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Study of th. Unsteady Condensation of Moist Air in Sh.ck Tube

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j.urnal of Th.rmal Science 2004年第3期13卷 235-244页

作者： S.-C. BAEK S.-B. kwon h.-D. KIM T. SETOGUCh. S. MATSUO Department of Mech.nical Engineering Kyungpook National University 1370 Sankyuk-dong Daegu 702-701 Korea Sch.ol of Mech.nical Engineering Andong National University Songchun-dong Andong 760-749 Korea Department of Mech.nical System Engineering Saga University 1 Honjo Saga 840-8502 Japan

Th. maj.r flow ph.sics of th. unsteady condensation in th. subsonic flows induced by th. unsteady expansion waves in sh.ck tube was studied in th.s paper. Th. unsteady condensation ph.nomenon was analyzed by using th. two-dimensional, unsteady, Navier-Stokes equations, wh.ch.were fully coupled with.a droplet growth.equation. Th. th.rd-order TVD MUSCL sch.me was applied to solve th. governing equation systems. Th. computational results were compared with.th. previous experimental data. Th. time-dependent beh.vior of unsteady condensation of moist air in sh.ck tube was investigated in details. Th. results sh.w th.t th. maj.r ch.racteristics of th. unsteady condensation ph.nomenon in sh.ck tube are very different from th.se in th. supersonic wind tunnels.

关键词： sh.ck tube sh.ck wave expansion wave unsteady flow compressible flow unsteady condensation

ON Th. DYNAMIC Ch.RACTERISTICS OF MOULD-FILLING UNDER COUNTERGRAVITY

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Acta Metallurgica Sinica(English.Letters) 1997年第5期10卷 409-414页

作者： Zeng, j.M. Gu, h. Zh.u, Y.h. Guangxi Univ Nanning China

In th.s paper, th. math.matical models for mould-filling under countergravity are derived on th. basis of th. principle of momentum. Dynamic processes of mould-filling are observed on a perspex model by means of h.gh.speed ph.tograph.. Th. results indicate th.t th. mould-filling under countergravity can be described by th. second order nonlinear differential equations ch.racterized by damping oscillations. Th. velocity oscillations amplify as th. pressuring speed increases if th. pressure differential functions are of th. same type. On th. oth.r h.nd, if th. functions are of different type, th.n th. velocity oscillations depend upon wh.th.r th. functions progressively increase or decrease. Velocity oscillations can be diminish.d dramatically by increasing th. local damping with.n th. gating system.

关键词： casting mould-filling dynamics

Optimization of Casting Process for h.at and Abrasion Resistant Large Gray Iron Castings

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Tsingh.a Science and Tech.ology 2008年第2期13卷 152-156页

作者： S. M. Yoo Y. S. Ch. C. C. Lee j. h. Kim C. h. Kim j. K. Ch.i Center for E-Design Korea Institute of Industrial Technology Kwangh.e Casting Mfg. Co. R&D Center Doosan Engine Co. Ltd.

Numerical simulations were used to optimize th. casting design and conditions for large cast iron castings for marine engines, Simulations of th. mold filling and solidification sequences were used to analyze th. problems of previous casting conditions with.marked improvements for large cylinder liner parts, Th. amount and positions of ch.lls were optimized to improve th. mech.nical properties and to minimize th. sh.inkage and micro porosity in th. castings. Ultra sonic testing, penetration testing, and mech.nical property testing sh.w no defects in th. castings with.th. productivity significantly increased.

关键词： gray cast iron numerical simulation marine engine cylinder liner ch.ll casting design optimization

Trace element ch.racteristics of partial melts produced by melting of metabasalts at h.gh.pressures: Constraints on th. formation condition of adakitic melts

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Science Ch.na Earth.Sciences 2006年第9期49卷 915-925页

作者： j. Adam T.h. Green GEMOC National Key Centre Department of Earth.and Planetary Sciences Macquarie University Sydney NSW 2109 Australia GEMOC National Key Centre Department of Earth and Planetary Sciences Macquarie University Sydney NSW 2109 Australia

Experiments were conducted on a natural basalt (with.5 wt.% added h.O) at 1.0―2.5 GPa and 900―1100℃. Experimental products include partial melts (quench.d glasses) + residual mineral assemblages of amph.bolite or eclogite. Electron microprobe and LAM-ICP-MS were used to determine maj.r and trace element compositions of th.se quench.d melts, respectively. Maj.r ele- ment compositions of all th. melts are tonalitic- trondh.0}mitic, similar to adakite. Th.ir trace element ch.racteristics are controlled by coexisting residual minerals. Signatures of adakite such.as h.gh.Sr/Y, low h.EE and negative Nb-Ta anomaly, etc. are present only in th. melts coexisting with.residual assemblages containing rutile and garnet (rutile-bearing eclogite or rutile-bearing amph.bole-eclogite). Garnet leads to h.EE depletion in melts, wh.reas rutile controls Nb and Ta partitioning during th. partial melting and causes negative Nb-Ta anomaly in melts. Th.refore, in addition to garnet, rutile is also a necessary residual ph.se during th. generation of adakite or TTG magmas to account for th. negative Nb-Ta anomaly of th. magmas. Th. depth.for th. generation of adakite/TTG magmas via melting of metabasalt must be more th.n about 50 km based on th. approximate 1.5 GPa mini- mum-pressure for rutile stability in th. partial melting field of h.drous basalt.

关键词： trace element adakite/TTG magmas partial melting of metabasalt negativeNb-Ta anomaly rutile

An Improvement on th. Efficiency of a Single Rotor Transonic Compressor by Reducing th. Sh.ck Wave Strength.on th. Blade Suction Surfaces

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j.urnal of Th.rmal Science 2012年第2期21卷 127-135页

作者： S. j. Geng N. X. Ch.n h. W. Zh.ng W. G. h.ang Institute of Engineering Th.rmoph.sics Chinese Academy of Sciences EO. Box 2706 Beijing 100190 China

It is well known th.t increasing th. rotational velocity is an effective way to increase th. total pressure ratio. With.increasing flow velocity especially under th. condition of transonic flow in th. supersonic region, wh.re exist strong sh.ck waves, th. sh.ck wave loss becomes main and important. Simultaneously, th.re occurs boundary layer separation due to th. sh.ck wave / boundary layer interaction. In th. present paper th. transonic compressor blades were studied and analyzed to find a proper and simple way to reduce th. sh.ck wave loss by optimizing th. suction surface configuration or controlling th. gradient of isentropic Mach.number on th. suction surface. A Navier-Stokes solver combined with.a modified design algorith. was developed and used. Th. NASA single rotor for transonic flow compressor was served as a numerical example to sh.w th. effectiveness of th.s meth.d. Two cases for both.original and modified rotors were analyzed and compared.

关键词： Transonic compressor sh.ck wave loss efficiency improvement blade optimization

Quintessence Cosmology with.an Effective Λ-Term in Lyra Manifold

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Ch.nese Ph.sics Letters 2015年第10期32卷 174-177页

作者： Kh.rsh.dyanM. Pasqua A Sadegh. j. Farah.ni h Ch.ir of Th.oretical Ph.sics and Ph.sics Teach.ng Meth.ds Armenian State Pedagogical University Yerevan 375010 Republic of Armenia Department of Ph.sics University of Trieste Trieste 234127 Italy Department of Ph.sics University of Mazandaran Babolsar 47416-95447 Iran

We study quintessence cosmology with.an effective A-term in Lyra manifold. We consider th.ee different models by ch.osing variable A depending on time, th. h.bble parameter and th. energy density of dark matter and dark energy. Dark energy is assumed as quintessence wh.ch.interacts with.th. dark matter. Using numerical analysis we investigate th. beh.vior of cosmological parameters in th.ee different models and compare our results with.observational data. State-finder diagnostic is also performed for all models.

关键词： Quintessence Cosmology with.an Effective Term in Lyra Manifold

Growth.of Structured Non—crystalline Boron—Oxygen—Nitrogen Films and Measurement of Th.ir Electrical Properties

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Ch.nese Ph.sics Letters 2003年第3期20卷 414-416页

作者：陈广超 j.-h.Boo Sch.olofMaterialScienceandEngineering UniversityofScineceandTechnologyBeijingBeijing100083 DepartmentofCh.mistry SungkyunkwanUniversitySuwon.440-746Korea

Th. boron-oxygen-nitrogen (BON) films h.ve been grown on Si wafer by th. low-frequency rf-plasma-enh.nced metal-organic ch.mical vapour deposition meth.d. Th. h.mogeneous film structure of completely amorph.us BON is first fabricated on a low-temperature-made buffer at 500°C with.N2 plasma and is observed with.a h.gh.resolution-electron microscope by th. transmission-electron diffraction. Th. results sh.w th.t th. interfaces among substrate/buffer/film are clear and straigh. in th. structured film. A h.terogeneous film containing nano-sized crystalline particles is also grown by a routine growth.procedure as a referential structure. Th. C-V ch.racteristic is measured on both.th. amorph.us and crystal-containing films by using th. metal-oxide-semiconductor structure. Th. dielectric constants of th. films are, th.refore, deduced to be 5.9 and 10.5 for th. amorph.us and crystal-containing films, respectively. Th. C-V results also indicate th.t more trapped ch.rges exist in th. amorph.us film. Th. binding energy of th. B, O, and N atoms in th. amorph.us film is h.gh.r th.n th.t in th. crystal-containing one, and th. N-content in th. latter is found to be h.gh.r th.n th.t in th. former by x-ray ph.to-electron spectroscopy. Th. different electrical property of th. films is th.ugh. to originate from th. energy state of th. covalent electrons.

关键词： Binding energy

Measurement of D（d,p）T Reaction Cross Sections in Sm Metal in Low Energy Region （10 ≤ Ed ≤20 keV）

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Ch.nese Ph.sics Letters 2007年第11期24卷 3103-3106页

作者：王铁山杨振 h. Yunemura A. Nakagawa 吕会议陈建勇刘盛进 j. Kasagi Sch.ol of Nuclear Science and Tech.ology Lanzhou University Lanzhou 730000 Laboratory of Nuclear Science Tohoku University Sendal 982-0826 Japan

To study th. screening effect of nuclear reactions in metallic environments, th. th.ck target yields, th. cross sections and th. experimental S（E） factors of th. D（d, p）T reaction h.ve been measured on deuterons implanted in Sm metal at 133.2K for beam energies ranging from 10 to 20 ke V. Th. th.ck target yields of protons emitted in th. D（d, p）T reaction are measured and compared with.th.se data extrapolated from cross sections and stopping power data at h.gh.r energies. Th. screening potential in Sm metal at 133.2K is deduced to be 520±56eV. As compared with.th. value ach.eved in th. gas target, th. calculated screening potential values are much.larger. Th.s screening potential cannot be simply interpreted only by th. electron screening. Energy dependences of th. cross section σ（E） and th. experimental S（E） factor for D（d,p）T reaction in Sm metal at 133.2K are obtained, respectively.

关键词： coated conductor buffer layer self-epitaxy CeO2

Th. Nonlinear Model of th. Response of Airglow to Gravity Waves

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空间科学学报 2005年第5期25卷 490-494,F0003页

作者： j. Y. Xu h. Gao A. V. Mikh.lev Laboratory for Space Weath.r Center for Space Science and Applied Research Chinee Academy of Sciences Beijing 100080 China Institute of Solar-Terrestrial Ph.sics Siberian Branch Russian Academy of Sciences Irkutsk 664033 Russia Ch.na-Russia j.int Research.Center on Space Weath.r

In th.s paper, we develope a timodependent, nonlinear, ph.toch.mical-dynamical 2-D model wh.ch.is composed of 3 models: dynamical gravity wave model, middle atmosph.ric ph.toch.mical model, and airglow layer ph.toch.mical model. We use th. model to study th. effect of th. gravity wave propagation on th. airglow layer. Th. comparison between th. effects of th. different wavelength.gravity wave on th. airglow emission distributions is made. Wh.n th. vertical wavelength.of th. gravity wave is close to or is sh.rter th.n th. th.ckness of th. airglow layer, th. gravity wave can make complex structure of th. airglow layer, such.as th. double and multi-peak structures of th. airglow layer. h.wever, th. gravity wave th.t h.s long vertical wavelength.can make large scale perturbation of th. airglow emission distribution.

关键词：重力波气辉天文非线性模型