in this research controlled coating of magnetite (fe3o4) nanoparticles with sio2 was investigated. the fe3o4 nanoparticles were synthesized via chemical co-precipitation and then coated by silica according to stober method. effects of tetra ethyl ortho silicate (teos) concentration and ethanol to teos on the coating thickness were investigated. x-ray powder diffraction, fourier transform infrar...

surface topography and ultrastructure of dried cysts of artemia parthenogenetica (vedaranyam population) and bisexual artemia sp. (kelambakkam population) were studied electron microscopically in order to identify the bisexual strain, inhabiting covelong salterns, kelambakkam, south india. the scope of this study is to provide substantial information for further characterization of these artemi...

objective(s): this paper describes coating of magnetite nanoparticles (mnps) with amorphous silica shells.   materials and methods: first, magnetite (fe3o4) nps were synthesized by co-precipitation method and then treated with stabilizer molecule of trisodium citrate to enhance their dispersibility. afterwards, coating with silica was carried out via a sol-gel approach in which the electrostati...

In this work core-shell structure Fe3O4@SiO2@meso-SiO2 microsphere has been successfully prepared. An inorganic magnetic core has been coated with multi-shell structure, dense nonporous silica as an inner layer and mesoporous silica as an outer layer. The dense silica shell can enhance the stability and minimize the negative effect of acidic condi...

core-shell nanostructures are emerging as more important materials than alloy nanostructures and have much more interesting potential applications in various fields. in this work, we demonstrated the fast and facile synthesis of core-shell nanoparticles consisting of pt thin layer as the shell and ni nanoparticles as the cores. the described method herein is suitable for large-scale and low-cos...

in order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. to do this we have investigated optical waveguide both with and without optical pumping. the rate of absorption and emission using an array of algaas/gaas quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. by con...

Shell structures are extensively used in engineering due to their efficient load-carrying capacity relative to material volume. However, large-span shells require additional supporting structures to strengthen fragile regions. The problem of designing optimal stiffeners is therefore becoming a major challenge for shell applications. To address it, we propose a computational framework to design ...