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Acta mathematicae Applicatae Sinica 2025年第1期41卷 200-233页

作者： Ke guo Wan-biao ma School of mathematics and Physics University of Science and Technology BeijingBeijing 100083China

Kawasaki disease(KD)is an acute,febrile,systemic vasculitis that mainly affects children under five years of *** this paper,we propose and study a class of 5-dimensional ordinary differential equation model describing the vascular endothelial cell injury in the lesion area of *** model exhibits forward/backward *** is shown that the vascular injury-free equilibrium is locally asymptotically stable if the basic reproduction number R_(0)manent if the basic reproduction number R_(0)>1,and some explicit analytic expressions of ultimate lower bounds of the solutions of the model are *** results suggest that the control of vascular injury in the lesion area of KD is not only correlated with the basic reproduction number R_(0),but also with the growth rate of normal vascular endothelial cells promoted by the vascular endothelial growth factor.

关键词： Kawasaki disease model backward bifurcation Hopf bifurcation global stability permanence

Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

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Applied mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： Fan YANG Zhaoyang ma Xingming guo Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University Shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric studies. A new way that can regulate the bandgap is revealed by studying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

关键词： flexural wave bandgap graded design local resonance metamaterial O421+.5

A Wind Tunnel Experimental Study on the Wake Characteristics of a Horizontal Axis Wind Turbine

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Journal of Thermal Science 2025年第1期34卷 145-158页

作者： guo Xingduo LI Yinran LI Rennian ma Yulong WEI Kui College of Energy and Power Engineering Lanzhou University of TechnologyLanzhou 730050China Key Laboratory of Fluid machinery and Systems Lanzhou 730050China Gansu Provincial Technology Centre for Wind Turbines Lanzhou 730050China

The characteristics of wind turbine wakes are influenced by multiple factors,including the atmospheric boundary layer(ABL)wind and wind turbine operating conditions(e.g.,tip speed ratio and yaw angle).In this study,two types of ABL winds with different velocity gradients and turbulence intensities are generated in a wind tunnel through configurations of spires,baffles,and various numbers of roughness elements.A wind turbine with a rotor diameter of 0.8 m and a hub height of 0.6 m is tested under varying tip speed ratios,yaw angles,and ABL wind *** results indicate that the streamwise velocity deficit in the near-wake region becomes more pronounced with an increase in the tip speed ratio,while the far-wake velocity deficit remains largely unaffected by changes in the tip speed *** the yaw angle increases,the wake deflection becomes more prominent and the wake narrows;the offset of the wake center at various downstream positions grows linearly,reaching a maximum value of approximately half the rotor ***,the turbulence level and influence range in the wake region are reduced when the turbine is *** ABL wind conditions,high turbulence intensity in the incoming flow accelerates wake recovery,and the Reynolds stress at different lateral positions tends to become consistent with increasing longitudinal ***,turbulence has a significant impact on the meandering characteristics of the wind turbine wake,with greater fluctuations in the wake center observed under higher turbulence ***,this study provides insights that could inform the optimal operation of wind farms.

关键词： horizontal axis wind turbine wind tunnel experiment wind turbine wake turbulence

Effects of the extrusion parameters on microstructure,texture and room temperature mechanical properties of extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy

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International Journal of Minerals,Metallurgy and materials 2025年第1期32卷 136-146页

作者： Chenjin Zhang Guangyu Yang Lei Xiao Zhiyong Kan Jing guo qiang Li Wanqi Jie State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China College of materials Science and Engineering Fuzhou UniversityFuzhou 350108China College of Chemistry and Environmental Science Qujing Normal UniversityQujing 655011China

Microstructure,texture,and mechanical properties of the extruded Mg-2.49Nd-1.82Gd-0.2Zn-0.2Zr alloy were investigated at different extrusion temperatures(260 and 320℃),extrusion ratios(10:1,15:1,and 30:1),and extrusion speeds(3 and 6 mm/s).The experimental results exhibited that the grain sizes after extrusion were much finer than that of the homogenized alloy,and the second phase showed streamline distribution along the extrusion direction(ED).With extrusion temperature increased from 260 to 320℃,the microstructure,texture,and mechanical properties of alloys changed *** dynamic recrystallization(DRX)degree and grain sizes enhanced as the extrusion ratio increased from 10:1 to 30:1,and the strength gradually decreased but elongation(EL)*** the extrusion speed increased from 3 to 6 mm/s,the grain sizes and DRX degree increased significantly,and the samples presented the typical-rare-earth(RE)*** alloy extruded at 260℃ with extrusion ratio of 10:1 and extrusion speed of 3 mm/s showed the tensile yield strength(TYS)of 213 MPa and EL of 30.6%.After quantitatively analyzing the contribution of strengthening mechanisms,it was found that the grain boundary strengthening and dislocation strengthening played major roles among strengthening *** results provide some guidelines for enlarging the industrial application of extruded Mg-RE alloy.

关键词： Mg-rare earth alloys extrusion temperature extrusion ratio extrusion speed strengthening mechanisms

Characterization of petrophysical and seismic properties for CO2 storage with sensitivity analysis

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Petroleum Science 2025年第1期22卷 193-209页

作者： Yan-Jiao Dong Yi Shen Kai guo Xiao-Qin Wu qiang mao Wen-Yue Sun Zhi-qiang Wang State Key Laboratory of Offshore Oil and Gas Exploitation Geosciences Department China University of Petroleum (East China) CNOOC Research Institute Ltd. School of Petroleum Engineering China University of Petroleum (East China)

Saline aquifers are considered as highly favored reservoirs for CO2sequestration due to their favorable properties. Understanding the impact of saline aquifer properties on the migration and distribution of CO2plume is crucial. This study focuses on four key parameters—permeability, porosity, formation pressure, and temperature—to characterize the reservoir and analyse the petrophysical and elastic response of CO2. First, we performed reservoir simulations to simulate CO2saturation, using multiple sets of these four parameters to examine their significance on CO2saturation and the plume migration ***, the effect of these parameters on the elastic properties is tested using rock physics *** established a relationship of compressional wave velocity（Vp） and quality factor（Qp） with the four key parameters, and conducted a sensitivity analysis to test their sensitivity to Vpand Qp. Finally, we utilized visco-acoustic wave equation simulated time-lapse seismic data based on the computed Vpand Qpmodels, and analysed the impact of CO2saturation changes on seismic data. As for the above numerical simulations and analysis, we conducted sensitivity analysis using both homogeneous and heterogeneous models. Consistent results are found between homogeneous and heterogeneous models. The permeability is the most sensitive parameter to the CO2saturation, while porosity emerges as the primary factor affecting both Qpand Vp. Both Qpand Vpincrease with the porosity, which contradicts the observations in gas reservoirs. The seismic simulations highlight significant variations in the seismic response to different parameters. We provided analysis for these observations, which serves as a valuable reference for comprehensive CO2integrity analysis, time-lapse monitoring, injection planning and site selection.

关键词： CO2 storage Time-lapse seismic CO2 plume Sensitivity analysis Rock physics Reservoir simulation Saline aquifer

Enhanced battery life prediction with reduced data demand via semi-supervised representation learning

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Journal of Energy Chemistry 2025年第2期101卷 524-534页

作者： Liang ma Jinpeng Tian Tieling Zhang Qinghua guo Chi Yung Chung School of Mechanical Materials Mechatronic and Biomedical Engineering University of Wollongong Department of Electrical and Electronic Engineering and Research Centre for Grid Modernisation The Hong Kong Polytechnic University Photonics Research Institute The Hong Kong Polytechnic University School of Electrical Computer and Telecommunications Engineering University of Wollongong

Accurate prediction of the remaining useful life(RUL) is crucial for the design and management of lithium-ion *** various machine learning models offer promising predictions,one critical but often overlooked challenge is their demand for considerable run-to-failure data for *** of such training data leads to prohibitive testing efforts as the run-to-failure tests can last for ***,we propose a semi-supervised representation learning method to enhance prediction accuracy by learning from data without RUL *** approach builds on a sophisticated deep neural network that comprises an encoder and three decoder heads to extract time-dependent representation features from short-term battery operating data regardless of the existence of RUL *** approach is validated using three datasets collected from 34 batteries operating under various conditions,encompassing over 19,900 charge and discharge *** method achieves a root mean squared error(RMSE)within 25 cycles,even when only 1/50 of the training dataset is labelled,representing a reduction of 48%compared to the conventional *** also demonstrate the method's robustness with varying numbers of labelled data and different weights assigned to the three decoder *** projection of extracted features in low space reveals that our method effectively learns degradation features from unlabelled *** approach highlights the promise of utilising semi-supervised learning to reduce the data demand for reliability monitoring of energy devices.

关键词： Lithium-ion batteries Battery degradation Remaining useful life Semi-supervised learning

Yielding performance of compact yielding anchor cable in working state:Analytical theory and experimental evaluation of yielding resistance enhancement effect

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International Journal of Mining Science and Technology 2025年第1期35卷 101-120页

作者： Zhenyu Wang Bo Wang Xinxin guo Jinjin Li Zhenwang ma State Key Laboratory of Intelligent Geotechnics and Tunnelling Southwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Geohazard Prevention and Geoenvironmental Protection Chengdu University of TechnologyChengdu 610059China China Design Group Co. Ltd.Nanjing 210001China

To elucidate the yielding performance of compact yielding anchor cables in working state,a yielding mechanical model incorporating extrusion friction and fastening rotation under confining pressure is *** yielding resistance enhancement effect(ω)caused by working environment constraints is evaluated through multi-layer composite sleeve hole expansion analysis,forming a theoretical framework for calculating the working yielding *** and in-situ pull-out tests are conducted to determine the yielding performance and validate the analytical *** main conclusions are:(1)Yielding force and energy-release capacity increase withω,significantly outperforming the unconfined state.(2)In-situ tests under varying rockmass and geostress conditions(F1–F3)determine the yielding force increases to 183.4–290.1,204.0–290.8,and 235.0–327.1 kN.(3)The slight deviation(–12.5%to 6.2%)between the theoretical and measured yielding force confirms that the analytical theory effectively describes the working yielding performance.(4)ωincreases with higher geostress and improved rock mechanical properties,with initial geostress(σ_(0))and elastic modulus of surrounding rock(E_(3))identified as critical parameters.

关键词： Compact yielding anchor cables Working state Yielding resistance enhancement effect Yielding mechanical performance Pull-out test

magnetron sputtered nickel oxide with suppressed interfacial defect states for efficient inverted perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 348-355页

作者： guoqiang ma Qin Tan Zhaoning Li Jingwei Xiu Jiafeng Wang Tianle Cheng Dong He qiang Sun Xuhang ma Francesco Lamberti Zhubing He Department of materials Science and Engineering Institute of Innovative Materials(I2M)Shenzhen Key Laboratory of Full Spectral Solar Electricity Generation(FSSEG)Southern University of Science and Technology(SUSTech)Shenzhen 518055GuangdongChina Core Research Facilities Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Chemical Sciences Department of Industrial EngineeringUniversity of PadovaVia Gradenigo 6a35131 PadovaItaly

Widely used spin-coated nickle oxide (NiOx) based perovskite solar cells often suffer from severe interfacial reactions between the NiOxand adjacent perovskite layers due to surface defect states,which inherently impair device performance in a long-term view,even with surface molecule *** this study,we developed high-quality magnetron-sputtered NiOxthin films through detailed process optimization,and compared systematically sputtered and spin-coated NiOxthin film surfaces from materials to *** sputtered NiOxfilms exhibit improved crystallinity,smoother surfaces,and significantly reduced Ni3+or Ni vacancies compared to their spin-coated ***,the interface between the perovskite and sputtered NiOxfilm shows a substantially reduced density of defect *** solar cells (PSCs) fabricated with our optimally sputtered NiOxfilms achieved a high power conversion efficiency (PCE) of up to 19.93%and demonstrated enhanced stability,maintaining 86.2% efficiency during 500 h of maximum power point tracking under one standard sun ***,with the surface modification using (4-(2,7-dibromo-9,9-dimethylacridin-10(9H)-yl)butyl)p hosphonic acid (DmacPA),the device PCE was further promoted to 23.07%,which is the highest value reported for sputtered NiOxbased PSCs so far.

关键词： Nickle oxide magnetron sputter Defect Stability Perovskite solar cell

Wnt2bb signaling promotes pharyngeal chondrogenic precursor proliferation and chondrocyte maturation by activating Yap expression in zebrafish

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Journal of Genetics and Genomics 2025年第2期52卷 220-230页

作者： Xiaojuan guo Liping Yang Yujie Wang Mengna Yuan Wenqing Zhang Xinyu He qiang Wang State Key Laboratory of Membrane Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China Division of Cell Developmental and Integrative BiologySchool of MedicineSouth China University of TechnologyGuangzhouGuangdong 510006China Innovation Centre of Ministry of Education for Development and Diseases The Sixth Affiliated HospitalSchool of MedicineSouth China University of TechnologyGuangzhouGuangdong 510006China

Pharyngeal cartilage morphogenesis is crucial for the formation of craniofacial *** neural crest cells are specified at the neural plate border,migrate to pharyngeal arches,and differentiate into pharyngeal chondrocytes,which subsequently flatten,elongate,and stack like coins during *** the developmental processes prior to chondrocyte maturation have been extensively studied,their subsequent changes in morphology and organization remain largely ***,we show that wnt2bb is expressed in the pharyngeal ectoderm adjacent to the chondrogenic precursor cells in *** of Wnt2bb leads to a reduction in nuclearβ-catenin,which impairs chondrogenic precursor proliferation and disrupts chondrocyte morphogenesis and organization,eventually causing a severe shrinkage of pharyngeal ***,the decrease ofβ-catenin in wnt2bb^(-/-)mutants is accompanied by the reduction of Yap *** of Yap can restore the proliferation of chondrocyte progenitors as well as the proper size,shape,and stacking of pharyngeal *** findings suggest that Wnt/β-catenin signaling promotes Yap expression to regulate pharyngeal cartilage formation in zebrafish.

关键词： Wnt/β-catenin signaling YAP Wnt2bb Chondrocyte maturation Pharyngeal cartilage Zebrafish

Fast and robust production of quantum superposition states by the fractional shortcut to adiabaticity

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Communications in Theoretical Physics 2025年第1期77卷 54-64页

作者： Guan-qiang Li Hao guo Yu-Qi Zhang Bo Yang Ping Peng Department of Physics and Institute of Theoretical Physics Shaanxi University of Science and TechnologyXi'an 710021China

The fractional shortcut to adiabaticity(f-STA)for the production of quantum superposition states is proposed firstly via a three-level system with aΛ-type linkage pattern and a four-level system with a tripod *** fast and robust production of the coherent superposition states is studied by comparing the populations for the f-STA and the fractional stimulated Raman adiabatic passage(f-STIRAP).The states with equal proportions can be produced by fixing the controllable parameters of the driving pulses at the final moment of the whole *** effects of the pulse intensity and the time delay of the pulses on the production process are discussed by monitoring the populations on all of the quantum *** particular,the spontaneous emission arising from the intermediate state is investigated by the quantum master *** result reveals that the f-STA exhibits superior advantages over the f-STIRAP in producing the superposition states.

关键词： quantum population transfer shortcut to adiabaticity coherent superposition states dark states spontaneous emission