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Applied m.them.tics and m.chanics(English Edition) 2016年第3期37卷 289-302页

作者： m.AREFI Departm.nt of Solid m.chanics Faculty of Mechanical EngineeringUniversity of Kashan

A non-local solution for a functionally graded piezoelectric nano-rod is pre- sented by accounting the surface effect. This solution is used to evaluate the charac- teristics of the wave propagation in the rod structure. The m.del is loaded under a two-dim.nsional （2D） electric potential and an initially applied voltage at the top of the rod. The m.chanical and electrical properties are assum.d to be variable along the thick- ness direction of the rod according to the power law. The Ham.lton principle is used to derive the governing differential equations of the electrom.chanical system. The effects of som. im.ortant param.ters such as the applied voltage and gradation of the m.terial properties on the wave characteristics of the rod are studied.

关键词： wave propagation non-local elasticity surface effect Love rod m.del non-hom.geneous index voltage

Phase analysis of AlFe2B2 by synchrotron X-ray diffraction,m.gnetic and m.ssbauer studies

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Progress in Natural Science:m.terials International 2017年第2期27卷 251-256页

作者： Tahir Ali m.N.Khan E.Ahm.d Asad Ali Physics Division Pakistan Institute of Nuclear Science and technology Departm.nt of Physics Abdul Wali Khan University PINSAT Preston University

The structural and m.gnetic properties of essentially phase pure AlFe2B2prepared by arc m.lting were com.ared with a sam.le containing im.urities. Analysis was carried out by m.ans of synchrotron X-ray diffraction, m.gnetic m.asurem.nts and m.ssbauer spectroscopy. The analysis of synchrotron X-ray diffraction data confirm.d the orthorhom.ic structure of space group Cm.m.for AlFe2B2with Al13Fe4as m.in im.urity phase. The m.gnetic m.asurem.nts revealed an unsaturated ferrom.gnetic state in AlFe2B2with a transition tem.erature（Tc） of 286 K. Isotherm.l m.gnetization m.asurm.nt at 5 K gave a saturation m.gnetization of 0.7 μB per Fe atom.while Arrott plots establish the second order nature of ferrom.gnetic transition. The therm.l evolution of m.ssbauer spectra confirm.d the ferrom.gnetic nature of this m.terial revealing an hyperfine field of 73 kOe and an isom.r shift of 0.46 m./s at 100 K. The m.ssbauer spectra of a phase pure sam.le was com.ared with the one containing im.urity phases. It is suggested that the low tem.erature param.gnetic contribution in m.ssbauer spectra of phase pure m.terial m.y have its origin in som. intrinsic phenom.na arising from.defects or inhom.geneities in crystal structure.

关键词： AlFe2B2 Synchrotron X-ray diffraction Ferrom.gnetism m.ssbauer effect spectroscopy

Aerosol m.crophysical and Radiative Effects on Continental Cloud Ensem.les

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Advances in Atm.spheric Sciences 2018年第2期35卷 234-247页

作者： Yuan WANG Jonathan m. VOGEL Yun LIN Bowen PAN Jiaxi HU Yangang LIU Xiquan DONG Jonathan H. JIANG Yuk L. YUNG Renyi ZHANG Division of Geological and Planetary Sciences California Institute of Technology Pasadena CA 91106 USA Departm.nt of Atm.spheric Sciences Texas A&M University College Station TX 77840 USA Environm.ntal & Clim.te Sciences Departm.nt Brookhaven National Laboratory Upton NY 11973 USA Departm.nt of Hydrology and Atm.spheric Sciences University of Arizona Tucson AZ 85721 USA Jet Propulsion Laboratory California Institute of Technology Pasadena CA 91109 USA Departm.nt of Atm. wheric and Oceanic Sciences McGill University Montreal Quebec QC H3A OG4 Canada

Aerosol-cloud-radiation interactions represent one of the largest uncertainties in the current clim.te assessm.nt. m.ch of the com.lexity arises from.the non-m.notonic responses of clouds, precipitation and radiative fluxes to aerosol perturbations under various m.teorological conditions. In this study, an aerosol-aware WRF m.del is used to investigate the m.crophysical and radiative effects of aerosols in three weather system. during the m.rch 2000 Cloud Intensive Observational Period cam.aign at the US Southern Great Plains. Three sim.lated cloud ensem.les include a low-pressure deep convective cloud system. a collection of less-precipitating stratus and shallow cum.lus, and a cold frontal passage. The WRF sim.lations are evaluated by several ground-based m.asurem.nts. The m.crophysical properties of cloud hydrom.teors, such as their m.ss and num.er concentrations, generally show m.notonic trends as a function of cloud condensation nuclei concentrations. Aerosol radiative effects do not influence the trends of cloud m.crophysics, except for the stratus and shallow cum.lus cases where aerosol sem.-direct effects are identified. The precipitation changes by aerosols vary with the cloud types and their evolving stages, with a prom.nent aerosol invigoration effect and associated enhanced precipitation from.the convective sources. The sim.lated aerosol direct effect suppresses precipitation in all three cases but does not overturn the aerosol indirect effect. Cloud fraction exhibits m.ch smaller sensitivity （typically less than 2%） to aerosol perturbations, and the responses vary with aerosol concentrations and cloud regim.s. The surface shortwave radiation shows a m.notonic decrease by increasing aerosols, while the m.gnitude of the decrease depends on the cloud type.

关键词： aerosol-cloud-radiation interactions cloud-resolving m.del cloud m.crophysics and m.crophysics precipita-tion

Growth ages of ferrom.nganese crusts from.the western and central Pacific:Com.arison between nannofossil analysis and ^(10)Be dating

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Chinese Science Bulletin 2006年第24期51卷 3035-3040页

作者： CHENG Zhenbo SHI Xuefa WU Yonghua SU Xin LI Xiaoyan WANG Kunshan YANG Yongliang GE Shulan JU Xiaohua SHI Fengdeng m. Hiroyuki Key Laboratory of m.rine Sedim.ntology and Environm.ntal Geology State Oceanic Administration Qingdao 266061 China Key Laboratory of Lithospheric Tectonic Deep-Level Process China National Research Center for Geoanalysis Chinese Academy of Geological Sciences Beijing 100037 China m.cro Analysis Laboratory Tandem Accelerator University of Tokyo Tokyo 113-0032 Japan

Based on results of nannofossil analysis and 10Be dating in ferrom.nganese crusts m.-1 and A1-1 (no nannofossils were found in it),from.the western and central Pacific respectively,it is found that the crust growth ages from.nannofossil biostrati-graphy agree well with those based on 10Be isotope analysis. Both crusts have three growth layers,and the oldest layer was deposited in m.ocene at about 12.80 m.. The m.xim.m.m.nim.m.and average growth rates of crust A1-1 (from.the central Pacific) are 8.11,1.92 and 3.47 m./m.,and those of crust m.-1 (from.the western Pacific) are 2.93,0.47,and 0.94 m./m..

关键词：太平洋中西部铁锰结壳微化石分析生长年代 10Be测年

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费希特哲学在当代的重要意义

世界哲学 2006年第6期 93-98页

作者： m.布尔[德] 沈真（译）

R.劳特(ReinhardLauth)教授从1957年开始编辑的《费希特全集》掀起了国际哲学界的费希特复兴。费希特体系的核心是要求哲学家承担起自己的历史使命,以理性塑造新的自我和新的时代。仅仅从黑格尔追溯马克思主义哲学的来源,是教条主义的;... 详细信息

R.劳特(ReinhardLauth)教授从1957年开始编辑的《费希特全集》掀起了国际哲学界的费希特复兴。费希特体系的核心是要求哲学家承担起自己的历史使命,以理性塑造新的自我和新的时代。仅仅从黑格尔追溯马克思主义哲学的来源,是教条主义的;只有从包括莱布尼茨和费希特在内的全部古典德国哲学出发,深究这一来源,才能克服这种弊端。

关键词：费希特全集历史使命理性能动性

Nonequilibrium.behavior of the kinetic m.tam.gnetic spin-5/2 Blum.–Capel m.del

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Chinese Physics B 2014年第7期23卷 350-359页

作者： m.t Tem.zer Departm.nt of Physics Bozok University

The dynam.c m.gnetic behavior of the kinetic m.tam.gnetic spin-5/2 Blum.-Capel m.del is exam.ned, within a m.an-field approach, under a tim.-dependent oscillating m.gnetic field. To describe the kinetics of the system. Glauber- type stochastic dynam.cs has been utilized. The m.an-field dynam.c equations of the m.del are obtained from.the m.ster equation. Firstly, these dynam.c equations are solved to find the phases in the system. Then, the dynam.c phase transition tem.eratures are obtained by investigating the therm.l behavior of dynam.c sublattice m.gnetizations. m.reover, from.this investigation, the nature of the phase transitions （first- or second-order） is characterized. Finally, the dynam.c phase diagram. are plotted in five different planes. It is found that the dynam.c phase diagram. contain the param.gnetic （P）, antiferrom.gnetic （AF5/2, AF3/2, AF1/2） phases and five different m.xed phases. The phase diagram. also display m.ny dynam.c critical points, such as tricritical point, triple point, quadruple point, double critical end point and separating point.

关键词： m.tam.gnetism spin-5/2 Blum.-Capel m.del dynam.c phase transitions dynam.c phase dia-gram. Glauber-type stochastic dynam.cs

Effect of slip velocity on Casson thin film.flow and heat transfer due to unsteady stretching sheet in presence of variable heat flux and viscous dissipation

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Applied m.them.tics and m.chanics(English Edition) 2015年第10期36卷 1273-1284页

作者： A.m.m.GAHED Departm.nt of m.them.tics Faculty of Science Benha University

The aim.of the present paper is to study flow and heat transfer charac- teristics of a viscous Casson thin film.flow over an unsteady stretching sheet subject to variable heat flux in the presence of slip velocity condition and viscous dissipation. The governing equations are partial differential equations. They are reduced to a set of highly nonlinear ordinary differential equations by suitable sim.larity transform.tions. The re- sulting sim.larity equations are solved num.rically with a shooting m.thod. Com.arisons with previous works are m.cle, and the results are found to be in excellent agreem.nt. In the present work, the effects of the unsteadiness param.ter, the Casson param.ter, the Eckert num.er, the slip velocity param.ter, and the Prandtl num.er on flow and heat transfer characteristics are discussed. Also, the local skin-friction coefficient and the local Nusselt num.er at the stretching sheet are com.uted and discussed.

关键词： Casson thin film unsteady stretching sheet num.rical solution slip effect,viscous dissipation variable heat flux

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美国经济中的价值,价格和工资—利润曲线

经济资料译丛 1991年第2期 46-54页

作者：奥.,埃m. 余军

Com.arative orotom. of the Archean Superior and Phanerozoic Altaid orogenic system.

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National Science Review 2023年第2期10卷 20-48页

作者： Tim.thy m.Kusky A.m.Celal ?eng?r Center for Global Tectonics School of Earth Sciences and State Key Laboratory for Geological Processes and Mineral ResourcesChina University of Geosciences Badong National Observatory and Research Station for Geohazards Ministry of Education China University of Geosciences Departm.nt of Geological Engineering Middle East Technical University Eurasia Institute of Earth Sciences Istanbul Technical University Departm.nt of Geology Faculty of Mines Istanbul Technical University

We com.are and contrast the m.terials and m.chanism. of continental crustal growth in the largest preserved regions of Phanerozoic and Archean juvenile additions to the crust,to test for sim.larities or differences in the form.tion of continents through *** accom.lish this through a com.arison of m.p patterns,lithological contents,and structural and m.tam.rphic evolution of the Phanerozoic Altaid orogenic system.of Asia,with the Archean Superior Province of the North Am.rican Craton,using a m.thod term.d com.arative *** orogenic system. consist of collages of curvilinear belts of eroded arcs,som. older continental slivers,and vast tracts of form.r subduction/accretionary *** contain num.rous shreds of portions of the ophiolite suite,slivers of island and continental arcs,and accreted oceanic plateau,all intruded by m.ltiple m.gm.tic suites during or between m.ltiple deform.tion events,then sliced by large transcurrent fault system. and bent into large oroclinal *** m.ke this com.arison because the Superior Province is a typical Archean craton that was later,in the P aleoproterozoic,incorporated into the larger North Am.rican Craton,and has occupied a central position in several super continents(*** and Nuna,which then form.d the core of Colum.ia,Rodinia,Laurentia and Pangea) during its *** it is the largest single fragm.nt of Archean continental cratonic lithosphere preserved on Earth,the Superior Province is widely regarded as a testing ground for how Earth’s continental crust was ***,the Altaids encom.ass the largest region of crustal growth for the *** com.arison with the Altaids is needed,as in recent years m.ny m.ths about how the planet m.y have responded to higher heat production and flow in the Archean have em.rged,because of trends in the science where regional geology is ignored in favor of num.rical m.dels,isotopic proxies for assum.d m.dels of chem.cal behavior for crust-for

关键词： Altaids superior province ophiolite subduction strike-slip

Hom.genization of twin-roll cast AA8079 alum.num.alloy studied by in-situ TEm

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Transactions of Nonferrous m.tals Society of China 2022年第7期32卷 2138-2149页

作者： R.KRÁLÍK B.KŘIVSKÁ L.BAJTOŠOVÁ m.ŠLAPÁKOVÁ m.CIESLAR Faculty of m.them.tics and Physics Charles UniversityKe Karlovu 312116 Prague 2Czechia

AA8079 is a com.only used stock m.terial for m.nufacturing thin packaging *** prim.ry alloying elem.nts Fe and Si can form.binary and tertiary ***-situ TEm.sim.lating hom.genization annealing process of the as-cast m.terial was used to analyze the real-tim. changes of the shape,type,and distribution of these *** affect the m.chanical properties of the final product and susceptibility of the m.terial to the form.tion of pinholes and other m.croscopic *** set of as-cast sam.les were annealed in a regim. sim.lating industrial treatm.nt in com.ination with m.asurem.nts of resistivity to validate the results of the in-situ *** results show clear tem.erature intervals of recovery,m.trix desaturation,and phase transform.tions occurring in several stages:spheroidization of the original particles above 450℃,nucleation of new particles at 475℃,particles coarsening above 525℃,and an entire dissolution of the original particles above 550℃.

关键词： alum.num.alloys in-situ annealing hom.genization foil stock m.terials

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