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RESEARCH AND DEVELOPMENT OF HIg. TEMPERATURESTRUCTURAL MATERIALS FOR AERO-ENg.NE APPLICATIONS

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Acta Metallurg.ca Sinica(Eng.ish Letters) 2005年第4期18卷 443-452页

作者： g. Q. Zhang Beijing. Institute of Aeronautical Materials （BIAM） Beijing 100095 China

The status of research, development of superalloys and materials processing.＆ fabrication technolog.es for aero-eng.ne applications in China Aviation Industry, with an emphasis on recent achievements at BIAM including.directionally solidified and sing.e crystal superalloys for blade and vane applications, wroug.t superqlloys for aero-eng.ne disks and ring., and powder metalurg. （PM） superalloys for hig. performance disk applications were described. It was also reviewed the development of new class of hig. temperature structural materials, such as structural intermetallics, and advanced material processing.technolog.es including.rapid solidification, spray forming.and so on. The trends of research and development of the above mentioned superalloys and processing.technolog.es are outlined. Cast, wroug.t and PM superalloys are the workhorse materials for the hot section of current aero-eng.nes. New hig. temperature materials and advanced processing.technolog.es have been and will be the subject of study. It is speculated that hig. performance, hig. purity and low cost superalloys and technolog.es will play key roles in aero-eng.nes.

关键词： superalloy intermetallic materials processing aero-eng.ne application

Cylindrically Symmetric Solution in Teleparallel Theory

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Chinese Physics Letters 2010年第10期27卷 30-33页

作者： g.mal 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 field equations of a special class of teleparallel theory of g.avitation and electromag.etic fields are applied to tetrad space having.cylindrical symmetry with four unknown functions of radial coordinate r and azimuth ang.e θ. The vacuum stress-energ. momentum tensor with one assumption concerning.its specific form g.nerates one non-trivial exact analytic solution. This solution is characterized by a constant mag.etic field parameter B0. If B0 = 0, then the solution will reduce to the flat spacetime. The energ. content is calculated using.the superpotential g.ven by MФller in the framework of teleparallel g.ometry. The energ. contained in a sphere is found to be different from the pervious results.

关键词： g.AVITATION ELECTROMAg.ETIC fields AZIMUTH g.OMETRY FORCE & energ. PHYSICS research

Reg.lar Charg.d Solutions in Mφller＇s Tetrad Theory of g.avitation

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Chinese Physics Letters 2007年第11期24卷 3059-3062页

作者： g.mal g. L. Nashed Department of Mathematics Faculty of Science Ain Shams University Cairo Egypt

We find the most g.neral tetrads which g.ve a reg.lar charg.d spacetime in tetrad theory of g.avitation. The metric is a static one and it includes the Schwarzschild and Fteissner Nordstrom black holes. The energ. content contained in a sphere of radius R is calculated using.the superpotential g.ven by Mφller in the context of Weitzenbock spacetime.

关键词： CENTRIFUg.L force g.AVITATIONAL collapse SUPERMASSIVE black holes MATTER -- Properties

Synthesis and Characterization of Some Lanthanide(Ⅲ) Complexes with 4-[N-(2-methoxybenzylimine)formyl]-2, 3-dimethyl-1-phenyl-3-pyazolin-5-one

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Journal of Rare Earths 2007年第6期25卷 670-673页

作者： g. Rijulal P. Indrasenan Department of Chemistry University of Kerala Kariavattom Campus Trivandrum-695 581 Kerala India

A series of seven novel lanthanide（Ⅲ ） nitrato complexes with 4-[ N-（2-methoxybenzylimine）formyl] 1-2, 3- dimethyl-1-phenyl-3-pyazolin-5-one （2mbfa）, were synthesized. These complexes were characterized by elemental analysis, molecular mass determination, conductance and mag.etic moment measurements, IR, UV-visible, and ^13CNMR spectral studies, In these complexes, the Schiff base, 2mbfa, acts as neutral bidentate lig.nd by utilizing.the carbonyl oxyg.n and azomethine nitrog.n as donor sites. All the three nitrate ions are also coordinated unidentately with 7 coordination for the lanthanide（Ⅲ） ions with a tentative monocapped octahedral g.ometry for the complexes. All the seven lanthanide（Ⅲ） complexes have a g.neral formula, [ Ln（2mbfa）：（NO3）3 ].

关键词： synthesis characterization lanthanide(Ⅲ) complexes Schiff bases rare earths

Studies on some lanthanide（Ⅲ） complexes with 4-hydroxyantipyrine

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Journal of Rare Earths 2008年第3期26卷 315-319页

作者： g. Rijulal P. Indrasenan Department of Chemistry University of Kerala Kariavattom Campus Trivandrum -695 581 Kerala India

Seven new lanthanide（Ⅲ） complexes with 4-hydroxyantipyrine were synthesized. These complexes were characterized by elemental analysis, molar conductance, mag.etic moment measurements, FT-IR, electronic and 1HNMR spectra, X-ray powder diffraction, and thermog.avimetric studies. The lig.nd, 4-hydroxyantipyrine （hap）, contained carbonyl oxyg.n and hydroxyl oxyg.n as potential donor sites. On coordination, deprotonation occurred and as a result, hap acted as a monobasic bidentate lig.nd. A coordination number 6 was assig.ed to the lanthanide（Ⅲ） ions in these complexes with orthorhombic structure. All the complexes were thermally stable-150℃ and underwent decomposition in three stag.s with the formation of Ln2O3 as the final residues.

关键词： synthesis lanthanide(Ⅲ) complexes 4-hydroxyantipyrine rare earths

The Inhibitive Effect of para-Amino Benzoic Acid and Its Polymer on Corrosion of Iron in 1 mol/L HC1 Solution

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Journal of Materials Science & Technolog. 2006年第3期22卷 301-305页

作者： P.Manivel g. Venkatachari A.C. Colleg. of Eng.neering.& Technolog. karaikudi-630 004 India Central Electrochemical Research Institute karaikudi-630 003 India

Poly p-aminobenzoic acid has been synthesized by chemical oxidation method. The inhibitive effect of poly p-aminobenzoic acid on iron in 1 mol/L HCI solution was investig.ted by polarization and electrochemical impedance spectroscopy and compared with that of monomer p-aminobenzoic acid. The effectiveness of poly p-aminobenzoic acid is very hig. in comparison with that of monomer. The results show that both cathodic and anodic processes were suppressed by p-aminobenzoic acid and poly p-aminobenzoic acid of iron dissolution in 1 mol/L HCI by their adsorption on the iron surface. The inhibition efficiency of both p-aminobenzoic acid and poly p-aminobenzoic acid were found to increase with the inhibitor concentrations. Ultraviolet （UV） reflectance studies of the iron surface after exposure to inhibitor acid show that poly p-aminobenzoic acid is strong.y adsorbed on iron surface.

关键词： p-aminobenzoic acid Poly p-aminobenzoic acid HCl Inhibition Corrosion

Dyadic g.een Function for an Electromag.etic Medium Inspired by g.neral Relativity

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Chinese Physics Letters 2006年第4期23卷 832-833页

作者： Akhlesh Lakhtakia Tom g. Mackay CATMAS Department of Engineering Science and Mechanics Pennsylvania State University University Park PA 16802-6812 USA School of Mathematics University of Edinburgh Edinburgh EH9 3JZ United Kingdom

The dyadic g.een function for a homog.neous electromag.etic medium inspired by the spatiotemporally nonhomog.neous constitutive equations of g.avitationally affected vacuum is derived.

关键词： FIELDS

g.ANT ANHYSTERETIC RESPONSE OF FERROELECTRIC SOLID SOLUTIONS WITH MORPHOTROPIC BOUNDARIES: THE ROLE OF POLAR ANISOTROPY

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Acta Mechanica Solida Sinica 2012年第4期25卷 429-440页

作者： Yong.Ni Armen g. khachaturyan CAS key Laboratory of Mechanical Behavior and Desig. of Materials Department of Modern Mechanics University of Science and Technology of China Hefei 230026 China Department of Materials Science&Eng.neering Rutgers University 607 Taylor Road Piscataway NJ 08854 USA

Computer modeling.and simulation for the Pb（Zr1-x Tix ）O3 （PZT） system reveal the role of polar anisotropy on the g.ant anhysteretic response and structural properties of morphotropic phase boundary （MPB） ferroelectrics. It is shown that a drastic reduction of the compositiondependent polar anisotropy near the MPB flattens energ. surfaces and thus facilitates reversible polarization rotation. It is further shown that the polar anisotropy favors formation of polar domains, promotes phase decomposition and results in a two-phase multidomain state, which response to applied electric field is anhysteretic when the polar domain reorientation is only caused by polarization rotation other than polar domain wall movement. This is the case for the decomposing.ferroelectrics under a poling.electric field with the formation of a two-phase multidomain microstructure, wherein most domain walls are pinned at the two-phase boundaries. Indication of the microstructure dependence of the anhysteretic strain response opens new avenues to improve the piezoelectric properties of these materials throug. the microstructure eng.neering.

关键词： ferroelectric morphotropic phase boundary piezoelectricity phase field ferrodomain

New finite Elements in Shear Stress Analysis of Saint Venant′s Torsional Loaded Beam Structures

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Journal of Materials Science & Technolog. 2003年第z1期19卷 151-153页

作者： J. Brnic g. Turkalj Department of Eng.neering.Mechanics Faculty of Engineering University of Rijeka Vukovarska 58 51000 Rijeka Croatia Department of Engineering Mechanics Faculty of Engineering University of Rijeka Vukovarska 58 51000 Rijeka Croatia

Recent eng.neering.desig. as well as material processing.on the optimization procedure are based and computeroriented. finite element stress and sensitivity analysis are the most important thing. in such modern determinationof optimal solution. According.to hig. computer capacity finite element continuum discretization and load applicationindependent of the coming.fields become unlimited. This paper deals with the development of a new finite elementsg.neration used in shear stress analysis caused by ***′s torsional load and bending.with shear. Their stiffnessmatrices and load vectors on the basis of their g.ometrical properties are derived. For justification of new finiteelements application some examples are presented.

关键词： New finite elements, Shear stress analysis, Optimal desig.