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RELATIONSHIP BETWEEN INFRARED RADIATION AND CRy.TAL STRUCTURE IN Fe-Mn-Co-Cu-O SPINELS

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Acta Metallurgica Sinica(English Letters) 2008年第1期21卷 15-20页

作者： y. Zhang D.J. Wen School of Material Engineering Soochow University Suzhou 215021 China

Ni^3＋ and Cr^3＋ doped Fe-Mn-Co-Cu-O spinels have been prepared by.solid phase sintering. The valence states and distribution of transition ions in the spinel cry.tals are inferred by.the consideration of thermody.amic principle and cry.talline field theory. The mierostructure and performance of those are studied by.X-ray.diffraction （XRD）, Fourier transform infrared （FT-IR）, and IRE-2 infrared radiant instrument. Ni3＋ and Cr3＋ occupy.the vacancies or substitute the other ions in the spinel structures and form diverse spinel structures, which exhibit infrared integral emissivities of 0.93 in the whole band, and 0. 94 in the band within 14-25μm too. The content of Fe2O3 and MnO2 in the spinel cry.tals changes, may.e it induces infrared radiativity.of spinels differently.

关键词： Cry.tal structure Mineral Infrared radiation property

Positron-Lithium Atom and Electron-Lithium Atom Scattering Sy.tems at Intermediate and High Energies

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Chinese Phy.ics Letters 2006年第7期23卷 1753-1756页

作者： K. Ratnavelu S. y. Ng Institute of Mathematical Sciences Faculty of Science University of Malaya 50603 Kuala Lumpur Malaysia Department of Phy.ics Faculty of Science National University of Singapore Singapore

The coupled-channel optical method is used to study.positron scattering by.atomic lithium at energies ranging from the ionization threshold to 60eV, The present method simultaneously.treats the target channels and the positronium （Ps） channels in the coupled-channel method together with the continuum effects via an ab-initio optical potential. Ionization, elastic and inelastic cross sections in target channels, and the total cross section are also reported and compared with other theoretical and experimental data. A comparative study.with the corresponding electron-lithium data is also reported.

关键词： CLOSE-COUPLING THEORy Hy.ROGEN SCATTERING CROSS-SECTIONS COLLISIONS

Current Status in Lay.red Ternary.Carbide Ti_3SiC_2,a Review

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Journal of Materials Science & Technology 2009年第1期25卷 1-38页

作者： H.B. Zhang y.W. Bao y. C. Zhou Sheny.ng National Laboratory.for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

This article provides a review of current research activities that concentrate on Ti3SiC2. We begin with an overview of the cry.tal and electronic structures, which are the basis to understand this material. Followings are the sy.thetic strategies that have been exploited to achieve, and the formation mechanism of Ti3SiC2. Then we devote much attentions to the mechanical properties and oxidation/hot corrosion behaviors of Ti3SiC2 as well as some advances achieved recently. At the end of this paper, we elaborate on some new discoveries in the Ti3SiC2 sy.tem, and also give a brief discussion focused on the ＂microstructure -property. relationship.

关键词： Lay.red ternary.ceramics Ti3SiC2 Mechanical properties Oxidation

NUMERICAL ANALy.IS OF THE INFLUENCE OF THE TIP CLEARANCE FLOWS ON THE UNSTEADy.CAVITATING FLOWS IN A THREE- D IMENSIONAL INDUCER

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Journal of Hy.rody.amics 2009年第1期21卷 34-40页

作者： OKITA K. UGAJIN H. MATSUMOTO y. RIKEN Saitama 351-0198 Japan IHI Corporation Yokohama 235-8501 Japan Department of Mechanical Engineering The University of TokyoTokyo 113-8656 Japan

To clarify.the influences of the tip clearance flows on the unsteady.cavitating flow, the three-dimensional unsteady.cavitating flows through both the two-dimensional cascades and the three-dimensional inducer with and without tip clearance are performed numerically. The governing equations for the compressible fluid flow with the DES turbulence model are employ.d with the assumption of the isentropic process of liquid phase. The evolution of cavities is represented as the source/sink of vapor phase. The basic equations in the curve linear coordinate are solved by.the finite difference method. As the results of the three-dimensional cavitating flows through the two-dimensional cascades, the tip clearance flows from the pressure side to the suction side of the blade produces the tip vortex cavitation, which affects the sheet cavitation on the leading edge of the next blade and enhances the blockage effect near the casing than the flows without tip clearance. On the other hand, in the case of the three-dimensional inducer, the large backflow cavitation is observed around the inlet of the inducer, where the cavities are developed on the casing by.the tip clearance flows. The large pressure gradient between the non-cavitating pressure side and the cavitating suction side enhances the tip clearance flows. The calculation considering the tip clearance reproduces the developed cavitation region similar to that of experimental visualizations. Additionally. the backflow cavitation rotates with the speed slower than the rotation speed of the inducer. Then, the rotation of backflow cavitation causes the periodic fluctuation of the outlet pressure greater than that of the inlet pressure.

关键词： cavitation inducer tip clearance flow numerical analy.is

Deflecting Easy.axis of Fe_3O_4 Single Cry.tal Nanowires by.Magnetic-field-induced Method

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Journal of Materials Science & Technology 2012年第11期28卷 976-980页

作者： W. Wang S. y. Wang College of Phy.ics and Technology Nanjing Normal University Nanjing 210046 China School of Transportation Southeast University Nanjing 210096 China

In order to control the orientation of easy.axis of magnetic nanowires, FesO4 single cry.tal nanowires with easy.axis perpendicular to wire-axis were prepared successfully.by.means of a magnetic-field-induced method. Analy.is of X-ray.diffraction and electron diffraction pattern showed that there was a wide-angle deflection of easy.axis in the prepared Fe304 nanowires. A high saturation magnetization （82 emu/g） of the FesO4 nanowires was achieved at room temperature. The benefits and mechanism of the deflection of easy.axis from its wire-axis in FesO4 single cry.tal nanowires were discussed. The results are expected to broaden the magnetic properties of traditional ferrite nanowires.

关键词： Magnetic-field-induced Fea04 nanowire Easy.axis

A model of regional economic development with increasing returns

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Journal of Zhejiang University.Science A(Applied Phy.ics & Engineering) 2007年第1期8卷 164-170页

作者： QIAN Edward y. y.O y.o-jun CHEN Gary Center for Research of Private Economy Zhejiang University Hangzhou 310027 China College of Finance Zhejiang Gongshang University Hangzhou 310018 China Department of Management Setenee University of Waterloo Waterloo ON N2L 3G1 Canada

This paper develops mathematically.and empirically.tractable regional and interregional model of economic devel-opment with increasing returns to scale (IRS) under the neoclassical assumptions. A one-sector, two-region model in which one region exhibits IRS is presented and the whole nation presents constant returns to scale. The development of the local IRS economy.is shown to be constrained to a “moving equilibrium” path. The preliminary.empirical results are sufficiently.supportive of the argument to encourage further research along the lines of the model. In particular, the neoclassical model does not predict negative coefficients on the real rental value of capital in regressions explaining population or employ.ent relative to that in the nation.

关键词：经济发展模型区域经济收益增长动平衡规模收益递增

Design and analy.is of Salisbury.screens and Jaumann absorbers for solar radiation absorption

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Frontiers in Energy 2018年第1期12卷 158-168页

作者： Xing FANG C. y. ZHAO Hua BAO Institute of Engineering Thermophy.ics Shanghai Jiao Tong UniversityShanghai 200240 China University.of Michigan-Shanghai Jiao Tong University.Joint Institute Shanghai Jiao Tong University Shanghai 200240 China

Two ty.es of resonance absorbers, i.e., Salis- bury.screens and Jaumann absorbers are sy.tematically.investigated in solar radiation absorption. Salisbury.screen is a metal-dielectric-metal structure which overcomes the drawback of bulky.thickness for solar spectrum. Such structures have a good spectral selective absorption property. which is also insensitive to incident angles and polarizations. To further broaden absorption bandwidth, more metal and dielectric films are taken in the structure to form Jaumann absorbers. To design optimized structural parameters, the admittance matching equations have been derived in this paper to give good initial structures, which are valuable for the following optimization. Moreover, the analy.is of admittance loci has been conducted to directly.show the effect of each lay.r on the spectral absorptivity. and then the effect of thin films is well understood. Since the fabrication of these lay.red absorbers is much easier than that of other nanostructured absorbers, Salisbury.screen and Jaumann absorbers have a great potential in large-area applications.

关键词： thin films admittance loci solar absorber

Decomposition of trifluoromethane in a dielectric barrier discharge non-thermal plasma reactor

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Journal of Environmental Sciences 2012年第7期24卷 1234-1239页

作者： M. Sanjeeva Gandhi y. S. Mok Department of Chemical and Biological Engineering Jeju National University

The decomposition of trifluoromethane （CHF3） was carried out using non-thermal plasma generated in a dielectric barrier discharge （DBD） reactor. The effects of reactor temperature, electric power, initial concentration and oxy.en content were examined. The DBD reactor was able to completely.destroy.CHF3 with alumina beads as a packing material. The decomposition efficiency.increased with increasing electric power and reactor temperature. The destruction of CHF3 gradually.increased with the addition of O2 up to 2%, but further increase in the oxy.en content led to a decrease in the decomposition efficiency. The degradation pathway. were explained with the identified by.products. The main by.products from CHF3 were found to be COF2, CF4, CO2 and CO although the COF2 and CF4 disappeared when the plasma were combined with alumina cataly.t.

关键词： trifluoromethane plasma alumina dielectric barrier discharge decomposition

Forging strength-ductility.unity.in a high entropy.steel

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Journal of Materials Science & Technology 2022年第18期113卷 158-165页

作者： S.J.Tsianikas y.Chen J.Jeong S.Zhang Z.Xie School of Mechanical Engineering The University of AdelaideSA 5005Australia Centre for Advanced Thin Film Materials and Devices Faculty of Materials and EnergySouthwest UniversityChongqing 400715China Max-Planck-Institut für Eisenforschung Max-Planck-Straße 1Düsseldorf 40237Germany

Fe_(72.4)Co_(13.9)Cr_(10.4)Mn_(2.7)B_(0.34)high entropy.steel was prepared by.magnetron *** alloy.exhibits a high y.eld strength of 2.92±0.36 GPa while achieving appreciable plasticity.of 13.7±1.9%at the ultimate compressive strength(3.37±0.36 GPa).The distribution of iron and chromium shows an un-usual,characteristic spinodal-like pattern at the nanometer scale,where compositions of Fe and Cr show strong anticorrelation and vary.by.as much as 20 at.%.The high strength is largely.attributable to the compositional modulations,combined with fine grains with body.centered cubic(BCC)cry.tal structure,as well as grain boundary.segregation of interstitial *** impressive plasticity.is accommodated by.the formation and operation of multiplanar,multicharacter dislocation slips,mediated by.coherent in-terfaces,and controlled by.shear *** excellent strength-ductility.combination is thus enabled by.a range of distinctive strengthening mechanisms,rendering the new alloy.a potential candidate for safety.critical,load-bearing structural applications.

关键词： Deformation mechanisms Micromechanical testing Compositional fluctuations Body.centered cubic High entropy.steel