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Redox flow batteries (RFBs) usually contain aqueous or organic electrolytes. The aim of this communication is to explore the suitability of room temperature ionic liquids (RTILs) as solvents for RFBs containing metal complexes. Towards this aim, the electrochemistry of the metal acetylacetonate (acac) complexes Mn(acac)3, Cr(acac)3, and V(acac)3 was studied in imidazolium-based RTILs. The V2+/V3+, V3+/V4+, and V4+/V5+ redox couples are quasi-reversible in 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, [C2C1Im][N(Tf2)]. The Mn(acac)3 and Cr(acac)3 voltammetry, on the other hand, is irreversible in [C2C1Im][N(Tf2)] at glassy carbon (GC) but the rate of the Mn2+/Mn3+ reaction increases if Au electrodes are used. Charge–discharge measurements show that a coulombic efficiency of 72% is achievable using a V(acac)3/[C2C1Im][N(Tf2)]/GC cell. 相似文献
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Dr. Ruisheng Zhao Prof. Dr. Xiang Zhao Prof. Dr. Xingfa Gao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):960-964
Nanocarbon oxides have been proved to possess great peroxidase‐like activity, catalyzing the oxidation of many peroxidase substrates, such as 3,3′,5,5′‐tetramethylbenzidine (TMB) and o‐phenylenediamine dihydrochloride (OPD), accompanied by a significant color change. This chromogenic reaction is widely used to detect glucose and occult blood. The chromogenic reaction was intensively investigated with density functional theory and molecular‐level insights into the nature of peroxidase‐like activity were gained. A radical mechanism was unraveled and the carboxyl groups of nanocarbon oxides were identified as the reactive sites. Aromatic domains connected with the carboxyl groups were critical to the peroxidase‐like activity. 相似文献
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Liu Yu-Xuan Wang Liang Zhou Ke Wu Hong-Bo Zhou Xiao-Bo Ma Zai-Fei Guo Sheng-Wei Ma Wei 《高分子科学》2022,40(8):951-959
Chinese Journal of Polymer Science - The aligned molecular packing structure is vital to the anisotropic charge transport in conjugated polymer and small molecule thin films. However, how this... 相似文献
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发声过程中声带组织振动的黏膜波测量对于声带组织力学特性和病理机制研究具有重要意义。本研究利用多普勒激光测振(Laser Doppler Vibrometer,LDV)和电声门图时间同步方法,对声带上表面的振动过程进行了重建,并基于该结果估计了黏膜波传播速度。通过离体犬喉发声实验,激光测振方法能够得到与高速光学方法相一致的黏膜波速度估计,并且能够重建不同时刻的声带上表面形态,证明了该方法应用于声带上表面振动特性研究的可行性和有效性。然而,由于单点测振的局限和时间同步的要求,稳态发声是保证该方法测量准确性的重要条件。 相似文献
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The importance of thermophoresis and its essential role in particle migration have led to many published reports (i.e. aim and objectives). However, there exists no report on thermo-migration of tiny/nano-sized particles in the motion of various fluids. A meta-analysis on the significance of either nano or tiny particles exposed to thermophoretic force owing to temperature gradient during the dynamics of liquid substances is deliberated upon in this report. The method of slope linear regression through the data point was adopted to scrutinize sixty (60) published reports in which the effects of thermophoresis (thermodiffusion) is deliberated upon. The outcome of the study shows that different responses to the force of a temperature gradient are sufficient enough to enhance the temperature distribution and the concentration of non-Newtonian fluid due to an increase in thermophoresis. Thermophoretic effect increases the concentration of fluids in which the relationship between the shear stress and shear strain is non-linear. Skin friction coefficients is a decreasing function of thermophoresis. Increase in thermophoretic deposition is achievable due to an increase in thermophoresis. The effect of haphazard motion of nanoparticles should be investigated when it increases negligibly and considerably large. Thermal radiation strongly influences the significance of thermo-migration of tiny particles on fluid flow. 相似文献
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针对设计的一种场畸变气体开关,研究中间电极材料分别为不锈钢和黄铜条件下的烧蚀特性,结合开关寿命期间静态与触发特性的变化规律,获得决定开关寿命的关键因素,为三电极场畸变气体开关的性能优化提供理论支撑。研究结果表明,采用不锈钢和黄铜作为中间电极的烧蚀区域以及表面粗糙度均随着放电次数增加而增大,黄铜电极烧蚀较为严重且表面有明显的烧蚀圆斑,不锈钢电极则具有更高的表面粗糙度,阴阳极表面烧蚀存在明显差异,随着放电次数的增加,击穿点向电极边缘区域集中,影响开关的沿面绝缘特性,是导致开关寿命终结的主要原因。 相似文献