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扫描电镜和X射线能量色散谱仪在涂层脱落现象分析中的应用

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电镀与涂饰 2021年第17期40卷 1388-1392页

作者：刘漪涛王福光崔树林李航何德水北京新风航天装备有限公司北京100854 海装驻北京地区第二军事代表室北京100854

通过对某型ZM5铸造镁合金产品表面防热涂层脱落实际案例的分析,介绍了扫描电镜(SEM)和X射线能量色散谱仪(EDS)在该类现象分析中的应用方法。在该案例的分析中,首先使用SEM对涂层脱落界面分别进行低倍和高倍显微形貌观察,确定脱落界面的... 详细信息

通过对某型ZM5铸造镁合金产品表面防热涂层脱落实际案例的分析,介绍了扫描电镜(SEM)和X射线能量色散谱仪(EDS)在该类现象分析中的应用方法。在该案例的分析中,首先使用SEM对涂层脱落界面分别进行低倍和高倍显微形貌观察,确定脱落界面的位置以及各区域的粘接情况。而后利用EDS对脱落界面的粘接异常位置与粘接正常位置的表面元素成分进行分析。最终确定脱落界面上粘接异常位置过高的硫元素含量是导致涂层脱落的原因,而硫源自镁合金氧化处理槽液中硫酸镁的残留。

关键词：铸造镁合金防热涂层脱落扫描电镜 X射线能量色散谱仪微观形貌故障排除

管磨机齿轮变位系数与螺旋角的设计研究与探讨

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机械传动 2016年第1期40卷 165-168页

作者：贲道春王冬生王复光李晓平查文炜江苏鹏飞集团股份有限公司江苏海安226623 盐城工学院机械工程学院江苏盐城224051

从管磨机齿轮变位系数和螺旋角的设计分析入手,阐述了小变位、小滑动率差和小螺旋角的设计新理念。介绍了齿轮总变位系数的分配方法和螺旋角选择注意点。通过分析计算和应用实践对比,得出结论：基于计算机编程计算,可求得总变位系数分... 详细信息

从管磨机齿轮变位系数和螺旋角的设计分析入手,阐述了小变位、小滑动率差和小螺旋角的设计新理念。介绍了齿轮总变位系数的分配方法和螺旋角选择注意点。通过分析计算和应用实践对比,得出结论：基于计算机编程计算,可求得总变位系数分配的优化值。即使滑动率差Δη极低,降低滑动磨损,又有较高的重合度,使接触应力较低,

关键词：管磨机齿轮变位系数螺旋角重合度滑动率差

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The Dynamics of a Stochastic SEITR Model for Tuberculosis with Incomplete Treatment

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 99-113页

作者： Xiao-dong wang Kai wang Department of Medical Engineering and Technology Xinjiang Medical UniversityUrumqiXinjiang 830017China

In this paper,a stochastic SEITR model is formulated to describe the transmission dynamics of tuberculosis with incompletely *** conditions for the existence of a stationary distribution and extinction are *** addition,numerical simulations are given to illustrate these analytical *** and numerical results show that large environmental perturbations can inhibit the spread of tuberculosis.

关键词： tuberculosis stationary distribution extinction

Co-doped cryptomelane-type manganese oxide in situ grown on a nickel foam substrate for high humidity ozone decomposition

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Journal of Environmental Sciences 2025年第2期148卷 529-540页

作者： Haoyuan Liang Xu wang Hui wang Zhenping Qu Key Laboratory of Industrial Ecology and Environmental Engineering School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China

Monolithic catalysts with excellent O_(3)catalytic decomposition performance were prepared by in situ loading of Co-doped KMn_(8)O_(16)on the surface of nickel *** triple-layer structure with Co-doped KMn_(8)O_(16)/Ni6MnO_(8)/Ni foam was grown spontaneously on the surface of nickel foam by tuning the molar ratio of KMnO_(4)to Co(NO_(3))_(2)·6H_(2)O ***,the formed Ni6MnO_(8)structure between KMn_(8)O_(16)and nickel foam during in situ synthesis process effectively protected nickel foam from further etching,which significantly enhanced the reaction stability of *** optimum amount of Co doping in KMn_(8)O_(16)was available when the molar ratio of Mn to Co species in the precursor solution was 2:*** the Mn2Co1 catalyst had abundant oxygen vacancies and excellent hydrophobicity,thus creating outstanding O_(3)decomposition *** O_(3)conversion under dry conditions and relative humidity of 65%,90%over a period of 5 hr was 100%,94%and 80%with the space velocity of 28,000 hr^(−1),*** in situ constructed Co-doped KMn_(8)O_(16)/Ni foam catalyst showed the advantages of low price and gradual applicability of the preparation process,which provided an opportunity for the design of monolithic catalyst for O_(3)catalytic decomposition.

关键词： Co-doped cryptomelane-type manganese O3 decomposition High humidity Nickel foam Monolithic catalyst

Fresh insights into the onset of big mantle wedge beneath the North China Craton

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Acta Geochimica 2025年第1期44卷 145-162页

作者： Yingpeng wang Xuance wang Wen Zhang Xiaowei Yu Ligong wang Jinhui wang Peigang Zhu Yongbin wang Shandong Institute of Geological Survey Ji’nan 250014People’s Republic of China Yunnan Key Laboratory of Earth System Science Yunnan UniversityEast Outer Ring RoadChenggong DistrictKunming 650500Yunnan ProvincePeople’s Republic of China Key Laboratory of Critical Minerals Metallogeny in Universities of Yunnan Province Yunnan UniversityKunming 650500People’s Republic of China Radiogenic Isotope Facility School of Earth and Environment SciencesUniversity of QueenslandBrisbaneQLD 4072Australia

The onset of the big mantle wedge(BMW)structure beneath the North China Craton remains *** on the genesis of Late Mesozoic granites associated with gold deposits in the Jiaodong Peninsula above the BMW could provide fresh insights into this *** monzogranite from the Zhaoxian-Shaling gold district was intruded during 154-148 *** I-type granite has high-K calc-alkaline and metaluminous *** monzogranite formed at medium temperatures(718-770℃)and was generated in a thickened lower crust at depths within the stability field of *** monzogranite’s high zircon Ce^(4+)/Ce^(3+)and Eu_(N)/Eu_(N)^(*)values and low FeOT/MgO ratios,suggest that it formed in a high oxygen *** variableε_(Hf)(t)values with T_(DM2)of 1.93-2.87 Ga imply that it originated from the melting of ancient crust basement,with contributions from mantle-derived *** granite’s enrichment in LREEs and LILEs,and depletion in HREEs and HFSEs,along with its trace element tectonic discrimination diagrams and medium Sr/Y,indicate an adakite affinity in an active continental margin *** transition from S-type granites to I-type granites and finally to A-type granites observed in the eastern part of North China Craton suggests a shift in the tectonic environment from compression to *** change is also reflected in the transition from flat subduction to steep ***,the monzogranite was formed in a tectonic transition setting triggered by a change in the subduction angle of the PaleoPacific Ocean slab during the Late *** event may have marked the initiation of the BMW above the North China Craton.

关键词： Zircon U-Pb age Hf isotopic composition Jiaodong Peninsula North China Craton

No-go guide for the Hubble tension:Late-time or local-scale new physics

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 73-85页

作者： Lu Huang Shao-Jiang wang wang-Wei Yu CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of Sciences(CAS)Beijing100190China Asia Pacific Center for Theoretical Physics(APCTP) Pohang37673Korea Max-Planck-Institut für Gravitationsphysik(Albert-Einstein-Institut) HannoverD-30167Germany Leibniz Universität Hannover Hannover30167Germany

The standard model of modern cosmology might be cracked by the recent persistent hot debate on the Hubble-constant(H_(0))tension,which manifests itself as the sound-horizon(r_(s))tension or absolute-magnitude(M_(B))tension if deeming the origin of the Hubble tension from modifying the early or late Universe,*** this study,we achieve a fully model-independent constraint(fitting a model-independent global parameterization to a model-independent inverse distant ladder with a modelindependent high-redshift calibration)on late-time models with strong evidence against homogeneous new physics over theΛ-cold-dark-matter(ΛCDM)*** using this model-independent constraint to calibrate sufficiently local supernovae with corresponding late-time models extrapolated below the homogeneity scale,we find surprisingly that,although both H_(0)tension and MB tension are absent in our local Universe,a combination of H_(0)and M_(B)as the intercept a B of the magnitude-redshift relation exhibits 3~7σtension even for theΛCDM *** aBtension seems to call for local-scale inhomogeneous new physics disguised as local observational systematics.

关键词： Hubble constant inverse distance ladder local Universe

Real-road NO_(x)and CO_(2)emissions of city and highway China-6 heavy-duty diesel vehicles

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Journal of Environmental Sciences 2025年第3期149卷 330-341页

作者： Zihao Ge Wanyang Li Junfang wang Yachao wang Ying Huang Xin wang Yunshan Ge School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Weichai Power Co.Ltd. Weifang 261061China Chinese Research Academy of Environmental Sciences Beijing 100012China

The emission of heavy-duty vehicles has raised great concerns *** complex working and loading conditions,which may differ a lot from PEMS tests,raised new challenges to the supervision and control of emissions,especially during real-world ***-board diagnostics(OBD)technology with data exchange enabled and strengthened the monitoring of emissions from a large number of heavy-duty diesel *** paper presents an analysis of the OBD data collected from more than 800 city and highway heavy-duty vehicles in China using remote OBD data ***-world NO_(x)and CO_(2)emissions of China-6 heavy-duty vehicles have been *** results showed that city heavy-duty vehicles had higher NO_(x)emission levels,which was mostly due to longer time of low SCR temperatures below 180°*** application of novel methods based on 3BMAWalso found that heavy-duty diesel vehicles tended to have high NO_(x)emissions at ***,little difference had been found in work-based CO_(2)emissions,and this may be due to no major difference were found in occupancies of hot running.

关键词： Remote monitor On-Board diagnostics NO_(x)emission CO_(2)emission Heavy-duty vehicles

Quickly obtaining densely dispersed coherent particles in steel matrix and its related mechanical property

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 111-118页

作者： Xiaoxiao wang Qingsong Huang School of Chemical Engineering Sichuan UniversityChengdu 610065China

Densely distributed coherent nanoparticles(DCN)in steel matrix can enhance the work-hardening ability and ductility of steel *** the routes to this end can be generally classified into the liquid-solid route and the solid-solid ***,the formation of DCN structures in steel requires long processes and complex *** far,obtaining steel with coherent particle enhancement in a short time remains a bottleneck,and some necessary steps remain ***,we show a high-efficiency liquid-phase refining process reinforced by a dynamic magnetic ***-Y-Mn-O particles had an average size of around(3.53±1.21)nm and can be obtained in just around 180 *** small nanoparticles were coherent with the matrix,implying no accumulated dislocations between the particles and the steel *** findings have a potential application for improving material machining capacity,creep resistance,and radiation resistance.

关键词： ferritic steels coherent particles microstructure compression test work hardening

Impact of Startup Strategy and Buffer Tank Volume on the Compressor Inlet State for a 3-MW sCO_(2)Brayton Cycle

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Journal of Thermal Science 2025年第1期34卷 159-175页

作者： ZHAO Decai wang Bo Key Laboratory of Advanced Energy and Power Institute of Engineering Thermophysics(IET)Chinese Academy of Sciences(CAS)Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China

The supercritical carbon dioxide(sCO_(2))Brayton cycle system has become an emerging and highly promising method of thermal power conversion due to its efficiency advantage,system compactness,and excellent adaptability of the heat *** the low carbon sCO_(2)Brayton cycle testbed with cycle output power approaching 3 MW,a relatively detailed dynamic simulation model of the entire system is constructed to explore the dynamic response characteristics of the system with different startup strategies and different buffer tank volumes during the startup *** simulation results indicate that the smaller the volume of the buffer tank,the more rapid and obvious the parameter fluctuation in the buffer tank during the *** the allowable relative deviation limit of density is 5%,then the ratio of the buffer tank volume to the volume of the entire closed loop should not be lower than 36.80%.The strategy of simultaneous temperature and speed increase during turbine bypass start can effectively reduce the fluctuation of compressor inlet parameters and reach the steady-state more *** paper provides the recommended matching table for the opening of the turbine bypass valve(TBV)and the main regulating valve(MGV)to reduce the parameter fluctuation during the bypass *** effectiveness of the proposed turbine bypass and bypass switching startup strategy is verified by simulation,which may be used as a reference for test bench's future debugging and operation.

关键词： sCO_(2)Brayton cycle dynamic model buffer tank startup strategy dynamic characteristic