoxicity compared with clinically used photosensitizers (Rose Bengal and Ce6), suggesting that Ir-1 can serve as a photosensitizer for image-guided PDT of cancer. 相似文献