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Journal of Energy Chemistry 2024年第10期97卷 520-528页

作者： Xiaolin hu Zhenkun Wu Chaohe Xu School of Science Chongqing Key Laboratory of New Energy Storage Materials and Devices Chongqing University of Technology School of Chemistry and Engineering Chongqing University College of Materials Science and Engineering Chongqing University

The development of redox bifunctional electrocatalysts with high performance,low cost,and long lifetimes is essential for achieving clean energy *** study proposed an atom capture strategy for anchoring dual single atoms（DSAs） in a zinc-zeolitic imidazolate framework（Zn-ZIF）,followed by calcination under an N2atmosphere to synthesize ruthenium-platinum DSAs supported on a nitrogendoped carbon substrate（RuPt DSAs-NC）.Theoretical calculations showed that the degree of Ru 5dxz-*O 2pxorbital hybridization was high when*O was adsorbed at the Ru site,indicating enhanced covalent hybridization of metal sites and oxygen ligands,which benefited the adsorption of intermediate *** presence of the RuPtN6active center optimized the absorption-desorption behavior of intermediates,improving the electrocatalytic performance of the oxygen reduction reaction（ORR） and the oxygen evolution reaction（DER）,RuPt DSAs-NC exhibited a 0.87 V high half-wave potential and a 268 mV low overpotential at 10 mA cm-2in an alkaline ***,rechargeable zinc-air batteries（ZABs）achieved a peak power density of 171 MW *** RuPt DSAs-NC demonstrated long-term cycling for up to 500 h with superior round-trip *** study provided an effective structural design strategy to construct DSAs active sites for enhanced electrocata lytic performance.

关键词： Atom capture Dual single atoms catalysts Oxygen evolution reaction Oxygen reduction reaction Rechargeable Zn-air batteries

Dynamic characteristics and application of dual throat fluidic thrust vectoring nozzle

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CHINESE JOURNAL OF AERONAUTICS 2024年第9期37卷 85-99页

作者： Xu, Buxian hu, Dongping Feng, Lihao Beihang Univ Fluid Mech Key Lab Minist Educ Beijing 100191 Peoples R China Dongfang Turbine Co Ltd State Key Lab Clean & Efficient Turbomachinery Pow Dongfang Elect Corp Deyang 618000 Peoples R China

Thrust vectoring technology plays an important role in improving the maneuverability of aircraft. In order to overcome the disadvantages of mechanical thrust vectoring nozzles, such as complications of structure and significant increases in weight and cost, fluidic thrust vectoring nozzles are proposed. Dual Throat fluidic thrust vectoring Nozzle (DTN) has received wide attention due to its excellent thrust vectoring efficiency and minimal thrust loss. In this study, three-dimensional unsteady numerical simulations of a single axisymmetric DTN are conducted first to analyze its dynamic response. Then the pitch and yaw control characteristics of DTN equipped on a flying-wing aircraft are investigated. It is found that the dynamic response will experience three stages: rapid-deflecting stage, oscillating stage, and steady stage. A complete recirculation zone forms at the end of the rapid-deflecting stage, which pushes the primary flow to attach to the wall opposite the secondary injection. Meanwhile, the exhaust flow is deflected. In terms of DTN's application, the DTN equipped on the flying-wing aircraft is capable of providing effective pitch and yaw moments at all angles of attack and Mach numbers. In addition, continuous pitch and yaw moments can be obtained by adjusting the secondary mass flow ratios. The control moment is generated due to the asymmetrical pressure distribution of nozzle surface, which is mainly contributed by the pressure decrease on the secondary injection surface. Moreover, the DTN equipped on the flying-wing aircraft has a relatively high thrust vectoring efficiency of around 5 degrees/% and a thrust coefficient of around 0.95 when nozzle pressure ratio equals 4. These results provide an important theoretical basis for the practical application of DTN. (c) 2024 Production and hosting by Elsevier Ltd. on behalf of Chinese Society of Aeronautics and Astronautics. This is an open access article under the CC BY-NC-ND license (http://creativecommo

关键词： Dual throat nozzle Dynamic response characteristic Flow control Flying-wing aircraft

Advanced Sensors Towards Ubiquitous Power Internet of Things

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 871-890页

作者： Jinliang He Zhifei Han Jun hu Department of Electrical Engineering Tsinghua UniversityBeijing 100084China IEEE CSEE

The ubiquitous power Internet of Things(UPIoT)uses modern information technology and advanced communication technologies to realize interconnection and human-computer interaction in all aspects of the power *** has the characteristics of comprehensive state perception and efficient information processing,and has broad application prospects for transformation of the energy *** fundamental facility of the UPIoT is the sensor-based information *** using advanced sensors,Wireless Sensor Networks(WSNs),and advanced data processing technologies,Internet of Things can be realized in the power *** this paper,a framework of WSNs based on advanced sensors towards UPIoT is *** addition,the most advanced sensors for UPIoT purposes are reviewed,along with an explanation of how the sensor data obtained in UPIoT is utilized in various scenarios.

关键词： Advanced sensors ubiquitous power Internet of Things wireless sensor networks

Analysis of Sea Surface Temperature Cooling in Typhoon Events Passing the Kuroshio Current

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Journal of Ocean University of China 2024年第2期23卷 287-303页

作者： hu Yuyi SHAO Weizeng SHEN Wei ZUO Juncheng JIANG Tao hu Song College of Marine Sciences Shanghai Ocean UniversityShanghai 201306China East China Sea Environment Monitoring Ministry of Natural ResourcesShanghai 201206China China Waterborne Transport Research Institute Ministry of TransportBeijing 100088China

The aim of this study is to investigate the sea surface temperature(SST) cooling as typhoons pass the Kuroshio Current.A numerical circulation model,denoted as the Stony Brook Parallel Ocean Model(sbPOM),was used to simulate the SST,which includes four wave-induced effect terms(i.e.,radiation stress,nonbreaking waves,Stokes drift,and breaking waves) simulated using the third-generation wave model,called WAVEWATCH-Ⅲ(WW3).The significant wave height(SWH) measurements from the Jason-2 altimeter were used to validate the WW3-simulated results,yielding a root mean square error(RMSE) of less than 0.50 m and a correlation coefficient(COR) of approximately *** water temperature measured from the Advanced Research and Global Observation Satellite was applied to validate the model ***,the RMSE of the SST is 0.92℃ with a COR of approximately *** revealed in the sbPOM-simulated SST fields,a reduction in the SST at the Kuroshio Current region was observed as a typhoon passed,although the water temperature of the Kuroshio Current is relatively *** variation of the SST is consistent with that of the current,whereas the maximum SST lagged behind the occurrence of the peak ***,the Stokes drift plays an important role in the SST cooling after analyzing four wave-induced terms in the background of the Kuroshio *** sensitivity experiment also showed that the accuracy of the water temperature was significantly reduced when including breaking waves,which play a negative role in the inside part of the *** variation in the mean mixing layer depth(MLD) showed that a typhoon could enhance the mean MLD in the Kuroshio Current area in September and October,whereas a typhoon has little influence on the mean MLD in the Kuroshio Current area in ***,the mean MLD rapidly decreased with the weakening of the strong wind force and wave-induced effects when a typhoon crossed the Kuroshio Current.

关键词： typhoon wave sea surface temperature Kuroshio Current

Defect engineering on constructing surface active sites in catalysts for environment and energy applications

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 11-32页

作者： Yawen Cai Baowei hu Xiangke Wang School of Life Science Shaoxing UniversityShaoxing 312000China College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China

The precise engineering of surface active sites is deemed as an efficient protocol for regulating surfaces and catalytic properties of *** engineering is the most feasible option to modulate the surface active sites of *** specific active sites on the catalyst allows precise modulation of its electronic structure and physicochemical ***,we outlined the engineering of several types of defects,including vacancy defects,void defects,dopant-related defects,and defect-based single atomic *** overview of progress in fabricating structural defects on catalysts via de novo synthesis or post-synthetic modification was ***,the applications of the well-designed defective catalysts in energy conversion and environmental remediation were carefully ***,current challenges in the precise construction of active defect sites on the catalyst and future perspectives for the development directions of precisely controlled synthesis of defective catalysts were also proposed.

关键词： defect engineering vacancy void defects doping single atomic sites

Impact of Polymer Matrix on Polymer Mechanochromism from Excited State Intramolecular Proton Transfer

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Chinese Journal of Chemistry 2024年第6期42卷 611-616页

作者： Yu Wu Xin Cheng huan hu Shui hu Zhimin Ma Zhiyong Ma Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing State Key Laboratory of Organic-Inorganic CompositesCollege of Chemical EngineeringBeijing University of Chemical TechnologyBeijing100029 China Center of Advanced Elastomer Materials College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing100029 China College of Engineering Peking UniversityBeijing100871 China

Mechanochromic polymers based on non-covalent changes have attracted much attention ***,we report the impact of inter/intramolecular hydrogen bonds on polymer mechanochromism from the excited state intramolecular proton transfer (ESIPT) ***-NH2-OH and PhMz=2A are designed and obtained by simple and high-yield synthesis,and are connected into polyurethane and poly(methyl acrylate-co-2-ethylhexyl acrylate),*** the initial state,the PhMz-NH2-OH@PU sample shows blue fluorescence from the excited enol form (E*) excitons,owing to intermolecular hydrogen bonds that interrupt the ESIPT reactions but the PhMz=2A@PMA-2-EA sample expresses cyan fluorescence belonging to the excited keto form (K*) emission,implying that the intramolecular hydrogen bonds ***,under stretching,external force can tune the emission of the PhMz=2A@PMA-2-EA sample from K* to E* *** external force can putatively still promote a bond rotation,ESIPT reactions remain equivalently interrupted in both the relaxed and stressed states in a hydrogen-bond donating *** calculation confirms the force-induced increase in dihedral angle for the transition of ESIPT-on/***,PhMz-NH2-OH@PU and PhMz=2A@PMA-2-EA showed disparate initial ESIPT states and further different responses/sensitivity to *** study reports a novel and efficient strategy for enriching mechanochromic investigation and extending the applications of ESIPT reactions.

关键词： Polymer mechanochromism Excited state intramolecular proton transfer Hydrogen bonding Supramolecular chemistry Elastomers

Allosteric DNAzyme-based encoder for molecular information transfer

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Chinese Chemical Letters 2024年第7期35卷 235-241页

作者： Minghao hu Tianci Xie Yuqiang hu Longjie Li Ting Wang Tongbo Wu School of Pharmacy Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Oncology Tongji Hospital of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China GI Cancer Research Institute Tongji HospitalHuazhong University of Science and TechnologyWuhan 430030China School of Life Science and Technology Wuhan Polytechnic UniversityWuhan 430023China State Key Laboratory of Bioelectronics National Demonstration Center for Experimental Biomedical Engineering EducationSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China

Dynamic DNA nanotechnology plays a significant role in nanomedicine and information science due to its high programmability based on Watson-Crick base pairing and nanoscale *** DNA machines and networks have been widely used in various fields,including molecular imaging,biosensors,drug delivery,information processing,and logic *** serve as crucial components for information compilation and transfer,allowing the conversion of information from diverse application scenarios into a format recognized and applied by DNA ***,there are only a few encoder designs with DNA ***,the molecular priority encoder is hardly *** this study,we introduce allosteric DNAzyme-based encoders for information *** design of the allosteric domain and the recognition arm allows the input and output to be independent of each other and freely *** pre-packaged mode design achieves uniformity of baseline dynamics and dynamics *** also integrated non-nucleic acid molecules into the encoder through the aptamer design of the allosteric ***,we developed the 2^(n)-n encoder and the EndoⅣ-assisted priority encoder inspired by immunoglobulin's molecular structure and effector *** our knowledge,the proposed encoder is the first enzyme-free DNA encoder with DNA output,and the priority encoder is the first molecular priority encoder in the DNA reaction *** encoders avoid complex operations on a single molecule,and their simple structure facilitates their application in complex DNA circuits and biological scenarios.

关键词： DNAzyme Encoder Nucleic acids DNA circuit DNA strand displacement Dynamic DNA nanotechnology

Disorders of cardiac rhythm in China

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Journal of Geriatric Cardiology 2024年第7期21卷 703-712页

作者： Sheng-Shou hu The Writing Committee of the Report on Cardiovascular Health and Diseases in China

The Annual Report on Cardiovascular Health and Diseases in China(2022)intricate landscape of cardiovascular health in *** connection with the previous section,this seventh section of the report offers a comprehensive analysis of dis-orders of heart rhythm in *** 2021,China has achieved significant development and gratifying results in many aspects of the field of *** bundle branch pacing(LBBP),as an emerging pacing technique originating from China,has received widespread *** research results have emerged on its indications,surgical procedures,clinical evaluation,and com-parison with other pacing *** feasibility,effectiveness,and safety have been basically verified,but its long-term pro-gnosis still needs further confirmation from larger samples and longer follow-up time research *** pacemakers have begun to be used in a wider range of clinical applications,and related large sample cohort studies have been *** addi-tion,there are also noteworthy new achievements in the fields of pacemaker remote programming,anticoagulation and radiofre-quency catheter ablation(RFCA)therapy for atrial fibrillation,and implantable cardioverter defibrillator prevention of sudden cardiac *** terms of clinical practice,due to COVID-19 pandemic,the number of RFCA procedures and other device im-plantations in China has fluctuated,but it has gradually recovered since 2020.

关键词： cardiac prevention landscape

Finite-time tracking control of heterogeneous multi-AUV systems with partial measurements and intermittent communication

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Science China(Information Sciences) 2024年第5期67卷 165-182页

作者： Bo CHEN Jiangping hu Bijoy Kumar GHOSH School of Automation Engineering University of Electronic Science and Technology of China Key Laboratory of Intelligent Analysis and Decision on Complex Systems Chongqing University of Posts and Telecommunications Yangtze Delta Region Institute (huzhou) University of Electronic Science and Technology of China Department of Mathematics and Statistics Texas Tech University

The development of a distributed trajectory-tracking control strategy that is independent of velocity measurements is critical to achieving finite-time tracking control of autonomous underwater vehicle(AUV) systems. In this study, a group of heterogeneous AUV systems with intermittent communication links is considered and a finite-time trajectory-tracking control strategy is developed. The strategy includes two observers and one controller proposed for each follower-AUV. The first observer, a hybrid finite-time observer,estimates the state of the leader, whereas the second observer, which relies only on the position measurement,is proposed to estimate the states of the follower-AUV itself. In addition, a distributed trajectory-tracking controller is designed using the states estimated by the intermittent communication network even without velocity measurements. A homogeneous technique is utilized to prove that all followers can track the leader in a finite time. Finally, the effectiveness of the developed finite-time tracking control strategy is illustrated by numerical simulations.

关键词： distributed observer finite-time tracking homogeneous technique intermittent communication multiple heterogeneous AUVs

Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： Bo Wang Zhong Jiang Pei-Da hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIS)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control