Zobrazeno 1 - 10
of 281
pro vyhledávání: '"E. Pollert"'
Autor:
E. Pollert, Miroslav Maryško, Z. Jirák, Pavel Veverka, Karel Knížek, P. Kaspar, Ondřej Kaman, Miroslav Veverka, Vladimir Šepelák, Martin Burian
Publikováno v:
Journal of Nanoparticle Research. 13:1237-1252
The magnetic nanoparticles of La0.75Sr0.25MnO3 perovskite manganite with a controlled size were prepared via sol–gel procedure, followed by thermal treatment and subsequent mechanical processing of the resulting raw product. The prepared materials
Autor:
Karel Knížek, E. Pollert, Karel Závěta, Miroslav Veverka, Ondřej Kaman, Pavel Veverka, Miroslav Maryško, Z. Jirák
Publikováno v:
Journal of Magnetism and Magnetic Materials. 322:2386-2389
Nanoparticles of the single spinel phase Co1−xZnxFe2O4+γ of mean size 3–23 nm, as determined by X-ray diffraction analysis, were synthesized by the co-precipitation method followed by a temperature treatment. Magnetic studies carried out in the
Autor:
Pavel Veverka, J. Boháček, E. Pollert, Karel Knížek, Etienne Duguet, Josik Portier, Sébastien Vasseur
Publikováno v:
Journal of Magnetism and Magnetic Materials
Journal of Magnetism and Magnetic Materials, Elsevier, 2007, 309 (1), pp.106-112. ⟨10.1016/j.jmmm.2006.06.019⟩
Journal of Magnetism and Magnetic Materials, Elsevier, 2007, 309 (1), pp.106-112. ⟨10.1016/j.jmmm.2006.06.019⟩
Systematic study was devoted to the synthesis of hexagonal strontium ferrite nanoparticles employing polyvinylalcohol as stabilizing agent. Preliminary experiments allowed to select an optimal sol having molar ratio Sr 2 + / Fe 3 + = 12 , weight rati
Publikováno v:
Czechoslovak Journal of Physics. 56:E83-E91
Particles of Fe oxide were prepared by chemical coprecipitation and their sizes were shown by TEM and confirmed by XRD to be in the range of 5 nm. The Mossbauer spectra at 120K clearly indicated the absence of magnetite and presence of the maghemite
Autor:
J. Boháček, Miroslav Maryško, Karel Knížek, Daniel Horák, E. Pollert, A. Lančok, Michal Babic, Karel Závěta
Publikováno v:
Journal of Magnetism and Magnetic Materials. 306:241-247
Magnetic poly(glycidyl methacrylate) (PGMA) microspheres were prepared by emulsion polymerization of glycidyl methacrylate (GMA) in the presence of (carboxymethyl)dextran (CM-dextran)-stabilized iron oxide colloid. Scanning electron microscope (SEM)
Autor:
D. Rybicki, K. Knizek, Miroslav Maryško, E. Pollert, P. Veverka, Z. Jirák, Marcin Sikora, Cz. Kapusta, P.C. Riedi
Publikováno v:
physica status solidi c. 3:155-158
We report on a 55Mn NMR study of the La0.75Sr0.25MnO3 nanoparticles of the average grain size 33 nm and 114 nm at 4.2 K and 77 K and at applied field of 0, 0.2 and 0.5T. A dominant signal from the double exchange (DE) controlled metallic ferromagneti
Publikováno v:
Journal of Solid State Chemistry. 174:466-470
The influence of the cobalt substitution for manganese ions in the series of the perovskites Pr 0.8 Na 0.2 Mn (1− x ) Co x O 3 (0⩽ x ⩽0.1) was investigated. The study of electric and magnetic properties was carried out on sintered polycrystalli
Autor:
Radomír Kužel, Karel Knížek, E. Pollert, M. Hervieu, S. Vratislav, M. Dlouhá, Miroslav Maryško, Z. Jirák, Jiri Hejtmanek
Publikováno v:
Journal of Magnetism and Magnetic Materials. 250:275-287
The mixed-valence manganites Pr 1− x Na x MnO 3 have been investigated by neutron diffraction, electric transport and magnetic measurements. Similarly to related systems with divalent alkali earths, the increasing monovalent sodium substitution dec
Publikováno v:
Physica C: Superconductivity. 371:111-116
The equilibrium formation conditions of the HgBa2CaCu2O6+δ phase were investigated by experiments based on reaction of HgO, BaO, CaO and CuO in sealed silica tubes. While the oxygen partial pressure during the synthesis was controlled by suitable re
Publikováno v:
Journal of Magnetism and Magnetic Materials. 246:290-296
The X-ray diffraction, magnetic, electric and specific heat measurements have been performed on single crystals Pr 1− x Sr x MnO 3 close to boundary between the Pbnm and I4/mcm perovskite types where subtle changes of composition are found sufficie