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31.
Self-assembled one-dimensional (1D) zinc oxide (ZnO) rods and three-dimensional (3D) cupric oxide (CuO) cubes like nanostructures with a mean crystallite size of approximately 33 and 32 nm were synthesized through chemical route in the presence of polyvinylpyrrolidone (PVP) under mild synthesis conditions. The technique used for the synthesis of nanoparticles seems to be an efficient, inexpensive and easy method. X-Ray diffraction patterns confirmed well crystallinity and phase purity of the as prepared samples, followed by the compositional investigation using Fourier Transform Infrared (FT-IR) spectroscopy. The formation of ZnO nanorods and CuO nanocubes like structures were through Scanning Electron Microscopy (SEM) images. The mechanism and the formation factors of the self-assembly were discussed in detail. It was clearly observed from results that the concentration of precursors and PVP were important factors in the synthesis of self-assembly ZnO and CuO nanostructures. These self-assembly nanostructures maybe used as novel materials in various potential applications.  相似文献   
32.
This is the report of flavor physics and model building working group at WHEPP-9. While activites in flavor physics have been mainly focused on B-physics, those in model building have been primarily devoted to neutrino physics. We present summary of working group discussions carried out during the workshop in the above fields, and also briefly review the progress made in some projects subsequently.  相似文献   
33.
Structure functions obtained from high energy neutrino and antineutrino scattering from an iron target are presented. These were extracted from the combined data of Fermilab experiments E616 and E701; these utilized narrow band beam runs between 1979–1982. The structure functions are used to test the validity of quarkparton model (QPM) predictions and to extract the QCD scale parameter Λ from fits to the Altarelli-Parisi equations.  相似文献   
34.
Employing the γ-ray perturbed angular distribution technique, we have measured the magnetic hyperfine field of 54Fe in tetragonal and orthorhombic structural phases of SrFe2As2. In the tetragonal phase, the magnetic response of 54Fe shows Curie-Weiss type local susceptibility, indicating the presence of localized moment on Fe. The temperature dependence of the hyperfine field of 54Fe reflects quasi-two dimensional first order magnetic transition at 200 K. Our data indicate that Fe moments in the magnetically ordered phase of SrFe2As2 may be canted out of the ab-plane.  相似文献   
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The effects of a magnetic field on jets of an electrically conducting fluid flowing over a curved surface, in the presence of a variable normal magnetic field, are studied. It is noted that the convex surface curvature h and the magnetic interaction parameter m, in small perturbation similarity solution have qualitatively similar effects. They increase the mass flux, decrease the momentum flux, decrease the wall shear and cause an adverse pressure gradient in the flow field.  相似文献   
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The plasma region under investigation is separated from the discharge region by a mesh grid. Plasma potential and electron number densities and electron temperatures under bi‐Maxwellian approximation for electron distribution function of the multi‐dipole argon plasma are measured. The cold electrons in the diffusion region are produced by local ionization. The hot electrons are the ionizing electrons behaving as Maxwellian. The electron trapping process in the discharge region is produced by potential well due to positive plasma potential with respect to the anode and by a repulsive grid. The dependence of ratios of the density of the hot to the cold electrons NE (=Neh/Nec) and hot to cold electron temperature T(=Teh/Tec) in the diffusion region on the depth of the potential well has been investigated. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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Dispersion characteristics and wave impedance of trapped coupled image guides are computed by using mode matching techniques. Dispersion curves for trapped coupled image guide are plotted for various dielectric materials and dimensional parameters. The hybrid directional couplers in the above configuration have been theoretically designed by computing the normalization propagation constant.  相似文献   
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