Navegação Ciências Exatas e da Terra por Título

Resultados 2927-2946 de 5955

    • Magnetic susceptibility of fe/cu multilayers : ferromagnetic, antiferromagnetic, and spin-glass phases 

      Oliveira, A.J.A. de; Ortiz, Wilson Aires; Mosca Junior, Dante Homero; Mattoso Filho, Ney Pereira; Schreiner, Wido Herwig; Teixeira, Sergio Ribeiro (1998) [Artigo de periódico]
      In this work we present low-field magnetic measurements on multilayers of Fe 1.5 nm and Cu 1.5 nm layers, repeated 10 times, grown on Si~111! and Fe 5 nm/CaF2 40 nm/Si(111), substrates. Magnetic characteristics of a ...

    • Magnetic white dwarf stars in the Sloan Digital Sky Survey 

      Kepler, Souza Oliveira; Pelisoli, Ingrid Domingos; Jordan, Stefan; Kleinman, Scot James; Koester, Detlev; Kulebi, Baybars; Antonio, Viviane Peçanha; Castanheira, Bárbara Garcia; Nitta, Atsuko; Costa, Jose Eduardo da Silveira; Winget, Donald Earl; Kanaan Neto, Antonio Nemer; Fraga, Luciano (2013) [Artigo de periódico]
      To obtain better statistics on the occurrence of magnetism among white dwarfs, we searched the spectra of the hydrogen atmosphere white dwarf stars (DAs) in the Data Release 7 of the Sloan Digital Sky Survey (SDSS) for ...

    • Magnetism and quantum phase transitions in spin-1/2 attractive fermions with polarization 

      He, Jingsong; Foerster, Angela; Guan, Xi-Wen; Batchelor, Murray T. (2009) [Artigo de periódico]
      An extensive investigation is given for magnetic properties and phase transitions in one-dimensional (1D) Bethe ansatz integrable spin-1/2 attractive fermions with polarization by means of the dressed energy formalism. An ...

    • Magnetism in dilute magnetic oxide thin films based on SnO/sub 2/ 

      Fitzgerald, C.B.; Venkatesan, M.; Dorneles, Lucio Strazzabosco; Gunning, R.; Stamenov, Plamen; Coey, John Michael Douglas; Stampe, P.A.; Kennedy, R.J.; Moreira, Eduardo Ceretta; Sias, Uilson Schwantz (2006) [Artigo de periódico]
      Thin films of SnO2 prepared by pulsed-laser deposition on R-cut sapphire substrates exhibit ferromagnetic properties at room temperature when they are doped with Cr, Mn, Fe, Co, or Ni, but not with other 3d cations. ...

    • Magnetism, magnetoresistance, and Shubnikov-de Haas oscillations in Na-implanted highly oriented pyrolitic graphite 

      Pires, Rafael Fernando; Pureur Neto, Paulo; Behar, Moni; Pimentel Junior, Jorge Luiz; Schaf, Jacob; Kopelevich, Y. (2012) [Artigo de periódico]
      We report on magnetization, magnetoresistance, and Shubnikov-de Haas oscillations experiments in Na-implanted samples of highly oriented pyrolitic graphite (HOPG). Different ion fluences were applied so that samples with ...

    • Magnetization dynamics as derived from magneto impedance measurements 

      Carara, Marcos Andre; Baibich, Mario Norberto; Sommer, Rubem Luis (2000) [Artigo de periódico]
      In this work, the magnetization dynamics of soft magnetic materials is studied with the aid of transverse differential permeability μ(Iac , f ,Hdc) spectra. Contributions to the magnetization processes from domain wall ...

    • Magnetization dynamics in nanostructures with weak/strong anisotropy 

      Andrade, Antonio Marcos Helgueira de; Corrêa, Marcio Assolin; Viegas, Alexandre da Cas; Bohn, Felipe; Sommer, Rubem Luis (2014) [Artigo de periódico]
      We investigate the high-frequency response of magnetization dynamics through magnetoimpedance (MI) effect in Permalloy-based multilayered thin films produced with two different non-magnetic metallic spacers: Cu and Ag. Due ...

    • Magnetization process and magnetoimpedance in (110)[001]FeSi/Sub 3% 

      Carara, Marcos Andre; Gundel, Andre; Baibich, Mario Norberto; Sommer, Rubem Luis (1998) [Artigo de periódico]
      The present article investigates the relation between magnetoimpedance (MI) and the evolution of the magnetic domain structure along the magnetization curves of commercial FeSi3% sheets cut at different angles with respect ...

    • Magnetoconductivity of a disordered electron system with n orbitals persite 

      Magalhaes, Sergio Garcia; Theumann, Alba Graciela Rivas de (1994) [Artigo de periódico]
      In the absence of a magnetic field, two formally equivalent expressions for the conductivity contribute different sets of Feynman diagrams, due to cancellations. We use this result to calculate the magnetoconductivity of ...

    • Magnetoelectric effect and phase transitions in CuO in external magnetic fields 

      Wang, Zhaosheng; Qureshi, Navid; Yasin, Shadi; Mukhin, Alexander; Ressouche, Eric; Zherlitsyn, Sergei; Skourski, Yurii; Geshev, Julian Penkov; Ivanov, Vsevolod; Gospodinov, Marin; Skumryev, Vassil (2016) [Artigo de periódico]
      Apart from being so far the only known binary multiferroic compound, CuO has a much higher transition temperature into the multiferroic state, 230 K, than any other known material in which the electric polarization is ...

    • Magnetometria in-situ para caracterização de materiais eletrodepositados 

      Franco, Vinícius Cappellano de; Schmidt, Joao Edgar (2019) [Artigo de periódico]
      We have recently made studies of electrodeposits of Co onto graphene attached to different substrates, successfully performed via in-situ magnetization measurements. The magnetic analysis of deposits as a function of time ...

    • Magnetoresistance in rf-sputtered(nife/cu/co/cu) spin-valve multilayers 

      Lottis, Daniel Kurt; Fert, Albert R.; Morel, Robert; Pereira, Luis Gustavo; Jacquet, J.C.; Galtier, P.; Coutellier, J.M.; Valet, Tierry (1993) [Artigo de periódico]
      A study of the vtiation of the magnetoresistancein (Ni80Fe20/Cu/Co/Cu) multilayers with the thicknesses tNiFe, tcO, and &;cu of each type of component layer has been performed. The magnetoresistance (MR), which at 4 .2 K ...

    • Magnetoresistance of doped silicon 

      Silva, Antonio Ferreira da; Levine, Alexandre; Momtaz, Zahra Sadre; Boudinov, Henri Ivanov; Sernelius, Bo E. (2015) [Artigo de periódico]
      We have performed longitudinal magnetoresistance measurements on heavily n-doped silicon for donor concentrations exceeding the critical value for the metal-nonmetal transition. The results are compared to those from a ...

    • Magnetoresistance of pd-fe and pd-ni-fe alloys 

      Hsu, Y.; Schmidt, Joao Edgar; Gupta, M.; Jen, S.; Berger, Luc (1983) [Artigo de periódico]
      The electrical resistivity ofPd-Fe alloys has been measured in magnetic fields parallel and perpendicular to the current, for a wide range of alloy compositions. The influence of atomic ordering on the magnetoresistance ...

    • Magnetosonic waves in a quantum plasma with arbitrary electron degeneracy 

      Haas, Fernando; Mahmood, Shahzad (2018) [Artigo de periódico]
      Using a two-species quantum hydrodynamic model, we derive the quantum counterpart of magnetosonic waves, in a plasma with arbitrary degree of degeneracy and taking into account quantum diffraction effects due to the ...

    • Magnetostriction in ar/sup +/ implanted and annealed co/pd multilayers 

      Viegas, Alexandre da Cas; Schelp, Luiz Fernando; Schmidt, Joao Edgar (1995) [Artigo de periódico]
      Magnetostriction curves with (111) textured polycrystalline Co/Pd multilayers, as deposited or submitted to ArS ion implantation or thermal annealing, are presented and discussed. Both treatments, while promoting intermixing ...

    • Magnetostriction of pd-fe alloys 

      Schmidt, Joao Edgar; Berger, Luc (1994) [Artigo de periódico]
      The linear magnetostriction λs of polycrystalline Pd1-xFex alloys has been measured as a function of alloy composition, at temperatures of 300,77, and 4.2 K. The effect on λs of atomic ordering of Pd3Fe and PdFe type has ...

    • Magnetotransport properties in the magnetic phase of BaFe2−xTxAs2 (T = Co,Ni) : a magnetic excitations approach 

      Peña Pacheco, Jully Paola; Piva, M. M.; Rosa, P. F. S.; Pagliuso, P. G.; Adriano, C.; Grant, Ted W.; Fisk, Zachary; Baggio-Saitovitch, E.; Pureur Neto, Paulo (2018) [Artigo de periódico]
      Because of their complex Fermi surfaces, the identification of the physical phenomena contributing to electronic scattering in the Fe-based superconductors is a difficult task. Here, we report on the electrical resistivity, ...

    • Making decisions and motor actions with technical biomechanical classifications in male judo weight categories 

      Sobarzo Soto, Dany Alexis; Aedo-Muñoz, Esteban; Brito, Ciro José; Camey, Suzi Alves; Miarka, Bianca (2020) [Artigo de periódico]
      The aim of the study was to compare motor action variables of judo combat phases and technical biomechanical assessment of the seven weight categories. The sample was composed of 638 bouts (176 of extra lightweight <66 kg, ...

    • Making java work for microcontroller applications 

      Ito, Sergio Akira; Carro, Luigi; Jacobi, Ricardo Pezzuol (2001) [Artigo de periódico]