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1.
以有序介孔碳(OMC)球为离子-电子转换层,制备了固态氯离子选择性电极,构建了基于离子敏感的场效应晶体管(ISFET)的手持式传感系统,用于检测人体血清中的氯离子。优化了OMC前驱体的碳化温度,探究了OMC形貌结构对电极传感性能的影响;电极柔性化制备后考察了其在手持系统中对氯离子的检测效果。结果表明,最优条件下,电极在5.12×10^-4~1.02 mol/L的浓度范围呈现线性响应,响应斜率为60 mV/decade。该柔性电极在手持传感系统中展现出高灵敏度和重现性,可用于人体血清样品中氯离子的检测,其回收率为96.3%~104.9%。 相似文献
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《Physics letters. A》2020,384(23):126556
Vibration characteristics of elastic nanostructures embedded in fluid medium have been used for biological and mechanical sensing, and also to investigate materials mechanical properties. An analytical approach based on the exact theory has been developed in this paper, to establish a new accurate and simple generalized frequency equation to predict spheroidal vibration of an elastic nanosphere, in a compressible viscoelastic fluid using linear Maxwell fluid model. To demonstrate the accuracy of the present approach, a comparison is made with the published theoretical results in the literature in some particular cases, which shows a very good agreement. Thus, the obtained frequency equation can be very useful to interpret the experimental measurements of vibrational dynamics of nanospheres and can serve as benchmark solution in design of liquid sensors. 相似文献
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Dr. Qiuhua Liu Wanjie Ren Siwei Zhang Dr. Yang Huang Dilong Chen Dr. Wennan Zeng Prof. Dr. Zaichun Zhou Prof. Dr. Lin He Prof. Dr. Wenping Guo Prof. Dr. Jianfeng Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(8):e202103892
Both geometric architecture and electronic configurations of heme proteins contribute to its activity. In this work we designed and synthesized a series of four copper(II) porphyrin complexes ( 4 -, 3 -, 2 - and 1 -Cu) where the molecular conformations are modulated by a pair of stepwise shortened straps on the same porphyrin side (cis-ortho) to give double bow-shaped skeletons. Single crystal structures demonstrate that the straps gradually increase the saddle deformation and the deviation of the metal centers, which is in accordance with two, unusual d-orbital reconstructions of two different ground states, as revealed by 4 K EPR and DFT calculations. In the study of the electrocatalytic hydrogen evolution reaction (HER), 1 -Cu, with the shortest straps, showed the most apparent improvement of activity. Second coordination sphere (SCS) effects created by the double bow-shaped architecture and the strong saddle porphyrin core in 1 -Cu are found to play key roles in proton trapping during the catalytic process. The work contributes a novel strategy to improve the catalytic performance of heme analogs through ligand geometric modulation. 相似文献
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《化学:亚洲杂志》2017,12(24):3203-3207
The self‐assembly process of a Pd12L24 sphere was revealed by a quantitative approach (quantitative analysis of self‐assembly process: QASAP) quantifying all the substrates, the products, and the observable intermediates, indicating that the Pd12L24 sphere is produced through several pathways. Firstly, Pdn L2n (n= 6, 8, and 9), which are perfectly closed structures smaller than the Pd12L24 sphere, and a mixture of intermediates not observed by NMR ( Int ) were produced. Next, the sphere was assembled from intra‐/intermolecular reaction of a certain class of Int (path A) and from the coordination of free pyridyl groups in Int to the PdII center of Pdn L2n (n= 6, 8, and 9) (path B). While capping the free pyridyl groups in Int with PdII ions perfectly inhibited the sphere formation, the addition of free L to Int accelerated the formation of the sphere. 相似文献
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介绍了Rieffel定义的紧致量子度量空间与量子Gromov-Hausdorff距离和近来Latrémolière定义的量子Gromov-Hausdorff邻距,分别讨论了矩阵代数如何在这两种量子距离下收敛至球面. 相似文献
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Hanchul PARK 《数学年刊B辑(英文版)》2017,38(6):1321-1334
This paper deals with two things.First,the cohomology of canonical extensions of real topological toric manifolds is computed when coefficient ring G is a commutative ring in which 2 is unit in G.Second,the author focuses on a specific canonical extensions called doublings and presents their various properties.They include existence of infinitely many real topological toric manifolds admitting complex structures,and a way to construct infinitely many real toric manifolds which have an odd torsion in their cohomology groups.Moreover,some questions about real topological toric manifolds related to Halperin's toral rank conjecture are presented. 相似文献
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In this paper, we investigate isometric extension problem in general normed space. We prove that an isometry between spheres can be extended to a linear isometry between the spaces if and only if the natural positive homogeneous extension is additive on spheres. Moreover, this conclusion still holds provided that the additivity holds on a restricted domain of spheres. 相似文献