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Research paper thumbnail of Magnetic properties of Fe3O4 and CoFe2O4 nanoparticles functionalized with L-aspartic acid

The study of magnetic nanoparticles has attracted great attention of researchers in nanoscience a... more The study of magnetic nanoparticles has attracted great attention of researchers in nanoscience and nanotechnology. It has been recognized that these systems can be applied in several fields, including catalysis, biomedicine, magnetic resonance imaging, data storage media, and drug delivery among others. We have produced Fe3O4 and CoFe2O4 magnetic nanoparticles (MNP) functionalized with amino acid (L-aspartic acid). The MNP were obtained by the thermal decomposition method using ionic liquid (IL) as solvent. Recycles reactions were conducted at least six times using the IL. X-ray powder diffraction measurements showed that all Bragg reflections belong to either MNP crystal phase or the matrix phase which is the L-aspartic acid. The broad peaks from nanoparticles correspond to spinel cubic symmetry and the amino acid matrix shows intense and narrow peaks belonging to the monoclinic P21a space group. The nanoparticles size and its distribution have been determined by transmission elec...

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Research paper thumbnail of Microfabricated inductors for 20 MHz Dc-Dc converters

2008 Twenty-Third Annual IEEE Applied Power Electronics Conference and Exposition, 2008

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Research paper thumbnail of High current inductor design for MHz switching

2008 IEEE Power Electronics Specialists Conference, 2008

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Research paper thumbnail of Core Materials for High Frequency VRM Inductors

2007 IEEE Power Electronics Specialists Conference, 2007

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Research paper thumbnail of Electrodeposited anisotropic NiFe 45/55 thin films for high-frequency micro-inductor applications

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Research paper thumbnail of High-frequency permeability of electroplated CoNiFe and CoNiFe–C alloys

Journal of Magnetism and Magnetic Materials, 2008

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Research paper thumbnail of Spin dynamics of polycrystalline Ni films on Si substrate

Journal of Magnetism and Magnetic Materials, 2010

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Research paper thumbnail of Magnetic properties and underlayer thickness in SmCo/Cr films

Journal of Applied Physics, 2000

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Research paper thumbnail of Dependence of magnetic properties on micro- to nanostructure of CoNiFe films

Journal of Applied Physics, 2008

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Research paper thumbnail of Magnetic properties of nickel nanowires: Effect of deposition temperature

Journal of Applied Physics, 2009

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Research paper thumbnail of Preisach analysis of sputtered SmCo thick films

Journal of Applied Physics, 2013

ABSTRACT Here, we present an implementation of the moving Preisach model to describe the magnetic... more ABSTRACT Here, we present an implementation of the moving Preisach model to describe the magnetic behaviour of Sm-Co films. We use two independent Preisach distributions to separate the magnetization into reversible and irreversible components. The numerical simulation works very well for a system where two magnetic phases are weakly or negligibility coupled. We tested our implementation on nanocrystalline Sm-Co films prepared by sputtering and having composition around Sm25Co75. We found that the Sm25Co75 film has a soft and hard phase and quantified their contributions to the total magnetization. Using the moving Preisach model, we characterized the properties of the hard phase, which has a coercivity of 1.26 T and contribution of 74% to the total magnetization. The soft magnetic phase contributes 26% to the total magnetization and has a coercivity of 0.056 T.

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Research paper thumbnail of Electrodeposited CoNiFeP Soft-Magnetic Films for High-Frequency Applications

IEEE Transactions on Magnetics, 2000

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Research paper thumbnail of Thin-Film-Integrated Power Inductor on Si and Its Performance in an 8-MHz Buck Converter

IEEE Transactions on Magnetics, 2000

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Research paper thumbnail of Electroless thin film CoNiFe–B alloys for integrated magnetics on Si

Electrochimica Acta, 2009

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Research paper thumbnail of Coaxial metal and magnetic alloy nanotubes in polycarbonate templates by electroless deposition

Electrochemistry Communications, 2008

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Research paper thumbnail of Magnetic properties of Ni nanoparticles on microporous silica spheres

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Research paper thumbnail of Magnetic properties of Fe3O4 and CoFe2O4 nanoparticles functionalized with L-aspartic acid

The study of magnetic nanoparticles has attracted great attention of researchers in nanoscience a... more The study of magnetic nanoparticles has attracted great attention of researchers in nanoscience and nanotechnology. It has been recognized that these systems can be applied in several fields, including catalysis, biomedicine, magnetic resonance imaging, data storage media, and drug delivery among others. We have produced Fe3O4 and CoFe2O4 magnetic nanoparticles (MNP) functionalized with amino acid (L-aspartic acid). The MNP were obtained by the thermal decomposition method using ionic liquid (IL) as solvent. Recycles reactions were conducted at least six times using the IL. X-ray powder diffraction measurements showed that all Bragg reflections belong to either MNP crystal phase or the matrix phase which is the L-aspartic acid. The broad peaks from nanoparticles correspond to spinel cubic symmetry and the amino acid matrix shows intense and narrow peaks belonging to the monoclinic P21a space group. The nanoparticles size and its distribution have been determined by transmission elec...

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Research paper thumbnail of Microfabricated inductors for 20 MHz Dc-Dc converters

2008 Twenty-Third Annual IEEE Applied Power Electronics Conference and Exposition, 2008

Bookmarks Related papers MentionsView impact

Research paper thumbnail of High current inductor design for MHz switching

2008 IEEE Power Electronics Specialists Conference, 2008

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Core Materials for High Frequency VRM Inductors

2007 IEEE Power Electronics Specialists Conference, 2007

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Electrodeposited anisotropic NiFe 45/55 thin films for high-frequency micro-inductor applications

Bookmarks Related papers MentionsView impact

Research paper thumbnail of High-frequency permeability of electroplated CoNiFe and CoNiFe–C alloys

Journal of Magnetism and Magnetic Materials, 2008

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Spin dynamics of polycrystalline Ni films on Si substrate

Journal of Magnetism and Magnetic Materials, 2010

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Magnetic properties and underlayer thickness in SmCo/Cr films

Journal of Applied Physics, 2000

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Dependence of magnetic properties on micro- to nanostructure of CoNiFe films

Journal of Applied Physics, 2008

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Magnetic properties of nickel nanowires: Effect of deposition temperature

Journal of Applied Physics, 2009

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Preisach analysis of sputtered SmCo thick films

Journal of Applied Physics, 2013

ABSTRACT Here, we present an implementation of the moving Preisach model to describe the magnetic... more ABSTRACT Here, we present an implementation of the moving Preisach model to describe the magnetic behaviour of Sm-Co films. We use two independent Preisach distributions to separate the magnetization into reversible and irreversible components. The numerical simulation works very well for a system where two magnetic phases are weakly or negligibility coupled. We tested our implementation on nanocrystalline Sm-Co films prepared by sputtering and having composition around Sm25Co75. We found that the Sm25Co75 film has a soft and hard phase and quantified their contributions to the total magnetization. Using the moving Preisach model, we characterized the properties of the hard phase, which has a coercivity of 1.26 T and contribution of 74% to the total magnetization. The soft magnetic phase contributes 26% to the total magnetization and has a coercivity of 0.056 T.

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Research paper thumbnail of Electrodeposited CoNiFeP Soft-Magnetic Films for High-Frequency Applications

IEEE Transactions on Magnetics, 2000

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Research paper thumbnail of Thin-Film-Integrated Power Inductor on Si and Its Performance in an 8-MHz Buck Converter

IEEE Transactions on Magnetics, 2000

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Electroless thin film CoNiFe–B alloys for integrated magnetics on Si

Electrochimica Acta, 2009

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Coaxial metal and magnetic alloy nanotubes in polycarbonate templates by electroless deposition

Electrochemistry Communications, 2008

Bookmarks Related papers MentionsView impact

Research paper thumbnail of Magnetic properties of Ni nanoparticles on microporous silica spheres

Bookmarks Related papers MentionsView impact

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