Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 5

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Perminvar Effect in Amorphous Hitperm Alloy

100%
Varga M., Varga R., Vojtanik P., Komova E.
Acta Physica Polonica A
|
2008
|
vol. 113
|
issue 1
119-122
EN
Influence of the directional ordering on magnetization processes in the amorphous Fe_{44.5}Co_{44.5}Zr_7B_4 alloy was investigated in the temperature region of 27 to 300°C for stabilization times of up to 1000 min by means of the Perminvar effect. The time-temperature dependent Perminvar effect was found to be very sensitive on the stage of the domain structure stabilization. The Perminvar critical fields H_{CR} were shifted to higher values with increasing stabilization temperatures and times. At lower temperatures, the susceptibility increases over wide range of the measuring fields. Stabilization at higher temperatures causes that the susceptibility abruptly increases in the narrow field range. The record critical field H_{CR} =246 Am^{-1} was obtained.
2
Content available remote

Thermal Properties of Conducting Polypyrrole Nanotubes

88%
Rudajevová A., Varga M., Prokeš J., Kopecká J., Stejskal J.
Acta Physica Polonica A
|
2015
|
vol. 128
|
issue 4
730-736
EN
Thermal properties of polypyrrole nanotubes synthesized by the chemical oxidation of pyrrole with iron(III) chloride in the presence of methyl orange as structure-guiding template, have been investigated. As-prepared polypyrrole salt and corresponding base were compressed into pellets. Thermogravimetric analysis has shown that the heating/cooling of both polymers is connected with water desorption/re-absorption. This process influences all temperature dependences of the thermophysical properties. The specific heat of both polypyrrole forms was the same at 35°C. The thermal diffusivity of polypyrrole base was lower than that of the salt. The dilatational characteristics are strongly influenced by water desorption/re-absorption. Water desorption is connected with the contraction of polypyrrole and its re-absorption with the expansion of polypyrrole. The electrical resistivity was measured, in analogy to thermal experiments, by a four-point van der Pauw method. The electrical resistivity was 0.016 and 10.2 Ωcm at room temperature, for both materials. The electrical resistivity was also influenced by water desorption/re-absorption as well as other thermophysical properties.
3
Content available remote

Stress Dependence of the Switching Field in Glass Coated Microwires

76%
Komová E., Varga M., Varga R., Vojtaník P., Torrejon J., Provencio M., Vázquez M.
Acta Physica Polonica A
|
2008
|
vol. 113
|
issue 1
135-138
EN
Here we present the study of the stress dependence of the switching field in amorphous glass-coated magnetic microwire of composition FeNiMoB. Samples were heat treated in the temperature range from 250°C up to 500°C in order to obtain relaxed and nanocrystalline state. As-cast microwire shows strong stress dependence of the switching field, which decreases with the temperature of annealing. The sample is almost not stress dependent after heat treatment at 425°C, because the magnetostriction vanishes. However, the strongest stress dependence was found for the microwire annealed at 400°C, just below the optimal annealing temperature to obtain the nanocrystalline state.
4
Content available remote

Magnetoimpedance Effect in Field Annealed (FeNi)_{78}Nb_{7}B_{15} Amorphous and Nanocrystalline Bilayer Ribbons

76%
Varga M., Marcin J., Capik M., Janičkovič D., Švec P., Škorvánek I.
|
|
vol. 126
|
issue 1
122-123
EN
The influence of the magnetic field annealing on the magnetoimpedance effect has been investigated in rapidly quenched (Fe_{0.5}Ni_{0.5})_{78}Nb_{7}B_{15} monolayer and bilayer thin ribbons. The highest impedance ratio value (ΔZ/Z)_{max}=72% and the maximum field sensitivity η_{max}=12 %/Oe was obtained in the bilayer ribbon, annealed under longitudinal magnetic field at 773 K that exhibited nanocrystalline structure. The higher values of (ΔZ/Z)_{max} in bilayer ribbons, as compared to their monolayer counterparts, are attributed to the increased ratio of their thickness to the penetration depth.
5
Content available remote

Directional Ordering in Amorphous Fe_{43}Ni_{43}Zr_7Cu_1B_6 Ferromagnetic Alloys

76%
Varga M., Varga R., Vojtaník P., Hernando B., Prida V., Santos J., Pérez M.
|
|
issue 5
804-806
EN
Development of the atomic directional ordering in the Fe_{43}Ni_{43}Zr_7Cu_1B_6 alloy, during its conventional the same as after transverse magnetic field annealing, was experimentally studied by the amplitude dependence of susceptibility and hysteresis loops measurements, respectively. Diffusion processes of the mobile atoms caused perminvar effect, decrease of the initial susceptibility, increase of the critical field, and linear shape of the hysteresis loop. Uniaxial magnetic anisotropy, created during magnetic field annealing of the FeNiZrCuB alloy, was confirmed also by observation of the surface domain structure.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.