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Observation of Small-amplitude Electromagnetic Cyclotron Waves in the Solar Wind

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Research in Astronomy and Astrophysics 2023年第4期23卷 94-102页

作者： Hai-Feng yang Guo-Qing Zhao Heng-qiang Feng Gilbert Pi qiang Liu Liang Xiang Qiu-Huan Li Dan-yang ren Institute of Space Physics Luoyang Normal UniversityLuoyang 471934China Henan Key Laboratory of Electromagnetic Transformation and Detection Luoyang 471934China Faculty of Mathematics and Physics Charles UniversityPrague 12116Czech Republic

Our previous studies on low-frequency electromagnetic cyclotron waves(ECWs)with amplitudes larger than 0.1nT in the solar wind revealed that the left-handed(LH)polarized ECWs are the dominant waves,and these waves preferentially occur in plasma conditions of high proton speed(V_(p)),high proton temperature(T_(p)),low proton density(N_(p)).In the present study,using magnetic field and plasma data from the Wind mission between 2005 and2015,we perform a survey of small-amplitude ECWs with amplitudes smaller than 0.1 *** is revealed for the first time that the small-amplitude right-handed(RH)polarized ECWs tend to frequently occur in plasmas characterized by low V_(p),low T_(p),low N_(p),although the small-amplitude LH ECWs still preferentially occur in plasma conditions similar to the LH ECWs with amplitudes larger than 0.1 *** investigation shows that the occurrences of small-amplitude RH ECWs and long-lasting radial interplanetary magnetic field(lrIMF)share the similar preferential plasma conditions of low T_(p)and low N_(p).During lrIMF events,in particular,the occurrence rates of RH and LH ECWs are comparable,with the occurrence rate of small-amplitude RH ECWs slightly larger than that of small-amplitude LH *** generation mechanism of the small-amplitude ECWs is discussed.

关键词： (Sun:)solar wind-magnetic fields-waves

Anisotropic and nonlinear metasurface for multiple functions

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Science China(Information Sciences) 2021年第9期64卷 165-174页

作者： Zhangjie LUO Xueyao ren qiang WANG qiang CHENG Tiejun CUI State Key Laboratory of Millimeter Waves School of Information Science and EngineeringSoutheast University Pazhou Lab Air and Missile Defense College Air Force Engineering University

We present a novel anisotropic and nonlinear metasurface integrated with multiple functions of diffuse scattering, beam splitting, and normal reflection, which can be switched in real time by tuning the polarization state or power level of the incident microwave. The key lies in the two judiciously designed anisotropic nonlinear particles in subwavelength scales that possess opposite reflection phases under one polarization and the same nonlinear power-dependent reflection phases under the orthogonal polarization. These properties are demonstrated comprehensively via comparisons between their reflection responses, receiving abilities, and nonlinear circuitry behaviors. In addition, both the spatial arrangement and the electrically enabling strategy of the particles are underpinned to pursue the proposed functions, which are verified through numerical simulations and measurements. When the metasurface is illuminated by plane waves coming from the direction perpendicular to it, a significant beam splitting effect is achieved with strong x-polarized incidence,which is switched to a specular reflection when the incoming power decreases. Under y-polarization,a diffuse scattering phenomenon is obtained, which is not dependent on the incident intensity. The study is expected to offer new solutions to many electromagnetic scenarios involving energy transmissions and protections.

关键词： multi-function metasurface nonlinear anisotropic polarization

Microstructure refinement and work hardening in a machined surface layer induced by turning Inconel 718 super alloy

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 937-949页

作者： Xiao-ping ren Zhan-qiang Liu School of Mechanical Engineering Shandong University Key Laboratory of High Efficiency and Clean Mechanical Manufacture Ministry of EducationShandong University

The microstructural changes in the machined surface layer of Ni-based super alloys essentially determine the final performance of the structural components of aerospace engines in which these alloys are *** this work,multiscale metallurgical observations using scanning electron microscopy,electron-backscatter diffraction microscopy,and transmission electron microscopy were conducted to quantitatively characterize the microstructure of the machined ***,to elucidate the factors that affect the formation of the refinement microstructure,the distributions of the deformation parameters(strain,strain rate,and temperature) in the machined subsurface were analyzed.A dislocation–twin interaction dynamic recrystallization mechanism for grain refinement during machining of Inconel 718 is ***,microhardness evolution induced by grain refinement in the machined surface is *** results suggest that the gradient microstructure and the work hardening can be optimized by controlling the cutting parameters during turning of Inconel 718.

关键词： grain refinement dislocation–twin interaction work hardening turning Inconel 718

包含压敏电阻元件的低压交流电涌保护器失效模式分析

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现代建筑电气 2016年第11期7卷 13-16页

作者：李天密鲍舒耕黄贵君任怡赵强杨国华四川中光防雷科技股份有限公司四川成都611730

从压敏电阻(MOV)失效模式相关的电涌保护器(SPD)失效、SPD选用不合理导致的失效以及设计、制造不当及应用环境多样化造成SPD的失效方面分析了SPD的失效原因,并提出了相应的验证措施和解决方案,提高了包含MOV元件的低压交流SPD的可靠性,... 详细信息

从压敏电阻(MOV)失效模式相关的电涌保护器(SPD)失效、SPD选用不合理导致的失效以及设计、制造不当及应用环境多样化造成SPD的失效方面分析了SPD的失效原因,并提出了相应的验证措施和解决方案,提高了包含MOV元件的低压交流SPD的可靠性,从而更好地为电力系统和设备提供可靠的安全防护。

关键词：电涌保护器失效模式结构性破坏失效可靠性

A novel adaptive pigeon-inspired optimization algorithm based on evolutionary game theory

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Science China(Information Sciences) 2021年第3期64卷 241-242页

作者： Xingshuo HAI Zili WANG qiang FENG Yi ren Bo SUN Dezhen yang School of Reliability and Systems Engineering Beihang University

Dear editor,In pigeon-inspired optimization(PIO) algorithm [1], the computational process consists of two different stages that originate from the tools pigeons depending on during a flight. Based on this, its variant... 详细信息

关键词： Pigeon-inspired optimization, Global continuous optimization problems, Evolutionary game theory Adaptability Local optimum

3,4-seco-Isopimarane and 3,4-seco-pimarane diterpenoids from Callicarpa nudiflora

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Chinese Journal of Natural Medicines 2021年第8期19卷 632-640页

作者： HUANG Hang TANG Chun-Ping KE Chang-qiang SHU ren-Geng YE yang State Key Laboratory of Drug Research and Natural Products Chemistry Department Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China School of Pharmacy Jiangxi University of Traditional Chinese MedicineNanchang 330004China School of Life Science and Technology Shanghai Tech UniversityShanghai 201210China

A phytochemical investigation was carried out on the extract of a medicinal plant Callicarpa nudiflora,resulting in the characterization of five new 3,4-seco-isopimarane(1-5)and one new 3,4-seco-pimarane diterpenoid(6),together with four known *** structures of the new compounds were fully elucidated by extensive analysis of MS,1 D and 2 D NMR spectroscopic data,and time-dependent density functional theory(TDDFT)calculation of electronic circular dichroism(ECD)spectra,and DFT calculations for NMR chemical shifts and optical rotations.

关键词： Callicarpa nudiflora 3,4-seco-Isopimarane 3,4-seco-Pimarane TDDFT-ECD DFT calculation

Tunable metamaterial absorber based on resonant strontium titanate artificial atoms

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Journal of Materials Science & Technology 2021年第3期62卷 249-253页

作者： Xiaoming Liu Zhiyu ren Tian yang Luping Chen qiang Wang Ji Zhou Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819China Department of New Energy Science&Engineering School of MetallurgyNortheastern UniversityShenyang110819China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing100084China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China

Dynamic control of the absorption frequency and intensity of metamaterial absorbers has attracted considerable attention,and many kinds of tunable metamaterial absorbers have been ***,due to the integration of separate resonant unit and tunable unit,these designed metamaterial absorbers suffer from complex structure and low *** numerically and experimentally demonstrate a tunable metamaterial absorber composed of artificial dielectric atoms as both resonant and tunable unit arrayed periodically in the background matrix on the metallic *** insensitive and wide incident angle absorption band with simulated and experimental absorptivity of 99%and 96%at 9.65 GHz are achieved at room *** absorption frequency can be gradually modulated by temperature,however,the absorption intensity at working frequency remains near *** dielectric atoms based tunable metamaterial absorbers with simple structure have potential applications as tempe rature sensors and frequency selective thermal emitters.

关键词： unity Tunable metamaterial absorber based on resonant strontium titanate artificial atoms

Effect of cerium addition on non-metallic inclusions in a high-carbon chromium bearing steel

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Journal of Iron and Steel Research International 2023年第11期30卷 2254-2266页

作者： Hao Li qiang ren Li-feng Zhang State Key Lab of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina School of Mechanical Engineering Yanshan UniversityQinhuangdao066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing100144China

Effects of varied levels of cerium(28×10-6,65×10^(-6) and 150×10^(-6))on inclusions in a high-carbon chromium bearing steel at different stages(before adding cerium,after adding cerium for 1,5,10 min and ingot)were studied using laboratory *** automatic scanning electron microscope system with energy-dispersive spectroscopy was used to analyze the amount,composition,size and morphology of inclusions in the steel at different *** the cerium content in the molten steel increased from 0 to 150×10^(-6),the evolution sequence of inclusions was as follows:Al_(2)O_(3)→CeAl11O18→CeAlO_(3)→Ce_(2)O_(2)*** 28×10^(-6) cerium was added,Al_(2)O_(3) inclusions were modified into CeAl_(11)O_(18) inclusions in the molten steel and then were further transformed into Al2O3 and CeAlO3 inclusions in the solid steel during *** the addition of 65×10^(-6) cerium,inclusions in the molten steel were modified into CeAlO_(3) and a small number of Ce2O2S *** the addition amount of cerium increased to 150×10^(-6),inclusions were transformed to Ce_(2)O_(2)*** size of inclusions in the molten steel decreased obviously with cerium *** the other hand,the size of inclusions increased during the cooling process in solid steels of No.1 steel(with 28×10^(-6) cerium)and No.2 steel(with 65×10^(-6) cerium).During the cooling process,unmodified MnS inclusions were precipitated in the solid steel of No.1 steel and wrapped outside the Al2O3 and CeAlO_(3) inclusions to form large complex *** the cooling process of No.2 steel,the inclusion size of CeAlO_(3) increased due to the collision and *** the No.3 steel(with 150×10^(-6) cerium),the average size of inclusions decreased rapidly and remained at a lower size during the cooling process,which was beneficial to improving the fatigue life of the steel.

关键词： Cerium Inclusion Transformation High-carbon chromium bearing steel Modification

Retrospective analysis of the changes in the surgical treatment of benign prostatic hyperplasia during an 11-year period: a single-center experience

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Asian Journal of Andrology 2021年第3期23卷 294-299页

作者： Zhu-Feng Peng Jing Zhou Pan Song Lu-Chen yang Bo yang Zheng-Ju ren Lin-Chun Wang qiang Wei qiang Dong Department of Urology Institute of UrologyWest China HospitalSichuan UniversityChengdu 610041China

The present study aimed to determine whether the number of patients with symptomatic benign prostatic hyperplasia(BPH)who preferred surgery decreased during the past 11 years at our center(West China Hospital,Chengdu,China),and whether this change affected the timing of surgery and the physical condition of surgical *** retrospective study included 57557 patients with BPH treated from January 2008 to December *** these,5427 patients were treated *** patients were divided into two groups based on the time of treatment(groups 8-13 and groups 13-18).The collected data comprised the percentage of all patients with BPH who underwent surgery,baseline characteristics of surgical patients,rehabilitation time,adverse events,and hospitalization *** surgery rates in groups 8-13 and groups 13-18 were 10.5%and 8.5%(Prenal failure decreased from 15.0%to 10.6%(P<0.001)and from 5.2%to 3.1%(P<0.001),*** groups 8-13 and groups 13-18,the mean catheterization times were 4.0±1.7 days and 3_3±1.6 days(P<0.001),respectively,and the mean postoperative hospitalization times were 5.1±2.4 days and 4.2±1.8 days(P<0.001),*** incidences of unplanned second surgery and death reduced during the study *** surgery rate decreased over time,which suggests that medication was chosen over ***,the percentage of late complications of BPH also decreased over time,which indicates that the timing of surgery was not delayed.

关键词： benign prostatic hyperplasia surgery therapeutics transurethral resection of prostate