The effect of different AC current density on the magnetoimpedance of CoFeMoSiB amorphous ribbons in the presence of iron oxide nanoparticles water based ferrofluid

Selected measurements were performed at SGIker services of UPV-EHU. This work was supported by Spanish ACTIMAT grant. We thank A.P. Safronov, I.V. Beketov and Yu. P. Novoselova for special support

Magnetic properties of FeNi nanoparticles obtained by the elelctric explosion of wire

Selected measurements were performed at SGIker services of UPV-EHU. This work was supported by the Russian Federation state assignment # 0389-2014-0002 and Spanish MECMAT 2014-55049-C2-1-R grant

Magnetic properties of FeNi nanoparticles obtained by the elelctric explosion of wire

Selected measurements were performed at SGIker services of UPV-EHU. This work was supported by the Russian Federation state assignment # 0389-2014-0002 and Spanish MECMAT 2014-55049-C2-1-R grant

OBTAINING OF COMPLEX NANOPARTICLES BY THE SPARK DISCHARGE METHOD

In the research, several samples of complex oxide FeAl2O4 nanopowders and intermetal-lic FeAl nanopowders were obtained by the spark discharge method. X-ray diffraction anal-ysis and BET analysis, were performed and obtained dependence of electrode mass loss on input energy into discharge circuit

Magnetic Nanoparticles of (Co0.94Fe0.06)72.5Si12.5B15 and Fe78Si9B13 obtained by electric explosion of amorphous wires

Magnetic nanoparticles (MNPs) were produced by the electric explosion of wire method (EEW) using (Co0.94Fe0.06)72.5Si12.5B15 and Fe78Si9B13 amorphous wires. The wires were exploded in Ar atmosphere at 0.12 MPa. After the explosion the surface of all produced nanoparticles was passivated with oxygen. The produced MNPs are spherical low aggregated particles with average size below 37 nm and rather narrow size distributions with geometric standard deviation less than 1.7. Both materials are multiphase and contain up to 23 wt % of amorphous phase. © 2015 Trans Tech Publications, Switzerland

Active surface modification for iron nanopowders produced by wire electrical explosion

The surface modification of metal iron nanopowders produced by wire electrical explosion (WEE) followed by immediate treatment with hexane, toluene, chloroform, and polymer solutions in hexane and toluene is investigated. It has been shown the nanopowders produced in the inert gas environment are shown to interact due to their active surface both with liquid media and with modifiers dissolved in them. X-ray diffraction and thermal analysis, including mass spectrometry, show that hexane is an inert liquid medium in respect to iron nanopowders, toluene treatment causes carbon deposition into the nanoparticle surface layers, and chloroform chemically interacts with iron nanoparticles with a high yield of FeCl 2. Thermal analysis and transmission electron microscopy show that treating nanopowders with an oleic acid (OA) solution in hexane and isoprene rubber and polystyrene solutions in toluene results in the formation of a polymeric coating with a thickness of 3-6 nm at the nanoparticle surface. The polymer amount adsorbed at the surface reaches 0. 4 mg/m 2 depending on the polymer concentration in the solution. The deposited polymer layer has a loose structure formed by macromolecules adsorbed within the ball conformation. © 2012 Pleiades Publishing, Ltd

Oxygen isotope exchange in nanosized powders of the Al2O3 oxide

Oxygen isotope exchange (OIE) between nanosized powders of the aluminum oxide Al2O3 and oxygen-containing gases 18O2 and C 18O2 has been studied in a temperature range of 100-500°C. The con-centration of the oxygen isotope 18O in the powders was determined by nuclear microanalysis technique (NRA). It has been shown that for this oxide the OIE exhibits a significant size effect. It has been established that the OIE of the Al2O3 nanopowder is characterized by a specific time dependence of the concentration of the 18O isotope at the surface of grains and by a low level of the content of 18O in the oxide. A linear depen-dence of the concentration of 18O in the nanopowders on the specific surface of the nanoparticles has been revealed. The experimental data are discussed in terms of several models of the process of isotope exchange. © Pleiades Publishing, Ltd., 2012

MEASURING DISCHARGE ENERGY IN THE INSTALLATION OF NANOPARTICLES SYNTHESIS BY THE SPARK DISCHARGE METHOD

A new method of waveform processing that has not been used before is proposed in order to determine the electrode drop in voltage and energy introduced into the discharge gap. The method can serve as a useful complement to existing methods