Static Ferromagnetic Modulation Revealed by Neutron Scattering in La1?xCaxMnO3

Mn perovskites La_1–x Ca _x MnO₃ (0x0.1) have been studied by small angle neutron scattering (SANS) and elastic neutron scattering (ESANS). At low temperature, both experiments reveal a broad modulation centered at the same q _m whatever the q direction. This scattering pattern is typical of a liquid-like distribution of similar magnetic droplets, or large magnetic polarons.     

A compact split step Padé scheme for higher-order nonlinear Schrödinger equation (HNLS) with power law nonlinearity and fourth order dispersion

In this paper we propose a compact split step Padé scheme (CSSPS) to solve the scalar higher-order nonlinear Schrödinger equation (HNLS) with higher-order linear and nonlinear effects such as the third and fourth order dispersion effects, Kerr dispersion, stimulated Raman scattering and power law nonlinearity. The stability of this method has been proved. It has been shown as well that the CSSPS method gives the same results as classical numerical methods like the split step Fourier method and Crank–Nicholson (CN) method but it presents many advantages over theme. It is more efficient. This proposed scheme is well suited to higher-order dispersion effects and readily generalized for nonlinear and dispersion managed fibers. We tested this scheme for the case of the quintic nonlinearity and confirmed that this effect has no significant role on the propagation of single solitons.     

Static Ferromagnetic Modulation Revealed by Neutron Scattering in La1−xCaxMnO3

Mn perovskites La_1?x Ca _x MnO₃ (0≤x0.1) have been studied by small angle neutron scattering (SANS) and “elastic” neutron scattering (ESANS). At low temperature, both experiments reveal a broad modulation centered at the same q _m whatever the q direction. This scattering pattern is typical of a liquid-like distribution of similar magnetic droplets, or large magnetic polarons.     

Analyse et modélisation de la permittivité effective statique de la ligne microruban suspendue

New numerical quasi-static model for the computer aided design (CAD) and analysis of suspended microstrip lines is reported. This model is applicable up to ε_r = 20 and over the range 0.001 ≤ u ≤ 1000, where u = w/h ₁ is the structure’s variable (w is the width of the strip and h ₁ is the air gap’s thickness). The practical cases are limited to a thickness h ₁ of the same order of h ₂ which is the dielectric’s thickness. This yields to choose 0.5 ≤ m ≤ 1.5. The parameter m is dependent on the structure’s variable u. This model is conceived to corroborate the results of the variational approach in any point of its ranges of validity, with a raised error with 1.2%. Although the variational approach allows accurate values of the effective permittivity, but the computing time is relatively high which quickly becomes prohibitory if the Finished Coupled Elementary Lines method is used. The present model is an improvement over the previous variational method as it not only takes lower computing time but it also valid up to high values of ε_r and over the range 0.001 ≤ u ≤ 1000. This work is important by the fact that it seeks to visualise the formal model of the effective permittivity, generally masked in a direct variational treatment.     

Perception-based microtuning over MIDI networks

MIDI has intrinsic limitations that have held back the development of flexible microtunable systems. The author evaluates previous solutions and address the problem of pervasive microtuning in MIDI networks within the context of the general weaknesses and underusage of MIDI technology. Then the author describes the prototyped and patent-pending solution called U-Tune, which involves implementing pervasive microtuning over a MIDI network.     

Induced electrodeposition of tungsten with nickel from acidic citrate electrolyte

Induced electrodeposition of Ni–W alloys was carried out onto steel substrates from acidic citrate baths (pH 4.5) under different conditions of concentration of electrolyte, current density and temperature. Bright and highly adherent Ni–W deposits were successfully obtained with a relatively high cathodic current efficiency CCE (80–85%). The CCE increases greatly with increasing pH and Ni²⁺ ion content in the bath. The W% in the alloy deposits is in the range of 4–20 wt% depending on the operating condition. The W content in the deposit was found to increase with an increase in Ni²⁺ ion content, pH and temperature. The surface morphology was examined by scanning electron microscopy while the structure of the alloy was examined by X-ray diffraction analysis.