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This paper studies the dynamics of optical solitons in multi-dimensions with spatio-temporal dispersion and non-Kerr law nonlinearity. The integrability aspect is the main focus of this paper. Five different forms of nonlinearity are considered — Kerr law, power law, parabolic law, dual-power law and log law nonlinearity. The traveling wave hypothesis, ansatz approach and the semi-inverse variational principle are the integration tools that are adopted to retrieve the soliton solutions to the governing equation. As a result, several constraint conditions arise out of the integration process and represent necessary conditions for the existence of solitons.

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International audienceIncorporation of the doping element Zn in the temperature range (550–700 °C) and the impact on structural and electrical properties of CuInSe2 material are investigated. X-ray diffraction patterns showed the chalcopyrite nature of the pure and doped CuInSe2 and revealed that diffusion temperature governs particle size as well as tensile strain. The calculated lattice parameters and cell volumes revealed that Zn diffuses in CuInSe2 by substitution on Cu sites. Electrical properties of the material have been investigated using a contact-less technique based on high frequency microwave (HF). It is found that Zn atoms influence the defect equilibrium resulting in the conversion of the conduction type. The conductivity of the samples has been found increasing as the diffusion temperature increases

Nanostructured Powders of Ni-20wt%Al and Ni-50wt%Al Were Prepared, by Mechanical Alloying under an Argon Atmosphere, from Elemental Ni and Al Powders Using a Planetary Ball Mill (type Fritsch P7) for Different Times (0.5-24h).). Microstructural and Structural Features of the Final Products Were Characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). the Results of the XRD Shows the Formation of the B2 (Ni Al) Phase after 2 Hours of Milling for both Systems. Also Detected Was the Ni3al Phase in Ni80al20after 4 Hours. Crystallite Size Refinement of the Final Product Occurred down to Nanometer Scales when the Milling Time Increased, and Attained 17 Nm in the Ni50al50System and 20 Nm in the other System, at 24 Hours. this Decrease in Crystallite Size Is Accompanied by an Increase in the Interval Level Strain. the Kinetics of Al Dissolution during the Milling Process of Ni50al50System Can Be Described by Two Regimes, Characterised by Different Values of Avrami Parameters which Are Calculated by Using the Johnson–Mehl–Avrami Formalism.

In the present study, a sol-gel dip-coating process was used to deposit almost stress free highly c-axis oriented nanostructured ZnO thin films on glass substrates. The effects of low silver doping concentration (Ag ˂ 1 at.%) on the structural, morphological and optical properties of such films were investigated using different characterization techniques. X-ray diffraction (XRD) measurements Contribution/ OriginalityThis study is one of very few studies which have investigated the preparation of low Agdoped ZnO thin films by the sol-gel dip-coating technique. It was put into evidence that incorporation of low Ag concentrations (Ag ˂ 1 at.%) in ZnO can indeed improve its physical properties. 2016 Vol. 4, No. 1, pp. 15-28 ISSN(e): 2311-4746 ISSN(p): 2311-7435 DOI: 10.18488/journal.63/2016 International Journal of Natural Sciences Research INTRODUCTIONIn recent years, zinc oxide (ZnO) has emerged as a promising material for a large number of fundamental and applied fields due to its numerous interesting characteristics including direct wide band gap (3.37 eV) semiconductor with a large excitation binding energy (60 meV [18]. Among these approaches, the sol-gel process has attracted large attentions due to its simplicity, low cost, easy adjusting composition and dopants, homogeneity on the molecular level and lower crystallization temperature.ZnO doping with selective elements is the most effective alternative to improve its structural, electrical, magnetic, and optical properties without any change in the crystalline structure [19]; [20]. Among these elements, Ag has been one of the most extensively used dopants whose effects on ZnO thin film properties have been widely investigated [17] [30]. Furthermore, only moderate or high Ag doping levels where studied. In this context, we complete and enrich our understanding of Ag doped ZnO films via the investigation of the influence of low Ag doping concentrations (Ag ˂ 1 at.%) on ZnO thin films properties. In the present work, ZnO thin films have been deposited onto glass substrates using a sol-gel dip-coating process. A systematic study was conducted to reveal the effect of low silver doping concentration on the structural, morphological and optical properties by using various characterization techniques.

Commercial grade A1100 aluminum specimens, widely used in deep drawing, is subjected to rolling followed by severe plastic deformation by Equal Channel Angular Pressing (ECAP). The ECAP die is designed and built in 42CrMo4 steel, hyper-hardened. It has a bent channel with an internal angle 𝜑=115° and an external angle ψ = 8°. The used deformation paths are the conventional route A as well as a non-conventional route noted Ci. The ECAP process is carried out at room temperature. The lowering speed of the movable crosshead of the press is 0.5 mm/s. The rolled and then extruded aluminum properties are studied by means of micro-hardness measurements, tensile tests and X-ray diffraction. Hardening is observed from the first pass, for both routes. The ultimate tensile strength presents a small variation for route A and decrease for route Ci. The elongation to failure increase for both A and Ci routes. The average grain diameter is on the order of 2,9µm after rolling and 1,3 µm after ECAP process in one pass.

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