Correlation of crystalline and magnetic structures of barium ferrites with dual ferroic properties

The influence of partially substituted of barium ferrites by diamagnetic In and Ga ions with neutron diffraction method was studied. The substitution of Fe by In ions leads to increase of volume of unit cell while replacing with Ga ions insignificantly change the lattice parameters. The concentration dependence of the Tc Curie temperature as well as the magnetization is constructed. The refinement of the magnetic structure was carried out within the framework of Gorter’s model. The microstructural parameters of solid solutions BaFe12-xDxO19 (D= In and Ga; x = 0.1–1.2) were determined by the high-resolution neutron diffraction method.

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Contrast of Filament Bright Rims

International Astronomical Union Colloquium ◽

10.1017/s0252921100025628 ◽

1994 ◽

Vol 144 ◽

pp. 365-367

Author(s):

E. V. Kononovich ◽

O. B. Smirnova ◽

P. Heinzel ◽

P. Kotrč

Keyword(s):

High Altitude ◽

Line Profile ◽

Line Center ◽

Magnetic Structures ◽

The Mean

AbstractThe Hα filtergrams obtained at Tjan-Shan High Altitude Observatory near Alma-Ata (Moscow University Station) were measured in order to specify the bright rims contrast at different points along the line profile (0.0; ± 0.25; ± 0.5; ± 0.75 and ± 1.0 Å). The mean contrast value in the line center is about 25 percent. The bright rims interpretation as the bases of magnetic structures supporting the filaments is suggested.

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Dislocations, Ordering and Antiferromagnetic Domains in MnO

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069600 ◽

1970 ◽

Vol 28 ◽

pp. 522-523

Author(s):

D. J. Barber ◽

R. G. Evans

Keyword(s):

Electron Diffraction ◽

Single Crystal ◽

Optical Microscopy ◽

Defect Chemistry ◽

Magnetic Structures ◽

Optically Transparent ◽

Magnetic Features ◽

Antiferromagnetic Domains

Manganese (II) oxide, MnO, in common with CoO, NiO and FeO, possesses the NaCl structure and shows antiferromagnetism below its Neel point, Tn∼ 122 K. However, the defect chemistry of the four oxides is different and the magnetic structures are not identical. The non-stoichiometry in MnO2 small (∼2%) and below the Tn the spins lie in (111) planes. Previous work reported observations of magnetic features in CoO and NiO. The aim of our work was to find explanations for certain resonance results on antiferromagnetic MnO.Foils of single crystal MnO were prepared from shaped discs by dissolution in a mixture of HCl and HNO3. Optical microscopy revealed that the etch-pitted foils contained cruciform-shaped precipitates, often thick and proud of the surface but red-colored when optically transparent (MnO is green). Electron diffraction and probe microanalysis indicated that the precipitates were Mn2O3, in contrast with recent findings of Co3O4 in CoO.

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New type of domain boundaries in multilayer magnetic structures

Uspekhi Fizicheskih Nauk ◽

10.3367/ufnr.0169.199908h.0922 ◽

1999 ◽

Vol 169 (8) ◽

pp. 922 ◽

Cited By ~ 1

Author(s):

Aleksandr I. Morozov ◽

Aleksandr S. Sigov

Keyword(s):

Magnetic Structures ◽

Domain Boundaries ◽

New Type

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Structural and Magnetic Hysteresis Properties of Co-Zr Substituted Hexagonal Barium Ferrites

JOURNAL OF ADVANCES IN PHYSICS ◽

10.24297/jap.v7i1.1739 ◽

2015 ◽

Vol 7 (1) ◽

pp. 1346-1351

Author(s):

Ch.Gopal Reddy ◽

Ch. Venkateshwarlu ◽

P. Vijaya Bhasker Reddy

Keyword(s):

Magnetic Properties ◽

Single Phase ◽

Magnetic Hysteresis ◽

Grain Morphology ◽

Hexagonal Structure ◽

Ion Composition ◽

X Ray Diffraction ◽

Ceramic Method ◽

Barium Ferrites ◽

Xrd Patterns

Co-Zr substituted M-type hexagonal barium ferrites, with chemical formula BaCoxZrxFe12-2xO19 (where x = 0.0, 0.2, 0.4, 0.6, 0.8 and 1.0), have been synthesized by double sintering ceramic method. The crystallographic properties, grain morphology and magnetic properties of these ferrites have been investigated by X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM). The XRD patterns confirm the single phase with hexagonal structure of prepared ferrites. The magnetic properties have been investigated as a function of Co and Zr ion composition at an applied field in the range of 20 KOe. These studies indicate that the saturation magnetization (Ms) in the samples increases initially up to the Co-Zr composition of x=0.6 and decreases thereafter. On the other hand, the coercivity (Hc) and Remanent magnetization (Mr) are found to decrease continuously with increasing Co-Zr content. This property is most useful in permanent magnetic recording. The observed results are explained on the basis of site occupation of Co and Zr ions in the samples.

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Films, Needles, and Particles: A Comparative Study on the Ferroic Properties of Complex Oxides Nano-Structured in One, Two, and Three Dimensions

10.21236/ada604934 ◽

2014 ◽

Author(s):

Richard X. Fu ◽

Ryan C. Toonen ◽

Samuel G. Hirsch ◽

Mathew P. Ivill ◽

Melanie W. Cole

Keyword(s):

Comparative Study ◽

Complex Oxides ◽

Three Dimensions ◽

Ferroic Properties

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Effect of Reaction Time on Microwave Absorption Properties of Fe3O4 Hollow Spheres Synthesized via Ostwald Ripening

Materials ◽

10.3390/ma12182921 ◽

2019 ◽

Vol 12 (18) ◽

pp. 2921 ◽

Cited By ~ 1

Author(s):

Wei Huang ◽

Yujiang Wang ◽

Shicheng Wei ◽

Bo Wang ◽

Yi Liang ◽

...

Keyword(s):

Reaction Time ◽

Microwave Absorption ◽

Ostwald Ripening ◽

Impedance Matching ◽

Hollow Spheres ◽

Absorption Properties ◽

Microwave Absorption Properties ◽

Magnetic Structures ◽

Absorption Performance ◽

Microwave Absorption Performance

Hollow magnetic structures have great potential to be used in the microwave absorbing field. Herein, Fe3O4 hollow spheres with different levels of hollowness were synthesized by the hydrothermal method under Ostwald ripening effect. In addition to their microstructures, the microwave absorption properties of such spheres were investigated. The results show that the grain size and hollowness of Fe3O4 hollow spheres both increase as the reaction time increases. With increasing hollowness, the attenuation ability of electromagnetic wave of Fe3O4 spheres increases first and then decreases, finally increases sharply after the spheres break down. Samples with strong attenuation ability can achieve good impedance matching, which it does preferentially as the absorber thickness increases. Fe3O4 hollow spheres show the best microwave absorption performance when the reaction time is 24 h. The minimum reflection loss (RL (min)) can reach −40 dB, while the thickness is only 3.2 mm.

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Sol–gel magnetite inks for inkjet printing

Journal of Materials Chemistry C ◽

10.1039/c9tc00311h ◽

2019 ◽

Vol 7 (21) ◽

pp. 6426-6432 ◽

Cited By ~ 5

Author(s):

Denis S. Kolchanov ◽

Vladislav Slabov ◽

Kirill Keller ◽

Ekaterina Sergeeva ◽

Mikhail V. Zhukov ◽

...

Keyword(s):

Inkjet Printing ◽

Sol Gel ◽

Device Fabrication ◽

Magnetic Device ◽

Magnetic Structures

The article describes an easy-to-implement and print-ready composition for inkjet printing of magnetic structures, which can be used for security printing, coding, and marking, magnetic device fabrication or creation of micro-antennas.

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