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Formation and Surface Structural Features of Crystalline Ceramic Nanocomposite Coatings on Aluminium Using Lithium Sulphate with Silicate Additive

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Acta metallurgica Sinica(English Letters) 2014年第2期27卷 185-197页

作者： m.mubarak Ali v.Raj Department of Chemistry Chikkaiah Naicker College Advanced materials Research Laboratory Department of ChemistryPeriyar University

We have synthesized a series of the ceramic coatings by anodization of aluminium using lithium sulphate and sodium silicate additive. Our experiments show that the present coatings are nanocomposites in nature, consisting of a mixture of nanocrystalline alumina, silica, aluminium silicate and mullite; the formation of alumina was similar to conventional anodizing technology, while the formation of mullite was attributed to an addition of sodium silicate. The microhardness of the coatings progressively increased with the increasing current density up to 0.2 A/cm2, which could mainly be attributed to the decrease of porosity in the interfacial region of the oxides up to the range. From the performance of the coatings against corrosion （Tafel/Nyquist plots）, it was inferred that the coatings fabricated by lithium sulphatesodium silicate bath have enhanced corrosion resistance （Rp = 3.12 kΩ）, as well as better microhardness value than that of the lithium sulphate bath alone （Rp = 660.96 Ω） which confirm the perception that the silica particles included in the anodized alumina matrices randomly. Presence of Al, Si and O indicated that the electrolyte components had been intensively incorporated into the coatings.

关键词： Anodization Nanocomposite Ceramic Lithium sulphate

Influence of FCA Welding Process Parameters on Distortion of 409m Stainless Steel for Rail Coach Building

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Journal of Iron and Steel Research International 2013年第1期20卷 71-78页

作者： m v venkatesan N murugan B m Prasad A manickavasagam Department of mechanical Engineering Coimbatore Institute of TechnologyCoimbatore 641014TNIndia Integral Coach Factory Indian RailwaysChennai 600038TNIndia

The influence of flux cored arc welding （FCAW） process parameters such as welding current, travel speed, voltage and CO2 shielding gas flow rate on bowing distortion of 409m ferritic stainless steel sheets of 2 mm in thickness was discussed. The bowing distortions of the welded plates were measured using a simple device called profile tracer. An experimental regression equation was developed to predict the bowing distortion and with this equation, it is easy to select optimized process parameters to achieve minimum bowing distortion. It is revealed that the FCAW process parameters have significant influence on bead profile and the bowing distortion.

关键词： bowing distortion ferritic stainless steel flux cored arc welding statistical model rail coach distortion measurement

Twofold hidden conformal symmetry of Kerr-Bolt black holes

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Chinese Physics B 2012年第2期21卷 117-122页

作者： m.R.Setare v.Kamali Department of Science Campus of BijarUniversity of Kurdistan BijarIran

Previously we have shown that a four-dimensional Kerr-Bolt black hole in non-extremal and also in extremal cases could be described by a holographic two-dimensional （2D） conformal field theory （CFT） [Ghezelbash A m, Kamali v and Setare m R 2010 Phys. Rev. D 82 124051; Setare m R and Kamali v 2010 JHEP 10 074]. motivated by recent work [Chen C m, Huang Y m, Sun J R, Wu m F and Zou S J 2010 Phys. Rev. D 82 066004], we show that there is another holographic description for these black holes. The first description is called the J-picture, whose construction is based on the black hole angular momentum. The new description is called the Q-picture, whose constructions originate from the nut charge of the black hole. Similar to the previous cases [Ghezelbash A m, Kamali v and Setare m R 2010 Phys. Rev. D 82 124051; Setare m R and Kamali v 2010 JHEP 10 0741, we show that this new picture for a low frequency limit of the wave equation of a massless charged scalar field in the background of a Kerr-Bolt black hole can be written as the Casimir of SL（2, R） symmetry. Our result shows that the entropy of the black hole is reproduced by the Cardy formula. In addition, the absorption cross section is consistent with the finite temperature absorption cross section for a two-dimensional CFT.

关键词： Kerr-Bolt back hole holographic descriptions hidden conformal symmetry Cardy formula

Optimizing the Pulsed Current Gas Tungsten Arc Welding Parameters

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Journal of materials Science & Technology 2006年第6期22卷 821-825页

作者： m.Balasubramanian v.Jayabalan v. Balasubramanian Department of Production Engineering Sathyabama Institute of Science and TechnologyIndia Department of manufacturing Engineering Anna UniversityIndia Department of manufacturing Engineering Annamalai UniversityIndia

The selection of process parameter in the gas tungsten arc （GTA） welding of titanium alloy was presented for obtaining optimum grain size and hardness. Titanium alloy （Ti-6Al-4v） is one of the most important non-ferrous metals which offers great potential application in aerospace, biomedical and chemical industries, because of its low density （4.5 g/cm^3）, excellent corrosion resistance, high strength, attractive fracture behaviour and high melting point （1678℃）. The preferred welding process for titanium alloy is frequent GTA welding due to its comparatively easier applicability and better economy. In the case of single pass （GTA） welding of thinner section of this alloy, the pulsed current has been found beneficial due to its advantages over the conventional continuous current process. many considerations come into the picture and one needs to carefully balance various pulse current parameters to reach an optimum combination. Four factors, five level, central composite, rotatable design matrix were used to optimize the required number of experimental conditions. mathematical models were developed to predict the fusion zone grain size using analysis of variance （ANOvA） and regression analysis. The developed models were optimized using the traditional Hooke and Jeeve＇s algorithm. Experimental results were provided to illustrate the proposed approach.

关键词： Pulsed current Gas tungsten arc welding Titanium alloy Design of experiments ANOvA, Hooke and Jeeve's algorithm Grain size Hardness

Process Parameter Optimization of the Pulsed Current Argon Tungsten Arc Welding of Titanium Alloy

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Journal of materials Science & Technology 2008年第3期24卷 423-426页

作者： m.Balasubramanian v.Jayabalan v.Balasubramanian Department of mechanical Engineering Maamallan Institute of Technology Department of manufacturing-Engineering Anna University Department of manufacturing Engineering Annamalai University

The selection of process parameters for obtaining optimal tensile properties in the pulsed current gas tungsten arc welding is presented. The tensile properties include ultimate tensile strength, yield strength and notch tensile strength. All these characteristics are considered together in the selection of process parameters by modified taguchi method to analyse the effect of each welding process parameter on tensile properties. Experimental results are furnished to illustrate the approach.

关键词： Pulsing current modified taguchi method Tensile properties

Deuteron inelastic scattering on ^(6)Li and ^(7)Li nuclei within the three-body cluster model

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Chinese Physics C 2021年第1期45卷 286-296页

作者： m.v.Egorov v.I.Postnikov Federal State Unitary Enterprise"Russian Federal Nuclear"Center'Academician E.I.Zababakhin All-Russian Research Institute of Technical Physics SnezhinskChelyabinsk Region.Russia and Physics FacultyTomsk State UniversityLenina ave.36Tomsk 634050Russia National Research Nuclear University mEPhI MoscowRussia

The problem of the deuteron interaction with lithium nuclei,treated as a system of two coupled pointlike clusters,is formulated to calculate the cross sections of the d+Li *** d+Li reaction mechanism is described using the Faddeev theory for the three-body problem of deuteron-nucleus *** theory is slightly extended for calculation of the stripping processes ^6Li(d,p)^7Li,^7Li(d,p)^8 ,^6Li(d,n)^7 Be,and ^7Li(d,n)^8 Be,as well as fragmentation reactions yielding tritium,a-particles,and continuous neutrons and protons in the initial deuteron kineticenergy region Ed=0.5-20 *** phase shifts found for d+^6Li and d+^7Li elastic scattering,as part of the simple optic model with a complex central potential,were used to find the cross sections for the 6^Li(d,ym)^8 and ^7Li(d,yE1)^9 Be radiation *** three-body dynamics role is also summarized to demonstrate its significant influence within the d+^7Li system.

关键词： deuteron-Li Faddeev equation inelastic scattering cluster model

Bending sensor based on flexible spin valve

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Chinese Physics B 2023年第5期32卷 655-661页

作者： L I Naumova R S Zavornitsyn m A milyaev N G Bebenin A Y Pavlova m v makarova I K maksimova v v Proglyado A A Zakharov v v Ustinov m.N.miheev Institute of metal Physics Ural BranchRussian Academy of SciencesS.Kovalevskoi Street 18Ekaterinburg 620990Russia

Flexible spin valves were prepared by magnetron sputtering on polyimide substrates. The buffer layer that reduces significantly the effect of the polymer substrate on the spin valve microstructure and magnetoresistive properties was revealed. Bending deformation was applied to the microobjects based on the flexible spin valves in parallel to anisotropy axes. It was revealed that during the bend the magnetoresistance changes due to the joint impact of both the change of the magnetic field projection on the film plane and the change of the magnetic properties of the ferromagnetic layers. The obtained dependences have been used in construction of bending sensor, in which the flexible spin valve microstripes were united into the Wheatstone bridge.

关键词： spin valve polymer substrate magnetostriction magnetic anisotropy

Chemoselective Dehydrogenation of 3-[2-(3,4-Dihydro-1-naphthalenyl)ethyl]imidazolidine-2,4-diones: a New and Convenient Synthesis of 13,16-Diazaequilenin analogs

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Chinese Journal of Chemistry 2004年第10期22卷 1196-1199页

作者： PARIHAR J.A RAmANA m.m.v Department of Chemistry University of Mumbai Santacruz (E) Mumbai-400098 IndiaDepartment of Chemistry University of Mumbai Santacruz (E) Mumbai-400098 India

The synthesis of the title compounds starting with the chemoselective dehydrogenation of 3-[2-(3,4-dihydro-1-naphthalenyl)ethyl]imidazolidine-2,4-diones has been described.

关键词： chemoselective dehydrogenation imide reduction intramolecular cyclization 13,16-diazasteroid

Takagi-Sugeno Fuzzy Regulator Design for Nonlinear and Unstable Systems Using Negative Absolute Eigenvalue Approach

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IEEE/CAA Journal of Automatica Sinica 2020年第2期7卷 482-493页

作者： Ravi v.Gandhi Dipak m.Adhyaru Department of Electrical Engineering Indian Institute of Technology(IIT)GandhinagarGandhinagar 382355India Department of Instrumentation&Control Engineering Institute of TechnologyNirma UniversityAhmedabad-382481India

This paper introduces a Takagi-Sugeno(T-S)fuzzy regulator design using the negative absolute eigenvalue(NAE)approach for a class of nonlinear and unstable *** open-loop system is initially embodied by the traditional T-S fuzzy model and then,all closed-loop subsystems are combined using the proposed max-min operator in place of traditional weighted average operator from the controller side to lessen the coupling virtually and simplify the proposed regulator *** each virtually decoupled closed-loop subsystem,the composite regulators(i.e.,primary and secondary regulators)are designed by the NAE approach based on the enhanced eigenvalue *** Lyapunov function is utilized to guarantee the asymptotic stability of the overall T-S fuzzy control *** most popular and widely used nonlinear and unstable systems like the electromagnetic levitation system(EmLS)and the inverted cart pendulum(ICP)are simulated for the wide range of the initial conditions and the enormous variation in the *** transient and steady-state performance of the considered systems using the proposed design are analyzed in terms of the decay rate,settling time and integral errors as IAE,ISE,ITAE,and ITSE to validate the effectiveness of the proposed approach compared to the most popular and traditional parallel distributed compensation(PDC)approach.

关键词： Eigenvalue approach nonlinear and unstable systems stability analysis Takagi-Sugeno(T-S)fuzzy regulator