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71.
Deoxyribonucleic acid (DNA) was electrochemically deposited on a carbon ionic liquid electrode to give a biosensor with excellent redox activity towards paraquat as shown by cyclic voltammetry and differential pulse voltammetry. Experimental conditions were optimized with respect to sensing paraquat by varying the electrochemical parameters, solution pH, and accumulation time of DNA. Under the optimized conditions, a linear relation exists between the reduction peak current and the concentration of paraquat in the range from 5?×?10?8 mol L?1 to 7?×?10?5 mol L?1, with a detection limit of 3.6?×?10?9 mol L?1. The utility of the method is illustrated by successful analysis of paraquat in spiked real water samples. Figure
The DNA was electrodeposited onto the CILE under +1.5?V for 1200?s. The electrochemical behaviors of paraquat on the modified electrode had been studied by cyclic voltammetry and differential pulse voltammetry. Five ml phosphate buffer (pH 7.0) solution was added into an electrochemical cell (10?ml) and then paraquat was successfully added into the cell. The differential pulse voltammograms were recorded when swept from ?0.8?V to ?0.3?V. The peak currents at about ?0.63?V for paraquat were measured. 相似文献
72.
Transport across gap junction channels (GJCs) between neighboring cells is critical to synchronizing cell's electrical and metabolic activities and maintaining cell homeostasis. Here we present a non-invasive microfluidic method to measure molecular diffusion across GJCs in multiple 1D cell arrays in real time. Using the chip, selective loading of a membrane permeant fluorescence dye (carboxyfluorescein) in Normal Rat Kidney (NRK) cells shows that the dye was able to diffuse through three cells along single cell chains in ~35 minutes. Application of 100 μM 2-aminoethoxydiphenyl borate (2-APB) reversibly inhibits connexin-43 gap junctions in NRK cells; 0.8 mM 1-heptanol inhibits the diffusion partially. The method offers rapid exchange of reagents, enabling sequential screening of multiple gap junction specific drugs with only one preparation of cells. It is capable of measuring gap junction mediated diffusion between single cells. 相似文献
73.
We devised a new ratiometric fluorescent probe for the detection of chloride ions. This synthesized probe was applied to the ventricular myocytes to successfully realize dynamic imaging of Cl(-) concentration fluctuations during the myocardial ischemia course. 相似文献
74.
76.
Nannan Meng Cuibo Liu Yang Liu Yifu Yu Bin Zhang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(52):19084-19088
Efficient electrochemical reduction of CO2 and H2O into industrial syngas with tunable CO/H2 ratios, especially integrated with anodic organic synthesis to replace the low‐value oxygen evolution reaction (OER), is highly desirable. Here, integration of controllable partial substitution of zinc (Zn) with amine incorporation into CdS‐amine inorganic‐organic hybrids is used to generate highly efficient electrocatalysts for synthesizing syngas with tunable CO/H2 ratios (0–19.7), which are important feedstocks for the Fischer–Tropsch process. Diethylenetriamine could enhance the adsorption and accelerate the activation of CO2 to form the key intermediate COOH* for CO formation. Zn substitution promoted the hydrogen evolution reaction (HER), leading to tunable CO/H2 ratios. Importantly, syngas and dihydroisoquinoline can be simultaneously synthesized by pairing with anodic semi‐oxidation of tetrahydroisoquinoline in a ZnxCd1?xS‐Amine ∥ Ni2P two‐electrode electrolyzer. 相似文献
77.
Aiming to identify the spiro metallaaromatic systems with potential application value, (C10H10M)2?(M=Ni, Pd, Pt) derivatives were theoretically investigated. (C10H10M)2?-Iso1, which has two 6-membered rings(6MRs) connected by the M spiro atom, is a 14π-aromatic as a whole plane. (C10H10M)2?-Iso2 has one 6π-aromatic 5MR and one 10π-aromatic 7MR connected by the spiro atom. The free (C10H10M)2? dianions could not exist due to their rather high frontier orbital energies, while the neutral (C10H10M)Li2 compounds are extremely stable against dissociation. Since (C10H10M)Li2 coumponds are not fully coordinated, they trend to form (C10H10M)Li42+ dications, or even[(C10H10M)Li2]n polymers. Arguably, (C10H10M)2? planes are not the only examples for spiro metallaaromaticity, their derivatives are also potential material building blocks. 相似文献
78.
Nannan Zhao Zhongkui Sun Wei Xu 《The European Physical Journal B - Condensed Matter and Complex Systems》2018,91(1):20
The amplitude death (AD) phenomenon is found in the relay system in the presence of the mixed couplings composed of attractive coupling and repulsive coupling. The generation mechanism of AD is revealed and shows that the middle oscillator achieving AD is a prerequisite to further suppress oscillation of the outermost oscillators for the paradigmatic Stuart-Landau and Rössler models. Moreover, regarding the Stuart-Landau relay system as a small motif of star network, we also observe that the mixed couplings can facilitate AD state of the whole network system. Particularly, the threshold of coupling strength is invariable with the change of network size. Our findings may shed a new insight to explore the effects of hybrid coupling on complex systems, also provide a new strategy to control dynamic behaviors in engineering science and neuroscience fields. 相似文献
79.
用Ziegler-Natta(Z-N)催化剂MgCl2/TiCl4/BMF-AlEt3(BMF代表内给电子体9,9-二甲氧基甲基芴),采用分段聚合的方法制备了PP/EPR原位共混物,通过改变乙丙共聚的时间调节聚合物中乙烯的含量.使用核磁共振(13C-NMR)、凝胶渗透色谱(GPC)、示差扫描量热分析法(DSC)、动态力学分析(DMA)、扫描电子显微镜(SEM)和偏光显微镜(PLM)等研究了聚合物的结构和形态特征.研究发现,分段聚合制备的PP/EPR共混物是一种包括丙烯均聚物、乙丙无规和嵌段共聚物在内的多组分混合物.动态力学的结果显示混合物中聚丙烯与乙丙无规共聚物的玻璃化转变峰出现了内移现象,说明两者呈现部分相容性.扫描电镜的照片表明了聚丙烯基体与乙丙无规共聚物分散相之间的相界面模糊,两相之间的相容性较好.随着聚合物中乙烯含量的增加,分散相出现明显的塑性变形,同时,聚丙烯的结晶形态也发生明显的变化,球晶的尺寸逐渐变小,同时球晶变得不完善. 相似文献
80.
Zifang Zhao Yue Liu Fang Wan Shuai Wang Nannan Zhang Lili Liu Anyuan Cao Zhiqiang Niu 《中国化学快报》2021,32(2):594-597
The recent boom in large-scale energy storage system promotes the development of lithium-oxygen batteries because of their high theo retical energy density.However,their applications are still limited by the sluggish kinetic,insoluble discharge product deposition and the undesired parasitic reaction.Herein,the free-standing nitrogen doped reduced graphene oxide/Co(OH)_2(NRGO/Co(OH)_2) composite films were prepared by a facile hydrothermal method,The NRGO/Co(OH)_2 composite films display interconnected three-dimensional conductive network,which can not only promote the diffusion of O_2 and the transport of electrolyte ions,but also provide abundant storage space for discharge products.Moreover,the introduction of nitrogen-containing functional groups results in improved conductivity and electron adsorption ability,which can facilitate electron transport and enhance the surface catalytic activity.Combining with excellent catalytic performance,the lithium-oxygen batteries with NRGO/Co(OH)_2 composite film cathodes deliver low charge overpotential and excellent cycling performance. 相似文献