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Acta Mathematicae Applicatae Sinica 2024年

作者： Shi-lin MI Guang-zhi DU Yao RONG Li-yun ZUO school of Mathematics and Statistics Shandong Normal University College of engineering Physics Shenzhen Technology University school of Mathematical Sciences University of Jinan

This paper mainly presents and studies some local and parallel finite element methods for the unsteady magnetohydrodynamic equations with low electromagnetic Reynolds number. Firstly, both the semi discrete and fully discrete local algorithms are provided and investigated, and the theoretical tool crucial to the analysis of the fully discrete local algorithm is obtained. Subsequently, we generalize the fully discrete local algorithm to the fully discrete parallel algorithm. At the end, some numerical experiments are provided to validate the effectiveness and efficiency of our algorithms.

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Effect of austenitizing condition on mechanical properties,microstructure and precipitation behavior of AISI H13 steel

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Journal of Iron and Steel Research International 2024年第1期31卷 143-156页

作者： An-gang Ning Yang Liu Rui Gao Stephen Yue Ming-bo Wang Han-jie Guo College of Materials Science and engineering Taiyuan University of TechnologyTaiyuan030024ShanxiChina Department of Mining and Materials engineering McGill UniversityMontrealQCH3A 0C5Canada ASSAB Tooling Technology(Chongqing)Co. Ltd.Chongqing401120China school of Metallurgical and Ecological engineering University of Science and Technology BeijingBeijing100083China

The effects of austenitizing temperature(1223,1303,and 1373 K)and holding time(1-1500 s)on the microstructure,mechanical properties,and precipitation behavior of the H13 hot work die steel were *** results indicate a softening phenomenon when H13 steel is austenitized at 1303 K beyond 900 s and 1373 K beyond 600 s,*** the sample held for 1200 s,the tensile strength is found capable of reaching up to 2.2 GPa when quenched from a temperature above 1303 ***,prior-austenite grain size increases with the increase in austenitizing *** kinetic behavior of the precipitates(mainly MC-type carbides)in H13 steel could be elaborated through the principles set forth by the Arrhenius and Avrami ***,the comprehensive strengthening of the H13 steel was discussed in *** results show that the activation energy of the transformed fraction of carbides is higher than that of the diffusion process for common alloying elements(Cr,V,Mo,and Ni)found in the *** suggests that it would be difficult for precipitates to dissolve into the matrix when H13 steel is austenitized at high *** the increasing austenitizing temperature,the precipitation fraction decreases,and the dislocation density *** dislocation strengthening is regarded as the dominant strengthening contributed to yield strength in as-quenched H13 steel.

关键词： H13 steel Austenitizing Mechanical property Precipitation behavior Comprehensive strengthening

Inhibition of Heterogeneous Nucleation in Water by Hydrogel Coating

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Research 2024年第2期2023卷 139-147页

作者： Siyang Li Panpan Zhu Yaoting Xue Lei Wangg Tuck-Whye Wong Xuxu Yang Haoei Zhou Tiefeng Li We Yang Department of engineering Mechanics Zhejiang UniversityHangzhou 310027China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang UniversityHangzhou 310027China Center for X-Mechanics Department of Engineering MechanicsZhejiang UniversityHangzhou 310027China school of Biomedical engineering and Health Sciences and Advanced Membrane Technology Research Centre Universiti Teknologi MalaysiaSkudai 81310Malaysia

Heterogeneous nucleation plays a critical role in the phase transition of water,which can cause damage in various ***,we report that heterogeneous nucleation can be inhibited by utilizing hydrogel coatings to isolate solid surfaces and ***,which contain over 90%water when fully swelled,exhibit a high degree of similarity to *** to this similarity,there is a great energy barrier for heterogeneous nucleation along the water-hydrogel ***,hydrogel coatings,which possess polymer networks,exhibit higher fracture energy and more robust adhesion to solid surfaces compared to *** high fracture and adhesion energy acts as a deterrent for fracture nucleation within the hydrogel or along the hydrogel-solid *** a hydrogel layer approximately 100μm thick,the boiling temperature of water under atmospheric pressure can be raised from 100 to 108℃.Notably,hydrogel coatings also result in remarkable reductions in cavitation pressure on multiple solid *** have demonstrated the efficacy of hydrogel coatings in preventing damages resulting from acceleration-induced *** coatings have the potential to alter the energy landscape of heterogeneous nucleation on the water-solid interface,making them an exciting avenue for innovation in heat transfer and fluidic systems.

关键词： fracture cavitation similarity

Investigation of Maxima Assumptions in Modelling Tropical Cyclone- Induced Hazards in the South China Sea

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China Ocean engineering 2024年第3期38卷 491-504页

作者： WEN Ze-guo WANG Fu-ming WAN Jing YANG Fan school of Civil engineering Sun Yat-sen University&Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Guangdong Academy of Safety Science and Technology Guangzhou 510060China Guangdong Key Laboratory of Oceanic Civil engineering Guangzhou 510275China Advanced Energy Science and Technology Guangdong Laboratory(Yangjiang Offshore Wind Energy Laboratory) Yangjiang 529500China

The present study aims to examine the suitability of two commonly used assumptions that simplify modelling metoceanconditions for designing offshore wind turbines in the South China Sea (SCS). The first assumption assumes thatjoint N-year extreme wind and wave events can be independently estimated and subsequently combined. The secondone assumes peak wind and waves can be modelled as occurring simultaneously during a tropical cyclone (TC) *** better understand the potential TC activity, a set of 10000 years synthetic TC events are generated. The wind fieldmodel and the Mike 21 spectral wave model are employed to model the TC-induced hazards. Subsequently, theeffect of the assumptions is evaluated by analyzing the peak structural response of both monopile and semisubmersibleoffshore wind turbines during TC events. The results demonstrate that the examined assumptions are generally *** assessing the implications of these assumptions, valuable insights are obtained, which can inform andimprove the modelling of TC-induced hazards in the SCS region.

关键词： tropical cyclone numerical wave modelling hazards offshore wind turbines structural response

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Seismic effectiveness evaluation and optimized design of tie up method for securing museum collections

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Earthquake engineering and engineering Vibration 2024年第3期23卷 741-763页

作者： Wang Meng Yan Yi Yang Weiguo Liu Pei Ge Jiaqi Ma Botao school of Civil engineering Beijing Jiaotong UniversityBeijing 100044China Beijing’s Key Laboratory of Structural Wind engineering and Urban Wind Environment Beijing 100044China Beijing General Municipal engineering Design&Research Institute Co. LtdBeijing 100082China China Aviation Planning and Design Institute(Group)Co.Ltd. Beijing 100120China

To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used for typical museum collection replicas have been carried *** influence of body shape and fixed measure parameters on the seismic responses of replicas and the interaction behavior between replicas and fixed measures have been *** on the results,seismic effectiveness evaluation indexes of the tie up method are *** suggestions for fixed strategies are given,which provide a basis for the exhibition of delicate museum collections considering the principle of minimizing seismic responses and *** analysis results show that a larger ratio of height of mass center to bottom diameter led to more intense rocking *** the initial pretension of fishing lines was conducive to reducing the seismic responses and stress variation of the *** comprehensive consideration of the interaction forces and effective securement,it is recommended to apply 20%of breaking stress as the initial *** specific museum collections that cannot be effectively protected by the independent tie up method,an optimized strategy of a combination of fishing lines and fasteners is recommended.

关键词： tie up method museum collections shaking table test seismic effectiveness optimized design

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Research on the variation of dielectric properties of oil-paper insulation for power equipment over a wide temperature range

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High Voltage 2024年第3期9卷 648-658页

作者： Mingze Zhang Muhe Yu Wen Zhou Yilin Liang Shengjie Lei Yunbo Shi Limin Qu Key Laboratory of engineering Dielectrics and Its Application Ministry of Education Harbin University of Science and TechnologyHarbinChina school of Measurement and Communication engineering Harbin University of Science and TechnologyHarbinChina Electric Power Research Institute State Grid Heilongjiang Electric Power Company LimitedHarbinChina

The main part of oil-immersed power equipment is oil-paper *** lower ambient temperatures,transformer oil will become *** a result,compared to those at room temperature or operating temperature,the frequency domain dielectric properties of oil-paper insulation at low temperatures are drastically *** evaluating the insulation condition of electrical equipment,it is essential to accurately determine their dielectric *** paper described the FDS test,the DC conductivity test,and the transformer oil viscosity test,which was carried out in a laboratory environment for different ageing of oil-immersed pressboard and transformer oil at 233–373 *** ef-fects of temperature on the dielectric properties at the competing mechanisms of polarisation and conductivity loss were clarified based on variations of the FDS *** the viscosity change of ageing transformer oil at low temperatures,the Arrhenius and VFT viscosity equations were used to achieve a fitting calculation in the different temperature *** on the molecular/ion transition model in the force field and electric field,the characterisation relationships between the dynamic viscosity,DC conductivity,and test temperature of transformer oil were *** limita-tions of conventional transformer oil equivalent dielectric relaxation models over a wide temperature range were finally clarified by combining the test findings of the DC con-ductivity over a wide temperature range with observed and simulated *** paper provides an essential theoretical reference when using the FDS test to diagnose the insulation performance of oil-immersed power equipment in extremely cold regions.

关键词： insulation viscosity immersed

Fuzzy-Inverse-Model-Based Networked Tracking Control Frameworks of Time-Varying Signals

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1708-1710页

作者： Shiwen Tong Dianwei Qian Keya Yuan Dexin Liu Yuan Li Jiancheng Zhang the College of Robotics Beijing Union UniversityBeijing 100101China the school of Control and Computer engineering North China Electric Power UniversityBeijing 102206China

Dear Editor,Tracking control in networked environment is a very challenging problem due to the contradiction of rapid response to the time-varying signal and the inevitable delay introduced by networks. This letter has proposed several fuzzy-inverse-model-based network tracking control frameworks which are helpful in handling the system with nonlinear dynamics and uncertainties.

关键词： contradiction letter inverse

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Surface-targeted functionalization of nickel-rich cathodes through synergistic slurry additive approach with multi-level impact using minimal quantity

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Nano Research 2024年第1期17卷 333-343页

作者： Jing Zhang Jiapei Li Longhao Cao Wenhua Cheng Ziyin Guo Xiuxia Zuo Chao Wang Ya-Jun Cheng Yonggao Xia Yudai Huang State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830017China Ningbo Institute of Materials Technology&engineering Chinese Academy of SciencesNingbo 315201China school of Materials Science and engineering Tongji UniversityShanghai 200240China Center of Materials Science and Optoelectronics engineering University of Chinese Academy of SciencesBeijing 100049China

LiNi0.8Co0.1Mn0.1O_(2)(NCM811),a Ni-rich layered oxide,is a promising cathode material for high-energy density lithium-ion batteries(LIBs).However,its structural instability,caused by adverse phase transitions and continuous oxygen release,as well as deteriorated interfacial stability due to excessive electrolyte oxidative decomposition,limits its widespread *** address these issues,a new concept is proposed that surface targeted precise functionalization(STPF)of the NCM811 cathode using a synergistic slurry additive(SSA)*** approach involves coating the NCM811 particle surface with 3-aminopropyl dimethoxy methyl silane(3-ADMS),followed by the precise deposition of ascorbic acid via an acid-base *** slurry additives induce the formation of an ultra-thin spinel surface layer and a stable cathode–electrolyte interface(CEI),which enhances the electrochemical kinetics and inhibits crack *** STPF strategy implemented by the SSA approach significantly improves the cyclic stability and rate performance of the NCM811 cathode in both half-cell and full-cell *** work establishes a promising strategy to enhance the structural stability and electrochemical performance of nickel-rich cathodes and provides a feasible route to promote practical applications of high-energy density lithium-ion battery technology.

关键词： nickel-rich cathode slurry additive lithium-ion battery cathode–electrolyte interface ascorbic acid phase transition

Accelerated reconstruction of ZIF-67 with significantly enhanced glucose detection sensitivity

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Nano Research 2024年第6期17卷 4737-4743页

作者： Huihui Jin Weihao Zeng Wei Qian Lun Li Pengxia Ji Zhengying Li Daping He school of Information engineering Wuhan University of TechnologyWuhan 430070China Hubei engineering Research Center of RF-Microwave Technology and Application Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Research on metal-organic framework(MOF)-based non-enzymatic glucose sensors usually ignores the impact of the surface reconstruction degree of MOF on the activity of catalyzing glucose *** this work,we choose zeolitic imidazolate framework-67(ZIF-67),which is commonly used in glucose sensing,as a representative to investigate the influence of reconstruction degree on its structure and glucose catalytic *** employing the electrochemical activation strategy,the activity of ZIF-67 in catalyzing glucose gradually increased with the prolongation of the activation time,reaching the optimum after 2 h *** detection sensitivity of the activated ZIF-67 was 19 times higher than that of the initial ZIF-67,and the limit of detection(LOD)was lowered from 7 to 0.4μ*** findings demonstrate that the oxidation degree of ZIF-67 deepened rapidly with continuously activation and was basically reconstructed to CoOOH after 2 h activation,accompanied by a morphological change from cuboctahedral to ***,theoretical investigation revealed that ZIF-67 is not suitable as a stable glucose sensor electrode since the adsorbed glucose molecules hasten the dissociation of ligands and the breaking of Co-N bond in ***,our work has important implications for the rational design of next-generation MOF-based glucose sensors.

关键词： zeolitic imidazolate framework-67(ZIF-67) glucose oxidation electrochemical activation reconstruction CoOOH

Glaucoma surgery experiments using digital microscope-integrated optical coherence tomography and OCT-compatible instruments

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Journal of Innovative Optical Health Sciences 2024年第5期17卷 105-113页

作者： Tianliang Jiang Jinyu Fan Ning Tang Yi He Guohua Shi school of Biomedical engineering(Suzhou)Division of Life Sciences and Medicine University of Science and Technology of China Hefei 230026 P.R.China Jiangsu Key Laboratory of Medical Optics Suzhou Institute of Biomedical engineering and Technology Chinese Academy of Science Suzhou 215163P.R.China

There is a certain failure rate in traditional glaucoma surgery because of the lack of depth information in microscope *** this work,we present a digital microscope-integrated optical coherence tomography(MIOCT)system and several custom-made OCT-compatible instruments for glaucoma *** ophthalmologists were asked to perform trabeculectomy and canaloplasty on live porcine eyes using the system and *** surgery,a subjective feedback survey about the user experience was *** experiment results showed that our system can help surgeons easily locate important tissue structures during *** custom-made instruments also solved the shadowing problem in OCT *** preferred to use the system in their future practice.

关键词： Microscope-integrated optical coherence tomography OCT-compatible instruments glaucoma surgery trabeculectomy canaloplasty