The superconducting magnetoresistance effect (SMRE) observed in trilayers (TLs) consisting of a superconducting (SC) Nb interlayer and two outer ferromagnetic (FM) Ni80Fe20 and Co layers is studied. We observed that the SMRE exhibits a pronounced magnitude (R-max - R-min)/R-nor of order 45 % and 86 % for the NiFe-based and Co-based TLs, respectively. For the NiFe-based TLs, the dynamic transport behavior of the observed SMRE is presented through detailed I-V characteristics that exhibit a nonlinear character even extremely close to the critical temperature, T-c(SC). Also, the detailed evolution of the longitudinal and transverse components of the TL magnetization from close to well below T-c(SC) is presented. For the Co-based TLs, the obtained magnetization and transport data justify that a strict requisite for the observation of a pronounced SMRE across T-c(SC) is that the coercivities of the FM layers should be similar. The combined data on the NiFe-based and Co-based TLs show that across the superconducting transition the SMRE is influenced by out-of-plane stray-fields, attaining pronounced values when the respective coercive fields coincide, thus enabling the transverse magnetic coupling of the outer FM layers through the SC interlayer.

Zinc ferrites, ZnFe2O4 and zinc ferrite nanoparticles substituted with indium and yttrium, Zn1-xInxFe2O4 and ZnYxFe2-xO4 (0 <= x <= 0.3), were synthesized by co-precipitation method. We have investigated the effect of composition on the cation distribution in the spinel structure, and on the magnetic properties with a view to obtain magnetic ceramics with improved properties compared to their bulk counter parts. The results of X ray diffraction (XRD) and transmission electron microscopy (TEM) confirmed the nanoscale dimensions and spinel structure of the samples. The estimated crystallite size lies within the range 4-10 nm. Additional experiments had been conducted using a scanning mobility particle sizer spectrometer (SMPS) in order to measure the number size distribution of the nanoparticles. Mossbauer spectroscopy was used to investigate the cation distribution between the tetrahedral and octahedral sites and the formation of the partially inverse spinel. The study of the magnetic properties showed that the hysteresis loops do not saturate even in the presence of high magnetic fields, confirming the superparamagnetic single domain nature of the samples. The particle size and composition variations (e.g. addition of yttrium and indium) cause significant structural rearrangements which affect the magnetic behavior of these materials. (C) 2012 Elsevier Ltd and Techna Group S.r.l. All rights reserved.

Reduced-activation ferritic-martensitic steels are promising candidates for structural applications in future nuclear fusion power plants. Oxide dispersion strengthened ODS-Eurofer and Eurofer 97 steels were cold rolled to 80% reduction in thickness and annealed in vacuum for 1 h from 200 to 1350 degrees C to evaluate both their thermal stability and magnetic behavior. The microstructural changes were followed by magnetic measurements, in particular the corresponding variation of the coercive field (H-c), as a function of both annealing and tempering treatments. Results show that Y2O3 nanoparticles strongly affect the mechanical properties of ODS-Eurofer steel but leave their magnetic properties fairly unchanged when compared with Eurofer-97 steel. (C) 2012 Elsevier BM. All rights reserved.

In this paper, we present a patch antenna design and fabrication that uses a ferrimagnetic compound, Yttrium Iron Garnet (YIG), as part of its substrate. It is proved via both numerical simulations and experimental measurements, that with suitable application of an external magnetic field, a reconfigurable behavior in terms of the polarization characteristics can be achieved. The antenna is reconfigured from a single band linear polarized to a dual band circular polarized one, with different polarization sense in each resonance band. Mixtures containing YIG and epoxy resin in various consistencies have been examined.

Background: In hemodialysis (HD) patients, anemia relates to three main factors: insufficient production of erythropoietin; impaired management of iron; and decreased lifespan of red blood cells (RBCs). The third factor can relate to structural deterioration of RBCs due to extrinsic (extracorporeal circuit; biochemical activation and/or mechanical stress during dialysis) and intrinsic (uremic milieu; biochemical interference of the RBC membrane constituents with toxins) mechanisms. Herein, we evaluate information accessed with advanced imaging techniques at the cellular level. Methods: Atomic force and scanning electron microscopes were employed to survey intact RBCs (iRBCs) of seven HD patients in comparison to seven healthy donors. The extrinsic factor was investigated by contrasting pre- and post-HD samples. The intrinsic environment was investigated by comparing the microscopy data with the clinical ones. Results: The iRBC membranes of the enrolled HD patients were overpopulated with orifice-like (high incidence; typical size within 100-1,000 nm) and crevice-like (low incidence; typical size within 500-4,000 nm) defects that exhibited a statistically significant (P < 0.05) relative increase (+55% and +350%, respectively) in respect to healthy donors. The relative variation of the orifice and crevice indices (mean population of orifices and crevices per top membrane surface) between pre- and post-HD was not statistically significant (-3.3% and +4.5%, respectively). The orifice index correlates with the concentrations of urea, calcium, and phosphorus, but not, however, with that of creatinine. Conclusion: Extracorporeal circulation is not detrimental to the structural integrity of RBC membranes. Uremic milieu is a candidate cause of RBC membrane deterioration, which possibly worsens anemia.

In many cases, technological advances are based on artificial low-dimensional structures of heterogeneous constituents, thus called hybrids, that when come together they provide stand-alone entities that exhibit entirely different properties. Such hybrids are nowadays intensively studied since they are attractive for both basic research and oncoming practical applications. Here, we studied hybrids constituted of piezoelectric (PE) and ferromagnetic (FM) components in the form FM/PE/FM, ultimately aiming to provide means for the controlled modulation of the properties of the FM electrodes, originating from the strain imposed to them by the PE mediator when an electric field is applied. The PE component is in single crystal form, 0.71Pb(Mg1/3Nb2/3)O-3-0.29PbTiO(3) (PMN-PT), while the FM outer layers are Cobalt (Co) in thin film form. Detailed magnetization measurements performed under variation of the electric field applied to PMN-PT demonstrated the efficient modulation of the properties of the Co electrodes at low temperature (coercive field modulation up to 27% and saturation magnetization absolute modulation up to 4% at T = 10K for electric field not exceeding 6 kV/cm). The modulation degree faints upon increase of the temperature, evidencing that the thermal energy eventually dominates all other relevant energy scales. Candidate mechanisms are discussed for the explanation of these experimental observations. The results presented here demonstrate that commercially available materials can result in quantitatively noticeable effects. Thus, such elemental Co/PMN-PT/Co units can be used as a solid basis for the development of devices. (C) 2013 AIP Publishing LLC.