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Convenient and Efficient Reaction System for the Oxidative Coupling of Terminal Alkynes Over Cu+-Containing Layered Double Hydroxides

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SSRN 2022年

作者： Cui, Wenlong Zhao, Chenze Cao, Shanshan Zhu, Qingqing Wang, Cheli Zheng, Yingxing Zhou, Weiyou Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology Changzhou University Changzhou213164 China

An efficient and convenient catalytic procedure has been developed for the aerobic oxidative coupling of terminal alkynes to produce 1,3-conjugated diynes over CuCoFe-LDH (Layered double hydroxide) in the absence of base additive. The heterogeneous catalytic system could tolerate various arylacetylenes in good to excellent yields. The results indicated that Cu+ species in CuCoFe-LDH should play the predominant role in the transformation, and dual functions of the catalyst were observed. The CuCoFe-LDH also showed good structural and catalytical stability during the reactions. © 2022, The Authors. All rights reserved.

关键词： Molecular oxygen

Topological Degeneracy Induced by Twisting

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Physical Review Letters 2025年第10期134卷 106601-106601页

作者： Han Peng Qiang Wang Meng Xiao Xiayi Wang Shining Zhu Hui Liu National Laboratory of Solid State Microstructures Jiangsu Physical Science Research Center School of Physics Collaborative Innovation Center of Advanced Microstructures Nanjing University Nanjing 210093 China Key Laboratory of Artificial Micro- and Nano-structures of Ministry of Education and School of Physics and Technology Wuhan University 430072 Wuhan China Wuhan Institute of Quantum Technology Wuhan 430206 China

In recent years, twisting has emerged as a new degree of freedom that plays an increasingly important role in Bloch bands of various physical systems. However, there is currently a lack of reports on the nontrivial physics of topological degeneracy in twisted systems. In this Letter, we investigated the intrinsic physical correlation between twisting and topological degeneracy. We found that twisting not only breaks the symmetry of the system but also introduces topological degeneracy that does not exist under the original symmetric system without twisting. Furthermore, the topological degeneracy can be easily tuned through twisting. This new twist-induced topological degeneracy gives rise to a unique polarization-degenerate birefringent medium, wherein the twist angle acts as a novel degree of freedom for dispersion and polarization management of interface states. Exhibiting fascinating properties and experimental feasibilities, our Letter points to new possibilities in the research of various topological physics in twisted photonics.

关键词： Polarization

Ultra-thin CoAl layered double hydroxide nanosheets for the construction of highly sensitive and selective QCM humidity sensor

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Chinese Chemical Letters 2023年第8期34卷 376-381页

作者： Yongheng Zhu Xuhua Dong Jinsheng Cheng Lumin Wang Cheng Zhao Yonghui Deng Siqi Xie Yingjie Pan Yong Zhao Gengzhi Sun Tianjun Ni College of Food Science and Technology Laboratory of Quality&Safety Risk Assessment for Aquatic Products on Storage and Preservation(Shanghai)Ministry of Agriculture and Shanghai Engineering Research Center of Aquatic-Product Processing&Preservation Shanghai Ocean UniversityShanghai 201306China School of Basic Medicine Xinxiang Medical UniversityXinxiang 453003China Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing Tech University(NanjingTech)Nanjing 211816China Department of Chemistry FudanUniversityShanghai 200433China Henry-Fork School of Food Sciences Shaoguan UniversityShaoguan 512005China

To achieve real-time monitoring of humidity in various applications,we prepared facile and ultra-thin CoAl layered double hydroxide(CoAl LDH)nanosheets to engineer quartz crystal microbalances(QCM).The characteristics of CoAl LDH were investigated by transmission electron microscopy(TEM),X-ray diffraction(XRD),X-ray photoelectric spectroscopy(XPS),Brunauer–Emmett–Telle(BET),atomic force microscopy(AFM)and zeta *** to their large specific surface area and abundant hydroxyl groups,CoAl LDH nanosheets exhibit good humidity sensing *** a range of 11.3%and 97.6%relative humidity(RH),the sensor behaved an ultrahigh sensitivity(127.8 Hz/%RH),fast response(9.1 s)and recovery time(3.1 s),low hysteresis(3.1%RH),good linearity(R^(2)=0.9993),stability and ***,the sensor can recover the initial response frequency after being wetted by deionized water,revealing superior self-recovery ability under high *** on in-situ Fourier transform infrared spectroscopy(FT-IR),the adsorption mechanism of CoAl LDH toward water molecules was *** QCM sensor can distinguish different respiratory states of people and wetting degree of fingers,as well as monitor the humidity in vegetable packaging,suggesting excellent properties and a promising application in humidity sensing.

关键词： Layered double hydroxide nanosheets Quartz crystal microbalance Humidity sensor Respiratory monitoring Sensing mechanism

An efficient chemical reduction-induced assembly of Fe_(3)O_(4)@graphene fiber for wire-shaped supercapacitors with ultrahigh volumetric energy density

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Science China(Technological Sciences) 2021年第10期64卷 2246-2254页

作者： XIAO Peng SHI MinJie XU Li TAO FengBo LI Yu ZHU HangTian LIU YuTing LI ZhiMin ZHOU YunPeng FENG Wei State Grid Jiangsu Electric Power Co.Ltd.Research Institute Nanjing 211103China School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China State Key Laboratory of Advanced Transmission Technology Global Energy Interconnection Research Institute Co.Ltd.Beijing 102211China School of Materials Science and Engineering Tianjin UniversityTianjin 300354China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215213China

Benefiting from high flexibility and weavability,the wire-shaped supercapacitors(SCs)arouse tremendous interests for the applications in wearable/portable *** fiber(GF)is considered as a promising linear electrode for wire-shaped ***,the bottleneck is how to develop the GF-based linear electrode with facile fabrication process while wellmaintaining satisfactory electrochemical ***,a novel Fe_(3)O_(4)@GF composite linear electrode is proposed via a chemical reduction-induced assembly approach,in which the GO and Fe_(3)O_(4) nanoparticles(NPs)realize the efficient selfassembly owing to the electrostatic and van der Waals interactions,as well as the sufficient reduction of GO during the preparation *** resultant fiber-shaped architecture shows boosted charge-transfer kinetics,high flexibility and structural *** Fe_(3)O_(4)@GF linear electrode exhibits excellent electrochemical behaviors including a large volumetric specific capacitance(~250.75 F cm^(−3)),remarkable rate capability and favorable electrochemical kinetics in aqueous electrolyte,superior than previously reported GF-based linear *** real application,a high-performance wire-shaped SC with excellent flexibility and weavability is fabricated based on such Fe_(3)O_(4)@GF linear electrode and gel electrolyte,demonstrating ultrahigh volumetric energy density(18.8 mWh cm^(−3)),power density(4000 mW cm^(−3))and strong durability(~93.5%retention after 10000 cycles).Prospectively,the fabricated wire-shaped SC can maintain reliable electrochemical behaviors in various deformation states,showing its potentials in future portable and wearable devices.

关键词： wire-shaped supercapacitors self-assembly graphene fiber high energy density wearable electronics

Insight into the Mechanism of Gradient Fine Grains for Super Combination of Strength and Ductility

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SSRN 2023年

作者： Mao, Xiangyang Su, Guoquan Zhang, Chuhan Liang, Xiaoxiao Wang, Wei Qi, Cheng School of Materials Science and Engineering Nanjing Institute of Technology Nanjing211167 China Jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing211167 China

The gradient fine grains on low-carbon steel surface were produced via ultrasonic impact treatment, which led to super combination of high strength and ductility. The underlying mechanism was studied with tensile deformation testing and microstructure analysis. Results of the study showed that the grain size had a gradient increasing from 120nm at top surface to 5~8μm inside the bulk, determined by EBSD and TEM. In the gradient fine grain region, the angle of grain boundary is generally low, in the range of 2~15°. Compared with original microstructure, the surface gradient fine gains can achieve a higher work hardening rate, and has the lower ee-p values of 7.5%. A DIC technology was employed to analyze variations in strain during the tensile deformation. It is demonstrated that the surface gradient distribution of grain size can reduce the stress concentration, resulting in higher resistance to uneven deformation. Such a capability is attributed to the decreased dislocation density and Schimidt factor due to gradient fine gain distribution during tensile deformation. Compared with the original microstructure, a number of dislocation walls (or cells, or clusters) induced by tensile deformation can hinder the movement of dislocations. In addition, the surface gradient fine grains have faster recovery and proliferation of movable dislocation density, which can lead to higher work-hardening ability. As a result, the surface gradient fine grains can attain a combination of excellent strength and *** gradient fine grains on low-carbon steel surface were produced via ultrasonic impact treatment, which led to super combination of high strength and ductility. The underlying mechanism was studied with tensile deformation testing and microstructure analysis. Results of the study showed that the grain size had a gradient increasing from 120nm at top surface to 5~8μm inside the bulk, determined by EBSD and TEM. In the gradient fine grain region, the angle of grain bou

关键词： Microstructure

EMG Based Rehabilitation Gesture Recognition Using DAE-CNN-LSTM Hybrid Model

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EMG Based Rehabilitation Gesture Recognition Using DAE-CNN-L...

World Rehabilitation Robot Convention (WRRC)

作者： Wujing Cao Xinqiang Guo Yupeng Zou Shuo Zhang Mingxiang Luo Worawarit Kobsiriphat Xinyu Wu Meng Yin Guangdong Provincial Key Lab of Robotics and Intelligent System Shenzhen Institute of Advanced Technology Chinese Academy of Sciences Shenzhen China SIAT-CUHK Joint Laboratory of Robotics and Intelligent Systems SIAT Branch Shenzhen Institute of Artificial Intelligence and Robotics for Society School of Mechanical Engineering China University of Petroleum East China National Metal and Materials Technology Center Thailand

ISBN: (数字)9798350355123

ISBN: (纸本)9798350355130

Stroke, as one of the leading causes of long-term disability globally, often results in motor impairments, particularly in the hands, significantly affecting patients' daily activities and causing profound psychological trauma. Rehabilitation gesture recognition, as one of the key means of active rehabilitation medicine, holds significant potential in stroke rehabilitation, providing real-time feedback on patient progress and enabling personalized interventions to meet individual needs. Traditional gesture recognition methods face numerous challenges when dealing with stroke patient data, such as noise, motion blur, and individual differences. To address these challenges, this paper proposes a novel approach for stroke patient gesture recognition using deep learning models. We adopt a strategy combining denoising autoencoder (DAE), convolutional neural network (CNN), and long short-term memory (LSTM) to enhance the accurate recognition of hand movements in stroke patients. Specifically, DAE is utilized for denoising EMG signals, extracting features, and reducing noise to improve the signal's noise resistance. CNN is employed for spatial feature extraction, while LSTM captures temporal dependencies in gesture sequences. By integrating these three deep learning models, our aim is to enhance the accuracy and robustness of rehabilitation gesture recognition. We validate the proposed method's effectiveness on an EMG dataset from seven subjects through experiments and compare it with traditional machine learning and individual CNN and LSTM algorithms. Experimental results demonstrate significant performance improvements of our hybrid model in rehabilitation gesture recognition tasks, indicating promising application prospects and practical significance.

关键词： Support vector machines Deep learning Accuracy Noise Gesture recognition Stroke (medical condition) Feature extraction Electromyography Convolutional neural networks Long short term memory

Enhancing Ion Separation Efficiency: Janus Charged Nanofiltration Membrane Fabricated Via Polyethyleneimine-Manipulated Interfacial Polymerization

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SSRN 2024年

作者： Qi, Ting Chen, Xianfu Lu, Tiandan Xu, Rong Zhong, Jing Jiangsu Key Laboratory of Advanced Catalytic Materials & Technology School of Petrochemical Engineering Changzhou University Changzhou213164 China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Nanjing211816 China

This research introduces highly efficient nanofiltration (NF) membranes designed for the effective rejection of both divalent cations and anions, a critical feature for advanced water treatment technologies. We have devised a simple yet adaptable approach for fabricating Janus polyamide (PA) thin-films characterized by dual charges, which exhibit pronounced selectivity towards both mono-/divalent anions and cations. Leveraging a straightforward interfacial polymerization (IP) process, we integrated high molecular weight polyethyleneimine (PEI) within the PA matrix. This strategy ensured the preferential formation of a dense, negatively charged upper layer dominated by piperazine (PIP), while the substantial molecular size of PEI facilitated the emergence of a positively charged, more porous lower layer, thus giving rise to a distinctively charged and structurally heterogeneous PA thin-film. Furthermore, the strategic inclusion of PEI facilitated the formation of aqueous phase microphases, which serve as templates for the formation of PA thin films, thereby promoting the development of nano-wrinkled surface topologies. This structural innovation not only enhances water molecule throughput (16.0 L m‒2 h‒1 bar‒1) but also optimizes ion selectivity through a meticulous interplay of steric hindrance and Donnan effects. Consequently, the Janus charged NF membranes we developed exhibit exceptional selectivity for mono-/divalent ions, particularly demonstrating remarkable ion selectivity for Cl‒/SO42‒ and Li+/Mg2+ of 102 and 24, respectively. Our findings introduce a pioneering avenue for fabricating NF membranes that proficiently separate mono-/divalent ions, promising significant advancements in water treatment and purification endeavors. © 2024, The Authors. All rights reserved.

关键词： Molecules

Insight into the Mechanism of Gradient Fine Grains for Super Strength-Ductility Behavior

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SSRN 2023年

The gradient fine grains on low-carbon steel surface were produced via ultrasonic impact treatment, which led to super combination of high strength and ductility. The underlying mechanism was studied with tensile deformation testing and microstructure analysis. Results of the study showed that the grain size had a gradient increasing from 120nm at top surface to 5~8μm inside the bulk, determined by EBSD and TEM. In the gradient fine grain region, the angle of grain boundary is generally low, in the range of 2~15°. Compared with original microstructure, the surface gradient fine gains can achieve a higher work hardening rate, and has the lower ee-p values of 7.5%. A DIC technology was employed to analyze variations in strain during the tensile deformation. It is demonstrated that the surface gradient distribution of grain size can reduce the stress concentration, resulting in higher resistance to uneven deformation. Such a capability is attributed to the decreased dislocation density and Schimidt factor due to gradient fine gain distribution during tensile deformation. Compared with the original microstructure, a number of dislocation walls (or cells, or clusters) induced by tensile deformation can hinder the movement of dislocations. In addition, the surface gradient fine grains have faster recovery and proliferation of movable dislocation density, which can lead to higher work-hardening ability. As a result, the surface gradient fine grains can attain a combination of excellent strength and ductility. © 2023, The Authors. All rights reserved.

关键词： Strain hardening

Intrinsic Mechanisms of Morphological Engineering and Carbon Doping for Improved Photocatalysis of 2D/2D Carbon Nitride Van Der Waals Heterojunction

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Energy & Environmental Materials 2023年第3期6卷 96-106页

作者： Jinqiang Zhang Xiaoli Zhao Lin Chen Shuli Li Haijun Chen Yuezhao Zhu Shuaijun Wang Yang Liu Huayang Zhang Xiaoguang Duan Mingbo Wu Shaobin Wang Hongqi Sun School of Engineering Edith Cowan University270 Joondalup DriveJoondalupWA 6027Australia College of Chemical Engineering China University of Petroleum(East China) Qingdao 266580China Jiangsu Key Laboratory of Process Enhancement and New Energy Equipment Technology School of Mechanical and Power EngineeringNanjing Tech UniversityNanjing 211816China Center for Integrated Nanostructure Physics Institute for Basic Science(IBS)Sungkyunkwan UniversitySuwon 16419Republic of Korea School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaide SA 5005Australia State Key Laboratory of Heavy Oil ProcessingInstitute of New EnergyCollege of Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Van der Waals(VDW)heterojunctions in a 2D/2D contact provide the highest area for the separation and transfer of charge *** this work,a top-down strategy with a gas erosion process was employed to fabricate a 2D/2D carbon nitride VDW heterojunction in carbon nitride(g-C_(3)N_(4))with carbon-rich carbon *** created 2D semiconducting channel in the VDW structure exhibits enhanced electric field exposure and radiation absorption,which facilitates the separation of the charge carriers and their ***,compared with bulk g-C_(3)N_(4)and its nanosheets,the photocatalytic performance of the fabricated carbon nitride VDW heterojunction in the water splitting reaction to hydrogen is improved by 8.6 and 3.3 times,respectively,while maintaining satisfactory ***,the finite element method(FEM)was employed to evaluate and clarify the contributions of the formation of VDW heterojunction to enhanced photocatalysis,in agreement quantitatively with experimental *** study provides a new and effective strategy for the modification and more insights to performance improvement on polymeric semiconductors in photocatalysis and energy conversion.

关键词： carbon nitride Van der Waals heterojunctions enhanced electric field exposure improved radiation absorption photocatalytic water splitting promoted dynamics of charge carriers