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Ultrasensitive electrochemical sensor for luteolin based on MOFs-derived metal oxide/alloy-doped nitrogen-containing porous carbon composites

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Talanta 2025年 296卷 128359页

作者： Jiejun Li Liang Wang Caiyu Ge Zuwen Zheng Yijing Wang Pengcheng Zhao Junjie Fei Yixi Xie Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education Xiangtan University Xiangtan 411105 People's Republic of China. Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education Xiangtan University Xiangtan 411105 People's Republic of China Hunan Institute of Advanced Sensing and Information Technology Xiangtan University Xiangtan 411105 People's Republic of China. Hunan Institute of Advanced Sensing and Information Technology Xiangtan University Xiangtan 411105 People's Republic of China. Electronic address: fei_junjie@***. Key Laboratory for Green Organic Synthesis and Application of Hunan Province Xiangtan University Xiangtan 411105 People's Republic of China. Electronic address: xieyixige@***.

As a natural flavonoid with diverse pharmacological activities, luteolin has shown attractive potential in various applications such as drug discovery, food preservation, health care products, and cosmetics. The precise quantification of luteolin is not only crucial for optimizing its therapeutic efficacy, but also for ensuring compliance with safety standards, as its biological activity largely depends on concentration thresholds and excessive intake may lead to adverse reactions. Here, we have successfully developed an electrochemical sensing platform for luteolin using a simple synthesis strategy. The core of this platform lies in the composite of metal oxides/alloys and nitrogen-doped porous carbon obtained after pyrolysis, whose unique porous architecture and rich pyrrolic nitrogen structure provide efficient adsorption sites for luteolin, while the diverse active centers embedded in the composite significantly enhance its electrocatalytic efficacy. The carefully constructed FeCo-NC-800/GCE electrochemical sensing platform exhibits excellent performance in detecting luteolin. More importantly, we have successfully applied this sensing platform to the detection of luteolin in actual samples such as peanut shells, honeysuckle, and chrysanthemum, which verified the accurate identification of luteolin by FeCo-NC-800/GCE in complex environmental backgrounds and demonstrated its great potential in practical applications.

关键词： Bimetallic Electrochemical sensor Food analysis Luteolin

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Research on the Fire Hose Burst Issues in the Stator of The Hydraulic Power Plant

Research on the Fire Hose Burst Issues in the Stator of The ...

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International Conference on Mechanical, Control and Computer Engineering (ICMCCE)

作者： Dun Mao Lanlan Liu Wenbo Li Jiran Zhu Junjun Chen Chongwang Tang State Grid Hunan Transmission Maintenance Company Changsha China Hunan Province Key Laboratory of Intelligent Live Working Technology and Equipment (Robot) Live Inspection and Intelligent Operation Technology State Grid Corporation Laboratory Changsha China State Grid Hunan Electric Power Company Limited Research Institute Changsha China

The safety issue of technical water supply pipelines in hydroelectric power plant has been an ingrained problem, especially for the old hydraulic power plants. On the one hand, the original design and manufacture are inferior in quality; on the other hand, as the corrosion aggravates over time, water leakage and seepage frequently arise. In acute cases, the workshop may be flooded and other major accidents may occur accordingly. Starting with an accident that the fire hose of stator broke apart, this paper analysed the causes for pipeline break and presented relevant rectification scheme. It has provided technical guidance for maintaining and reconditioning the same type of water pipes.

关键词： Hoses Corrosion Conferences Pipelines Hydroelectric power generation Hydraulic systems Stators

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Molecular tailoring towards two-dimensional organic crystals at the thickness limit

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Chinese Chemical Letters 2024年

作者： Zhilei Zhang Yanan Sun Xiaosong Shi Xiaozhe Yin Dawei Liu Erjing Wang Jie Liu Yuanyuan Hu Lang Jiang Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of the Chinese Academy of Sciences Beijing 100049 China Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional Materials Faculty of Materials Science and Engineering Hubei University Wuhan 430062 China Key Laboratory for Micro/Nano Optoelectronic Devices of Ministry of Education & International Science and Technology Innovation Cooperation Base for Advanced Display Technologies of Hunan Province School of Physics and Electronics Hunan University Changsha 410082 China

Advances in controllable growth of ultrathin two-dimensional molecular crystals (2DMCs) or even monolayer molecular crystals (MMCs) propelled their application in high-performance, high-sensitivity, low-contact-resistance optoelectronic devices. However, the rational molecular design strategies for materials prone to grow into ultrathin 2DMC or MMC have rarely been addressed. Here, systematically tailoring the π -conjugation and alkyl chain types of asymmetric anthracene derivatives, 2DMCs and even MMCs were obtained under the synergetic regulation of inter- and intralayer interactions. High-quality MMCs were obtained for SAP-C6 by traditional physical vapor transport technique (PVT), and corresponding organic field-effect transistors (OFETs) exhibited high mobility of 3.22 cm 2 V -1 s -1 . In addition, band-like charge transport with low activation energy was achieved by SAP-C6 MMC-OFETs. Furthermore, the SAP-C6 MMC-based device exhibits excellent thermal stability, retaining ∼70% of its initial performance at 140°C in air, which is the first report on the thermal stability of MMC devices. This research highlights the potential of alkyl-substituted asymmetric molecules as a design strategy to achieve ultrathin 2DMC or MMC growth, and improve the mobility and thermal stability in OFETs.

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5,18-Dimesitylorangarin: a Stable Antiaromatic Pentaphyrin(1.0.1.0.0) Displaying Remarkable Oxidative Self-Coupling Reactions

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Angewandte Chemie 2024年第38期136卷

作者： Dr. Yutao Rao Jiyeon Lee Jinchao Chen Prof. Dr. Ling Xu Prof. Dr. Mingbo Zhou Dr. Bangshao Yin Prof. Dr. Jiwon Kim Prof. Dr. Atsuhiro Osuka Prof. Dr. Jianxin Song Key Laboratory of Chemical Biology and Traditional Chinese Medicine Ministry of Educational of China Key Laboratory of the Assembly and Application of Organic Functional Molecules of Hunan Province College of Chemistry and Chemical Engineering Hunan Normal University Changsha 410081 China School of Integrated Technology College of Computing Yonsei University Incheon 21983 Republic of Korea Integrated Science and Engineering Division Underwood International College Yonsei University Incheon 21983 Republic of Korea Integrative Biotechnology and Translational Medicine Graduate School Yonsei University Incheon 21983 Republic of Korea

5,18-Dimesitylorangarin and its BF 2 complex were synthesized by double S N Ar reaction of 3,5-dibromo-BODIPY with 2-pyrrolydipyrrin as the first examples of meso -aryl-substituted orangarin. These orangarins, delineated as [20]pentaphyrin(1.0.1.0.0), are strongly antiaromatic but rather stable. The free base orangarin was coupled by oxidation with MnO 2 to give a 11,11′-linked dimer, a cyclooctatetraene(COT)-centered trimer, and a spiro-trimer. Fused COT-centered 3H -orangarin dimer was oxidized to the corresponding 2H -orangarin dimer, which was further coupled to give a triply COT-centered 2H -orangarin tetramer. 3 H -Orangarin oligomers are all antiaromatic as evinced by extremely low-field-shifted 1 H NMR signals of the inner NH and ill-defined absorption spectra with broad tails. In contrast, COT-centered 2 H -orangarin dimer and tetramer show moderately low-field-shifted NH signals and intense NIR absorbance over 900 nm, suggesting effective π-conjugation through the COT bridge and almost non-antiaromatic character. These orangarin oligomers exhibit many reversible redox potentials owing to the intramolecular electronic interactions. Regardless of the different aromatic characters, all the orangarin monomers and oligomers exhibit very rapid excited-state decays.

关键词： pentaphyrin orangarin antiaromaticity oligomerization cyclooctatetraene

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Research on the Surface Overlay Quality Problems of the Hubs in Axial-Flow Assembling Unit During Ex-Factory Acceptance

Research on the Surface Overlay Quality Problems of the Hubs...

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International Conference on Mechanical, Control and Computer Engineering (ICMCCE)

作者： Dun Mao Lanlan Liu Wenbo Li Jiran Zhu Junjun Chen Chongwang Tang State Grid Hunan Transmission Maintenance Company Changsha China Hunan Province Key Laboratory of Intelligent Live WorkingTechnology and Equipment (Robot) Live Inspection and Intelligent Operation Technology State Grid Corporation Laboratory Changsha China State Grid Hunan Electric Power Company Limited Research Institute Changsha China

ISBN: (纸本)9781665423144;9781665446235

The casting material of modified hub in a certain assembling unit was made from 20SiMn Furthermore, it used the puddle welding technology to generate 390L cladding as the surface of hub to improve its anti-cavitation ability. Nevertheless, quality issues were still spotted on the overlay of hubs in ex-factory acceptance. On the one hand, the detecting defects existed in the penetration test; on the other hand, the hardness test was ineligible. After turning off the defective surface, the inner puddle welding layer remained similar defects. Therefore, the surface overlay of hubs was completely turned off and then processed by puddle welding method so as to ensure the overall quality of the hubs.

关键词： Casting Welding Turning Surface treatment

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A Study on the Differences of Attitude Learning and Learning Behavior Sequences for University Computer MOOC+ SPOC Course

A Study on the Differences of Attitude Learning and Learning...

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International Conference on Computer Science & Education (ICCSE)

作者： Zhao Changhua Mi Chunqiao School of Computer Science and Engineering Huaihua University Huaihua P. R. China Key Laboratory of Wuling-Mountain Health Big Data Intelligent Processing and Application in Hunan Province Universities Huaihua P. R. China Key Laboratory of Intelligent Control Technology for Wuling-Mountain Ecological Agriculture in Hunan Province Huaihua P. R. China

ISBN: (数字)9781728172675

ISBN: (纸本)9781728172682

The outbreak of COVID-19 make University Computer MOOC+SPOC course face opportunities and challenges. There are some problems in MOOC+SPOC course teaching, such as learners' curiosity decreasing, lack of accomplishment and etc. In order to deal with these problems, this study explores the correlation and differences in the learning behavior sequences of learners with different attitudes to high happiness, medium happiness, and low happiness. Through the learners' comments on University Computer MOOC+SPOC course, the learner's attitude information is tapped. By analyzing learning behavior sequences, this study finds out the degree of learning behavior change of learners with different attitudes. The result of this study can improve the existing University Computer MOOC+SPOC instructional design and promote the learning mode to move towards intelligent personalized adaptive learning.

关键词： Interviews Electronic learning Data analysis Encoding Correlation

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A Carbene Relay Strategy for Cascade Insertion Reactions

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Angewandte Chemie 2023年第45期135卷

作者： Li Li Chenggang Mi Guanwang Huang Meirong Huang Yuyi Zhu Shao-Fei Ni Zhaofeng Wang Yong Huang Department of Chemistry The Hong Kong University of Science and Technology Clear Water Bay Kowloon Hong Kong SAR China State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha Hunan 410082 China Shenzhen Bay Laboratory Shenzhen 518132 China Laboratory of Computational Chemistry and Drug Design State Key Laboratory of Chemical Oncogenomics Peking University Shenzhen Graduate School Shenzhen 518055 China Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong Province Shantou University Shantou Guangdong 515063 China

Insertion reactions that involve stabilized electrophilic metallocarbenes are of great importance for installing α-heteroatoms to carbonyl compounds. Nevertheless, the limited availability of carbene precursors restricts the introduction of only a single heteroatom. In this report, we describe a new approach based on an I (III) /S (VI) reagent that promotes the cascade insertion of heteroatoms. This is achieved by sequentially generating two α-heteroatom-substituted metal carbenes in one reaction. We found that this mixed I (III) /S (VI) ylide reacts efficiently with a transition metal catalyst and an X−H bond (where X=O, N). This transformation leads to the sequential formation of a sulfoxonium- and an X-substituted Rh-carbenes, enabling further reactions with another Y−H bond. Remarkably, a wide range of symmetrical and unsymmetrical α,α- O , O -, α,α- O , N -, and α,α- N , N -subsituted ketones can be prepared under mild ambient conditions. In addition, we successfully demonstrated other cascades, such as CN/CN double amidation, C−H/C−S double insertion, and C−S/Y−H double insertion (where Y=S, N, O, C). Notably, the latter two cascades enabled the simultaneous installation of three functional groups to the α-carbon of carbonyl compounds in a single step. These reactions demonstrate the versatility of our approach, allowing for the synthesis of ketones and esters with multiple α-heteroatoms using a common precursor.

关键词： Carbene Relay Fischer Carbene Heteroatom-Substituted Carbene Insertion Reaction Ketal Synthesis

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Polarity-induced electronic and atomic reconstruction at NdNiO2/SrTiO3 interfaces

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Physical Review B 2020年第3期102卷 035118-035118页

作者： Ri He Peiheng Jiang Yi Lu Yidao Song Mingxing Chen Mingliang Jin Lingling Shui Zhicheng Zhong School of Information and Optoelectronic Science and Engineering South China Normal University Guangzhou 510006 China Key Laboratory of Magnetic Materials Devices & Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences Ningbo 315201 China International Academy of Optoelectronics at Zhaoqing South China Normal University Zhaoqing 526238 China Institute for Theoretical Physics University of Heidelberg Heidelberg 69120 Germany School of Physics and Electronics Hunan Normal University Key Laboratory for Matter Microstructure and Function of Hunan Province Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Changsha 410081 China China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing 100049 China

Superconductivity has recently been observed in Sr-doped NdNiO2 films grown on SrTiO3. Whether it is caused by or related to the interface remains an open question. To address this issue, we use density-functional theory calculation and charge-transfer self-consistent model to study the effects of polar discontinuity on the electronic and atomic reconstruction at the NdNiO2/SrTiO3 interface. We find that sharp interface with pure electronic reconstruction only is energetically unfavorable, and atomic reconstruction is unavoidable. We further propose a possible interface configuration that contain residual apical oxygen. These oxygen atoms lead to hybrids of dz2 and dx2−y2 states at the Fermi level, which weaken the single-band feature and may be detrimental to superconductivity.

关键词： Electronic structure Superconductivity Superconductors Transition metal oxides First-principles calculations

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Reverse-engineering bar charts using neural networks

arXiv

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arXiv 2020年

作者： Zhou, Fangfang Zhao, Yong Chen, Wenjiang Tan, Yijing Xu, Yaqi Chen, Yi Liu, Chao Zhao, Ying School of Computer Science and Engineer Central South University Changsha China Beijing Key Laboratory of Big Data Technology for Food Safety Beijing Technology and Business University Beijing China Institute of Systems Engineering Academy of Military Sciences Beijing China Rail Data Research and Application Key Laboratory of Hunan Province Changsha China

Reverse-engineering bar charts extracts textual and numeric information from the visual representations of bar charts to support application scenarios that require the underlying information. In this paper, we propose a neural network-based method for reverse-engineering bar charts. We adopt a neural network-based object detection model to simultaneously localize and classify textual information. This approach improves the efficiency of textual information extraction. We design an encoder–decoder framework that integrates convolutional and recurrent neural networks to extract numeric information. We further introduce an attention mechanism into the framework to achieve high accuracy and robustness. Synthetic and real-world datasets are used to evaluate the effectiveness of the method. To the best of our knowledge, this work takes the lead in constructing a complete neural network-based method of reverse-engineering bar charts. Copyright © 2020, The Authors. All rights reserved.

关键词： Reverse engineering

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Enhanced Electricity Generation and H2O2 Production in a Photocatalytic Fuel Cell and Fenton Hybrid System Assisted with Reverse Electrodialysis

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ACS omega 2019年第3期4卷 5848-5851页

作者： Peng Xu Hao Xu Key Laboratory for Green & Advanced Civil Engineering Materials and Application Technology of Hunan province and College of Civil Engineering Hunan University Changsha 410082 China.

A novel integrating system coupled with photocatalytic fuel cell and Fenton system assisted by reverse electrodialysis (PREC) is proposed. The results demonstrate that HO concentration increased continuously in the reaction process to finally reach 960 mg/L and the current became stable at around 5.2 mA. The salinity-driven potential derived from the high concentration and low concentration cells in the hybrid system was 0.72 and 0.90 V respectively, at the salinity ratio of 50 and 100. The hybrid system has an energy recovery of 16%, a cathodic efficiency of 51%, and the maximum power of 76 W/m at a salinity ratio of 50, with a 100 Ω external resistance. It is proved that PREC-Fenton possessed great potential in industrial wastewater treatment.

关键词： Electrochemical cells Energy Power Electrodes Membranes

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