in this paper, the mer-co(nh3)3(no2)3 complex was used as a new precursor for synthesizing spinel-type cobalt oxide nanoparticles (co3o4nps).thermal decomposition of the complex at low temperature (175 °c) resulted in the co3o4nps without using expensive and toxic solvents or complicated equipment. xrd, ft-ir, sem, edx, and tem were employed to characterize the product, and its optical and magn...

Apart from large surface areas, low activation energies are essential for efficient reactions, particularly in heterogeneous catalysis. Here, we show that not only the size of nanoparticles but also their detailed morphology can crucially affect reaction kinetics, as demonstrated for mass-selected, soft-landed, and oxidized cobalt clusters in a 6 nm to 18 nm size range. The method of reflection...

For spintronic devices excited by a sudden magnetic or optical perturbation, the torque acting on the magnetization plays a key role in its precession and damping. However, the torque itself can be a dynamical quantity via the time-dependent anisotropies of the system. A challenging problem for applications is then to disentangle the relative importance of various sources of anisotropies in the...

1 Food Toxicology & Contaminants Departmnt, National Research Center, Dokki, Cairo, Egypt. 2 Nutrition Physiology and Toxicology Laboratory (NUTOX), INSERM U866, Bourgogne University, 1 Esplanade Erasme, F-21000 Dijon, France. 3 ProBioGem Laboratory, EA 1026, Polytech'Lille-IUT "A" Bd Paul Langevin, Villeneuve d'Ascq cedex, Université Lille Nord de France, France. 4 Food Science and Technology,...

Nanoparticles of iron-cobalt have attracted great interest in recent years because of their unique physical and chemical properties because of their industrial importance in preparing magnetic recording materials, pigments, catalysts, etc. With an objective to develop magnetic materials with high saturation magnetization Fe-Co nanosysytems were synthesized by method of chemical reduction reacti...

Using photoemission electron microscopy, we study the magnetization orientation in single 5-25 nm iron particles coupled to a ferromagnetic cobalt support. We find a noncollinear alignment between the particle and substrate magnetization above a particle size of approximately 6 nm and a parallel alignment for smaller sizes. Numerical calculations reveal a transition from an exchange-dominated t...

Magnetic CoFe2O4 nanoparticles were synthesized via a simple chemical reaction using precipitation method. The obtained materials consist of ferrite particles with average diameter of 25 nm. The effect of different surfactants such as cationic, anionic and neutral on the morphology of the products was investigated. Scanning electron microscopy was used to study the structure and particle size o...

The surface science of heterogeneous metal catalysis uses model systems ranging from single crystals to monodispersed nanoparticles in the 1-10 nm range. Molecular studies reveal that bond activation (C-H, H-H, C-C, CO) occurs at 300 K or below as the active metal sites simultaneously restructure. The strongly adsorbed molecules must be mobile to free up these sites for continued turnover of re...

pure and zno-doped ni0.1co0.9fe2o4 catalyst were prepared by co-precipitation method and thermal decomposition in air calcinated at 400-700°c and that treated with different amounts of zinc nitrate (0.46-2.25 w% zno). x-ray powder diffractometry, scanning electron microscopy (sem) and bet analysis of nitrogen adsorption isotherms investigated the crystalline bulk structure and the surface area ...

in this work, we investigated synthesis, magnetic properties of silica coated metal ferrite, (cofe2o4)/sio2 and manganese doped cobalt ferrite nanoparticles (mnxco1-xfe2o4 with x= 0.02, 0.04 and 0.06)/sio2 for possible biomedical application. all the ferrites nanoparticles were prepared by co-precipitation method using fecl3.6h2o, cocl2.6h2o and mncl2.2h2o as precursors, and were silica coated ...