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Rare Metals 2024年第7期43卷 3329-3340页

作者： Zi-Yue Yu Liang-Liang Wei xing-ye guo Bao-Peng Zhang Qing He Hong-Bo guo School of Materials Science and Engineering Beihang UniversityBeijing100191China Key Laboratory of High-Temperature Structure Materials and Protective Coatings(Ministry of Industry and Information Technology) Beihang UniversityBeijing 100191China Surface Engineering Research Institute Chinese Academy of Agricultural Mechanization SciencesBeijing 100083China

Thermal barrier coatings(TBCs) applied in aeroengines tend to be attacked by molten calcia-magnesiaalumino-silicate(CMAS) at high operating ***-stabilized zirconia(YSZ) coatings with quasicolumnar microstructure were fabricated by plasma spray physical vapor deposition(PS-PVD) *** chemic al changes,micros tructural transform ation,mechanical properties and degradation mechanisms of the CM AS-interacted TBCs in the thermal cycling tests were *** YSZ grains were dissolved in the CMAS melts,and then the ZrO_(2) grains were reprecipitated with spherical shape,accompanying with phase transformation from tetragonal(t) to monoclinic(m).The thermal cycling tests reveal that the YSZ coating fails at the early stage due to the attack of *** fractures in intracolumns lead to partial spallation of the *** failure of the coating occurs at the interfaces between thermally grown oxides(TGO) layer and YSZ topcoat;especially,the hardness and Young's modulus of the YSZ coatings increase intensively,as the coatings were infiltrated by the CMAS for a long time.

关键词： CMAS Thermal barrier coatings Young's modulus Thermal cycling behavior PS-PVD

Magnetic field enhanced single particle tunneling in MoS2-superconductor vertical Josephson junction

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Chinese Physics B 2020年第5期29卷 22-25页

作者： Wen-Zheng Xu Lai-Xiang Qin xing-guo ye Fang Lin Da-Peng Yu Zhi-Min Liao State Key Laboratory for Mesoscopic Physics and Collaborative Innovation Center of Quantum Matter School of PhysicsPeking UniversityBeijing 100871China Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and TechnologyShenzhen 518055China Frontiers Science Center for Nano-optoelectronics Peking UniversityBeijing 100871China

As a prototypical transition-metal dichalcogenide semiconductor, MoS2 possesses strong spin–orbit coupling, which provides an ideal platform for the realization of interesting physical phenomena. Here, we report the magnetotransport properties in NbN–MoS2–NbN sandwich junctions at low temperatures. Above the critical temperature around ~11 K, the junction resistance shows weak temperature dependence, indicating a tunneling behavior. While below ~11 K, nearly zero junction resistance is observed, indicating the superconducting state in the MoS2 layer induced by the superconducting proximity effect. When a perpendicular magnetic field ~1 T is applied, such proximity effect is suppressed, accompanying with insulator-like temperature-dependence of the junction resistance. Intriguingly, when further increasing the magnetic field, the junction conductance is significantly enhanced, which is related to the enhanced single particle tunneling induced by the decrease of the superconducting energy gap with increasing magnetic fields. In addition, the possible Majorana zero mode on the surface of MoS2 can further lead to the enhancement of the junction conductance.

关键词： proximity effect transition metal dichalcogenides magnetotransport

Orbit-Transfer Torque Driven Field-Free Switching of Perpendicular Magnetization

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Chinese Physics Letters 2022年第3期39卷 89-93页

作者： xing-guo ye Peng-Fei Zhu Wen-Zheng Xu Nianze Shang Kaihui Liu Zhi-Min Liao State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

The reversal of perpendicular magnetization(PM)by electric control is crucial for high-density integration of low-power magnetic random-access *** the spin-transfer torque and spin-orbit torque technologies have been used to switch the magnetization of a free layer with perpendicular magnetic anisotropy,the former has limited endurance because of the high current density directly through the junction,while the latter requires an external magnetic field or unconventional configuration to break the *** we propose and realize the orbit-transfer torque(OTT),that is,exerting torque on the magnetization using the orbital magnetic moments,and thus demonstrate a new strategy for current-driven PM reversal without external magnetic *** perpendicular polarization of orbital magnetic moments is generated by a direct current in a few-layer WTe_(2)due to the existence of nonzero Berry curvature dipole,and the polarization direction can be switched by changing the current *** by this principle,we construct the WTe_(2)/Fe_(3)GeTe_(2)heterostructures to achieve the OTT driven field-free deterministic switching of PM.

关键词： polarization switched Switching

Insight Into the Separation-of-Variable Methods for the Closed-Form Solutions of Free Vibration of Rectangular Thin Plates

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 329-355页

作者： Yufeng xing ye Yuan Gen Li Institute of Solid Mechanics Beihang University(BUAA)Beijing100191China

The separation-of-variable(SOV)methods,such as the improved SOV method,the variational SOV method,and the extended SOV method,have been proposed by the present authors and coworkers to obtain the closed-form analytical solutions for free vibration and eigenbuckling of rectangular plates and circular cylindrical *** taking the free vibration of rectangular thin plates as an example,this work presents the theoretical framework of the SOV methods in an instructive way,and the bisection–based solution procedures for a group of nonlinear eigenvalue ***,the explicit equations of nodal lines of the SOV methods are presented,and the relations of nodal line patterns and frequency orders are *** is concluded that the highly accurate SOV methods have the same accuracy for all frequencies,the mode shapes about repeated frequencies can also be precisely captured,and the SOV methods do not have the problem of missing roots as well.

关键词： Separation-of-variable method Rayleigh quotient nodal line eigenvalue equation bisection method

Strain-dependent resistance and giant gauge factor in monolayer WSe_(2)

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Chinese Physics B 2021年第9期30卷 464-468页

作者： Mao-Sen Qin xing-guo ye Peng-Fei Zhu Wen-Zheng Xu Jing Liang Kaihui Liu Zhi-Min Liao State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

We report the strong dependence of resistance on uniaxial strain in monolayer WSe_(2)at various temperatures,where the gauge factor can reach as large as *** observation of strain-dependent resistance and giant gauge factor is attributed to the emergence of nonzero Berry curvature *** increasing strain,Berry curvature dipole can generate net orbital magnetization,which would introduce additional magnetic scattering,decreasing the mobility and thus *** work demonstrates the strain engineering of Berry curvature and thus the transport properties,making monolayer WSe_(2)potential for application in the highly sensitive strain sensors and high-performance flexible electronics.

关键词： strain engineering van der Waals materials symmetry breaking orbital magnetization Berry curvature

Strain Tunable Berry Curvature Dipole, Orbital Magnetization and Nonlinear Hall Effect in WSe_(2) Monolayer

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Chinese Physics Letters 2021年第1期38卷 99-104页

作者： Mao-Sen Qin Peng-Fei Zhu xing-guo ye Wen-Zheng Xu Zhen-Hao Song Jing Liang Kaihui Liu Zhi-Min Liao State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China

The electronic topology is generally related to the Berry curvature,which can induce the anomalous Hall effect in time-reversal symmetry breaking *** monolayer transition metal dichalcogenides possesses two nonequivalent K and K’ valleys,having Berry curvatures with opposite signs,and thus vanishing anomalous Hall effect in this *** we report the experimental realization of asymmetrical distribution of Berry curvature in a single valley in monolayer WSe_(2) via applying uniaxial strain to break C_(3v) *** a result,although the Berry curvature itself is still opposite in K and K’ valleys,the two valleys would contribute equally to nonzero Berry curvature *** applying electric field E,the emergent Berry curvature dipole D would lead to an out-of-plane orbital magnetization M ∝ D·E,which further induces an anomalous Hall effect with a linear response to E^(2),known as nonlinear Hall *** show the strain modulated transport properties of nonlinear Hall effect in monolayer WSe_(2) with moderate hole-doping by *** second-harmonic Hall signals show quadratic dependence on electric field,and the corresponding orbital magnetization per current density M/J can reach as large as *** contrast to the conventional Rashba-Edelstein effect with in-plane spin polarization,such current-induced orbital magnetization is along the out-of-plane direction,thus promising for high-efficient electrical switching of perpendicular magnetization.

关键词： Berry curvature magnetization

Association between intra-pancreatic fat deposition and diseases of the exocrine pancreas: A narrative review

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World Journal of Gastroenterology 2025年第2期31卷 27-41页

作者： Jing ye Jian-guo Wang Rong-Qiang Liu Qiao Shi Wei-xing Wang Department of General Surgery Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina Department of Pancreatic Surgery Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina

Intrapancreatic fat deposition(IPFD)has garnered increasing attention in recent *** prevalence of IPFD is relatively high and associated with factors such as obesity,age,and ***,the pathophysiological mechanisms underlying IPFD remain unclear,with several potential contributing factors,including oxida-tive stress,alterations in the gut microbiota,and hormonal *** was found to be highly correlated with the occurrence and prognosis of exocrine pan-creatic *** imaging techniques remain the primary diagnostic approach for IPFD,an expanding array of biomarkers and clinical scoring systems have been identified for screening ***,effective treatments for IPFD are not available;however,existing medications,such as glucagon-like peptide-1 receptor agonists,and new therapeutic approaches explored in animal models have shown considerable potential for managing this *** paper reviews the pathogenesis of IPFD,its association with exocrine pancreatic disea-ses,and recent advancements in its diagnosis and treatment,emphasizing the significant clinical relevance of IPFD.

关键词： Intrapancreatic fat deposition Pancreatic steatosis Nonalcoholic fatty pancreas disease Pancreatitis Pancreatic cancer

Distributed optimal consensus control for multiagent systems based on event-triggered and prioritized experience replay strategies

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Science China(Information Sciences) 2025年第1期68卷 306-321页

作者： Cuijuan ZHANG Lianghao JI Shasha YANG xing guo Huaqing LI Chongqing Key Laboratory of Image Cognition Chongqing University of Posts and Telecommunications Key Laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of Electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词： multiagent systems event-triggered mechanism prioritized experience replay dual-structured neural networks optimal consensus control

Metrological traceable calibration of organic carbon and elemental carbon based on laboratory-generated reference materials

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Journal of Environmental Sciences 2025年第3期149卷 524-534页

作者： Yue Liu Junjie Liu Ji Xiao Jing ye Lixu guo Caiqing Yan Center for Environmental Metrology National Institute of Metrology ChinaBeijing 100029China College of Chemistry and Chemical Engineering Taiyuan University of TechnologyTaiyuan 030024China Environment Research Institute Shandong UniversityQingdao 266237China

Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate *** measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source *** accurate separation of OC and EC is controversial due to the charring of ***,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further *** RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC *** develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz *** generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC *** RMs were analyzed using different *** homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol ***,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.

关键词： Carbonaceous aerosol Split point Reference material Laboratory-generated Traceability

Detection using mask adaptive transformers in unmanned aerial vehicle imagery

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Optoelectronics Letters 2025年第2期21卷 113-120页

作者： ye Huibiao FAN Weiming guo Yuping WANG Xuna ZHOU Dalin China Telecommunication Corporation Zhejiang Branch Hangzhou 310020China Innovation Center for Smart Medical Technologies&Devices Binjiang Institute of Zhejiang UniversityHangzhou 100059China School of Computing University of PortsmouthPortsmouthPO13HEUK

Drone photography is an essential building block of intelligent transportation,enabling wide-ranging monitoring,precise positioning,and rapid ***,the high computational cost of transformer-based methods in object detection tasks hinders real-time result transmission in drone target detection ***,we propose mask adaptive transformer (MAT) tailored for such ***,we introduce a structure that supports collaborative token sparsification in support windows,enhancing fault tolerance and reducing computational *** structure comprises two modules:a binary mask strategy and adaptive window self-attention (A-WSA).The binary mask strategy focuses on significant objects in various complex *** A-WSA mechanism is employed to self-attend for balance perfomance and computational cost to select objects and isolate all contextual *** experiments on the challenging CarPK and VisDrone datasets demonstrate the effectiveness and superiority of the proposed ***,it achieves a mean average precision (mAP@0.5) improvement of 1.25%over car detector based on you only look once version 5 (CD-YOLOv5) on the CarPK dataset and a 3.75%average precision(AP@0.5) improvement over cascaded zoom-in detector (CZ Det) on the VisDrone dataset.

关键词： token mask imagery