27 research outputs found
Plasma-chemical synthesis of Fe3O4 nanoparticles for doping of high-temperature superconductors
Abstract Ferrite nanoparticles (Fe3O4) have been produced
by the direct low-pressure plasma-chemical synthesis.
X-ray diffraction (XRD), high-resolution transmission
electron microscopy (HRTEM), vibration magnetometry
(VSM), and Mössbauer spectroscopy (NGR) were used
for measurements, showing that the produced nanoparticles
have an average size of 9.4 nm, a crystalline phase of magnetite,
possess a property of superparamagnetism at room
temperature, and have a blocking temperature of 89 K. The
peculiarities of nanoparticle behavior in the magnetic field,
related to a large specific surface area, are discussed
Plasma-chemical synthesis of Fe3O4 nanoparticles for doping of high-temperature superconductors
Abstract Ferrite nanoparticles (Fe3O4) have been produced
by the direct low-pressure plasma-chemical synthesis.
X-ray diffraction (XRD), high-resolution transmission
electron microscopy (HRTEM), vibration magnetometry
(VSM), and Mössbauer spectroscopy (NGR) were used
for measurements, showing that the produced nanoparticles
have an average size of 9.4 nm, a crystalline phase of magnetite,
possess a property of superparamagnetism at room
temperature, and have a blocking temperature of 89 K. The
peculiarities of nanoparticle behavior in the magnetic field,
related to a large specific surface area, are discussed
The morphological and structural features of ferrite compositions (1-x) MeFe2O4 xP2O5 prepared by plasma spraying
Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.Structural features of spinel ferrites formed by rapid quenched from the liquid state, has been studied. It
was found that higher quenching rates cause sequential disorder of the spinel structure. Process starts
with statistically uniform redistribution of cations at lattice points, then collapse of the anionic frame
leads to the topological disorder. This process results in formation of the thermodynamically unstable
cluster state and heating of these hardened ferrites leads to a stepwise release of energy. Therefore the
described process improves activity of ferrite powders in solid-phase and catalytic reaction
The morphological and structural features of ferrite compositions (1-x) MeFe2O4 xP2O5 prepared by plasma spraying
Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.Structural features of spinel ferrites formed by rapid quenched from the liquid state, has been studied. It
was found that higher quenching rates cause sequential disorder of the spinel structure. Process starts
with statistically uniform redistribution of cations at lattice points, then collapse of the anionic frame
leads to the topological disorder. This process results in formation of the thermodynamically unstable
cluster state and heating of these hardened ferrites leads to a stepwise release of energy. Therefore the
described process improves activity of ferrite powders in solid-phase and catalytic reaction