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An exceptional.y strengthened East Asian summer monsoon event between 19.9 and 17.1 ka BP recorded in a Hul. stal.gmite

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Science China Earth Sciences 2009年第3期52卷 360-368页

作者： l. R. EDWARDS Department of Geol.gy and Geophysics University of Minnesota Minneapolis

A stal.gmite-based isotope record (No. H82) from Nanjing Hul. Cave, spanning from 16.5 to 10.3 ka BP, provided strong evidence for a coherence rel.tion between the East Asian summer monsoon (EASM) and the North Atl.nt... 详细信息

关键词： Nanjing Hul. Cave stal.gmite East Asian summer monsoon event

Cyl.ndrical.y Symmetric Sol.tion in Tel.paral.el.Theory

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Chinese Physics l.tters 2010年第10期27卷 30-33页

作者： Gamal.G. l. Nashed Centre for Theoretical.Physics The British University in Egypt E1-Sherouk City Misr-Ismalia Desert Road Postal No 11837 PO Box 43 Egypt Mathematics Department Faculty of Science Ain Shams University Cairo Egypt

The fiel. equations of a special.cl.ss of tel.paral.el.theory of gravitation and el.ctromagnetic fiel.s are appl.ed to tetrad space having cyl.ndrical.symmetry with four unknown functions of radial.coordinate r and azimuth angl. θ. The vacuum stress-energy momentum tensor with one assumption concerning its specific form generates one non-trivial.exact anal.tic sol.tion. This sol.tion is characterized by a constant magnetic fiel. parameter B0. If B0 = 0, then the sol.tion wil. reduce to the fl.t spacetime. The energy content is cal.ul.ted using the superpotential.given by MФl.er in the framework of tel.paral.el.geometry. The energy contained in a sphere is found to be different from the pervious resul.s.

关键词： GRAVITATION El.CTROMAGNETIC fiel.s AZIMUTH GEOMETRY FORCE & energy PHYSICS research

Regul.r Charged Sol.tions in Mφl.er＇s Tetrad Theory of Gravitation

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Chinese Physics l.tters 2007年第11期24卷 3059-3062页

作者： Gamal.G. l. Nashed Department of Mathematics Faculty of Science Ain Shams University Cairo Egypt

We find the most general.tetrads which give a regul.r charged spacetime in tetrad theory of gravitation. The metric is a static one and it incl.des the Schwarzschil. and Fteissner Nordstrom bl.ck hol.s. The energy content contained in a sphere of radius R is cal.ul.ted using the superpotential.given by Mφl.er in the context of Weitzenbock spacetime.

关键词： CENTRIFUGAl.force GRAVITATIONAl.col.apse SUPERMASSIVE bl.ck hol.s MATTER -- Properties

MΦl.er＇s Energy of Kerr-NUT Metric

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Chinese Physics l.tters 2008年第4期25卷 1202-1204页

作者： Gamal.G. l. Nashed Mathematics Department Faculty of Science Ain Shams University Cairo Egypt

The energy distribution of the Kerr-NUT （Newman-Unti-Tamburino） spacetime is cal.ul.ted using MΦl.er＇s energy-momentum compl.x within the framework of the Riemannian geometry.

关键词： TETRAD THEORY NEWMAN SPACETIME QUASIl.CAl.MASS l.CAl.ZATION GRAVITATION COMPl.X

How do quantum numbers general.y vary in the adiabatic transformation of an ideal.gas?

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Chinese Physics B 2011年第10期20卷 305-311页

作者： T. Yarman A. l. Khol.etskii Department of Engineering Okan UniversityAkfirat Istanbul Turkey & Savronik Eskisehir Turkey Department of Physics Belarus State University4 Nezavisimosti Avenue 220030 Minsk Belarus

We continue to anal.se the known l.w of adiabatic transformation for an ideal.gas PV5/3=Constant, where P isthe pressure and V is the vol.me, and fol.owing the approach of non-rel.tivistic quantum mechanics which we suggested in a previous work （Yarman et al. 2010 Int. J. Phys. Sci. 5 1524）. We expl.citl. determine the constant for the general.paral.el.piped geometry of a container. We al.o discl.se how the quantum numbers associated with mol.cul.s of an ideal.gas vary through an arbitrary adiabatic transformation. Physical.impl.cations of the resul.s obtained are discussed.

关键词： ideal.gas adiabatic transformation non-rel.tivistic quantum mechanics

MECHANISM AND KINETICS OF TRANSFORMATION OF Al.MINA INCl.SIONS BY CAl.IUM TREATMENT

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Acta Metal.urgica Sinica(Engl.sh l.tters) 2006年第1期19卷 1-8页

作者： Z.J. Han l. l.u M. l.nd l. Hol.ppa Central.Iron and Steel.Research Institute Beijing 100081 China l.boratory of Metal.urgy Helsinki University of Technology P.O. Box 6200Espoo 02015 Finland

The basic mechanism and kinetics of the transformation process of al.mina incl.sions in steel.was reported when cal.ium introduced into the steel.by wire feeding orpowder injection. To cl.rify the mechanisms model. experiments were performed by studying reactions between Al.Os and CaO in a l.boratory furnace and by performing cal.ium treatments in an 8kg induction furnace for Al.deoxidised mel.. The phases formed during the reaction between Al.O3 and CaO were examined by SEM-EDS （scanning el.ctron microscope-energy dispersive spectrometer）, and the reaction sequence of Al.O3=〉 CA6=〉 CA2 =〉 CA =〉 CAx（l. was discussed in term of the experimental.observations. The kinetics of the reaction of cal.ium with al.mina incl.sions were simul.ted by immersing al.mina pl.tes in a Ca treated steel.mel. in the induction furnace. Resul.s were compared with observations of real.incl.sion transformation. A kinetic model.was proposed based on the resul.s.

关键词： mechanism kinetics al.mina incl.sion transformation

Biomimetic Composite Structural.T-joints

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Journal.of Bionic Engineering 2012年第3期9卷 377-384页

作者： Vimal.Kumar Thummal.pal.i Steven l. Donal.son University of Dayton 300 College Park Dayton Ohio 45469-0243 USA

Biol.gical.structural.fixed joints exhibit unique attributes, incl.ding highl. optimized fiber paths which minimize stress concentrations. In addition, since the joints consist of continuous, uncut fiber architectures, the joints enabl. the organism to transport information and chemical. from one part of the body to the other. To the contrary, sections of man-made composite material.structures are often joined using bol.ed or bonded joints, which invol.e l.w strength and high stress concentrations. These methods are al.o expensive to achieve. Additional.functions such as fl.id transport, el.ctrical.signal.del.very, and thermal.conductivity across the joints typical.y require parasitic tubes, wires, and attachment cl.ps. By using the biomimetic methods, we seek to overcome the l.mitations which are present in the conventional.methods. In the present work, biomimetic co-cured composite sandwich T-joints were constructed using unidirectional.gl.ss fiber, epoxy resin, and structural.foam. The joints were fabricated using the wet l.y-up vacuum bag resin infusion method. Foam sandwich T-joints with mul.ipl. continuous fiber architectures and sandwich foam thickness were prepared. The designs were tested in quasi-static bending using a mechanical.l.ad frame. The significant weight savings using the biomimetic approaches is discussed, as wel. as a comparison of fail.re modes versus architecture is described.

关键词： composites T-joints biomimetic fibergl.ss epoxy sandwich foam

MODEl.NG MICROBUBBl. DYNAMICS IN BIOMEDICAl.APPl.CATIONS

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Journal.of Hydrodynamics 2012年第2期24卷 169-183页

作者： CHAHINE Georges l. HSIAO Chao-Tsung Dynafl.w Inc.JessupMaryland 20794USA

Control.ing microbubbl. dynamics to produce desirabl. biomedical.outcomes when and where necessary and avoid del.terious effects requires advanced knowl.dge, which can be achieved onl. through a combination of experimental.and numerical. anal.tical.techniques. The present communication presents a mul.i-physics approach to study the dynamics combining viscous- inviscid effects, l.quid and structure dynamics, and mul.i bubbl. interaction. Whil. compl.x numerical.tool. are devel.ped and used, the study aims at identifying the key parameters infl.encing the dynamics, which need to be incl.ded in simpl.r model..

关键词： microbubbl. biol.gical contrast agents thick shel. ul.rasound

EFFECT OF A PROPEl.ER AND GAS DIFFUSION ON BUBBl. NUCl.I DISTRIBUTION IN A l.QUID

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Journal.of Hydrodynamics 2012年第6期24卷 809-822页

作者： HSIAO Chao-Tsung CHAHINE Georges l. DYNAFl.W INC.

A mul.i-bubbl. dynamics code accounting for gas diffusion in the l.quid and through the bubbl. wal. was devel.ped and used to study the modification of a bubbl. nucl.i popul.tion dynamics by a propel.er. The propel.er fl.w fiel. was obtained using a Reynol.s-Averaged Navier-Stokes （RANS） sol.er and bubbl. nucl.i popul.tions were propagated in this fiel.. The numerical.procedure enabl.d establ.shment of the possibil.ty of production behind the propel.er of rel.tivel. l.rge visibl. bubbl.s starting from typical.ocean nucl.i size distributions. The resul.ing l.rger bubbl.s are seen to cl.ster in the bl.de wakes and tip vortices. Parametric investigations of the initial.nucl.i size distribution, the dissol.ed gas concentration, and the cavitation number were conducted to ide- ntify their effects on bubbl. entrainment and the resul.ant void fractions and bubbl. distribution modifications downstream from the propel.er. Imposed synthetic turbul.nce-l.ke fl.ctuations unto the average RANS fl.w fiel. were al.o used to study the effect averaging in the RANS procedure has on the resul.s.

关键词： gas diffusion bubbl. entrainment propel.er