By using a two-step method, we successfully synthesized the iron based new superconductor LaFeAsO0.9F0.1−δ. The resistive transition curves under different magnetic fields were measured, leading to the determination of the upper critical field Hc2(T ) of this new superconductor. The value of Hc2 at zero temperature is estimated to be about 50 Tesla roughly. In addition, the Hall effect and magn...

Scaling theory, duality symmetry, and numerical simulations of a random network model are used to study the magnetoresistance of a metal/insulator/perfect conductor composite with a disordered columnar microstructure. The phase diagram is found to have a critical line which separates regions of saturating and nonsaturating magnetoresistance. The percolation problem which describes this line is ...

Layered birnessite-type manganese oxide was prepared by a simple redox sol–gel reaction involving hydroxylamine and permanganate in alkaline medium. IR, XRD, Auger electron spectroscopy, EPR, TGA and cyclic voltammetric characteristics of the birnessites are presented. The birnessite was examined for its cathode performance in zinc-, magnesiumand lithium-based cells. Bismuth and lead exchanged ...

Thin polyethyleneterephthalate (PET) layers with Fe nanoparticles (NPs) were synthesized by high-fluence ion implantation. Temperature dependence of conductance and magnetoresistance, were studied as a function of ion fluence. It is found that the implantation with fluences of about 1.0×10 cm causes high enough concentration of metal inclusions to provide conditions for electrical percolation t...

hcp(101̄0) Co/Re superlattices were grown via magnetron sputtering on Al2O3(112̄0) substrates. The thickness of the Co layers was approximately 1.8 nm with the Re layer thickness varying between 0.5 nm and 3.0 nm. Low angle x-ray reflectivity revealed that for our growth conditions the interfacial roughness is approximately 0.4 nm in each material at each interface. High angle x-ray diffraction, ...

Fractional calculus is considered when derivatives and integrals of non-integer order are applied over a specific function. In the electrical and electronic domain, the transfer function dependence of a fractional filter not only by the filter order n, but additionally, of the fractional order α is an example of a great number of systems where its input-output behavior could be more exactly mod...

A new magnetorheological elastomer composite (MRE) was developed with a resistance which is strongly sensitive both to temperature and pressure. The electrical resistance of this MRE was investigated versus pressure and temperature. The resistance of the composite was recorded versus pressure for seven different values of the temperature. The mechanism of electrical conduction was modeled and a...

2014 This work presents an overall view of the measurements concerning the galvanomagnetic coefficients in the weak-field case with an attempt to emphasize the physical significance of the results. The method is based on the anisotropy induced in the electrical behaviour by the magnetic field. Emphasis is also given in explaining the magnetoresistance skewness effect. A comparison with the clas...