the aim of this study is to evaluate the influence of ph on the synthesis of nanocrystallines cobalt ferrite by combination of sol- gel auto combustion and ultrasonic irradiation methods. two different fuels, urea and thiourea, along with metal nitrates (oxidant) were used to prepare cofe2o4 powders. the morphology of the resulting powders was investigated. the powders were characterized by x-r...

We systematically investigated the macroscopic quantum tunneling (MQT) phenomena of magnetization in CoFe,O, particles with a diameter ranging from 30 to 92 A in zero extemal magnetic field to remove the substantial influence of energy dissipation. For all of our samples, we observed the MQT phenomena in zero external magnetic field, in spite of the anticipation that a large magnetic field H co...

Nanostructured CoFe2O4 particles were prepared by a sonochemical approach, first by preparation of the amorphous precursor powders, followed by heat treatment at relatively very low temperatures. The precursor was prepared by sonochemical decomposition of solutions of volatile organic precursors, Fe(CO)5 and Co(NO)(CO)3, in Decalin at 273 K, under an oxygen pressure of 100-150 kPa. The amorphou...