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地球物理学报 1997年第4期40卷 481-486页

作者：徐元芳 d.r.barraclough d.J.Kerridge 中国科学院地球物理研究所北京100101 BritishGeologicalSurvey

利用卫星观测的长波磁异常，用等效偶极源方法推导了中国地区的视磁化强度分布．因卫星的高度远大于磁性地壳的厚度，将视磁化强度转换成磁化强度的垂直积分，它代表地壳内磁性物质的区域变化，利用视磁化强度与地表热流相应关系，计算... 详细信息

利用卫星观测的长波磁异常，用等效偶极源方法推导了中国地区的视磁化强度分布．因卫星的高度远大于磁性地壳的厚度，将视磁化强度转换成磁化强度的垂直积分，它代表地壳内磁性物质的区域变化，利用视磁化强度与地表热流相应关系，计算了中国的新疆和东部一些地区居里等温面的深度．新疆地区的居里面深度为35-50km，其分布形态与塔里木盆地和准噶尔盆地的地貌比较相似；中国东部一些地区居里面深度在20-40km之间，与一些作者用航磁等数据得到的居里深度十分接近．

关键词：居里深度地壳磁化强度模型

Simple collective model for nuclear chiral mode

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Frontiers of physics 2024年第2期19卷 1-5页

作者： r.V.Jolos E.A.Kolganova d.r.Khamitova Joint Institute for Nuclear research 141980 DubnaMoscow regionRussia dubna State University 141982 DubnaMoscow RegionRussia

A simple semi-analytical collective model that takes into account the limitations of the variation interval of the collective variable is suggested to describe the chiral dynamics in triaxial odd−odd nuclei with a fixed particle−hole *** collective Hamiltonian is constructed with the potential energy obtained using the postulated ansatz for the wave function symmetric with respect to chiral *** diagonalizing the collective Hamiltonian the wave functions of the lowest states are obtained and the evolution of the energy splitting of the chiral doublets in transition from chiral vibration to chiral rotation regime is demonstrated.

关键词： collective model nuclear chiral

中国地区MAGSAT卫星标量和矢量磁异常图

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空间科学学报 1992年第2期12卷 123-128页

作者：安振昌徐元芳王月华 d.r.barraclough d.J.Kerridge 中国科学院地球物理研究所北京100101 英国地质调查局

使用MAGSAT卫星资料,编绘中国及邻近地区的卫星磁异常图(10°N—60°N,70°E—140°E)。为了提取地壳异常场,必须从观测资料中消除主磁场、磁层场,感应场和电离层场。本文选用GSFC(12/83)地磁场模型,消除主磁场,磁层场和感应场。为了进... 详细信息

使用MAGSAT卫星资料,编绘中国及邻近地区的卫星磁异常图(10°N—60°N,70°E—140°E)。为了提取地壳异常场,必须从观测资料中消除主磁场、磁层场,感应场和电离层场。本文选用GSFC(12/83)地磁场模型,消除主磁场,磁层场和感应场。为了进一步消除电离层场的影响,改善相邻轨道磁异常的一致性,用纬度的二次多项式拟合每一条轨道的初始地壳异常,并从初始地壳磁异常值减去这一拟合值,从而获得最后的地壳异常值(△X,△Y,△Z,△F)。把研究地区分成1°×1°的网格,将每个网格内的磁异常进行平均,以获得网格中心点的异常值。根据这些网点值绘制中国及邻近地区的卫星标量和矢量磁异常图。等值线间隔为2nT。为了检验卫星磁异常图的可靠性,将卫星资料分成黎明组、黄昏组和联合组,分别进行处理和绘制卫星磁异常图。结果表明:根据上述资料绘制的卫星磁异常图有很好的一致性。中国地区的卫星磁异常值位于—10nT—10nT。卫星磁异常与区域构造特征有较好的一致性;塔里木地台、扬子地台和中朝地台是正磁异常区,西藏高原是负磁异常区。卫星磁异常反映出下地壳磁化强度的横向不均匀性。

关键词：卫星地壳磁异常卫星磁异常图

Ion heat transport in electron cyclotron resonance heated L-mode plasma on the T-10 tokamak

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Plasma Science and Technology 2024年第4期26卷 52-60页

作者： V.A.KrUPIN M.r.NUrGALIEV A.r.NEMETS I.A.ZEMTSOV S.d.SUNTSOV T.B.MYALTON d.S.SErGEEV N.A.SOLOVEV d.V.SArYCHEV d.V.rYJAKOV S.N.TUGArINOV N.N.NAUMENKO National research Centre“Kurchatov Institute” Moscow 123182Russia Bauman Moscow State Technical University Moscow 105005Russia Institution“Project Center ITEr” Moscow 123098Russia JSC“SOLAr” Minsk 220034Belarus

Anomalous ion heat transport is analyzed in the T-10 tokamak plasma heated with electron cyclotron resonance heating(ECrH) in second-harmonic extra-ordinary mode. Predictive modeling with empirical scaling for Ohmical heat conductivity shows that in ECrH plasmas the calculated ion temperature could be overestimated, so an increase of anomalous ion heat transport is required. To study this effect two scans are presented: over the EC resonance position and over the ECrH power. The EC resonance position varies from the high-field side to the low-field side by variation of the toroidal magnetic field. The scan over the heating power is presented with on-axis and mixed ECrH regimes. discharges with high anomalous ion heat transport are obtained in all considered regimes. In these discharges the power balance ion heat conductivity exceeds the neoclassical level by up to 10 times. The high ion heat transport regimes are distinguished by three parameters: the ratio Te/Ti, the normalized electron density gradient r/■, and the ion–ion collisionality νii~*. The combination of high Te/Ti, high νii~*, and r/■=6-10 results in values of normalized anomalous ion heat fluxes up to 10 times higher than in the low transport scenario.

关键词： tokamak L-mode electron cyclotron resonance heating ion heat transport

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： K.d.Küntz d.Koutroumpa W.r.dunn A.Foster F.S.Porter d.G.Sibeck B.Walsh The Henry A.rowland department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space Flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Uncovering Microstructure-Property relationship in Ni-Alloyed Fe-Mn-Al-C Low-density Steel Treated by Hot-rolling and Air-Cooling Process

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 713-725页

作者： Xiaoliang Jia Guhui Gao Xiaolu Gui Chun Feng r.d.K.Misra Bingzhe Bai School of Mechanical Electronicand Control EngineeringBeijing Jiaotong UniversityBeijing100044China CNPC Tubular Goods research Institute Xi’an710077China Laboratory for Excellence in Advanced Steel research University of Texas at El PasoEl PasoTX79968-0521USA School of Material Science and Engineering Key Laboratory of Advanced Materials of Ministry of EducationTsinghua UniversityBeijing100084China

This paper focuses on the relationship between the microstructure and tensile properties of Fe-Mn-Al-C low-density high-strength steel processes by hot-rolling and air-cooling process. The microstructure analysis reveals that the combination of hot-rolling and air-cooling results in the formation of heterogeneous structures comprising different-sized γ and B_(2) phases in the low-density steel with the addition of nickel (Ni). The addition of Ni promotes the formation of the B_(2) phase and induces the pinning of B_(2) phase particles at the γ grain boundaries. This pinning effect effectively hinders the growth of the γ grains, leading to grain refinement. The tensile test results demonstrate that LdS-5Ni (low-density steel, LdS) exhibits excellent high strength and ductility combination, e.g., a tensile strength of 1535 MPa, yield strength of 1482 MPa, and elongation of 23.3%. These remarkable mechanical properties are primarily attributed to the combined strengthening contributions of grain refinement and duplex nano-sized second-phase precipitation hardening.

关键词： Low-density steel Microstructure B_(2)phase κ-Carbide Tensile properties

Influence of Component Size on the Corrosion Behavior of Ti6Al4V Alloy Fabricated by Electron Beam Powder Bed Fusion

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 159-168页

作者： Hongyu Zheng Xin Gai Yun Bai Wentao Hou Shujun Li Yulin Hao r.d.K.Misra rui Yang Institute of Metal research Chinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China Nuclear Power Institute of China Chengdu610213China department of Metallurgical Materialsand Biomedical EngineeringThe University of Texas at El Paso500WUniversity AvenueEl PasoTX79968USA

The electrochemical behavior of Ti-6Al-4V with 1 mm and 16 mm thickness prepared by electron beam powder bed fusion(EB-PBF)was investigated in phosphate buffered *** results showed that EB-PBF Ti-6Al-4V with a larger component size was more resistant to corrosion compared to the smaller component,because of less acicularαʹphase content and moreβphase *** a non-equilibrium phase in the“high-energy state”,αʹphase has a greater susceptibility to corrode and reduces the corrosion resistance of the material,whileβphase improves corrosion resistance of titanium *** results show that the phase composition has a more significant effect on the corrosion performance than the grain size.

关键词： Electron beam powder bed fusion Ti6Al4V alloy Corrosion resistance Component size Polarisation

Spatiotemporal dynamics in butterfly hybrid zones

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Insect Science 2024年第2期31卷 328-353页

作者： Ananda r.Pereira Martins Natalie B.Warren W.Owen McMillan rowan d.H.Barrett redpath Museum McGill University859 Sherbrooke Street WestMontrealQuebecCanada Smithsonian Tropical researchInstitute GamboaPanama CityPanama

Evaluating whether hybrid zones are stable or mobile can provide novelinsights for evolution and conservation biology. Butterflies exhibit high sensitivity to envi-ronmental changes and represent an important model system for the study of hybrid zoneorigins and maintenance. Here, we review the literature exploring butterfly hybrid zones,with a special focus on their spatiotemporal dynamics and the potential mechanisms thatcould lead to their movement or stability. We then compare different lines of evidenceused to investigate hybrid zone dynamics and discuss the strengths and weaknesses ofeach approach. Our goal with this review is to reveal general conditions associated withthe stability or mobility of butterfly hybrid zones by synthesizing evidence obtained us-ing different types of data sampled across multiple regions and spatial scales. Finally, wediscuss spatiotemporal dynamics in the context of a speciation/divergence continuum, therelevance of hybrid zones for conservation biology, and recommend key topics for futureinvestigation.

关键词： butterflies human impacts hybrid zones movement spatiotemporaldynamics stability

Excellent photoluminescence and electrochemical properties of Sm^(3+) doped Ca_(2)MgSi_(2)O_(7) nanophosphor:display and electrochemical sensor applications

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Journal of rare Earths 2024年第6期42卷 1046-1055,I0002页

作者： r.B.Basavaraj K.Sureshkumar d.P.Aarti M.B.Madhusudana reddy G.Nagaraju T.ramakrishnappa G.r.Navyashree K.r.Venkatesha Babu K.S.Hemalatha department of Physics BMS Institute of Technology and ManagementBangalore560064India department of Chemistry BMS Institute of Technology and ManagementBangalore560064India department of Chemistry School of Applied SciencesREVA UniversityBangalore560064India Energy Materials researchLaboratory Department of ChemistrySiddaganga Institute of TechnologyTumakuru57203KarnatakaIndia School of Physical Sciences REVA UniversityBangalore560057Indi department of Physics Govt.Science CollegeBengaluru560001India department of Physics Maharani Science College for WomenMaharani Cluster UniversityBengaluru560001India

A series of orange-red light emitting Ca_(2)MgSi_(2)O_(7):Sm^(3+)nanopowders were fabricated via low-cost ecofriendly green combustion technique using Aloe vera gel as *** phase purity of the samples were confirmed by the powder X-ray diffraction(PXrd)*** single-phase tetragonal structure is observed from the PXrd results with no additional impurity *** band gap energy of the fabricated powders was estimated by diffuse reflectance spectra(drS)and is found to be in the range of 4.01-5.98 eV.A high resolution scanning electron microscope(SEM)was used to study the morphological behaviour of the ***-like structures are observed from the SEM *** particle size was evaluated by transmission electron microscopy(TEM)and is found to be~50 *** interplanar distance is found to be 0.53 *** properties were systematically studied in *** phosphors are successfully excited at 403 nm NUV light,producing reddish-orange characteristic *** emission peaks are centered at 558(^(4)G_(5/2)→^(6)H_(5/2)),607(^(4)G_(5/2)→^(6)H_(7/2))and 645 nm(^(4)G_(5/2)→^(6)H_(9/2)),*** the observed peaks the red emanation(^(4)G_(5/2)→^(6)H_(7/2))is stronger than the orange emission(^(4)G_(5/2)→^(6)H_(5/2))in the current *** photoluminescent concentration quenching is noticed above 5 mol%Sm^(3+)ion doping *** dipole-dipole interaction resulting in cross relaxation is found to be the principal cause of concentration quenching *** color features such as Commission Internationale de I’Eclairage(CIE)and correlated color temperature(CCT)were studied in *** optimized chromaticity coordinates were estimated to be(0.6363,0.3632),which fall in the reddish-orange *** average CCT value obtained is 3362 *** average color purity is found to be~82%.Sm^(3+)incorporated Ca_(2)MgSi_(2)O_(7) samples are possible contender for single white light generation commercial candidates owing to

关键词： Green combustion Photoluminescence Orange-red emission Color purity Sensors rare earths