Supagorn RugmaiChitnarong SirisathitkulKomkrich ChokprasombatPrawet RangsangaPhimphaka HardingToemsak SrikhirinPongsakorn JantaratanaSuranaree University of TechnologyWalailak UniversityMahidol UniversityKasetsart University2018-06-112018-06-112012-07-01Materiali in Tehnologije. Vol.46, No.4 (2012), 369-37315803414158029492-s2.0-84865503573https://repository.li.mahidol.ac.th/handle/20.500.14594/14376Two types of superparamagnetic nanoparticles, namely magnetite (Fe 3 0 4 ) and iron-platinum (FePt), with their surface modified by oleic acid and oleyleamine were synthesized using the the polyol process and dispersed in n-hexane. Vibrating-sample magnetometry (VSM) was used to characterize the FePt and the magnetic susceptibility of the Fe 3 O 4 was measured as a function of magnetic field and frequency at room temperature. Synchrotron, small-angle, X-ray scattering (SAXS) patterns revealed the polydispersity of the magnetic nanoparticles with average radii below 5 nm. As confirmed by transmission electron microscopy (TEM) images and dynamic light scattering (DLS), the Fe 3 0 4 nanoparticles had a larger average size. The DLS measurement gave larger radii than those obtained from the SAXS because of the effect of aggregates and surfactants.Mahidol UniversityMaterials ScienceArticleSCOPUS