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High Voltage 2024年第2期9卷 267-274页

作者： Xianhao Fan shu Niu Hanhua Luo Jizhong liang Fang liu Wenqiang li Weidong liu Wensheng Gao Yulong Huang Chuanyang li Jinliang He School of Electrical Engineering Tsinghua UniversityBeijingChina Electric Power Research Institute Shangxi Power Grid CorporationTaiyuanShanxiChina Shandong Taikai Electrical Insulation Co. Ltd.TaianShandongChina

The micro-defects in epoxy-based insulation materials generate a local high electric field which results in continuous degradation,seriously endangering the insulation system of gas-insulated switchgears.A highly sensitive detection technique is reported for micro-defects of insulation pull rods based on the photon counting(PC)*** re-sults demonstrated that for an epoxy-based insulation pull rod,the photons released during electroluminescence and ionisation at 2 kV,which is less than the partial discharge inception voltage,can be clearly *** findings presented a strong correlation between photon counts and defect *** has been conducted to elucidate the mechanism behind defect-induced PC,employing the amplification of ionising luminescence through electric field distortion induced by micro defects and the augmentation of electroluminescence through the aggregation of trap *** this regard,the authors verified that PC can serve as a potential tool in the detection of micro-insulation defects,which also has huge potential in online insulation condition monitoring.

关键词： technique. insulation defect

Detection and analysis of landslide geomorphology based on UAV vertical photogrammetry

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Journal of Mountain Science 2024年第4期21卷 1190-1214页

作者： BI Rui GAN shu YUAN Xiping li Kun li Raobo LUO Weidong CHEN Cheng GAO Sha HU lin ZHU Zhifu School of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China Plication Engineering Research Center of Spatial Information Surveying and Mapping Technology in Plateau and Mountainous Areas Set by Universities in Yunnan Province Kunming 650093China West Yunnan University of Applied Sciences Key Laboratory of Mountain Real Scene Point Cloud Data Processing and Application for Universities in Yunnan ProvinceDali 671006China

High-resolution landslide images are required for detailed geomorphological analysis in complex topographic environment with steep and vertical landslide *** study proposed a vertical route planning method for unmanned aerial vehicles(UAVs),which could achieve rapid image collection based on strictly calculated route *** effectiveness of this method was verified using a DJI Mavic 2 Pro,obtaining high-resolution landslide images within the Dongchuan debris flow gully,in the Xiaojiang River Basin,Dongchuan District,Yunnan,China.A three-dimensional(3D)model was constructed by the structure-from-motion and multi-view stereo(SfM-MVS).Micro-geomorphic features were analyzed through visual interpretation,geographic information system(GIS),spatial analysis,and mathematical statistics *** results demonstrated that the proposed method could obtain comprehensive vertical information on landslides while improving measurement *** 3D model was constructed using the vertically oriented flight route to achieve centimeter-level accuracy(horizontal accuracy better than 6 cm,elevation accuracy better than 3 cm,and relative accuracy better than 3.5 cm).The UAV technology could further help understand the micro internal spatial and structural characteristics of landslides,facilitating intuitive acquisition of surface *** slope of landslide clusters ranged from 36°to 72°,with the majority of the slope facing east and *** elevation levels were relatively consistent while middle to lower elevation levels gradually decreased from left to right with significant variations in lower elevation *** the rainy season,surface runoff was abundant,and steep topography exacerbated changes in surface *** route method is suitable for unmanned aerial vehicle(UAV)landslide surveys in complex mountainous *** geomorphological analysis methods used will provide references for identifying and describing topographic

关键词： UAV Landslide Vertical route SfM-MVS Topographic features

Major depressive disorder:hypothesis,mechanism,prevention and treatment

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Signal Transduction and Targeted Therapy 2024年第3期9卷 913-944页

作者： Lulu Cui shu li Siman Wang Xiafang Wu Yingyu liu Weiyang Yu Yijun Wang Yong Tang Maosheng Xia Baoman li Department of Forensic Analytical Toxicology School of Forensic MedicineChina Medical UniversityShenyangChina liaoning Province Key Laboratory of Forensic Bioevidence Sciences ShenyangChina China Medical University Centre of Forensic Investigation ShenyangChina International Joint Research Centre on Purinergic Signalling/Key Laboratory of Acupuncture for Senile Disease(Chengdu University of TCM) Ministry of Education/School of Health and RehabilitationChengdu University of Traditional Chinese Medicine/Acupuncture and Chronobiology Key Laboratory of Sichuan ProvinceChengduChina Department of Orthopaedics The First HospitalChina Medical UniversityShenyangChina

Worldwide,the incidence of major depressive disorder(MDD)is increasing annually,resulting in greater economic and social ***,the pathological mechanisms of MDD and the mechanisms underlying the effects of pharmacological treatments for MDD are complex and unclear,and additional diagnostic and therapeutic strategies for MDD still are *** currently widely accepted theories of MDD pathogenesis include the neurotransmitter and receptor hypothesis,hypothalamicpituitary-adrenal(HPA)axis hypothesis,cytokine hypothesis,neuroplasticity hypothesis and systemic influence hypothesis,but these hypothesis cannot completely explain the pathological mechanism of *** it is still hard to adopt only one hypothesis to completely reveal the pathogenesis of MDD,thus in recent years,great progress has been made in elucidating the roles of multiple organ interactions in the pathogenesis MDD and identifying novel therapeutic approaches and multitarget modulatory strategies,further revealing the disease features of ***,some newly discovered potential pharmacological targets and newly studied antidepressants have attracted widespread attention,some reagents have even been approved for clinical treatment and some novel therapeutic methods such as phototherapy and acupuncture have been discovered to have effective improvement for the depressive *** this work,we comprehensively summarize the latest research on the pathogenesis and diagnosis of MDD,preventive approaches and therapeutic medicines,as well as the related clinical trials.

关键词： prevention acupuncture hypothesis

Hydrodynamic Characteristics of Undular tidal Bores in the Qiantang River Based on Field Observations

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China Ocean Engineering 2024年第3期38卷 505-518页

作者： ZHANG shu-yu PAN Cun-hong ZHANG Shen-yang li Ruo-hua CHENG Wenlong XIE Dong-feng Zhejiang Tongji Vocational College of Science and Technology Hangzhou 311231China Zhejiang Institute of Hydraulics and Estuary Hangzhou 310020China

Understanding the undular tidal bores in the Qiantang River is essential for effective river management and *** breaking tidal bores have been studied extensively, reports on undular tidal bores in the Qiantang Riverremain limited. Furthermore, observed data on undular tidal bores fulfilling the requirements of short measurementtime intervals, and spring, medium, and neap tide coverage, and providing detailed data for the global vertical stratificationof flow velocity are quite limited. Based on field observations at Qige in the Qiantang estuary, we analyzedthe characteristics of undular tidal bores. The results showed that the flooding amplitude (a) of the first wave isalways larger than its ebbing amplitude (b). Moreover, the vertical distribution of the maximum flood velocity exhibitesthree shapes, influenced by the tidal range, while that of the maximum ebb velocity exhibites a single shape. Duringthe initial phase of the flood tide in the spring and medium tides, the upper water body experiences multiple oscillatingchanges along the flow direction, corresponding to the alternating process of the crest and trough of the tide levelupon the arrival of the tidal bore. The tidal range is a crucial parameter in tidal bore hydrodynamics. By establishingthe relationship between hydrodynamic parameters and tidal range, other hydrodynamic parameters, such as the tidalbore height, maximum flood depth–averaged velocity, maximum flood stratified velocity at the measurement points,and duration of the flood tide current, can be effectively predicted, thereby providing an important reference for rivermanagement and maintenance.

关键词： tidal bores Qiantang Estuary tidal bore height tidal bore velocity propagation speed

Laser-rewritable room temperature phosphorescence based on in-situ polymerized tartaric acid

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Science China Chemistry 2024年第9期67卷 3029-3038页

作者： Tuo-Yu Zhou Tai-Wen li Hai-Fu Zhang Rui-lin Chai Qian Zhao Penglin Zhang Guang-Yue li Qian-Wen Wang Chang li Yu shu Zhi Fan Sheng-Hua li College of Chemical Engineering and Materials Science College of SciencesTianjin University of Science&TechnologyTianjin 300457China College of Chemical Engineering North China University of Science and TechnologyTangshan 063210China tianjin Key Laboratory of Multiplexed Identification for Port Hazardous Chemicals Tianjin University of Science&TechnologyTianjin 300457China

Organic room temperature phosphorescence(RTP)materials have potential applications in information technology and ***,the precise control of the afterglow in reversible manners remains challenging for organic ***,we report a kind of organic RTP material fabricated by simple heating mixtures of tartaric acid(TA)and aromatic acids,which can switch their phosphorescence by *** mixtures show tunable phosphorescence from indigo to orange with phosphorescence efficiency of up to 53.99% due to locking different organic luminogens by the TA-formed matrix through the noncovalent *** afterglow of those materials lasts a few seconds and disappears by water fumigation,which can be repeated in response to wet/heat *** drop-casting those materials on glass slides,a laser-repatternable phosphorescence is achieved by facile laser direct writing and quenched by water *** results open the opportunity for the design of smart stimuli-responsive phosphorescence materials from sustainable natural products.

关键词： room temperature phosphorescence tunable afterglows tartaric acid laser direct writing stimuli-response

Precipitation evolution and properties of Cu-15Ni-8Sn alloys via Al microalloying during ageing

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Rare Metals 2024年第10期43卷 5216-5228页

作者： Wei Luo li-Jun Peng Xu-Jun Mi Hao-Feng Xie Yi-Cheng Cao shu-Hui Huang State Key Laboratory of Nonferrous Metals and Processes GRINM Group Co.Ltd. GRIMAT Engineering Institute Co. Ltd. General Research Institute for Nonferrous Metals School of Materials Science and Engineering South China University of Technology

Studies have shown that microalloying Cu-Ni-Sn alloys using Al inhibits discontinuous precipitation reactions;however,the mechanism has not been investigated ***,this study explored the properties and precipitation evolution of Cu-15Ni-8Sn alloys without and with 1 wt%Al（Cu-15Ni-8Sn-1Al） during ageing at 500℃ through X-ray diffraction （XRD）,scanning electron microscopy and high-angle annular dark-field scanning transmission electron *** results revealed that in Cu-15Ni-8Sn alloy,DO22ordering first occurred after spinodal decomposition,subsequently transitioning to an L12ordering phase,during which the discontinuous precipitates gradually nucleated at the grain boundaries and formed *** alloy hardness increased sharply with ordering and then decreased rapidly after reaching its peak value,due to the dominance of the discontinuous precipitation ***,the DO22ordered phase did not appear during the ageing of Cu-15Ni-8Sn-1Al alloy,and a Ni3(Alx,Sn1-x) intermetallic compound with L12structure was formed,consuming Ni and Sn atoms,thereby significantly suppressing the discontinuous precipitation reaction and improving the stability during prolonged *** tensile strength （yield strength） of Cu-15Ni-8Sn and Cu-15Ni-8Sn-1Al alloys at peak hardness were 855 （755） and 936 MPa （892 MPa）,respectively,and their main strengthening mechanisms were solid solution strengthening and precipitation *** addition of 1 wt% Al effectively improved the precipitation strengthening effect of Cu-Ni-Sn alloys but severely decreased the ductility.

关键词： Al addition Cu-15Ni-8Sn Precipitation sequence Strengthening mechanism

Copper oxide-modified highly reversible Zn powder anode for aqueous Zn metal batteries

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Rare Metals 2024年第10期43卷 5005-5016页

作者： Guan-Qun liu Biao Fu Zhe-Xuan liu Lan-Yan li shu-Quan liang Guo-Zhao Fang School of Materials Science and Engineering Key Laboratory of Electronic Packaging and Advanced Functional Materials of Hunan ProvinceCentral South University School of Science Hunan University of Technology and Business National Energy Metal Resources and New Materials Key Laboratory Central South University

With the advantages of mature preparation technology,structural adjustability and suitability for large-scale application,Zn powder anode is considered to be an ideal electrode for realizing low-cost,high-energy-density aqueous Zn metal ***,the high specific surface of Zn powders leads to severe side reactions such as hydrogen evolution and corrosion,thus limiting their widespread use Here,this work develops a novel CuO@Zn powder anode with a synergy effect of surface wrapping and *** powders are uniformly wrapped by small CuO particles due to the strong adsorption between Zn and *** wrapped CuO particles build a good conductive framework to inhibit the structural collapse of the Zn powder caused by corrosion and non-uniform ***,CuO can also be used as a seed to guide the uniform deposition of Zn ions through its strong binding energy with *** a result,the Cu O@Zn anode can maintain a long cyclic life of 900 h at current density of 1 mA·cm-2and capacity of 1 mAh·cm-2,as well as contribute to an excellent capacity retention of 92%after 800cycles for CuO@Zn||NH4V4O10full *** at high current density of 5 A·g-1,the full cell exhibits a specific capacity of more than 200 mAh·g-1after 800 cycles,with a good capacity retention of 89%.This work provides a new idea for developing high-performance Zn powder-based anodes.

关键词： Aqueous Zn metal batteries Copper oxide Surface wrapping Zn anode Zn powder

Inhibition of Defect-Induced Ice Nucleation, Propagation, and Adhesion by Bioinspired Self-Healing Anti-Icing Coatings

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Research 2024年第1期2023卷 237-246页

作者： shu tian Ruiqi li Xinmeng liu Jiancheng Wang Junyu Yu Sijia Xu Yunqing tian Jing Yang Lei Zhang Department of Biochemical Engineering Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering(MOE)School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China Binzhou Institute of Technology Weiqiao-UCAS Science and Technology ParkBinzhou CityShandong Province 256606China

Anti-icing coatings on outdoor infrastructures inevitably suffer from mechanical injuries in numerous icing scenarios such as hailstorms,sandstorms,impacts of foreign objects,and icing–deicing ***,the mechanisms of surface-defect-induced icing are *** the defects,water molecules exhibit stronger adsorption and the heat transfer rate increases,accelerating the condensation of water vapor as well as ice nucleation and ***,the ice–defect interlocking structure increases the ice adhesion ***,a self-healing(at−20℃)antifreeze-protein(AFP)-inspired anti-icing coating is *** coating is based on a design that mimics the ice-binding and non-ice-binding sites in *** enables the coating to markedly inhibit ice nucleation(nucleation temperaturetion(propagation rateting can also autonomously self-heal at−20℃,as a result of multiple dynamic bonds in its structure,to inhibit defect-induced icing *** healed coating sustains high anti-icing and deicing performance even under various extreme *** work reveals the in-depth mechanism of defect-induced ice formation as well as adhesion,and proposes a self-healing anti-icing coating for outdoor infrastructures.

关键词： coating defect clarified

Rapid Phase Ambiguity Elimination Methods for DOA Estimator via Hybrid Massive MIMO Receive Array

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Chinese Journal of Electronics 2024年第1期33卷 175-184页

作者： Xichao ZHAN Zhongwen SUN Feng shu Yiwen CHEN Xin CHENG Yuanyuan WU Qi ZHANG Yifan li Peng ZHANG School of Information and Communication Engineering Hainan University School of Electronic and Optical Engineering Nanjing University of Science and Technology

For a sub-connected hybrid multiple-input multiple-output(MIMO) receiver with K subarrays and N antennas, there exists a challenging problem of how to rapidly remove phase ambiguity in only single time-slot. A direction of arrival(DOA) estimator of maximizing received power(Max-RP) is proposed to find the maximum value of K-subarray output powers, where each subarray is in charge of one sector, and the center angle of the sector corresponding to the maximum output is the estimated true DOA. To make an enhancement on precision, Max-RP plus quadratic interpolation(Max-RP-QI) method is designed. In the proposed Max-RP-QI, a quadratic interpolation scheme is adopted to interpolate the three DOA values corresponding to the largest three receive powers of *** achieve the Cramer Rao lower bound, a Root-MUSIC plus Max-RP-QI scheme is developed. Simulation results show that the proposed three methods eliminate the phase ambiguity during one time-slot and also show low computational complexities. The proposed Root-MUSIC plus Max-RP-QI scheme can reach the Cramer Rao lower bound,and the proposed Max-RP and Max-RP-QI are still some performance losses 2–4 d B compared to the Cramer Rao lower bound.

关键词： Phased arrays Interpolation Wireless sensor networks Direction-of-arrival estimation Simulation Receiving antennas Massive MIMO

Implications for fault reactivation and seismicity induced by hydraulic fracturing

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Petroleum Science 2024年第2期21卷 1081-1098页

作者： Zi-Han Sun Ming-Guang Che li-Hong Zhu shu-Juan Zhang Ji-Yuan Lu Chang-Yu Jin Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines School of Resources and Civil Engineering and Key Laboratory of Liaoning Province on Deep Engineering and Intelligent TechnologyNortheastern UniversityShenyang110819LiaoningChina Research Institute of Petroleum Exploration&Development PetroChina Company LimitedBeijing100084China The Exploration and Development Research Institute of Daqing Oilfield limited Company Daqing163458HeilongjiangChina

Evaluating the physical mechanisms that link hydraulic fracturing(HF) operations to induced earthquakes and the anticipated form of the resulting events is significant in informing subsurface fluid injection operations. Current understanding supports the overriding role of the effective stress magnitude in triggering earthquakes, while the impact of change rate of effective stress has not been systematically addressed. In this work, a modified critical stiffness was brought up to investigate the likelihood, impact,and mitigation of induced seismicity during and after hydraulic fracturing by developing a poroelastic model based on rate-and-state fraction law and linear stability analysis. In the new criterion, the change rate of effective stress was considered a key variable to explore the evolution of this criterion and hence the likelihood of instability slip of fault. A coupled fluid flow-deformation model was used to represent the entire hydraulic fracturing process in COMSOL Multiphysics. The possibility of triggering an earthquake throughout the entire hydraulic fracturing process, from fracturing to cessation, was investigated considering different fault locations, orientations, and positions along the fault. The competition between the effects of the magnitude and change rate of effective stress was notable at each fracturing stage. The effective stress magnitude is a significant controlling factor during fracturing events, with the change rate dominating when fracturing is suddenly started or stopped. Instability dominates when the magnitude of the effective stress increases(constant injection at each fracturing stage) and the change rate of effective stress decreases(the injection process is suddenly stopped). Fracturing with a high injection rate, a fault adjacent to the hydraulic fracturing location and the position of the junction between the reservoir and fault are important to reduce the Coulomb failure stress(CFS) and enhance the critical stiffness as

关键词： Hydraulic fracturing Coulomb failure stress Rate-and-state fraction model linear stability analysis Critical stiffness Seismically induced fault