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1.
Herein, we successfully construct the 3D biocompatible graphene through crosslinking 2D graphene nanosheet onto carbon fiber paper with poly(diallyldimethylammonium chloride) (PDDA) as anode of the alcohol biofuel cell. Compared with the bioanode without 3D graphene, the current density and output power of PDDA-graphene-ADH bioanode is increased by 23 % and 41 % at a high concentration of ethanol at pH 8.9, suggesting the stabilization role of graphene in enzyme loading. The study provides us a deep analysis on structures and performances of the bioanode incl. electrochemistry, X-ray photoelectron spectra, and atomic force microscopy images, which is significant to develop the new methods to construct 3D porous electrodes in energy conversion device. 相似文献
2.
分子张力作为空间设计的重要组成部分正成为调控有机半导体的重要手段。由于分子内产生的拉伸张力、扭曲/弯曲张力以及空间张力而导致p轨道排布重组和构型构象结构发生变化,最近各种几何与拓扑结构的高张力有机半导体材料相继被报道,这使得高张力有机半导体材料成为有机电子领域研究的焦点。为了进一步梳理分子张力在有机半导体材料中扮演的角色与价值,该综述从分子张力的类型、实验与理论量化以及可视化出发,总结了高张力共轭芳烃的分子设计策略、与其光电性能分子张力之间的关系,以及这类新兴材料在光电领域的应用。最后,对高张力共轭芳烃的研究前景进行了展望,阐述了该类材料所面临的机遇与挑战。 相似文献
3.
针对架空输电线路铁塔中常用的四地脚螺栓塔脚板进行了抗拉承载力试验和理论计算方法研究。首先,选取8个试件进行塔脚板抗拉承载力试验研究,分析塔脚底板板厚及有无加劲板对塔脚板抗拉承载力的影响;其次,通过有限元模拟塔脚板的应力分布情况,并结合“塑性分析,弹性设计”的思想,提出了一种基于屈服线理论的四地脚螺栓塔脚板抗拉承载力计算公式;最后,与试验结果、有限元仿真结果、已有技术规定中的计算结果进行了对比。结果表明:建议公式与试验结果和仿真结果较为吻合,相关技术规定中的计算结果偏于保守,验证了本文建议公式的精确性;底板厚度和加劲板的作用对塔脚板承载力影响较大。研究结果可为输电铁塔四地脚螺栓塔脚板结构设计提供参考。 相似文献
4.
Kamila B. Muchowska Dominic J. Pascoe Stefan Borsley Ivan V. Smolyar Ioulia K. Mati Catherine Adam Gary S. Nichol Kenneth B. Ling Scott L. Cockroft 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(34):14710-14716
Interactions between carbonyl groups are prevalent in protein structures. Earlier investigations identified dominant electrostatic dipolar interactions, while others implicated lone pair n→π* orbital delocalisation. Here these observations are reconciled. A combined experimental and computational approach confirmed the dominance of electrostatic interactions in a new series of synthetic molecular balances, while also highlighting the distance-dependent observation of inductive polarisation manifested by n→π* orbital delocalisation. Computational fiSAPT energy decomposition and natural bonding orbital analyses correlated with experimental data to reveal the contexts in which short-range inductive polarisation augment electrostatic dipolar interactions. Thus, we provide a framework for reconciling the context dependency of the dominance of electrostatic interactions and the occurrence of n→π* orbital delocalisation in C=O⋅⋅⋅C=O interactions. 相似文献
5.
Xu Yongjian Yu Ling Liang Lizhen Hu Chundong Xie Yahong Xie Yuanlai Jiang Caichao Liu Sheng Wei Jianglong Liu Zhimin Sheng Peng Tao Ling 《Journal of Thermal Analysis and Calorimetry》2020,139(1):527-533
Journal of Thermal Analysis and Calorimetry - According to EAST’s experimental plan, the long-pulse and high-power operation of neutral beam injector is the requirement for EAST. In this... 相似文献
6.
PENG Xiaoyu ZHAO Anran HUANG Kelin HU Tingju LIU Buming HUANG Yan CHEN Hailan CHAI Ling LIN Cuiwu 《高等学校化学研究》2020,36(5):795-803
Structural modification of native compounds is an effective way to develop new drugs with increased pharmacological activities and improved material characteristics. In this study, caffeic acid sulphonamide derivatives(CSs) were synthesised by conjugating sulphonamides to the backbone of caffeic acid. The structures of these derivatives were elucidated by means of Fourier transform infrared spectroscopy(FTIR), 1H NMR, 13C NMR, and electrospray ionization mass spectroscopy(ESI-MS). A content determination method was established by ultraviolet detection. The lipophilicity, 2,2-diphenyl-1-picrylhydrazy free radical(DPPH) scavenging capacity, anti-coagulant effects, anti-bacterial activity, cytotoxicity, in vitro anti-proliferative activity against tumour cells, and the ability of the compounds to promote the proliferation of chondrocytes were evaluated. The results indicate that CSs exhibit strong DPPH scavenging activity, high lipophilicity, good anti-coagulant activities, wide anti-bacterial activity range, low cytotoxicity, and an excellent ability to promote chondrocyte proliferation. 相似文献
7.
In the conventional scheme of generating strong mechanical squeezing by the joint effect between mechanical parametric amplification and sideband cooling, the resolved sideband condition is required so as to overcome the quantum backaction heating. In the unresolved sideband regime, to suppress the quantum backaction, a χ(2) nonlinear medium is introduced to the cavity. The result shows that the quantum backaction heating effect caused by unwanted counter-rotating term can be completely removed. Hence, the strong mechanical squeezing can be obtained even for the system far from the resolved-sideband regime. 相似文献
8.
The etch-stop structure including the in-situ SiN and AlGaN/GaN barrier is proposed for high frequency applications.The etch-stop process is realized by placing an in-situ SiN layer on the top of the thin AlGaN barrier.F-based etching can be self-terminated after removing SiN,leaving the AlGaN barrier in the gate region.With this in-situ SiN and thin barrier etch-stop structure,the short channel effect can be suppressed,meanwhile achieving highly precisely controlled and low damage etching process.The device shows a maximum drain current of 1022 mA/mm,a peak transconductance of 459 mS/mm,and a maximum oscillation frequency(fmax)of 248 GHz. 相似文献
9.
Polyaniline (PANI)/MIL-88A(Fe) (Px@M88) composites were constructed through a simple one-pot hydrothermal method. The photocatalytic and photo-Fenton activities of Px@M88 composites toward reduction of Cr(VI) and degradation organic pollutants were explored by white light irradiation. PANI, as a conductive polymer, can improve MIL-88A(Fe)’s conductivity and the efficiency of photogenerated e−–h+ pair separation. In the presence of H2O2, a photo-Fenton reaction occured to boost the degradation efficiency of organic pollutants like bisphenol A. In addition, P9@M88 showed excellent recycling and stability in cycling experiments. Finally, a possible reaction mechanism for photocatalytic degradation was proposed and verified by X-ray photoelectron spectroscopy and electron spin resonance determination and electrochemical characterizations. 相似文献
10.
针对铌酸锂(LN)电光调Q开关性能一致性差、退压式调Q时无法完全关断光路的问题进行了系统研究.在闪光灯泵浦Nd:YAG激光系统中,对多块LN电光调Q开关的退压式电光调Q性能进行了对比测试,并从电光调Q理论出发,分析了光路无法关断的可能原因.在此基础上,利用X射线定向仪、锥光干涉法对各晶体的轴向偏差、光学均匀性进行了表征,首次发现了LN晶体的电光不均匀性,即感应主轴偏离理论上的45°方向、通光截面各处感应双折射不一致.通过对比实验,证实了电光不均匀性是造成光路无法关断、不同开关性能差异较大的主要原因. 相似文献