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Toroidal dipole response in rectangular waveguide:used to generate vector beams and vector vortex beams

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Chinese Optics Letters 2024年第1期22卷 90-97页

作者：罗灏陈聪高鹏冯越任紫燕乔昱嘉刘海 School of Information and Control Engineering China University of Mining and TechnologyXuzhou 221116China

Toroidal multipole is a special current distribution that has many different characteristics from electric multipole and magnetic multipole distributions.Because of its special properties,the toroidal dipole is a research hotspot in the field of metamaterials and nanophotonics.However,the low scattering of the toroidal dipole moment makes its excitation a challenging task.At present,there are relatively few studies on its specific engineering applications.In this paper,by slotting in the rectangular cavity,the excitation of an equivalent toroidal dipole is successfully achieved over a wide frequency range of 53-58 GHz.Results indicate that under the action of the toroidal dipole,the TE_(10)mode electromagnetic waves transmitted in the rectangular waveguide are converted into vector beams and are radiated outwards.Further adjusting the spatial distribution of the magnetic dipoles in the toroidal dipoles yields results that indicate that the resonance mode in the slot is still dominated by the magnetic toroidal dipole moment,and the electromagnetic waves radiating outward are vortex beams carrying vector polarization.The scattered energy of each dipole moment inside the antenna is calculated.This calculation verifies that the mass of the vector beam and vector vortex beam is closely related to the toroidal dipole supported by this antenna.The proposed structure can be applied to explorations in vortex filtering,in photon entanglement,and in the photonic spin Hall effect.

关键词： toroidal dipole vector beams vector vortex beams

Tailoring the austenite characteristics via dual nanoparticles to synergistically optimize the strength-ductility in cold rolled medium Mn steel

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Journal of Materials Science & Technology 2024年第2期169卷 158-171页

作者： Qizhe Ye Haokai Dong Qinyi Guo Yishuang Yu Lijie qiao Yu Yan Beijing Advanced Innovation Center for Materials Genome Engineering Corrosion and Protection CenterInstitute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510641China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

In this work,we proposed a novel Cu/θdual nanoparticles strategy to tailor the austenite characteris-tics of a medium Mn steel via a tempering-annealing process to optimize the mechanical properties.We explored the effects of Cu-rich particles and cementite precipitated in the tempering process on the austenite reversion during the subsequent annealing process.Both experiments and numerical simula-tions verified that the austenite inherited from cementite had a finer size and a higher Mn enrichment compared with the austenite originating from the tempered martensite matrix.In addition,quantitative evaluations revealed that the pinning effect exerted by the Cu-rich particles could significantly hinder theα/γinterface migration and the recrystallized grain growth,thereby further refining the final mi-crostructure.With contributions from the effects of dual nanoprecipitates on the austenite reversion,the heterogeneous austenite grains inherited from varying nucleation sites ensured the sustained and gradual deformation-induced martensite and twinning formation.Therefore,the Cu-added steels subjected to a tempering-annealing process achieved synergetic enhancement of the tensile strength from 1055 MPa to 1250 MPa and elongation from 33%to 45%.This strategy may provide new guidance for the development and alloy design of high-performance medium Mn steels.

关键词： Dual nanoparticles Medium Mn steel Tempering-annealing process Austenite reversion Mechanical properties

Safety and efficacy of omalizumab for antihistamine-resistant chronic urticaria in children:a case series and literature review

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World Journal of Pediatrics 2024年第3期20卷 294-298页

作者： Wei-Fang Zhu Chen Wang Jian-Jun qiao Lan-Juan Li Department of Dermatology First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China State Key Laboratory for Diagnosis and Treatment of Infectious Diseases National Clinical Research Center for Infectious DiseasesCollaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Chronic urticaria(CU)is a common skin disease characterized by the occurrence of wheals,with or without angioedema,lasting more than 6 weeks.The prevalence of CU is about 0.7%[1],but higher in children,with an incidence of 1.38%[1].The occurrence of severe pruritus and unpredictable wheals may severely impact patients'quality of life,cause psychological problems,including sleep disorders and depression,and lead to economic burden due to limitation on daily life and work[2,3].

关键词： edema prevalence children

Dynamic response of mountain tunnel,bridge,and embankment along the Sichuan-Tibet transportation corridor to active fault based on model tests

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Journal of Mountain Science 2024年第1期21卷 182-199页

作者： HUANG Beixiu qiao Sijia CHEN Xulei LI Lihui QI Shengwen Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Innovation Academy for Earth Science Chinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

The Sichuan-Tibet transportation corridor is prone to numerous active faults and frequent strong earthquakes.While extensive studies have individually explored the effect of active faults and strong earthquakes on different engineering structures,their combined effect remains unclear.This research employed multiple physical model tests to investigate the dynamic response of various engineering structures,including tunnels,bridges,and embankments,under the simultaneous influence of cumulative earthquakes and stick-slip misalignment of an active fault.The prototype selected for this study was the Kanding No.2 tunnel,which crosses the Yunongxi fault zone within the Sichuan-Tibet transportation corridor.The results demonstrated that the tunnel,bridge,and embankment exhibited amplification in response to the input seismic wave,with the amplification effect gradually decreasing as the input peak ground acceleration(PGA)increased.The PGAs of different engineering structures were weakened by the fault rupture zone.Nevertheless,the misalignment of the active fault may decrease the overall stiffness of the engineering structure,leading to more severe damage,with a small contribution from seismic vibration.Additionally,the seismic vibration effect might be enlarged with the height of the engineering structure,and the tunnel is supposed to have a smaller PGA and lower dynamic earth pressure compared to bridges and embankments in strong earthquake zones crossing active faults.The findings contribute valuable insights for evaluating the dynamic response of various engineering structures crossing an active fault and provide an experimental reference for secure engineering design in the challenging conditions of the Sichuan-Tibet transportation corridor.

关键词： Dynamic response Engineering structure Sichuan-Tibet transportation corridor Active fault Earthquake Model test

Chemical Composition, Pharmacological Effects and Clinical Applications of Cinobufacini

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Chinese Journal of Integrative Medicine 2024年第4期30卷 366-378页

作者： ZUO Qian XU Ding-qiao YUE Shi-jun FU Rui-jia TANG Yu-ping Key Laboratory of Shaanxi Administration of Traditional Chinese Medicine for TCM Compatibility Shaanxi University of Chinese MedicineXi'an(712046)China

Chinese medicine cinobufacini is an extract from the dried skin of Bufo bufo gargarizans Cantor,with active ingredients of bufadienolides and indole alkaloids.With further research and clinical applications,it is found that cinobufacini alone or in combination with other therapeutic methods can play an anti-tumor role by controlling proliferation of tumor cells,promoting apoptosis,inhibiting formation of tumor neovascularization,reversing multidrug resistance,and regulating immune response;it also has the functions of relieving cancer pain and regulating immune function.In this paper,the chemical composition,pharmacological effects,clinical applications,and adverse reactions of cinobufacini are summarized.However,the extraction of monomer components of cinobufacini,the relationship between different mechanisms,and the causes of adverse reactions need to be further studied.Also,high-quality clinical studies should be conducted.

关键词： cinobufacini chemical composition Chinese medicine pharmacological effect clinical application adverse effect

An approach for formation design and flight performance prediction based on aerodynamic formation unit:Energy-saving considerations

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Chinese Journal of Aeronautics 2024年第3期37卷 77-91页

作者： Nanxuan qiao Tielin MA Xiangsheng WANG Jie WANG jingcheng FU Pu XUE School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Institute of Unmanned System Beihang UniversityBeijing 100191China Key Laboratory of Advanced Technology of Intelligent Unmanned Flight System Ministry of Industry and Information TechnologyBeijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China Beijing Institute of Space Long March Vehicle Beijing 100076China

The performance improvement of swarm drones through aerodynamic shape optimization may be challenging due to folded size constraints imposed by the specific launch approach.However,fixed-wing aircraft swarms can benefit from formation flight in terms of energy consumption.This study introduces the concept of the"aerodynamic formation unit",which consists of two or three aircraft that form an inseparable unit of the formation.Considering the Unmanned Aerial Vehicle(UAV)distribution and wingtip vortex interference in the formation,two typical aerodynamic formation units are optimized by the variable-fidelity aerodynamic optimization method based on space mapping.The aerodynamic characteristics of the formation UAVs that affect flight performance,such as lift-to-drag ratio(L/D ratio)and static stability are analyzed by Computational Fluid Dynamics(CFD)simulations.The L/D ratio(cruising condition)of the following aircraft can be increased by 22.8%and 57.5%in the optimal units that involve two and three aircraft respectively.Moreover,this study conducts several CFD simulations for multi-aircraft formations formed by the units,which show that the average L/D ratio of the formation can be improved by more than 19%.These results verify the feasibility and effectiveness of the"aerodynamic formation unit"concept and the optimization framework for formation parameters.

关键词： Formation flight CFD Aerodynamic formation unit Wingtip vortices Foldable tandem-wing aircraft

Integrated Frequency-constrained Scheduling Considering Coordination of Frequency Regulation Capabilities from Multi-source Converters

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 261-274页

作者： Jiaming Li Ying qiao Zongxiang Lu Wei Ma Xin Cao Rongfu Sun the Department of Electrical Engineering Tsinghua UniversityBeijing 100084China the China Suntien Green Energy Limited Company Shijiazhuang 050011China the State Grid Jibei Electric Power Company Beijing 100054China

As the proportion of renewable energy(RE)increases,the inertia and the primary frequency regulation(FR)capability of the power system decrease.Thus,ensuring frequency security in the scheduling model has become a new technical requirement in power systems with a high share of RE.Due to a shortage of conventional synchronous generators,the frequency support of multi-source converters has become an indispensable part of the system frequency resources,especially variable-speed wind turbine generation(WTG)and battery energy storage(BES).Quantitative expression of the FR capability of multi-source converters is necessary to construct frequency-constrained scheduling model.However,the frequency support performance of these converter-interfaced devices is related to their working states,operation modes,and parameters,and the complex coupling of these factors has not been fully exploited in existing models.In this study,we propose an integrated frequency-constrained scheduling model considering the coordination of FR capabilities from multi-source converters.Switchable FR control strategies and variable FR parameters for WTG with or without reserved power are modeled,and multi-target allocation of BES capacity between tracking dispatch instruction and emergency FR is analyzed.Then,the variable FR capabilities of WTG and BES are embedded into the integrated frequency-constrained scheduling model.The nonlinear constraints for frequency security are precisely linearized through an improved iteration-based strategy.The effectiveness of the proposed model is verified in a modified IEEE 24-bus standard system.The results suggest that the coordinated participation of BES and WTG in FR can effectively reduce the cost of the scheduling model while meeting frequency security constraints.

关键词： Battery energy storage(BES) wind turbine generation(WTG) frequency regulation(FR) frequency security power system scheduling

Deep learning-based optical aberration estimation enables offline digital adaptive optics and super-resolution imaging

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Photonics Research 2024年第3期12卷 474-484页

作者： CHANG qiao HAOYU CHEN RUN WANG TAO JIANG YUWANG WANG DONG LI Department of Automation Tsinghua UniversityBeijing 100084China Institute for Brain and Cognitive Sciences Tsinghua UniversityBeijing 100084China National Laboratory of Biomacromolecules New Cornerstone Science LaboratoryCAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

Optical aberrations degrade the performance of fluorescence microscopy.Conventional adaptive optics(AO)leverages specific devices,such as the Shack–Hartmann wavefront sensor and deformable mirror,to measure and correct optical aberrations.However,conventional AO requires either additional hardware or a more complicated imaging procedure,resulting in higher cost or a lower acquisition speed.In this study,we proposed a novel space-frequency encoding network(SFE-Net)that can directly estimate the aberrated point spread functions(PSFs)from biological images,enabling fast optical aberration estimation with high accuracy without engaging extra optics and image acquisition.We showed that with the estimated PSFs,the optical aberration can be computationally removed by the deconvolution algorithm.Furthermore,to fully exploit the benefits of SFE-Net,we incorporated the estimated PSF with neural network architecture design to devise an aberration-aware deeplearning super-resolution model,dubbed SFT-DFCAN.We demonstrated that the combination of SFE-Net and SFT-DFCAN enables instant digital AO and optical aberration-aware super-resolution reconstruction for live-cell imaging.

关键词： optics resolution enable

Nitrogen‑Doped Magnetic‑Dielectric‑Carbon Aerogel for High‑Efficiency Electromagnetic Wave Absorption

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Nano-Micro Letters 2024年第1期16卷 313-327页

作者： Shijie Wang Xue Zhang Shuyan Hao jing qiao Zhou Wang Lili Wu Jiurong Liu Fenglong Wang Key Laboratory for Liquid‑Solid Structural Evolution and Processing of Materials Ministry of Education Shandong UniversityJinan 250061People’s Republic of China School of Mechanical Engineering Shandong UniversityJinan 250061People’s Republic of China Shenzhen Research Institute of Shandong University Shenzhen 518057GuangdongPeople’s Republic of China

Carbonbased aerogels derived from biomass chitosan are encountering a flourishing moment in electromagnetic protection on account of lightweight,controllable fabrication and versatility.Nevertheless,developing a facile construction method of component design with carbon-based aerogels for high-efficiency electromagnetic wave absorption(EWA)materials with a broad effective absorption bandwidth(EAB)and strong absorption yet hits some snags.Herein,the nitrogen-doped magnetic-dielectric-carbon aerogel was obtained via ice template method followed by carbonization treatment,homogeneous and abundant nickel(Ni)and manganese oxide(MnO)particles in situ grew on the carbon aerogels.Thanks to the optimization of impedance matching of dielectric/magnetic components to carbon aerogels,the nitrogen-doped magnetic-dielectric-carbon aerogel(Ni/MnO-CA)suggests a praiseworthy EWA performance,with an ultra-wide EAB of 7.36 GHz and a minimum reflection loss(RLmin)of−64.09 dB,while achieving a specific reflection loss of−253.32 dB mm−1.Furthermore,the aerogel reveals excellent radar stealth,infrared stealth,and thermal management capabilities.Hence,the high-performance,easy fabricated and multifunctional nickel/manganese oxide/carbon aerogels have broad application aspects for electromagnetic protection,electronic devices and aerospace.

关键词： Electromagnetic wave absorption Wide bandwidth Dielectric-magnetic synergy Multifunction