• فهرس المقالات 81.07

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        1 - Williamson-Hall analysis in estimation of lattice strain in nanometer-sized ZnO particles
        VD Mote Y Purushotham BN Dole
        AbstractZnO nanoparticles were prepared by coprecipitation method at 450C. X-ray diffraction result indicates that the sample is having a crystalline wurtzite phase. Transmission electron microscopy (TEM) result reveals that the ZnO sample is spherical in shape with an أکثر
        AbstractZnO nanoparticles were prepared by coprecipitation method at 450C. X-ray diffraction result indicates that the sample is having a crystalline wurtzite phase. Transmission electron microscopy (TEM) result reveals that the ZnO sample is spherical in shape with an average grain size of about 50nm. X-ray peak broadening analysis was used to evaluate the crystalline sizes and lattice strain by the Williamson-Hall (W-H) analysis. All other relevant physical parameters such as strain, stress, and energy density values were also calculated using W-H analysis with different models, viz, uniform deformation model, uniform deformation stress model and uniform deformation energy density model. The root mean square strain was determined from the interplanar spacing and strain estimated from the three models. The three models yield different strain values; it may be due to the anisotropic nature of the material. The mean particle size of ZnO nanoparticles estimated from TEM analysis, Scherrers formula and W-H analysis is highly intercorrelated. تفاصيل المقالة
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        2 - Synthesis and characterization of gold nanoparticles via submerged arc discharge based on a seed-mediated approach
        Ali Akbar Ashkarran
        AbstractGold nanoparticles were prepared via liquid arc discharge technique using a seed-mediated approach in solution and characterized by dynamic light scattering, UV–vis spectroscopy, X-ray diffraction, optical imaging, and atomic force microscopy. A surface plasmon أکثر
        AbstractGold nanoparticles were prepared via liquid arc discharge technique using a seed-mediated approach in solution and characterized by dynamic light scattering, UV–vis spectroscopy, X-ray diffraction, optical imaging, and atomic force microscopy. A surface plasmon resonance was observed around 520 nm based on optical absorption spectroscopy of as-prepared samples at 15 A arc current in HAuCl4 solution. It was found that sodium citrate acts as a stabilizer and surface capping agent of the colloidal nanoparticles. It was found that the intensity of the plasmonic peak of as-prepared gold nanoparticles in 1 min arc duration gradually increases due to seed mediation up to 6 h. The formation time of gold nanoparticles in higher seed concentrations is less than the lower seed concentrations. تفاصيل المقالة