Magnetism and Structure of Nanoparticles and Mesoscopic Systems

Synthesis and Magnetic Properties of Ni and Carbon Coated Ni by Levitational Gas Condensation (LGC)

“…The initial magnetization curve is not explained by the size effect. At previous studies, the virgin magnetization curve slightly spills over the limited hysteresis loop at 655 Oe [13]. We assume that this effect enhances when the size of the particles is reduced, at previous study.…”

“…The TEM image shows that nanocrystalline Ni powders consist of particles with the size ranges from 15 nm to 40 nm. The magnetic properties of nanopowders were affected by the size effect resulting from the anisotropy field and magnetic domain effect on the particles [13]. The morphologies of the carboncoated Ni nanocrystallites were characterized by TEM as shown in Figure 3(b).…”

“…The results indicated that all of the asmade materials were composed of only nanocapsules with a uniform particle size at and below 10 nm. At the previous study, nanocapsules consisted of outer multishells of carbon were observed using a high resolution TEM [13].…”

“…We assume that this effect enhances when the size of the particles is reduced, at previous study. With a decreasing particle size, the defects and the different magnetic structure on the surface of the particles are increased [13]. The nature of this irreversibility in high magnetic fields allows for the description of a physical model [12,13].…”

Thermal characterization of individual and mixed basic copper carbonate and ammonium metavanadate systems

“…6b of 1Cu:1V system calcined at different temperatures the above observation is clearly shown thus at 300 • C sample both overlapping signals of V 4+ and Cu 2+ are observed, moreover at 500 • C only V 4+ signal can be seen. This indicate that Cu Species exist either as separate CuO which is antiferromagnetic [19,20] and will not be detected by ESR or as Cu + species which also not detected by ESR. In addition, at 750 • C sample Cu 2+ species are overlapped clearly with lower amount of V 4+ species.…”