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Sensitivity improvement by Vernier effect in microwave photonic filter based on F-P fiber ring

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optoelectronics Letters 2025年

作者： LIN Rui ZHANG Ailing CHANG Pengxiang PAN Honggang WANG Minghe WANG Bo engineering research center of optoelectronic Devices & Communication Technology， Ministry of Education， Tianjin Key Laboratory of Film Electronic and Communication Devices， School of Electrical and Electronic engineering， Tianjin University of Technology

A high sensitivity fiber optic temperature sensor based on Vernier effect in microwave photonic filter based on two paralleled F-P (Fabry-Perot) fiber ring is proposed and experimentally verified. Sensitivity is improved through the Vernier effect， which is caused by two parallel F-P fiber rings with approximate lengths. Temperature interrogation is achieved by monitoring the notch frequency of the superimposed frequency response curve. The temperature sensitivity of -484.514kHz/℃ is achieved in experiment， which is 57 times of the sensor without Vernier effect. The improved sensitivity and simple structure make it have wide potential applications in temperature monitoring of power systems.

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High-selectivity electroreduction of low-concentration CO2 with large concentration fluctuation

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Science China Chemistry 2025年

作者： Mengyu Qi Yanbin Ma Chao Zhang Bingwei Li Xueqing Yang Zhaolin Shi Simeng Liu Changhua An Jiqing Jiao Tongbu Lu MOE International Joint Laboratory of materials Microstructure Analysis and Testing CenterInstitute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringSchool of Chemistry and Chemical EngineeringTianjin University of Technology Key Laboratory of Advanced Energy materials Chemistry (Ministry of Education) Nankai University

Electrochemical CO2reduction reaction（CO2RR） has been regarded as one of the most promising solutions to achieving “zero carbon emission”. In most of the CO2RR-related studies, high-purity CO2has been employed as the feed gas; however, in practice, CO2is generally emitted in low concentrations, so it is of great significance to realize high-selectivity electroreduction of low-concentration CO2with large concentration fluctuation. In this work, we constructed a dual-active-site catalyst and successfully achieved CO2local enrichment and conversion for low-concentration CO2. Operando experiments reveal that the catalyst has one type of site for activating CO2and one type of site for binding the reaction intermediates. The dual-active-site catalyst displays a selectivity for formic acid consistently above 97% over a broad potential window（from-0.9 to-1.6 V ***）. Even when fed with a low-concentration CO2stream（volume ratio from 50% down to 10%）, the dual-active-site catalyst could display high activity and selectivity（>91%）. In particular, the selectivity is still above 85% when the CO2volume ratio is as low as 5%. This work offers a feasible route for converting low-concentration CO2via a synergistic effect for dual-active-site catalysts.

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Metal-organic frameworks (MOFs) in aqueous batteries (ABs):unlocking potential through innovative materials design

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Science China Chemistry 2025年

作者： Bo Han Erhai Hu Bei-Er Jia Ziyang Liu Shuen Tso Afriyanti Sumboja Ivandini T.Anggraningrum Anne Zulfia Syahrial Qingyu Yan SCARCE Laboratory Energy Research Institute NTU (ERIN) Nanyang Technological University School of materials Science and engineering Nanyang Technological University Material Science and engineering research Group Faculty of Mechanical and Aerospace Engineering Institut Teknologi Bandung Department of Chemistry University of Indonesia Metallurgical & materials engineering Department Fakultas Teknik Universitas Indonesia

Metal-organic frameworks (MOFs) represent a revolutionary class of materials in the field of energy storage,particularly for aqueous batteries (ABs).Distinguished by their large surface area,tuneable porosity,and adaptable chemical activity,MOFs offer significant advantages over conventional materials in battery *** article provides a thorough analysis of the crucial role that MOFs play in improving the efficiency of *** includes a concise review of the current research progress,emphasizing the fundamental processes by which MOFs enhance electrochemical ***,the review examines the synthesis and design strategies for the structure of MOFs to maximize ion transport,improve conductivity,and enhance *** structural advantages,chemical versatility,stability,durability and functionalization potential of MOFs are comprehensively ***,we explore the distinct advantages of MOFs in overcoming common challenges encountered in ABs,such as declining capacity,inadequate cycling stability,and limited energy *** paper also highlights the future research directions needed to fully harness their *** goal is to develop a fundamental understanding and stimulate further progress in the use of MOFs for advanced energy storage solutions.

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engineering atomic Rb-N configurations to tune radical pathways for highly selective photocatalytic H2O2 synthesis coupled with biomass valorization

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Journal of Energy Chemistry 2025年第1期100卷 215-225页

作者： Jiaye Li Shuang Pan Yihuang Chen Qiong Liu College of Chemistry and materials engineering Wenzhou University Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology (China) Institute of Analysis Guangdong Academy of Sciences (China National Analytical CenterGuangzhou)

Photocatalytic oxygen reduction for hydrogen peroxide （H2O2） synthesis presents a green and costeffective production ***,achieving highly selective H2O2synthesis remains challenging,necessitating precise control over free radical reaction pathways and minimizing undesirable oxidative ***,we report for the visible light-driven simultaneous co-photocatalytic reduction of O2to H2O2and oxidation of biomass using the atomic rubidium-nitride modified carbon nitride（CNRb）.The optimized CNRb catalyst demonstrates a record photoreduction rate of 8.01 mM h-1for H2O2generation and photooxidation rate of 3.75 mM h-1for furfuryl alcohol to furoic acid,achieving a remarkable solar-to-chemical conversion （SCC） efficiency of up to 2.27%.Experimental characterizations and DFT calculation disclosed that the introducing atomic Rb–N configurations allows for the high-selective generation of superoxide radicals while suppressing hydroxyl free radical *** is because the Rb–N serves as the new alternative site to perceive a stronger connection position for O2adsorption and reinforce the capability to extract protons,thereby triggering a high selective redox product *** study holds great potential in precisely regulating reactive radical processes at the atomic level,thereby paving the way for efficient synthesis of H2O2coupled with biomass valorization.

关键词： Free radical reactions

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo Zhang Jie Dang Jia Guo Hanghang Zhou Xuewei Lü College of materials Science and engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

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Locally Enhanced Flow and Electric Fields Through a Tip Effect for Efficient Flow‑Electrode Capacitive Deionization

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Nano-Micro Letters 2025年第2期17卷 1-17页

作者： Ziquan Wang Xiangfeng Chen Yuan Zhang Jie Ma Zhiqun Lin Amor Abdelkader Maria‑Magdalena Titirici Libo Deng College of Chemistry and Environmental engineering Shenzhen UniversityShenzhen 518060People’s Republic of China research center for Environmental functional materials College of Environmental Science and EngineeringTongji University1239 Siping RoadShanghai 200092People’s Republic of China Department of Chemical and Biomolecular engineering National University of SingaporeSingapore 117585Singapore Department of engineering Faculty of Science and TechnologyBournemouth UniversityTalbot CampusFern BarrowPooleEngland BH125BBUK Institut de Chimie de Nice UniversitéCôte d’AzurUMR CNRS 727228 Av.Valrose06108 NiceFrance Department of Chemical engineering Imperial College LondonSouth Kensington CampusExhibition RdLondon SW72AZUK

Low-electrode capacitive deionization(FCDI)is an emerging desalination technology with great potential for removal and/or recycling ions from a range of ***,it still suffers from inefficient charge transfer and ion transport kinetics due to weak turbulence and low electric intensity in flow electrodes,both restricted by the current ***,a new tip-array current collector(designated as T-CC)was developed to replace the conventional planar current collectors,which intensifies both the charge transfer and ion transport *** effects of tip arrays on flow and electric fields were studied by both computational simulations and electrochemical impedance spectroscopy,which revealed the reduction of ion transport barrier,charge transport barrier and internal *** the voltage increased from 1.0 to 1.5 and 2.0 V,the T-CC-based FCDI system(T-FCDI)exhibited average salt removal rates(ASRR)of 0.18,0.50,and 0.89μmol cm^(-2) min^(-1),respectively,which are 1.82,2.65,and 2.48 folds higher than that of the conventional serpentine current collectors,and 1.48,1.67,and 1.49 folds higher than that of the planar current ***,with the solid content in flow electrodes increased from 1 to 5 wt%,the ASRR for T-FCDI increased from 0.29 to 0.50μmol cm^(-2) min^(-1),which are 1.70 and 1.67 folds higher than that of the planar current ***,a salt removal efficiency of 99.89%was achieved with T-FCDI and the charge efficiency remained above 95%after 24 h of operation,thus showing its superior long-term stability.

关键词： Flow-electrode Capacitive deionization Current collector Tip effect Desalination

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A triple-band miniaturized end-fire antenna based on odd-mode spoof surface plasmonic polariton waveguide resonator

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optoelectronics Letters 2025年

作者： BAI Yukun MAO Mengqun Tianjin Key Laboratory of Film Electronic and Communication Devices， engineering research center of optoelectronic Devices and Communication Technology， Ministry of Education， School of Integrated Circuit Science and engineering， Tianjin University of Technology

A triple-band miniaturized end-fire antenna based on the odd modes of spoof surface plasmonic polariton (SSPP) waveguide resonator is proposed in this paper. To meet the ever increasing demand for more communication channels and less antenna sizes， multi-band antennas are currently under intensive investigation. By a novel feeding method， three odd modes are excited on an SSPP waveguide resonator， which performs as an end-fire antenna operating at three bands， 7.15-7.26GHz， 11.6-12.2GHz and 13.5-13.64GHz. It exhibits reasonably high and stable maximum gains of 5.26， 7.97 and 10.1dBi and maximum efficiencies of 64%， 92% and 98% at the three bands， respectively. Moreover， in the second band the main beam angle shows a frequency dependence with a total scanning angle of 19°. The miniaturized triple-band antenna has a great potential to be applied in wireless communication systems， satellite communication and radar systems.

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Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期68卷 249-256页

作者： Qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian Zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

关键词： gold catalysis peptide alkylation C-C coupling radical

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Modification of Maxwell model for conductivity prediction of carbon nanotubes-filled polymer composites with tunneling effect

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 25-36页

作者： Jue ZHU Longyuan LI Ningtao ZHU Zhejiang Provincial engineering research center for the Safety of Pressure Vessel and Pipeline Key Laboratory of Impact and Safety engineering (Ningbo University) Ministry of Education School of engineering Computing and Mathematics University of Plymouth Xi'an Zhanshi Testing & engineering Co.Ltd.

Carbon nanotubes(CNTs) have garnered great attention in recent years due to their outstanding electrical, thermal, and mechanical properties. The incorporation of small amounts of CNTs in polymers can substantially improve the sensitivity of the polymer's electrical conductivity. This paper presents a modified Maxwell model to evaluate the electrical conductivity of CNTs-filled polymer composites by introducing a transition zone to account for the tunneling effect. In this modified Maxwell model, the CNTs-filled polymer composite is modeled as a three-phase composite, consisting of a matrix(polymer), inclusions(CNTs), and a transition zone(tunneling zone). The effective electrical conductivity(EEC) of the composite is calculated based on the volume fractions and electrical conductivities of the matrix, inclusions, and transition zone. The model's validity is confirmed through the use of available test data, which demonstrates its capability to accurately capture the nonlinear conductivity behavior observed in CNTs-polymer composites. This study offers valuable insights into the design of high-performance conductive polymer nanocomposites, and enhances the understanding of electrical conduction mechanisms in CNT-dispersed polymer composites.

关键词： Nanoclay